^Allies 0370ab

NIST SP 838-10

Project Summaries 1996

U.S. Department

of Commerce

Technology

Administration

National Institute

of Standards and

Technology

Project

Summaries 1996

NIST SP 838-10

NIST

Building &

File

Laboratory

Noel J. Raufaste

September 1 996

U.S. Department

of Commerce

Michael Kantor, Secretary

Technology

Administration

Mary L. Good,

Under Secretary for Technology

National institute

of Standards and

Technology

Arati Prabhakar, Director
National Institute of Standards U.S. Government Printing Office

and Technology Washington: 1996

Special Publication 838-1

Natl. Inst. Stand. Techno!.

Spec. Publ. 838-10

202 pages (Sept. 1996)

CODEN: NSPUE2

For sale by the Superintendent

of Documents

U.S. Government Printing Office

Washington, DC 20402
FOREWORD

The National Institute of Standards and

Technology's (NIST), Building and Fire

Research Laboratory (BFRL) is one of

NISPs seven Laboratories. The mission of

BFRL is to enhance the competitiveness of

U.S. industry and public safety through

performance prediction and measurement

technologies and technical advances that

improve the life cycle quality of constructed

facilities. Constructed facilities include aU

buildings and their furnishings and the

public and private utilities and public

works that support business, commerce,

industry, and homes. BFRL's efforts are

closely coordinated with complementary

activities of industry, professional and trade

organizations, academe, and other agencies

of goverrmient.

Construction is one of the Nation's largest

industries. In 1995, total construction

amounted to about $755 billion which is

12 percent of U.S. GDP (new construction

put in place amounted to about $527

billion and renovation contributed about

$228 billion). U.S. construction accounts

for more than six million jobs. More than

60% of the nation's wealth is invested in

constructed facilities.

BFRL's research is focused and linked with

collaborative private-and public-sector

activities to help achieve the National

Construction Goals (NCGs) developed

with industry by President Clinton's

National Science and Technology Council's

Subcommittee on Construction and

Building (C&JB). This Subcommittee

coordinates the federal construction-related

R&JD to enhance the competitiveness of

U.S. industry, public and worker safety,

and enviroimiental quality. BFRL is a co- chair of this 16 Federal agency body.

During the past 2 years, C&B has had

major interactions with construction

industry leaders; together they have defined

the NCGs. The goals are to provide costeffective technologies and practices by

2003 that will achieve the following

improvements in the life cycle performance

of constructed facilities over average 1994

practices:

o 50 percent reduction in delivery time,

o 50 percent reduction in operation,

maintenance, and energy costs,

o 30 percent increase in productivity and

comfort.

o 50 percent fewer occupancy-related

illnesses and injuries,

o 50 percent less waste and pollution,

o 50 percent more durability and

flexibility.

o 50 percent fewer construction illnesses

and injuries.

This annual report. Project Summaries 1 996,

presents BFRL's research during 1996.

These summaries show how our products

(performance prediction, measurement,

and test methods) support the industries of

construction in achieving the NCGs. BFRL

has focused its research in three principal

thrusts:

1 . High Performance Construction

Materials and Systems,

2. Automation in Construction and

Constructed Facilities,

3. Loss Reduction.

BFRL's research is in the areas of:

structural engineering, materials

engineering, mecharucal and environmental

systems, fire safety and engineering, fire

science, and applied economics.

In High Performance Construction

Materials and Systems, BFRL's projects

include: high performance concrete,

building life cycle cost computer program,

high performance mechanical systems,

finishes, and funushings, "natural"

alternative refrigerants for heat pumps, and

iii
our search, with industry, for alternative

fire suppressants.

Within the automation thrust, research is addressing development of new techniques

and standards for real-time construction

metrology and a national standard for

kinematic modeling of construction site

machinery and displaying graphical

representations. With U.S. industry, BFRL

is developing the capability to represent

and exchange information supporting the

design and construction of structural

systems using internationally accepted

protocols. Conformance tests are being

developed for products complying with

standards for the open exchange of

information between equipment from

different control vendors and between

different levels of control in hierarchal and

distributed building management systems.

In the loss reduction thrust, BFRL research

includes next generation design standards

for wind loads to develop key elements of

an improved wind load design standard

that will use existing databases and state-ofthe-art computational methods for

establishing site-specific design wind speeds

and the corresponding steady and

fluctuating structural loads. BFRL is constructing a user-friendly version of its

CFAST model (FASTLite) which can be

used by fibre protection engineers and fire

service personnel with a minimum of

training, and developing protocols to

quantify the accuracy of computer-based

predictive fire models.

Each of the BFRL research summaries is formatted by project title, the BFRL point

of contact, sponsor, description of the

research, and recent results.

BFRL's laboratory facilities are an

important resource. Facilities include:

six-degree-of-freedom structural testing

facility; large-scale structtiral testing facility

with the 53 MN (12-million poxmd)

universal structural testing machine;

environmental chambers; guarded hotplate; calibrated hot-box; plumbing tower;

building materials imaging and modeling

laboratory; large bum facility for

conducting experimental fires in full-scale

and related combustion toxicity facility;

large industrial fire test facilities; fire

suppression test facilities; and a fire

simulation laboratory.

BFRL works closely with its international

peer organizations to maintain awareness

of foreign research developments, assure that generic research efforts are complementary, and represent U.S.

interests in the preparation of international

standards and practices. BFRL cooperates

closely with other U.S. and foreign

laboratories in the conduct of its research.

More than 90 research associates from U.S.

industry, guest researchers from foreign

laboratories, and faculty members from

universities worked at BFRL during 1995

for periods averaging about a year. BFRL

has direct linkages with industry through

its 45 Cooperative Research and

Development Agreements (CRADAs).

BFRL participates in more than 130

national and international standardization

activities; provides leadership in these

national and international standardization

organizations and chairs more than 20

voluntary standardization activities.

Aimually BFRL publishes over 220 reports,

articles for research journals and articles for

professional and trade journals, and

computer model software packages. BFRL

staff aimually makes hundreds of

presentations at professional and techiucal

meetings of building community

organizations, is host to more than 1,700

visitors to its facilities, and responds to

more than 19,000 requests for information.

iv
BFRL conducts symposia in cooperation

with other organizations concerned with

building research and practice and hosts

biweekly Fire Research Seminars for NIST

staff and colleagues from the fire

commuiuty. These meetings are effective

means of transferring the latest knowledge

to practitioners and peer researchers. The

Fire Research Information Service (FRIS)

consisting of national and international fire

research literature and FIREDOC, the

automated database of fire research

literature, is the only comprehensive

national library resource for the fire

community.

At the beginning of FY 1996, BFRL had

about 217 employees of which 129 are professional staff, 71 have Ph.D.s, and 26

are registered engineers. BFRL's budget for

FY 1996 is $30 million. Funding comes

from direct appropriations ($18 million),

from other Federal agencies ($10 million)

and from the private sector ($2 million).

For further information about BFRL, its

facilities, opportunities for Guest

Researcher assignments, collaborative

programs, and contracted research, may be

reached through BFRL's Home Page at: httpy/www.bfrl.nist.gov or contact BFRL's

Office of Cooperative Research Programs,

Building 226, Room B250, NIST,

Gaithersburg, MD 20899. Persons

requesting information may want to

contact BFRL using facsimile number 301-

975-4032 or E-mail noel.raufaste@nist.gov.

r
i
CONTENTS

FOREWORD 111

EARTHQUAKE ENGINEERING

Seismic Evaluation of Buried Pipelines .... 3

Guidelines for Liquid Fuel Distribution

Systems 5

Performance Requirements for Passive Energy

Dissipation Systems for Buildings and

Lifeline Structures 6

Seismic Performance of Precast Concrete

Connections 7

Digital Database of Cyclic Lateral Load Tests

on Rectangular R/C Colunms 8

Seismic Strengthening Methodologies for

Existing Lightly RC Frame Buildings 9

Seismic Resistance of Partially Grouted

Masonry Shear Walls 10

Performance of Rehabilitated Masonry

Buildings and Development of Performancebased Rehabilitation Guidelines 12

Seismic Performance of Cladding

Systems 13

Seismic Performance of Non-Structural

Ceiling Components 14

Laterial Loads on Manufactured Homes . . 15

Management of the Interagency Committee

on Seismic Safety in Construction

(ICSSC) 16

Technical Assistance to FEMA Project Officer

(Existing Buildings) 18

Technical Assistance to FEMA Project Officer

(New Buildings) 18

Secretariat U.S. -Side Panel on Wind and

Seismic Effects 19

STRUCTURAL ENGINEERING

Construction Automation 23

High-Performance Concrete: Design and

Construction Practices 25

Fiber Reinforced Polymer Composite

Structures in Construction 27

High-Performance Steel 28

Fire Resistance of High-Strength

Concrete 29

Next Generation Design Standard for Wind

Loads 30

Assessment of Tubular Steel Joints in Existing

Offshore Structures 31

COATINGS AND OTHER

MATERIALS

Coatings Service Life Prediction

Consortium 35

Integrated Knowledge System for CorrosionProtective Coatings for High-Performance

Steel 36

Database Architectures for the Properties of

Construction Materials 37

Performance Criteria for Enclosures for LeadBased Paint 38

Vll
Performance Criteria for Selection of LiquidCoating Encapsulant for Lead-Based

Paint 39

Method for Evaluation of Performance of

Lead-in-Paint Measuring Devices Under

Simulated Field Conditions 40

Factors Affecting the Leaching of Lead from

Lead-Based Paint Films 42

Managing Lead-Related Hazards in

Housing 43

Technical Assistance on Lead-Based Paint

Issues 43

Performance of Tape-Bonded Seams in

Elastomeric Roofing Membranes 44

International Standards for Design Life of

Buildings 45

CONCRETE

Computer-Integrated Knowledge Systems for

High-Performance Construction

Materials and Systems 49

Computer-Integrated Knowledge Systems for

High-Performance Construction Materials

and Systems: High-Performance

Concrete 50

Microstructure-Property Relationships in

Random Porous Materials 52

Processing of High-Performance

Concrete 53

Three-Dimensional Microstructural/Kinetic

Model of Cement Hydration 54

Development of Microstructure and

Permeability in Mortar and Concrete .... 55

Characterization of Clinker, Cement, and

Raws in Cement Paste and Concrete .... 56

Transport Properties of High-Performance

Concrete 57

Matrix Microcracking in Polymer Composites

Under Environmental and Mechanical

Stresses 58

Service Life Prediction of Polymer/Fiber

Composites in Civil Engineering

Applications 59

Static and Fatigue Resistance of Polymermatrix Composites Irrunersed in Simulated

Sea Water 60

Spectral Ultra Violet-B Radiation

Database 62

Cementitious Materials Modeling Laboratory

(CMML) 63

Testing of U.S. Capitol Pavers 63

COMPUTER INTEGRATED

CONSTRUCTION

STEP for the Process Plant Industries ... 67

AMSANT for the Process Plant

Industries 68

Process Plant Engineering and Construction:

Structural Systems 69

STEP for the Building Industry 69

Object Oriented Implementation of

STEP 70

HEAT TRANSFER

Development of 2-Dimensional Heat and

Moisture Transfer 73

Test Procedures for Advanced Thermal

Insulation Products 74

Low-Temperature and High-Temperature

Thermal Insulation Reference Materials . . 75

Fibrous-Glass Thermal Insulation SRM . . 76

!

viii
A Photovoltaic Solar Water Heating

System 77

INDOOR AIR QUALITY

Indoor Air Quality Modeling with

Computational Fluid Dynamics 81

Chemistry and Mass Transport Modeling for

Indoor Air Quality 82

Development of lAQ Model for

Designers 83

Infiltration and Ventilation in Large

Buildings 84

Demonstration of Residential Ventilation

Systems 85

Indoor Air Quality Monitoring in Green

Buildings 86

lAQ Analysis of Residential Ventilation

Systems 87

Carbon Monoxide Detector Location in

Residential Buildings 88

MECHANICAL SYSTEMS AND

CONTROLS

Communication Protocols for Building

Controls 93

Real Time Fault Detection and

Diagnostics 94

Test Procedures for Furnaces, Boilers, and

Integrated Appliances 95

Commercial Furnace/Boilers, Central Air

Conditioners, Heat Pumps, and Water

Heaters 97

Test Procedures for Heat Pumps and Air

Conditioners 98

Test Procedures for Lighting Fixtures and

Systems 99

Plumbing Test Procedures 100

Development of Revised Test Procedures for

Water Heaters 101

Development of Revised Test Procedures for

Ranges and Ovens 102

Development of Revised Test Procedures for

Compact Refrigerators 103

Development of Revised Test Procedures for

Clothes Washers 104

Development of Revised Test Procedures for

Clothes Dryers 105

Development of Revised Test Procedures for

Dishwashers 105

Development of Revised Test Procedures for

Pool and Spa Heaters 106

THERMAL MACHINERY

Thermodynanrvic Performance of Alternative

Refrigerants and Refrigerant Mixtures . . 109

Thermodynamic Performance of Natural

Fluids as Alternative Refrigerants 110

Calorimetric and Visual Study of Heat

Transfer Enhancements with Alternative

Refrigerants Ill

FIRE MODELING AND

APPLICATIONS

Fire Performance Design of HighPerformance Materials Used in

Construction 115

BFS Lite 116

Fire Model Evaluation 117

Hazard Version 2 118

Hybrid Model Development 119

ix
Implementation of the FDMS Protocol . 120

Study of Heat and Smoke Movement and

Their Influence on Detector and Sprinkler

Response in Enclosed Spaces with Complex

Ceiling Geometries 121

Balanced Design 122

Enhanced Fire Safety Evaluation

System 123

Performance Standards 123

Fire Safe Elevators 124

Fire Spread in Painted Stairways 125

Experimental Application of Fire Hazard

Analysis for U.S. Passenger Train

Systems 126

Fire Research Information Services

(FRIS) 127

Fire Forum 127

Computing and Network Resources .... 128

RECENT GRANTS - FIRE

MODELING AND

APPLICATIONS

Interactive Virtual Environments for Fire

Simulation 129

Enhanced PC-based Building Fire Assessment

System 130

Accelerating the Application of Advanced Fire

Safety Design Methods in the U.S 131

Evaluation of Alternative Methods for Fire

Rating Structural Elements 132

Computational Heat Conduction for Zone

Fire Modeling 134

Flow Through Vents in a Compartment

Fire 135

Flows in Vertical Shafts 137

LARGE FIRE RESEARCH

Fire Hows 141

Large Eddy Simulation (LES)

Verification 142

Smoke Plume Trajectory From in situ Burning

of Crude Oil in Alaska - Phase II 143

In-situ Burning of Oil Spills 143

Demonstration of Water-Based Fire Fighting

Agents 144

Demonstration of New Residential

Suppression System Technologies 145

Evaluation of Water Mist System Technology

for Light Hazard Occupancy

Applications 146

Office Building Fire Research Program . . 147

Northridge Post-earthquake Fire

Assessment 148

Modification of Fire Protection Requirements

forNRC 149

Firefighter Thermal Exposure and the

Performance of Protective Clothing in

Thermal Environments 150

Development of a Sizing Standard for

Firefighter Protective Clothing 151

Large Fire Research Facility 152

RECENT GRANTS - LARGE FIRE

RESEARCH

Computational Modeling of Large Fire

Plumes 153

A Study of Two Phase High Liquid Loading

Jet Fires 154

X
Measurement of Flame Temperature Using

IR Technique and Air-Entrainment Velocity

Using PDPA 155

Fire Protection in Large Industrial Fires . 155

A Survey of Occupant Load Factors and Fuel

Load in Contemporary Office Buildings . 157

FIRE SENSING AND

EXTINGUISHMENT

Advanced Fire Detection 161

Fire Suppression Chemistry 162

Low Environmental Impact Fire

Extinguishment 1 64

Study of Technology for Detecting PreIgnition Conditions of Cooking-Related Fires

Associated with Electric and Gas Ranges and

Cooktops, Phase II 165

Fire Detection Strategies for High Bays . 1 66

Analysis of High Bay Hangar Facilities for

Detector Sensitivity and Placement .... 167

Radiative Ignition and Subsequent Flame

Spread Over Cellulosic Materials 176

Combustion of a Polymer (PMMA) Sphere in

Microgravity 177

Chemical Inhibitor Effects on Diffusion

Flames in Microgravity 178

Combustion of Silicone 179

Lean Flammability Limit as a Fundamental

Refrigerant Property, Phase II 180

Calibration Facility for Particle Size and

Concentration 181

Burning Rate of Real Materials 182

High Heat Flux Measurement

Standards 183

Evaluation of Fire Barrier Performance . . 184

Furniture Flammability 184

Test Method Development for Cigarette

Ignition Propensity 185

Polymeric Film Applied to Glass 186

RECENT GRANTS - FIRE

SENSING AND

EXTINGUISHMENT

Detection of Fires Through Reflected

Radiation 168

A Theoretical and Experimental Investigation

on Physical, Thermal and Chemical Effects of

Condensed Phase Fire Suppressants .... 169

Investigation of Droplet Penetration Through

Complex Openings of Compartments ... 171

MATERIALS FIRE RESEARCH

Flammability of Structural Composites . 175

RECENT GRANTS - MATERIALS

FIRE RESEARCH

Flame Resistance of Benzocyclobutene (BCB)

Functionalized Copolymers 187

Synthesis, Characterization and Systematic

Fire Safety Evaluation of High Volume and

Specialty Hydrolytically Stable Phosphate

Oxide Containing Polymeric Materials .. 188

Modeling of Combustion, Fluid Mechanics,

and Radiation in Buoyant Turbulent

Fires 189

Fire Growth Models for Materials 191

xi
SMOICE DYNAMICS RESEARCH

Carbon Monoxide Production and

Prediction 195

Decision Support Software for Hospitals

Financed by HUD-Guaranteed Loans ... 214

Economic Support for BFRL 215

Species Production for Turbulent Flame

Modeling 196

Vortex-Chemistry Interactions in

Methane/Air Diffusion Flames 197

RECENT GRANTS - SMOICE

DYNAMICS RESEARCH

Mixing and Radiation Properties of Buoyant

Luminous Flame Environments 198

Dynamics, Transport and Chemical Kinetics

of Compartment Fire Exhaust Gases .... 200

OFFICE OF APPLIED

ECONOMICS

Economic Support for the NIST Advanced

Technology Program 205

Measurement of BFRL Research

Impacts 206

Economics of New-Technology

Materials 207

Optimal Pricing of Standard Reference

Materials 208

Baseline Measures for National Construction

Goals 209

Building for Environmental and Economic

Sustainability (BEES) 210

Life-Cycle Costing Methodology 211

Provide Economic Support to NIST

Manufacturing Extension Partnership .. 212

Economic Support for the Office of Law

Enforcement Standards 213

xii
STRUCTURES DIVISION

EARTHQUAICE

ENGINEERING
I
Seismic Evaluation of Buried

Pipelines

Principal Investigators

Ronald D. Andrus

Structures Divisior\

301-975-6051

Bijan Mohraz

Structures Divisior\

301-975-6079

Riley M. Chung

Structures Division

301-975-6062

Sponsor

National Institute of Standards and Technology

Objective

To develop procedures for predicting damage to

buried pipelines caused by liquefaction, and for

seisrruc analysis, design, and construction of

these pipes.

Problem

Pipelines are vulnerable to large earthquakeinduced ground displacements such as those

associated with liquefaction, landslide, slope

failure, and fault displacement. Basic types of

ground displacement associated with

liquefaction include flow failure, lateral spread,

transient oscillation, and settlement. To

rationally design pipelines, mapping critical areas is necessary. Screening techniques based

on geology, hydrology, and soil conditions can

identify areas along lifeline corridors requiring

more rigorous analyses. These areas can extend

for several kilometers, however. Method for

rapid evaluation of large areas where such

problems may occur is a critical issue.

Further, current computational model used in

the design of buried pipes considering soil-pipe

interaction lack reliable input data on several

critical parameters such as frictional resistance

and strains developed at the soil-pipe interface.

These parameters and others were developed

decades ago by subjecting buried pipes under

static load conditions. The validity of these

parameters under seismic conditions is very

questionable. In addition, there is insufficient

information available on materials and response

characteristics of older buried pipes. The lack

of information, therefore, has become a major

concern on how reliably their performance can

be predicted or assessed by any analytical

method. While many analytical models can

simulate pipe performance under seismic

loading, none can predict the effect on buried

pipes at fault crossings or areas of ground

deformation caused by liquefaction.

Approach

During FY 1996, BFRL will perform two tasks:

1. Develop methods to predict liquefaction and

ground deformation potential of soil

deposits. This work will be done in three

components and in cooperation with

industry and academia:

- Apply the system identification technique

to the Lotung data made available by

EPRI. Research will build on the work

started in 1994 to estimate material

damping of Lotung soils for the full scale

of earthquake-induced strains using the

system identification (SI) method. The

recording of site response for a full suite

of earthquakes at Lotung makes such an

analysis possible. Estimates of material

damping by the SI method will be

compared with published estimates made

using laboratory and other analytical

techniques. The work will be jointly

conducted by BFRL and the Colorado

School of Mines.

- Verify the applicability and efficiency of

the Spectral -Analysis-of-Surface-Waves

(SASW) technique for lifeline

applications. This effort builds on the

Spring 1996 field demonstration work of

the SASW technique for rapid

determination of layer thickness and

small-strain shear wave velocity. Four

sites in the San Francisco Bay area were

selected for testing. Testing and initial

data reduction jointly will be performed

by BFRL and the University of Texas at

Austin.

Perform a feasibility study of the strainenergy approach to liquefaction

assessment using shear wave velocity.

The strain-energy approach provides a

3
more rational framework for deciding the

liquefaction potential. Strain energies

required to reach various pore water

pressures in the laboratory and in the

field (the Wildlife liquefaction site) will

be compared. Bechtel Corporation, San

Francisco is doing this effort, in

collaboration with BFRL and the

Colorado School of Mines.

2. Examine issues related to soil-pipe

interaction under earthquake loading. This

work involves four components:

Conduct a literature survey on

performance of pipelines in past

earthquakes to decide different modes of

failure, and the methods currently used in

their design.

Develop simplified analytical procedures

for determining forces and deformation

in buried pipes. The analysis will account

for soil-pipe interaction, resulting from

the various degree of soil deformation

around the pipe.

Design a comprehensive test program to

provide information on the critical

parameters which are currently lacking,

but needed as input for analytical models.

Conduct limited tests on segments of

pipes buried in a container of soil

subjected to typical earthquake ground

motions on a shake table. The tests include static and dynamic conditions.

Part of the experimental component of

the task is expected to be carried out in

collaboration with the U.S. Army

Construction Engineering Research

Laboratory.

It is expected that Tasks 2 will take

approximately 3 years to complete.

Recent Results

Andrus, R.D., and Stokoe, KH., II, "Guidelines

for Evaluation of Liquefaction Resistance Using

Shear Wave Velocity," Proceedings, NCEER

Workshop on Evaluation of Liquefaction Resistance,

January 1996.

Glaser, S. D. and Chung. R. M., "Use of

Ground Improvement for Liquefaction

Mitigation Potential for Lifelines," Proceedings,

U.S. -Taiwan Geotechnical Collaboration Workshop,

Taipei, Taiwan, 1995.

Andrus, R. D. and Chung, R. M., "Costeffective Ground Improvement Techniques for

Liquefaction Remediation Near Lifelines,"

Proceedings, 27th Joint Meeting of the U.S. -Japan

Cooperative Program in Natural Resources Panel on Wind and Seismic Effects, Technical

Memorandum No. 3387, Public Works

Research Institute, Japan 1995.

Andrus, R.D., "Surface Wave Method - A Tool

for Lifeline Earthquake Engineering,"

Proceedings, Earthquake Engineering Site

Characterization Workshop, U.S. Army Corps of

Engineers, Vicksburg, Mississippi 1995.

Andrus, R D. and Chung, R. M., Ground

Improvement Techniques for Liquefaction Remediation

near Existing Lifelines, NISTIR5714, National

Institute of Standards and Technology, October

1995.

Glaser, S. D., and Chung, R.M., "Estimation of

Liquefaction Potential by In Situ Methods,"

Earthquake Spectra, EERI, Vol.1 1, No.3, 1995.

Glaser, S. D., "Surface Displacements due to

Earthquake Excitation for Saturated Sands,"

Earthquake Spectra, EERI, Vol. 10, No. 3, 1994.

Glaser, S. D., "Application of Parametric

Models for Estimation of Soil Parameters,"

Proceedings, 8th International Conference of the

Association for Computing Methods and Advances in

Geomechanics,Yo\. 1, 1994.

Glaser, S.D., and Chung, R.M., "Evaluation of

Liquefying Soil Through Time Using System

Identification," Proce^t/m^i, 5di U.S. -Japan

Workshop on Earthquake Resistant Design ofLifeline

Facilities and Countermeasures Against Soil

Liquefaction, Technical Report NCEER-94-0026,

NCEER. 1994.

4
Guidelines for Liquid Fuel

Distribution Systems

Principal Investigators

Bijan Mohraz

Structures Division

301-975-6079

Riley M. Chung

Structures Division

301-975-6062

Sponsor

National Institute of Standards and Technology

Objective

To develop guidelines for the seismic design and

construction of liquid fuel distribution

systems •

Problem

While there was no severe damage to liquid fuel

systems; storage tanks, connections, buried and

elevated piping, during recent earthquakes such

as the 1994 Northridge, California and the

1995 Kobe, Japan earthquakes, the potentials

for devastating effects can occur, such as damage to LNG tanks and to major trunk lines.

For instance, a major Midwest earthquake may

cause severe damage to liquid fuel distribution

lines that provide heating fuels for residents in

the New England area. When this happens in

the winter, it results in major spills in the

vicinity where the pipes break and creates

hardship, perhaps life losses in the New

England region from loss of heating fuel. Most

of the existing systems, especially those found

east of the Rocky's, were designed with no or minimum seismic consideration. It is important

that this problem be addressed to determine

their vulnerability and provide guidance how

existing systems should be strengthened and

new systems designed.

Approach

During FY 1996, BFRL will perform two tasks:

1. Assess seismic risks of liquid fuel systems.

This work is to review and integrate available

methods and procedures of seismic risk

assessment and loss estimation, develop a framework for risk assessment that can

logically accommodate the state of the art results of BFRL work addressing the physical

and functional performance of the liquid fuel

systems subject to earthquakes, identify and

highlight the design issues that must reflect

the risk concept during the development of

design guides, and develop and draft an

outline of design guides. BFRL is conducting this work through the University

of Southern California.

2. Evaluate the seismic performance of liquid

fuel tanks. This effort involves the

documentation and evaluation of the

performance of liquid fuel tanks during the

past and recent major earthquakes, assess

their performance with respect to the current

design and construction practices, and

develop recommendations for improving

their future performance.

This project is partially to support a National

Lifeline Plan developed by NIST and FEMA,

with participation from the private sector, that

has been submitted to Congress by FEMA. The

Plan recommends the establishment of a

Lifeline Seismic Safety Executive Board to

coordinate and execute projects aimed at

developing design and construction guidelines

for lifeline systems including the liquid fuel

systems.

Recent Results

New project

5
Performance Requirements for

Passive Energy Dissipation Systems

for Buildings and Lifeline Structures

Principal Investigators

Andrew Taylor

Structures Division

301-975-6078

Riley M. Chung

Structures Division

301-975-6062

Sponsor

National Institute of Standards and Technology

Objective

To develop and verify guidelines for prequalifi cation, prototype and quality of seismic

isolation systems.

Problem

Seismic isolation has been proven to be effective

in reducing the level of response in structures

during strong earthquake ground shaking. In

practice, the components of the isolation system

undergo an extensive series of prototype and

quality control tests before installation.

Recently BFRL completed an extensive set of

guidelines for conducting these tests. These

guides were developed with the assistance of an

Oversight Committee of five experts from the

field of seismic isolation. They were refined to

reflect the comments received from about 40

reviewers, and the recommendations developed

at a BFRL workshop in July 1994. To develop

confidence in the guidelines, and to foster wider

adoption of the proposed testing procedures,

test must be conducted on typical isolation

components to evaluate the guidelines. These

tests are needed to expose inconsistencies,

omissions of important data, or other

unforeseen problems with the procedures.

Approach

During FY 1996, BFRL will perform three tasks:

1. Publish the Final BFRL Guidelines.

Incorporate into the draft guidelines the

final review comments and

recommendations from mail-in reviews,

BFRL workshop, and the Oversight

Committee. This document will serve as the

pre-standard document for development of

the ASCE national consensus standard.

2. Support Development of a National

Consensus Standard. As an ongoing

component of this project, BFRL will

provide the secretariat of the ASCE

standard's committee on testing of base

isolation systems. The committee was

formed in August of 1995, and the first

meeting was held in September. Subsequent

meetings will take place every 6 months, for

approximately 2 years.

3. Test Program for Assessing and Evaluating

Guidelines. A detailed plan has been

developed for the experimental program,

through consultations with researchers at the

University of Delaware, the University of

Maryland, and the Southern Methodist

University. The objectives of the

experimental program will be to evaluate the

NIST testing guidelines, and study three

other issues which affect test methods: the

ultimate capacity of seismic isolators; the

effects of bilateral loading on isolator

performance; and improved methods for

detecting flaws in elastomeric bearings.

During FY 1996, 23 isolators will be

evaluated in two phases. The first phase of

tests will involve primarily uniaxial

compression loading and is planned for early

FY 1996. The second phase will involve

testing isolators under simultaneous uniaxial

compression and cyclic lateral shear loading.

These tests will be conducted in the BFRL

Tri-Directional Testing Facility (TTF) and

possibly its 53 MN capacity universal testing

machine.

Recent Results

Shenton, H.W., and Taylor, A.W., "Guidelines

and Benchmarks for Analysis of Isolated

Buildings," Proceedings, ASCE Structures Congress,

Chicago, April 1996.

Shenton, H.W., Summary and Results of the NIST

Workshop on Proposed Guidelines for Testing and

Evaluation of Seismic Isolation Systems, July 25,

1994, San Francisco, Ca, NISTIR5785, National

Institute of Standards and Technology, January

1996.

6

I
Shenton, H.W., Guidelinesfor Pre-Qualijtcation,

Prototype, and Quality Control Testing of Seismic

Isolation Systems, NISTIR5800, National

Institute of Standards and Technology, January

1996.

Taylor, A.W., Shenton, H.W., and Chung,

R.M., "Standards for Testing and Evaluation of

Seismic Isolation Systems," Seismic, Shock, and

Vibration Isolation. ASME/JSME PVP

Conference, Honolulu, July 1995, PVP-Vol

319, pp. 39-43, 1995.

Shenton, H.W., Taylor, A.W., and Lew, H.S.,

"Test Requirements for Base Isolation,"

Proceedings, 27th Joint Meeting on Wind and

Seismic Effects, U.S. -Japan Panel on Wind and

Seismic Effects, UJNR, Technical Memorandum

No. 3387, Public Works Research Institute,

Japan, May 1995.

Seismic Performance of Precast

Concrete Connections

Principal Investigator

Geraldine S. Cheok

Structures Division

301-975-6074

Sponsor

National Institute of Standards and Technology

Objective

To revise the design guidelines for moment

resistant precast concrete beam-column

connections for adoption into building codes

and standards.

Problem

Proposed revisions to the building codes require

careful attention to the content and wording of

the proposed changes. Attention is required to

avoid conflicts with existing code requirements,

the unintentional exclusion of materials and/or

procedures, and potential mistakes caused by

misinterpretation of the proposed changes.

Approach

During FY 1996, BFRL will coordinate its research with private sector consulting engineers

and academic researchers. The proposed

changes will be presented to the SEAOC Ad

Hoc Committee on Precast Structures on

Seismic Zones. The Committee will provide

guidance to the technical content and

acceptability of the changes by the SEAOC

Seismology Committee. Interaction with the ad

hoc committee will include participation in the

scheduled meetings to provide technical

interpretation of the proposed design

guidelines. To verify a procedure proposed in

the recommended guidelines, BFRL researchers

will collaborate with a precast construction

company in processing data from additional

tests sponsored and conducted by the precast

company.

Tests of the horizontal connections for precast

panels will be completed and a report will be

published. Recommendations for vertical and

horizontal connections for precast panels will be

submitted to ACI Technology Transfer

7
Committee (TTC) for their consideration as a demonstration project. Subsequently, a proposal for design provisions will be made by

ACI TTC for inclusion in ACI 318 Building

Code.

Recent Results

Cheok. G.S.. Stone, W.C., and Nakaki, S.P.,

Simplified Design Proceduresfor Hybrid precast

Concrete Connections, NISTIR5765, National

Institute of Standards and Technology,

February 1996.

Stone, W.C., Cheok, G.S., and Stanton, J.F., "Performance of Hybrid Moment-Resisting

Precast Beam-Column Concrete Connections

Subjected to Cyclic Loading," AC/ Structural

Journal, Vol.92, No.2, American Concrete

Institute, Detroit, MI, pp. 229-249, MarchApril 1995.

Cheok, G.S., and Stone, W.C., Performance of

1/3-Scale Model Precast Concrete Beam-Column

Connections Subjected to Cyclic Inelastic Loads -

Report NoA, NISTIR5436, National Institute

of Standards and Technology, June 1994.

Cheok, G.S., Stanton, J.F., and Seagren, D.,

"Beam-to-Column Connections for Precast

Concrete Moment-Resisting Frames," Proceedings

of the Fourth Joint Technical Coordinating Committee

on Precast Seismic Structural Systems, May 1994.

Digital Database of Cyclic Lateral

Load Tests on Rectangular R/C

Columns

Principal Investigators

William C. Stone

Structures Division

301-975-6075

Andrew Taylor

Structures Division

301-975-6078

Sponsor

National Center for Earthquake Engineering

Research (NCEER)

Objective

To develop a comprehensive digital data base of

cyclic lateral load tests on rectangular reinforced

concrete columns.

Problem

To develop confidence in inelastic analysis

algorithms for reinforced concrete structures,

the algorithms must be calibrated against

laboratory data from tests on reinforced

concrete members. Without such a calibration,

the inelastic analysis algorithms are essentially

useless. Because of the high variability inherent

in tests of reinforced concrete members, and

because of the wide range of member geometries

and material properties covered by the

analytical models, large databases of

experimental results are required for adequate

calibrations. There is currently no

comprehensive, worldwide database of results

from cyclic lateral load experiments on

rectangular columns

Approach

During FY 1996, BFRL will develop a comprehensive digital database of cyclic lateral

load tests on rectangular reinforced concrete

columns. This work will build on the past

year's effort involving a literature review that

identified worldwide cyclic lateral load tests and

copies of test reports and publications on digital

data. For those tests which are reported only in

analog format, the load-deflection plots will be

digitized using a computer work station.

I

i
di^tizing tablet and special digitization

software written expressly for this purpose at

BFRL. Finally, the digital data will be arranged

in a uniform format, ausdliary information

about the tests wdll be tabulated, and the

database will be described in a report

accompanied by a computer disk.

Recent Results

Completed collecting laboratory records on tests of rectangular columns.

Seismic Strengthening

Methodologies for Existing Lightly

RC Frame Buildings

Principal Investigators

Geraldine S. Cheok.

Structures Division

301-975-6074

Long Phan

Structures Division

301-975-6077

Sponsor

National Institute of Standards and Technology

Objective

To develop guidelines for strengthening lightly

reinforced concrete (LRC) frames using infill walls.

Problem

A workshop conducted by NIST on the seismic

rehabilitation of LRC frames in FY 1995

identified research needs in this area. Several

issues were categorized as high priority. One

issue addressed the prediction of the behavior of

LRC frames, unstrengthened and strengthened.

Accurate prediction of frame behavior would

allow for rational decisions on whether to

rehabilitate or not and the most appropriate

rehabilitation method. How well the

connections perform their intended purpose of

load transfer influences the success of any

rehabilitation method. Currently, the design of

connections is based on shear friction theory

which is conservative for this application and

typically results in the requirement for a great

many connectors. There is an economic

incentive to rationally determine the required

amount of connectors.

Approach

During FY 1996, BFRL will develop analytical

methods to predict the behavior of LRC frames

strengthened with infill walls. Fundamental to

such methods is the ability to model the

behavior of the connectors accurately. The

development of a relationship to allow for the

accurate prediction of connector behavior would

therefore enhance the reliability of current

9
analytical methods. The development of this

relationship will require several years and will

involve:

1 . Determination of available data on the

load-deformation relationship up to failure

of typical connectors used for connecting

new elements to existing LRC frames.

2. Development of an empirical load

deformation relationship of the connectors

based on parameters including connector

diameters, concrete strength, embedment

depth, etc.

3. Determination of available finite element

analysis packages where the connector

relationship, developed in the previous step, can be implemented to enable the

determination of the inelastic behavior of

LRC frames up to failure. Modifications

may have to be made to the program to

fulfill the stated objective.

4. Parametric study using the finite element

program.

5. Experimental tests to verify the validity of

the analytical results.

Recent Results

Cheok, G. S., Editor, Proceedings, Workshop on the

Seismic Rehabilitation ofLightly Reinforced Concrete

Frames, NISTIR5741, National Institute of

Standards and Technology, November 1995.

Phan, L. T., Cheok, G. S., Todd, D. R and Lew,

H. S., Strengthening Methodologyfor Lightly

Reinforced Concrete Frames: Recommended Design

Guidelinesfor Strengtiiening with Infill Walls,

NISTIR5682, National Institute of Standards

and Technology, July 1995.

Phan, L. T., Todd, D. R., and Lew, H.S.,

Strengthening Methodologyfor Lightly Reinforce

Concrete Frames - II. Recommended Calculation

Techniquesfor die Design ofInfill Walls, NISTIR

542 1 , National Institute of Standards and

Technology, May 1994.

Seismic Resistance of Partially

Grouted Masonry Shear Walls

Principal Investigators

Gerry Cheok

Structures Division

301-975-6074

Arturo E. Schultz

Structures Division

310-975-5301

Sponsor

National Institute of Standards and Technology

Objective

To define the strength and deformation of

partially grouted masonry shear walls at the

cracking and ultimate limit states, and the

influence of critical parameters on wall

behavior.

Problem

The behaviors of masonry shear walls have been

the subject of increased attention during the

past fifteen years. However, effort has been

aimed at fully grouted, reinforced walls. Due to

the lack of physical data on the response of

partially grouted masonry walls to in-plane

lateral loads, no acceptable design formulas are

available for predicting shear strength of such

walls. The limited data available also suggests

that empirical formulas for shear strength of

fully grouted, reinforced walls have very limited

applicability for determination of the shear

strength of partially grouted, lightly reinforced

shear walls.

The tests and analyses conducted by BFRL in

FY 1995 for the reinforced bond beams, showed

that the load resisting mechanism in partially

grouted walls is considerably different from that

for fully-reinforced and fully grouted walls.

Cracking of the intersection between bond

beams and grouted vertical cells may be the

controlling mechanism for wall resistance, as it limits how much stress that horizontal

reinforcing bars can carry.

Approach

During FY 1996, BFRL will evaluate the second

10
series of specimens of highest priority, which

target the replacement of bond beams with

special (ductile) bed joint reinforcement. This

series of experiments will be conducted on

partially grouted masonry shear walls made

using hollow concrete units with six specimens.

The research will study the amount of

horizontal reinforcement and aspect ratios on

shear behavior of walls in which all horizontal

reinforcement is provided by welded grids

placed in the bed joints. Horizontal

reinforcement ratios equal to 0.0005 and

0.0012 are incorporated in the experimental

program, with aspect ratios of 0.5, 0.7 and 1.0. These specimens are nominally identical to

those in Series II (tested and analyzed in FY

1995) except the replacement of bond beams

with bed joint reinforcement.

Analytical activities will be conducted in parallel

with the experiments, and these include

development of semi-empirical simplified

expressions for predicting cracking and ultimate

shear strengths and deformations. Similar

efforts at NIST have led to the improvement of a shear strength formula for fully-grouted,

reinforced masonry shear walls. The behavior

of partially grouted masonry shear walls using a more systematic procedure that can give global

and local information regarding states of stress and strain at cracking and yielding will be

performed. For this purpose, two levels of finite

element analysis of partially grouted walls are used. A nonlinear finite element computer

package for masonry shear walls (FEM) will be

use to verify the applicability of nonlinear finite

element analyses for determining peak strength

and initial stiffness of partially-grouted masonry

walls.

Research results from this study will be

submitted to the Masonry Standards Joint

Committee (MSJC) and Building Seismic

Safety Committee (BSSC) for possible

incorporation in the ACI-ASCE-TMS

recommended building code provisions and the

NEHRP (National Earthquake Hazard

Reduction Program) suggested guidelines

provisions, respectively.

Recent Results

Schultz, A. E., "Minimum Horizontal

Reinforcement Requirements for Seisnruc

Design of Masonry Walls," TMS Journal, Tlie

Masonry Society, (for publication).

Schultz, A.E., "Seismic Resistance of Partially

Grouted Masonry Shear Walls," 11th World

Conference on EartJiquake Engineering, Acapulco,

Mexico, June 1996.

Schultz, A. E., NIST Research Program on the

Seismic Resistance ofPartially-Grouted Masonry

Shear Walls, NISTIR5481, National Institute

of Standards and Technology, June 1994.

11
Performance of Rehabilitated

Masonry Buildings and

Development of Performance-based

Rehabilitation Guidelines

Principal Investigator

Riley Chung

Structures Division

301-975-6062

Sponsor

Federal Emergency Management Agency

Mitigation Directorate

Objective

To document the performance of rehabilitated

unreinforced masonry buildings during the

Northridge earthquake, evaluate the

effectiveness of current rehabilitation practices,

and develop a compendium of rehabilitation

techniques with guidance for designers.

Problem

Reinforced masonry construction has been used

in California since 1934 after the Long Beach

earthquake. However, many unreinforced

masonry buildings (URMs) still exist in the Los

Angeles area. Many of these buildings have

been "rehabilitated" as the result of the

rehabilitation requirements known as "Division

88" mandated by the City of Los Angeles. The

requirements apply to all URMs other than one

and two-family dwellings and small apartment

buildings of less than five living units.

Despite rehabilitation, many URMs in Santa

Monica and in Hollywood were heavily

damaged as the result of the January 1994

earthquake. As a life-safety measure, current

rehabilitation practices appear to have been

successful in this earthquake-there were no

complete collapses and no deaths of occupants.

In contrast, a significant portion of the fatalities

due to building failures during the 1989 Loma

Prieta earthquake were the result of out-ofplane failures of URM walls that collapsed onto

adjacent buildings, sidewalks, streets, and

parking lots. Yet, the Northridge earthquake

occurred at 043 1 making it unlikely for deaths

or injuries to occur on the sidewalks adjoining

the damaged URMs. Furthermore,

rehabilitation was not successful in preventing

property damage, which can lead to significant

economic losses as the result of building repair

and the associated business disruption.

The Northridge earthquake offers an

opportunity to examine the effectiveness of the

current rehabilitation practices as exemplified

by the implementation of "Division 88." There

are many rehabilitated URMs that this

earthquake affected. There is a need to

systematically develop a database that is as complete as possible to document the locations

of these URMs and their performance. The

database will be developed from building

department records rather than from site visits

of individual buildings. The earthquake also

resulted in many strong motion records

throughout the region. Comparison of URM

location and performance to the characteristics

of local strong motion records, and to

traditional MMI Intensity maps, will allow a comprehensive evaluation of the effectiveness of

current rehabilitation requirements.

Approach

During FY 1996, BFRL will develop a compendium of rehabilitation techniques, for all

levels of performance. Information gaps will be

identified. This document will provide

immediately usable information for designers,

and will complement BFRL's work for FEMA in

development of rehabilitation guidelines for

multiple performance objectives for all building

types by 1997. The work is being performed in

collaboration with outside investigators.

Results

New project

12
Seismic Performance of Cladding

Systems

Principal Investigators

Andrew W. Taylor

Structures Division

301-975-6078

Sponsor

National Institute of Standards and Technology

Objective

To evaluate seismic performance of exterior

architectural cladding elements during the

Northridge earthquake and develop energy

dissipating cladding systems for seismic retrofit

and design of new buildings.

Problem

Although many cladding elements are not

specifically designed for seismic forces, they

participate in resisting lateral loads as they

deform with the framing system. It has been

reported that cladding systems sustained

damage during the Northridge earthquake,

particularly those on steel frame structures.

The seismic performance of buildings could be

improved by utilizing effectively the cladding

system to dissipate energy. Energy-dissipating

cladding can be applied to both new

construction and seismic retrofit.

Approach

During FY 1996, BFRL will document the

performance of architectural cladding systems

during the Northridge and other earthquakes.

Current design criteria and code requirements

will be critically evaluated based on observed

cladding performance. Next, the performance

of energy dissipating cladding connector

hardware will be studied. This will be primarily

an experimental investigation, using existing

test fixtures at Georgia Institute of Technology.

The goal of this work will be to determine how

different types of energy dissipating connectors

behave (e.g., elastomeric connectors, steel clip

angles, and other specially designed steel

connectors). The hysteretic properties of the

connectors will be established, and desirable

modes of connector performance will be

defined. Following this effort, the

contributions of cladding to the stiffness and

damping of the overall structural system will be

determined. Presently, it is not clear to what

degree cladding systems participate with the

main structural frame of a building during

earthquake shaking. This work follows

naturally on the connector performance studies

described above, since the energy dissipating

properties of connectors have a major influence

on the interaction between the cladding system

and the structural frame. The third project task

will be to compare the full-scale and scale-model

building performance data with analytical

models. Finally, based on the results of the

above work, seismic design guidelines for

building cladding systems will be developed.

Recent Results

Cladding Research Institute, Literature Review on Seismic Performance of Building Cladding Systems,

GCR-95-681, National Institute of Standards

and Technology, February 1995.

13
Seismic Performance of NonStructural Ceiling Components

Principal Investigators

Long T. Phan

Structures Divisior\

301-975-6077

Andrew Taylor

Structures Division

301-975-6078

Sponsor

National Institute of Standards and Technology

Objective

To develop methods for reducing seismic

damage to non-structural components of

buildings.

Problem

It has been observed in past earthquakes that

damage to non-structural components and

secondary systems can have a great effect on the

safety of occupants and loss of property, and

sometimes the effects of non-structural damage

can be even greater than the effects of structural

damage. The terms "non-structural

components" and "secondary systems" refer to a number of items. They include, for instance,

cladding, ceilings, building contents, equipment,

and HVAC, plumbing, and electrical systems.

Most of the past efforts in the NEHRP program

have focused on improvements of the structural

design of buildings to prevent total collapse. As

a result, most newly constructed buildings stand

a good chance that they will not collapse from

an anticipated earthquake. It is only recently

that attention has been paid to the performance

of non-structural components and secondary

systems.

A major problem observed in all recent major

U.S. earthquakes has been the seismic

performance of the components located in or above suspended ceilings in commercial office

buildings. These components include the

suspended acoustical tile ceilings themselves;

fire sprinkler systems; light fixtures; and HVAC

ducts. Problems arise because these

components are co-located in the ceiling area.

and their movements during an earthquake are often incompatible. For example, fire sprinkler

heads usually project through suspended

acoustical tile ceilings. During an earthquake,

the movements of the suspended ceiling and the

sprinkler pipes are incompatible, so that the

sprinkler heads are damaged. Not only does

this decrease the ability of the sprinkler system

to suppress post-earthquake fires, but it also

may result in broken sprinkler heads and

flooding of the building contents. Another

example is distortion of the acoustical tile ceiling grid, which may cause lighting fixtures

and ventilation grills resting in the grid to fall.

Thus, studies of the interactions of components

located in and above suspended ceilings are required to reduce non-structural damage in

buildings. Design guidelines need be developed

to ensure compatible deformations and

adequate seismic resistance of these

components.

Approach

During FY 1996, BFRL will perform a literature

review; analytical modeling; and shake table

testing. The study will be initiated with a review of the seismic performance of nonstructural building components, and the state- of-the-art of seismic design methods for nonstructural components. This will be followed by

a search for existing literature on seismic

behavior of non-structural components in

ceilings (pipes, HVAC ducts, suspended

ceilings).

Computer models will be evaluated which could

be used to perform dynamic analyses of ceiling

systems. These models would include

provisions for real-time opening and closing of

gaps between components; realistic component

flexibility; and possibly progressive damage of

components. Initial modeling would be in two

dimensions (one horizontal axis and the vertical

axis), and later modeling might be extended to

three dimensions.

Once a satisfactory modeling method has been

established, realistic ceiling component data will

be required. These include component masses,

stiffness and strengths, the layout of

components in the ceiling area, and appropriate

14
input seismic records. Some simple testing of

typical components, such as fire sprinkler pipes,

may be required to obtain stiffness data.

Several typical geometric layouts of ceilings

system will be defined, and three to five input

earthquake records of varying magnitudes.

Using the forces and differential displacements

will be recorded. Observed problem areas, such

as impact sites and locations of high stress will

be studied, and remedial measures will be

proposed. Alterations will be made to the

computer model to remedy the problem areas, and the computer analyses will be repeated to

assess the degree of improvements.

Based on the analytical studies,

recommendations will be made for improving

the seismic design of components within and

above suspended ceilings in buildings. The

recommendations include minimum or maximum clearances between components;

strengths for anchorages; and fixing some

components or for freeing other components.

The analytical phase of the project will be

followed by an experimental phase, expected to

commence in FY 1997. The purpose of the

experimental phase is to verify the analytical

model, and to evaluate the recommended design

procedures developed earlier in the project. In

the experimental phase, a full scale model of a

typical ceiling and plenum area will be

constructed on a shaking table. The model will

include the suspended ceiling system, pipes (fire

suppression, water, sewer, gas), and HVAC

ducts. This model will be subject to a variety of

earthquake motions, and damage to the model

components will be observed. The model will

then be altered according to the design

procedures developed earlier, to determine the

extent to which these practices improve the

dynamic behavior of the model. The design

guidelines will be modified as necessary to

reflect the findings of the experimental

program.

Recent Results

Phan, L.T. and Taylor, A.W., State of the Art

Report on Seismic Design Requirements for Nonstructural Building Components, NISTIR 5857,

National Institute of Standards and

Technology, June 1996.

Lateral Loads on Manufactured

Homes

Principal Investigator

R. D. Marshall

Structures Division

301-975-6071

Sponsor

National Institute of Standards and Technology

Objective

To develop performance-based requirements

and recommended procedures for the design of

manufactured home anchoring and support

systems to resist lateral forces.

Problem

The Northridge Earthquake of January 1 7,

1994 again showed the vulnerability of

manufactured homes to strong ground motions.

Most of the damage to manufactured homes

involved the shifting or lateral movement of

homes about their supporting piers so that the

piers either jackknifed or punched through the

floor system. In several instances the lateral

movement was sufficient to rupture gas lines, or

gas lines were ruptured as the homes fell from

their supporting piers. In one manufactured

home park, at least six individual ignitions of

leaking natural gas occurred, and the resulting

fires consumed several nearby units. Many

affected homes were equipped with secondary

support systems whose function is to catch the

manufactured home and thus reduce damage

when primary support is lost. However, these

secondary systems frequently lacked sufficient

lateral bracing to resist earthquake forces.

Although it is well established that wind loading

will dictate the strength requirement for

manufactured home anchoring systems in most

situations; earthquake loading subjects the

various elements of these systems to many

cycles of reversed loading in the horizontal and

vertical directions. Frictional forces and the

lateral resistance of supporting piers mobilized

under wind loading cannot be relied upon in an

earthquake. To predict anchorage and support

system performance under earthquake loading,

the stiffness, ductility, energy dissipation and

15
softening characteristics of these systems must

also be known. To date, little attention has

been given to this problem so that the required

databases from which to formulate adequate

design criteria is nonexistent.

Approach

During FY 1996. BFRL will:

1 . Develop a computer-based model to perform

sensitivity studies of traditional anchorsupport systems. The model will

accommodate various distributions of

superstructure dead load and stiffness,

anchorage and pier stiffness, and ductility of

chassis-to-pier connections. Ground motion

input wall range from constant-amplitude

cyclic displacements to actual strong-motion

time histories.

2. Develop envelopes of reaction forces (piers,

pier-to-frame connections, frame-to-anchor

ties, and soil anchors) as a function of

ground acceleration, damping, and system

mass and stiffness.

3. Develop typical load time-histories for the

components identified under Item 2 above.

Recent Results

New project

Management of the Interagency

Committee on Seismic Safety in

Construction (ICSSC)

Principal Investigator

Ann Bieniawski

Structures Division

301-975-6065

Sponsor

Federal Emergency Management Agency

Mitigation Directorate

Objective

To facilitate and expedite the work of the Inter- agency Committee on Seismic Safety in

Construction (ICSSC), by providing the Chair

and Technical Secretariat.

Problem

The National Earthquake Hazard Reduction

Program (NEHRP) established the ICSSC to

assist Federal departments and agencies

develop, improve, and maintain seismic safety

programs for all types of construction. Thirty

Federal departments and agencies currently

participate in the ICSSC. The National

Earthquake Hazard Reduction Act (amended by

Public Law 101-614) designates the director of

NIST, or his deputy, as the chair of the ICSSC.

BFRL provides the Secretariat to the ICSSC

where it facilitates, documents, and

disseminates the work of the committee.

The ICSSC is developing implementation

guidance for Executive Order 12941, Seismic

Safety of Existing Federally Owned or Leased

Buildings. Section 2 of the Order requires all building-owning agencies to develop a seismic

inventory and an estimate of the cost of

achieving adequate seismic safety in their

buildings. The information collected on the

Federal government's half-million owned

buildings will be used to examine potential

rehabilitation programs, and to recommend to

Congress an economically feasible way to

upgrade the seismic safety of the Federal

building population. The ICSSC guidance is aimed at ensuring that the data collected by the

agencies is consistent in content and format, so an effective seismic rehabilitation program,

16
based on reliable and defensible data, will be

proposed to Congress.

Approach

During FY 1996, BFRL serving as the ICSSC

Technical Secretariat, will continue to perform

the day-to-day management of the full corrunittee and the five subcommittees by

organizing and documenting meetings,

maintaining rosters, distributing information.

The ICSSC will encourage consistency of

implementation of EO 12941 by:

1. Developing cost estimating tools and

methodologies. Submitted data will be used

to assess vulnerability of many building

types. The Second Edition - Typical Costs cost

estimating methodology will be adapted for use in subdividing cost estimates into the

cost reporting categories called for in the

ICSSC guidance. Other potential tools and

methodologies that could aid the agencies

will be identified and developed.

2. Holding twice-yearly workshops to provide a forum for agencies to share successes and

difficulties in implementing the order.

Agency personnel will be trained in the use

of the ICSSC-developed methodologies.

3. Providing additional agency-specific

technical support upon request, as explanation, interpretation and/or training in

the use of the ICSSC guidance documents,

distribution of ICSSC documents,

presentations at meetings, review and

comment on proposed methodologies, and

similar efforts.

4. Naming a Database Manager, who will

identify and acquire needed hardware and

software for the government-wide database,

develop the basic framework for the

database, and begin working with agency

personnel to test protocols for transmitting

data.

r

Recent Results

Bieniawski, A., and Todd, D., How To

Suggestions for Implementing Executive Order 12941

on Seismic Safety of Existing Federal Buildings,

NISTIR5770, ICSSC TR17, National Institute

of Standards and Technology, November 1995.

Todd, D., and Bieniawski, A., Editors, ICSSC

Guidance on Implementing Executive Order 12941

on Seismic Safety ofExisting Federally Owned or Leased Buildings, NISTIR 5734, ICSSC RP 5,

National Institute of Standards and

Technology, October 1995.

Todd, D., Seismic Safety ofFederal Buildings -

Initial Program: How Much Will It Cost?, NISTIR

5419, National Institute of Standards and

Technology, April 1994.

Todd, D., Editor, Standards of Seismic Safetyfor

Existing Federally Owned or Leased Buildings,

NISTIR 5382, ICSSC RP 4, National Institute

of Standards and Technology, February 1994.

17
Technical Assistance to FEMA

Project Officer (Existing Buildings)

Technical Assistance to FEMA

Project Officer (New Buildings)

Principal Investigator

Ann Bieniawski

Structures Division

301-975-6065

Sponsor

Federal Emergency Management Agency

Mitigation Directorate

Objective

To provide the technical review of FEMAfunded projects aimed at developing design and

construction guidance documents for seismic

rehabilitation of existing buildings.

Problem

FEMA supplements the capabilities of their

staff by using the technical expertise of BFRL

personnel.

Approach

During FY 1996, BFRL will review statements

of FEMA work and requests for proposals;

participate on proposal evaluation panels, in

advisory panel meetings, in users' workshops,

and selected technical seminars and meetings;

and review draft and final project products,

providing verbal and written comments. During

1996, FEMA requested technical assistance in

the following:

- "Guidelines for Seismic Rehabilitation," and

supporting documentation, being prepared

by BSSaATOASCE;

- "Plan 2005," development of a strategy for

improving seisrruc rehabilitation tools

between 1996 and 2005;

- a homeowner's guide to seismic

rehabilitation; and

- an update of FEMA 1 78, the NEHRP

Handbookfor the Seismic Evaluation of Existing

Buildings.

Recent Results

No published results.

Principal Investigators

U.S. Lew

Structures Division

301-975-6061

Ann Bieniawski

Structures Division

301-975-6065

Sponsor

Federal Emergency Management Agency

Mitigation Directorate

Objective

BFRL will provide technical review of FEMAfunded projects to develop improved building

codes for seismic design of new construction.

Problem

FEMA supplements the capabilities of its staff

by using the BFRL's technical expertise.

Approach

During FY 1996, BFRL will be a member of

mutually agreed upon technical subcomrruttees

of the BSSC ongoing update oi NEHRP

Recommended Provisions for die Development of

Seismic Regulationsfor New Buildings. BFRL will

review all ballot submittals from the Provisions

Update Committee. At the request of the

FEMA Project Officer, BFRL staff will

participate in proposal evaluation panels and

selected technical seminars and meetings.

Recent Results

No published results.

18
Secretariat U.S.-Side Panel on Wind

and Seismic Effects

Principal Investigator

Noel J. Raufaste

BFRL Headquarters

301-975-5905

Sponsor

National Institute of Standards and Technology

and

10 Federal Agency Members

Objective

To provide the U.S. -side Secretariat of the U.S.-

Japan Panel on Wind and Seismic Effects.

Problem

Loss of life and property result from insufficient

knowledge to design adequately and construct

building and other structures cost-effectively

against high winds and seismic loads. Improved

mitigation practices are in early stages of

development. Technical collaborations between

experts in the United States and Japan continue

to produce findings that improve natural hazard

mitigation practices. Such improvements are possible through joint working relations with

experts from the United States and Japan

through performing joint research projects and

exchanges of research personnel, technical data

and information, and research equipment. This

Panel is part of the U.S. -Japan Natural

Resources Development Program operating

under the aegis of the U.S.- Japan Cooperative

Science Program of 1961.

Approach

During FY 1996, BFRL will:

1. Plan U.S. -side activities (18 Agency

membership) through hosting the panel's

Annual Joint Meeting and managing the two

U.S. Panel's domestic meetings.

2. Plan and coordinate technical activities of

the 1 1 Task Committees.

3. Manage U.S. delegation to Japan-side hosted

meetings and workshops and developing

technical programs for U.S. hosted meetings.

4. Develop a draft Panel Home Page

5. Maintain liaison with U.S. and Japan Panel

members and other experts associated with

the Panel's activities.

6. Plan Japan Panel member visits to the

United States under the auspices of the

Panel, e.g., post disaster investigations,

special studies, data gathering.

7. Maintain administrative and technical

records.

8. Prepare and distribute periodic activities

reports, and other materials as appropriate

to U.S. -side Panel and Task Committee

members.

9. Participate in Joint Panel meetings and Task

Committees, and

10. Prepare and publish annual Proceedings.

Recent Results

Proceedings oftJie 27th Joint Panel Meeting on Wind

and Seismic Effects, Technical Memorandum No.

3387, Public Works Research Institute, Japan,

May 1995.

Proceedings of die 6t}t U.S. -Japan Workshop on Earthquake Disaster Prevention for Lifeline Systems,

Public Works Research Institute, Japan, July

1995.

Proceedings of the International Workshop on Wind

and Earthquake Engineeringfor Offshore and Coastal

Facilities, January 17-19, 1995, Public Works

Research Institute, Japan, 1995.

Proceedings of the 10th U.S. -Japan Bridge

Engineering Workshop May 10-11, 1994, Federal

Highway Administration, 1994.

Proceedings of Workshop on Strong Motion Data,

Vol 1 and 2, December 13-17, 1993, Port and

Harbour Research Institute, Japan, 1994.

Proceedings of tite Fourth U.S. -Japan Workshop on

Soil Liquifcation, July 4-6, 1994, Public Works

Research Institute, Japan, July, 1994.

Proceedings of tlie UJNR Tsunami Workshop,

Public Works Research Institute, Japan,

September, 1994.

19
1
STRUCTURES DIVISION

STRUCTURAL

ENGINEERING
ii
Construction Automation

Principal Investigators

William C. Stone

Structures Division

301-975-6076

Lawrence E. Pfeffer

Structures Division

301-975-6067

Sponsor

National Institute of Standards and Technology

Objective

To develop new techniques and standards for

real-time construction metrology and to develop a national standard for kinematic modeling of

construction site machinery and displaying

robust graphical representations which depict

the real time state of the machine to a remote

node on the information superhighway.

Problem

The emergence of high speed computer

communication networks (the "information

superhighway") and the rapid advance of realtime, immersive, computer graphics (virtual

reality) technologies presage the imminent

ability to manage remote construction

machines; and to provide information on the

state of such machines to operators (on-site or remote) that would greatly enhance their

productivity. Limited demonstrations have

been performed on this type of technology,

largely relating to the control of robotic

spacecraft and, more pertinently, to teleoperation of simple machines for handling

nuclear waste.

To achieve acceptance in the construction

industry, a standard means of rapidly

interfacing any piece of machinery to a

construction-site database must be developed.

The underpinning to the above technology is the ability to know the real-time position of any

piece of equipment and component on the

construction site. Present surveying tools suffer

from many shortcomings, the most important is they must operate under line-of-sight (LOS)

conditions. The development of a non-line-ofsight surveying system, which can in effect "see

through walls," represents the "holy grail" of

constructions metrology.

Approach

During FY 1996, BFRL will perform two tasks:

1. Construction Automation Test Bed.

Research will focus on the processing and

display of the real time data returned from

the construction site, relating to the global

position and attitude (6 degrees of freedom)

that define the spatial state of a construction

machine on the surface of the earth, and

appropriate sensor data which provide

information on the state of all other local

degrees of freedom (e.g., the angular rotation

of each joint of a backhoe.) The objective is to allow construction company management

to ascertain, in a visually realistic manner,

the status of the machine and all its key

components in real time from any location

on earth.

Where the proposed work departs from

traditional modeling schemes (e.g., Bechtel's

"Walk Through") BFRL's work animates the

scene. BFRL will realistically model the

change in position of various objects as updated data is received from telemetry uplink. This work will demonstrate (using the

BFRL's tri-directional test facility as the

initial construction site test bed) the ability

to capture position, orientation, and action

and transmit this information to a "remote"

immersion graphics system where an

observer can observe simple actions via

computed tele-presence.

Work will commence on the development of

vehicle representation standards and

software tools to convert existing CAD

models to seamlessly interface with the

proposed standards. The specific technical

approaches in FY 1996 on the establishment

of a Virtual Construction Test bed are as

follows:

Determine key issues concerning the

functionality, interface, and

implementation of a database to serve as a "world model" for

displays/simulation/automation of

construction sites. Develop a short-term.

23
limited function surrogate for the

database to facilitate initial progress on

the virtual construction site simulator.

Investigate how functionalityAnterface

aspects will influence future constructionsite database development. Deterrrune

best strategies to facilitate ease of use with structural data typical of the

construction industry (e.g., existing open

standards {, e.g., STEP} or modifications

of it.) Determine a prototype virtual

construction site simulator/monitor, using

3-dimensional graphics to

display/simulate a construction site. This

system will display a high-fidelity

graphical model of a construction site (or

suitable surrogate), with the position,

orientation, and configuration of the

site's movable objects based on a database-derived kinematic model or, optionally (if available), telemetered

sensor data.

Investigate the currently-available

systems for 3-D relative position sensing over medium and larger workspaces;

current candidates are magnetic,

ultrasonic, optical, and GPS-based

systems. Investigate the use of Global

Positioning System technology for

determining the absolute position and

orientation of parts at construction sites.

Determine the performance of

representative, currently-available GPS

equipment. Determine what technical

approaches/modifications are most

promising to increase differential

accuracy, bandwidth, and robustness to

interference. Gather information to

support cost estimates for developing

improved GPS-based sensing systems.

Determine the feasibility - and most

prorr\ising approaches — for merging GPS

data with alternate metrology techniques

to create a consistent kinematic model of

the site of interest.

Investigate wireless communication

techniques to support the Construction

Automation Project's needs for wireless

telemetry and node-to-node

corrununication; specifically address

bandwidth, interface standards, cost, and

FCC licensing issues. Determine needs

for subsequent research and development.

2. Non-Line-of-Sight Metrology. BFRLwill

expand its work that proved the viability of

NLS technology to effectively "survey

through solid concrete." The results of this

research wdll provide the ability to track

vehicles, construction components, and

personnel inside a building, no matter what

the state of construction. It would permit

the use of a registered-view helmet mounted

display systems for placement of

construction components, or for guiding

repair and retrofit operations. It would

extend to far different fields of endeavor,

including the tracking of firefighters inside a smoke filled building. Work will concentrate

on defining propagation and error

characteristics of spread spectrum radar as a function of material property and class (e.g.,

glass, concrete, wood etc.), frequency

bandwidth, power, signal-to-noise ratio (and

techniques, both physical and analytical for

improving the same), and obstacle geometry

(including thickness, distance from

transmitter to object, and distance from

receiver to object). These data will form the

basis for follow-on work which will permit

investigation of auto-compensation systems

which will account for propagation delays.

Recent Results

Stone, William, C, Ed., NIST Construction

Automation Program Report No. 2: Proceedings of

the NIST Construction Automation Workshop,

March 30-31, 1995, NISTIR5856, National

Institute of Standards and Technology, May

1996.

Stone, William, C, NIST Construction

Automation Program Report No. 1 Non-Line-ofSight (NLS) Construction Metrology, NISTIR

5825, National Institute of Standards and

Technology, February 1996.

24
High-Performance Concrete: Design

and Construction Practices

Principal Investigators

Nicholas J. Carino

Structures Division

301- 975-6063

Dat Duthinh

Structures Division

301-975-4357

Sponsor

National Institute of Standards and Technology

Objective

To enhance the application of high-performance

concrete in the construction of new facilities

and the rehabilitation of existing ones.

Problem

High-strength concrete offers the potential for

cost savings in construction due to reduced

member dimensions, the capability to

accommodate rapid construction schedules, and

enhanced service life. However, from a

structural perspective, high-strength concrete is inherently more brittle than normal strength

concrete. Therefore, failure mechanisms in

structural members need to be understood

before appropriate design criteria can be

developed. Lacking the necessary knowledge,

design codes have taken a conservative

approach and have limited the concrete strength

that can be used to compute member resistance

to tensile failure modes.

Testing is essential to assure that the concrete

delivered to a construction site has the potential

to develop the desired properties. Also, in-place

testing is essential to assure that the finished

product has the specified properties. Standards

for acceptance testing have been developed

based on experiences with normal strength

concrete. Problems have been encountered

when current standards are used to evaluate

high-strength concrete specimens. Laboratories

testing the same material have obtained

divergent strength values, which has resulted in

unnecessary disputes. Testing standards need to

be updated to extend their applicability to highstrength concrete. Developing tools that can be

used in the field to evaluate test results in a

rigorous fashion can promote the use of in-place

tests to determine conformance to performance

requirements.

Current prescriptive curing requirements which

are more than 50 years old, may not be

applicable to high-performance concrete

mixtures. In addition, current standards make

no distinction between curing to obtain

adequate strength and curing to obtain

adequate durability.

The benefits of high-performance concrete are given in CERF Report #94-501 1 HighPerformance Construction Materials and Systems: An

Essential Program for America and Its Infrastructure.

This report, developed by a cooperative effort of

key individuals from industry, academe, and the

Federal government, identifies research related

to high-performance concrete to enhance the

competitiveness of the U.S. construction

industry and reduce the life-cycle costs of

constructed facilities. It notes impediments are preventing exploitation of the unique properties

and advantages of high-performance concrete.

Approach

During FY 1996, BFRL will recognize

improvement of the ACI-3 18 criteria for shear

strength as the first research area related to

structural performance of high-strength

concrete. A state-of-the art report will review

past research, discuss alternative design models,

and propose an experimental research program.

This effort will include a parametric study of

the compression field theory and physical tests. Physical tests will provide the fundamental

information on the post-cracking behavior of

high-strength concrete needed to implement the

compression field theory.

A grant was awarded to Cornell University to

perform a comprehensive review of ACI 318

Standard to identify other design provisions

whose applicability to high-strength concrete is uncertain. The findings will provide a comprehensive research plan on the structural

performance of high-strength concrete. Work

will address test specimen preparation and the

applicability of unbonded caps. Results will be

25
synthesized and developed into

recomnnendations for ASTM Committee C9.

Work will address test specimen preparation

and the applicability of unbonded caps. Results

will be synthesized and developed into

reconunendations for ASTM Committee C9.

Research continues to develop the basis for

updating current ASTM test methods to extend

their applicability to high-strength concrete.

In-place strength tests will be key elements of

performance-based specifications. An

impediment to their widespread use is the lack

of convenient tools that can be used in the field

to analyze test results. A contract was awarded

to Purdue University to develop a user-friendly

computer system to analyze in-place test results.

The system carries out the statistical procedures

previously developed at BFRL. The system will

be presented to ACI Committee 228 for

consideration as a standard practice.

A state-of-the-art report on curing highperformance concrete is being prepared. The

report will include a research plan to provide

the technical basis for recommended curing

practices (or an expert system) for highperformance concretes, that will ensure the

required strength and durability. It is expected

that modeling water diffusion through maturing

concrete will be an important aspect of the

research. Working with BFRL's Building

Materials Division, work will center on

developing a reliable test method to assess the

effects of different curing conditions.

Subsequent experiments will investigate the

effects of curing conditions on the strength and

transport properties. Results will be

synthesized into a suitable form for

presentation to ACI Committees 308, 318, and

363 for incorporation into ACI reports and

standards.

Recent Results

Carino, N.J., Effects of Testing Variables on tJie Measured Compressive Strength of High-Strength

(90 MPa) Concrete, NISTIR 5405, National

Institute of Standards and Technology, October

1994.

Carino, N.J., Guthrie, W.F., Lagergren, E.S.,

and Mullings, CM., "Effects of Testing

Variables on the Strength of High-Strength (90

MPa) Concrete Cylinders," Proceedings of the ACI

International Conference on High-Performance

Concrete, ACI SP-I49, pp. 589-632, November

1994.

26
Fiber Reinforced Polymer Composite

Structures in Construction

Principal Investigator

Dat Duthinh

Structures Division

301-975-4357

Sponsor

National Institute of Standards and Technology

Objective

To characterize the structures built of and/or

strengthened/repaired with Fiber Reinforced

Polymer (FRP) composite materials and to

develop the technical basis for efficient use of

fiber-reinforced polymer composites in

construction.

the literature to determine research needs and

directions. Interaction with staff in BFRL's

Building Materials and Building Environment

Divisions will be pursued. BFRL will contribute

to the development of consensus performance

criteria and design methodology for structures

built of and/or strengthened/repaired with FRP

composites.

Recent Results

New project

Problem

The construction industry is in need of

advanced, high-performance materials to reduce

overall, life-cycle costs of constructed facilities.

While traditional construction materials have

served well, economic pressures in local and

global construction markets have created a

critical need for higher performance materials.

The families of modern FRP composites are advanced and versatile materials which have

many potential applications in the construction

industry. When compared with traditional

materials, composite materials have many

advantages including reduced weight and higher

static and fatigue strength, resistance to

chemicals and corrosion, electromagnetic

transparency, part/member consolidation, low

tooling and finishing costs, wide versatility in

structural form, and low overall life-cycle costs. While FRP composites are being used (or

considered for use) nationwide in a variety of

demonstration projects focusing on bridges,

bridge retrofit, concrete reinforcement, marine

infrastructure, and seismic building upgrades,

several constraints impede widespread

commercialization. One constraint is the lack

of adequate design codes and an incomplete

technical basis from which to develop design

methods.

Approach

During FY 1996, BFRL will conduct a review of

27
High-Performance Steel

Principal Investigator

John L. Gross

Structures Division

301-975-6068

Sponsor

National Institute of Standards and Technology

Objective

To develop the technical basis for new

structural components, connections and

systems that can exploit the advantages of

High-Performance Steel (HPS) and overcome

limitations, and to develop design methods and

specifications for the design of these HPS

systems.

Problem

Design specifications for fabricated steel

buildings and bridges and the hot rolled

structural shapes in use today were developed

when the dominant steel for construction had a

yield strength of 230 MPa. Owng to

refinements in steel-making processes such as rrucro alloying and innovative production

processes, yield strengths in excess of 100 ksi

(690 MPa) may be achieved while favorable

yield-to-ultimate strength ratios and weldability

are maintained.

Current specifications are based explicitly on

material yield strength and ultimate strength.

However, these metrics are not sufficient to

characterize the complete stress-strain behavior

of all steels, and in particular, high-strength

HPS. (The older steels have mechanical postyield properties that are significantly different

those of HPS such as strain hardening behavior

and yield-to-ultimate strength ratio). To

remove this barrier, specifications are required

for the design of steel buildings and bridges

which are based on the complete

characterization of the steel to be employed

thus making design "open" to any

constructional steel which either is, or becomes,

available. Because such an approach would

address not just the yield and ultimate strengths

but rather the complete stress-strain behavior

(yield-to-ultimate ratio, ductility, etc.) it would

provide a consistent level of reliability among

the various steel choices; a condition which is not achieved with current design specifications.

This research specifically addresses priority

research on "Innovative Structural Shapes"

under the "Products and Systems" research

topic and "Advanced Analysis Methods" under

the "Analysis and Design" research topics as identified in Materials for Tomorrow's

Infrastructure: A Ten-Year Plan for Deploying HighPerformance Construction Materials and Systems.

Civil Engineering Research Foundation.

Approach

During FY 1996, BFRL will perform five tasks:

1. Ascertain the applicability of current design

specifications to HPS.

2. Identify and quantify the characteristics of

currently available steel sections that

contribute to premature failure (e.g., local

instability).

3. Study analytically the performance of

sections optimized for superior performance

with HPS.

4. Verify experimentally the performance of

sections fabricated/rolled from HPS and

ability to analytical predict the performance.

5. Develop the technical basis for highperformance steel design and construction

standards.

The application of HPS will be driven by its high strength, toughness and weldability but

potential obstacles must be overcome to use HPS fully. Local and/or overall instability may

prevent a lighter and more slender HPS member

from achieving its yield strength or may

significantly reduce its inelastic rotation

capacity after yielding. New cross-section

shapes optimized for superior performance with

HPS steels are required.

Recent Results

New project

28
Fire Resistance of High-Strength

Concrete

Principal Investigators

LT. Phan

Structures Division

301-975-6077

Dat Duthinh

Structures Division

301-975-4357

Sponsor

National Institute of Standards and

Technology

Objective

To gain an understanding of the performance of

high-strength concrete (HSC) when exposed to

high temperatures as would occur during fires.

Problem

HSC is gaining in use in structural applications,

such as columns of high-rise buildings, in

prestressed concrete members, and in offshore

structures. However, little is known about the

fundamental behavior of HSC when exposed to a fire. A few tests have indicated an alarming

tendency for explosive Spalding of structural

members under fire conditions. The current

belief is that the poor performance is due to the

extremely low porosity of the cement paste that

prevents the escape of steam, leading to high

internal pressures that spall the concrete. To

assure life safety, understanding the fire

endurance of HSC is essential. This research

topic is listed in CERF Report 94-50 1 1

, which

outlines the 10-year plan for research on highperformance construction materials and systems

(HPCMS).

Approach

During FY 1996, BFRL will prepare a state-ofthe-art report to document past and ongoing

studies on the fire resistance of HSC. The

report will include a review of the various

damage mechanisms, including the role of

moisture transport, when concrete is exposed to

fire. In addition, techniques developed to

model and predict fire damage to concrete will

be reviewed. If suitable modeling tools are

available, they will be used for initial parametric

studies to gain insight into the factors that

control performance during fire exposure. Such

insight will be useful to develop a comprehensive long-term research program to

understand the damage mechanism(s) when

HSC is exposed to fire. Since this is a multidisciplinary project, the Pi's will interact with

appropriate experts in BFRL's Building

Materials, Building Environment, and Fire

Safety and Engineering Divisions to formulate

the research program. It is envisioned that,

once a test-calibrated model of the fire

resistance of HSC is formulated, such model

can be implemented as a module of a computer

program to assess the global resistance of an HSC structure to fire. One computer program

which might serve as the platform for the model

is the program SAFIR, currently under

development at the University of Liege,

Belgium.

Following the completion of the state-of-the-art

report, an experimental program will be

planned. The objectives of this test program are

to: 1. obtain first hand a basic understanding of

the performance of HSC when subjected to

elevated temperature at a high rate; and 2.

validate (or refute) observations and findings in

other studies. This test program will be planned

and conducted in collaboration with BFRL's

Fire Safety Engineering Division. The findings

from this initial test program will be used, with

information obtained from the state-of-the-art

report, in developing more comprehensive,

future research plans for this project.

Recent Results

New project

29
Next Generation Design Standard

for Wind Loads

Principal Investigator

Emil Simiu

Structures Division

301-975-6076

Sponsor

National Institute of Standards and Technology

Objective

To develop key elements of an improved wdnd

load design standard that \v\\\ use existing

databases and state-of-the-art computational

methods for establishing site-specific design

wind speeds and the corresponding steady and

fluctuating structural loads.

Problem

There are many significant deficiencies in the

wind load design provisions of current U.S.

codes and standards. They include: 1. extreme

wind speeds and corresponding load factors

derived from outmoded estimation methods;

2. exposure coefficients that cannot deal with

complex wind exposures (the normal case);

3. gross simplifications of extreme pressures and

loads that ignore the directional effects of wind;

and 4. no distinction between design for safety

and design for serviceability.

Besides the reliable estimation of design loads,

there is an urgent need for improved methods

by which to assess wind speeds, and thus the

wind forces, in complex wind exposures

following extreme events such as hurricanes.

Only then is it possible to evaluate with

reasonable confidence the performance of

structures subjected to wind loads approaching

or exceeding the design limit states.

Approach

During FY 1996, BFRLwill:

1. Provide the application of the "peaks over threshold" extreme value estimation

approach to hurricane winds and

2. Develop a framework for interactive

standard provisions using climatological and

aerodynamical databases.

This work will combine directional extremes for

a given site with wind tunnel databases for force

and pressure coefficients that most closely

matches the geometry and/or dynamic

characteristics of the structure. Of major

interest is the tail length of distributions that

best fit a given set of annual extreme wind

speeds. The widely used Gumbel distribution

has an infinite tail length while physical

grounds require that wind speeds be bounded.

Recently, statistical methods for estimating

those bounds have become available. In

complex wind exposures, analytical models

based on fundamental principles of fluid

mechanics and on certain empirical

relationships offer a substantial improvement

over current equilibrium boundary layer models

on which site-specific wind speeds are based.

Since force and pressure coefficients are direction-dependent, directional distributions of

extreme wind speeds can be handled most

conveniently in combination with these

coefficients. Finally, the development of

reliability concepts will make it possible to

match safety and serviceability criteria with

given levels of risk under wind loading.

Recent Results

Simiu, E and Stathopoulos, T., "Codification of

Wind Loads on Buildings Using Bluff Body

Aerodynamics and Climatological Data Bases,"

Proceedings, 3rd International Colloquium on Bluff

Body Aerodynamics and Application , Virginia

Polytechnic Institute and State University, July

1996.

Simiu, E., and Heckert, N.A., Extreme Wind

distribution Tails: 'Peaks Over Tlireshold' Approach,

NIST Building Science Series 174, National

Institute of Standards and Technology, March

1995 and Journal of Structural Engineering,

Vol.122, pp539-547, May 1996.

Whalen, T.M., Probabilistic Estimates of Design

Load Factors for Wind-Sensitive Structures Using the

'Peaks Over Tlireshold' Approach, Technical Note

1418, National Institute of Standards and

Technology, April 1996.

Simiu. E., Heckert, N.A., and Whalen, T.M.,

Estimates of Hurricane Wind Speeds by the 'Peaks

Over Tlireshold' Method, Technical Note 1416,

National Institute of Standards and

30
Technology, February 1996.

Schechter, M.M., Schechter, E., and Simiu, E.,

Developmental Computer Version ofASCE 7-95

Standard Provisions for Wind Loads, NIST

Technical Note 1415, National Institute of

Standards and Technology, November 1995.

Assessment of Tubular Steel Joints

in Existing Offshore Structures

Principal Investigator

Andrew Taylor

Structures Division

301-975-6078

Sponsor

Department of Interior

Minerals Management Service

Technology Assessment and Research Branch

Objective

To conduct a workshop for assessing the state- of-the-art and future research needs related to

tubular steel joints in offshore structures.

Problem

About 3800 offshore platforms are operating in

the Gulf of Mexico. Many of these are in

shallow water, and constructed more than 40

years ago. Most of these platforms are still productive. However, the code-specified design

level wave heights have increased dramatically

since the time when the platforms were

designed and constructed. Consequently, these

older platforms are significantly under-designed

by today's standards. More recently, several

major platforms have been constructed off the

West Coast of the United States. These

platforms are in zones of high seismicity, and

may be subjected to severe earthquake loads.

Very little is known about the cyclic inelastic

behavior of joints in offshore platforms

subjected to either extreme storms or to

earthquakes.

When under-designed platforms are exposed to

extreme loadings during a storm or earthquake,

they can undergo several cycles of inelastic

deformation. These deformations may not be

large enough to cause immediate failure of a

joint or frame, but the cumulative effect of

plastic deformations caused by a series of

moderate storms or earthquakes over many

years may eventually lead to failure. What is the remaining service life of these structures

which experienced one or more damaging

storms or earthquakes?

31
Recently implemented Federal regulations have

prompted reexamination of many existing

offshore platforms. Under Minerals

Management Service (MMS) policies, offshore

platforms must periodically be re-certified as to

their safety and capacity. Petroleum production

companies increasingly have found it difficult to

re-certify older platforms because there is a lack

of laboratory test data and analytical methods

available to verify platform capacity under

inelastic cyclic loading. As a result, older

platforms must sometimes be decommissioned

and removed - an extremely costly procedure.

Approach

During FY 1996, BFRLwill prepare a summary

report containing the papers presented at its workshop, Houston during 5-6 September

1995, to define the state-of-the-art, and to

identify research needs, for tubular steel joints

in offshore structures subject to high amplitude

cyclic loading. The workshop focused on issues

relating to requalification of existing offshore

structures. Approximately 30 representatives of

the petroleum industry, research institutes and

universities attended. The summary of the

report will contain the discussions and

conclusions reached at the workshop.

Recent Results

New project

32
BUILDING MATERIALS

DIVISION

COATINGS AND OTHER

MATERIALS
I
Coatings Service Life Prediction

Consortium

Principal Investigator

Jonathan Martin

Building Materials Division

301- 975-6717

Sponsor

National Institute of Standards and Technology

Objective

To demonstrate and validate methods that

mathematically predict and relate the

photodegradation response of coating systems

exposed to UV-radiation in the laboratory and

field, for quantitatively characterizing the

photodegradation response, and modeling

temporal changes in solar spectral radiation.

Problem

UV-radiation, wetness and temperature of a

material, are considered the prime weathering

factors in determining the service life of coating

systems exposed outdoors in most nonindustrial environments. The inability to

control or adequately characterize temporal

changes in these weathering factors is a major

challenge to overcome before establishing a connection between the degradation response of

polymeric materials exposed in the laboratory

and the field. Needed is the correlation

between degradation effects of UV-radiation in

the field and in the laboratory.

Approach

During FY 1996, BFRL will quantify

photodegradation effects of uv-radiation in the

field and laboratory. The work will be

performed at a consortium member laboratory.

A model was identified and further refined for

mathematically relating photodegradation

results obtained from field and laboratory

exposure experiments. This model requires

knowledge of a material's spectral UVabsorbency and its spectral quantum yield along

with knowledge of the spectral UV-irradiance to

which it is exposed.

This research will be extended to include all photolytically active wavelengths such as modeling spectral UV-radiation - time series

and other mathematical models for modeling

temporal changes in the solar spectral UVradiation and determining the number of

spectral wavelengths to model the photolytically

active wavelengths between 290 nm and 325

nm. Photolytically active wavelengths will be

determined from spectral quantum yield

experiments performed in the laboratory. Key

questions will include the range of wavelengths

over which quantum yield response is positive,

the number of wavelengths required fully to

specify the absorption and quantum yield

spectra, and the effect of experimental error of

filters having different half-widths. The validity

of the proposed model will be learned by

exposing the same coatings in the field and

laboratory and comparing the results. In this

experiment, the field exposure sites will be

equipped with a spectral filter radiometer while

the spectral quantum yields and absorption

spectra vdll be determined in the laboratory.

Recent Results

Floyd, F.L. and Martin, J.W., "Influence of

Reliability Theory on R&D Planning and

Management of Risk," Farbe und Lack, V. 102,

p28, 1996.

Frohnsdorff, G.J. and Martin, J.W., "Toward

Prediction of Building Service Life-The

Standards Imperative," Proceedings oftJie 7th

International Conference on the Durability of

Building Materials and Components, Stockholm,

Sweden, May 1996.

Martin, J.W., Saunders, S.C., Floyd, F.L, and

Wineburg, J., "Methodologies for Predicting

Service Lives of Coating Systems," Federation of

Societies of Coatings Technology Monograph Series,

1996.

Nguyen, T. and Martin, J.W., "Modes and

Mechanisms of Degradation of Epoxy-coated

Reinforcing Steel in a Marine Environment,"

Proceedings of the 7th International Conference on the

Durability ofBuilding Materials and Components,

Stockholm, Sweden, May 1996.

35
Integrated Knowledge System for

Corrosion-Protective Coatings for

High-Performance Steel

Principal Investigators

Lawrence Kaetzel

Building Materials Division

301-975-5912

Mary McKnight

Building Materials Division

301-975-6714

Sponsor

National Institute of Standards and Technology

Objective

To develop an architecture, standard knowledge

formats, information model, and operational

computerized systems for representing and

disseminating organic coatings knowledge for

protecting high-performance steel structures

against corrosion.

Problem

Coatings provide a versatile, cost-effective

means for protecting steel structures against

adverse environmental conditions, but decisions

about coating system selection are often

difficult to make. Currently, users of coating

systems must rely on information represented in

many different forms and systems. These

include manuals, guides, photographs and

drawings, videos, databases, and other

references. In addition, a human expert's advice

may be necessary to reach a decision. Often,

the decision-making knowledge may be

dispersed or unavailable. Currently, no

comprehensive systems define these entities and

address high performance construction

materials. An integrated knowledge system that

includes different forms of knowledge and is presented in a coherent format will improve the

specification, selection, and use of coatings

systems for protecting steel, thus improving the

performance and extending the service life of

structures.

Approach

During ¥Y 1996, BFRL will 1. distribute its Coatings Expert Advisory (COEX-I) expert

system to coatings industry users, 2. develop

database formats for representing the properties

of coatings formulation and performance

characterization, and 3. investigate and test the

application of intelligent agent technologies for

enhancing the exchange of coatings knowledge

between industry and government

organizations. BFRL will develop an improved

decision-making process and a repository of

knowledge for use by the construction industry

that help extend the service life of these

structures. The work in developing an

Integrated Knowledge Based System include

defining and establishing an architecture,

information model, and developing

computerized prototypes and operational

systems. Initially, the domain and audience will

be narrowly focused, then expanded to address

more comprehensive (deep knowledge) systems

for multi-disciplines (e.g., material suppliers,

designers). For example, COEX-I contains

knowledge on the failure, remedial action, and

selection of coatings systems for stationary,

military structures (including steel substrates).

The system integrates multiple forms of

knowledge, including high-level expert

reasoning, audio/video, databases, photographs,

and bibliographic references. Eventually, this

system could be expanded to address additional

structure types (e.g., bridge management

systems for highway structures).

The COEX-I expert system developed in 1995

will be distributed to coatings industry users for

their review and response during 1996. In

1996, two new methods will be evaluated, and

tested for their application to the coatings

knowledge domain: 1. development of a database format to represent properties of

coatings materials and data sets from laboratory

and field tests on performance, and 2. automated techniques for the exchange of

knowledge between humans and computers.

BFRL has developed a draft database format

that will be submitted to the Steel Structures

Painting Council for refinement and possible

adoption as a standard. Since databases are a valuable form of coatings knowledge, this

activity should promote a greater exchange of

knowledge and provide a basis for computercomputer knowledge transfer. An example of

36
their importance, is demonstrated by the need

to determine the effects of solar UV-B radiation

on coatings performance where a database is being developed under a separate project from

the NIST Standard Reference Data Program

(SRDP).

New methods for improved dissemination and

access to knowledge bases will be investigated,

including the development of intelligent agents

that allow more efficient computer-computer

and human-computer interactions. A testbed

(computerized system and software

development tools) will be established at BFRL

that will provide a platform for developing and

testing intelligent agents, and database servers. The testbed will be accessible through highspeed data links to other organizations

including the University of Kansas, NIST's

Physics Laboratory, Steel Structures Painting

Council, and the Infrastructure Technology

Institute at Northwestern University.

Standards activities such as STEP, Electronic

Data Exchange (EDI), Knowledge Query

Language (KQML) will be evaluated and

implemented if they apply.

Recent Results

Developed an information model and

architecture for coating materials databases and

installed on an Internet World Wide Web site.

Its address is http://ciks.cbt.nist.gov

Established an SSPC Working Group -

Committee C.4.10 on Knowledge Based

Systems for Coatings.

Database Architectures for the

Properties of Construction Materials

Principal Investigators

Lawrence J. Kaetzel

Building Materials Division

301-975-5912

Mary E. McKnight

Building Materials Division

301-975-6714

Sponsor

National Institute of Standards and Technology

Objective

To demonstrate the use of a database

architecture for representing and exchanging

material properties data for coatings and

cementitious materials.

Problem

There is a lack of consistency in the formats and

procedures used to represent and exchange

materials properties database information

among construction industry users. This results

in difficulties when attempting to characterize

the performance of materials and comparing the

results from laboratory and field tests, or simply

in the exchange of information electronically.

The problems are manifested by the fact that

database development efforts are: 1 ) biased by

the originator, 2) software and hardware

platforms are inconsistent, and 3) there is an

absence of the use of information standards.

These situations result in a less-than-optimal

level of decision-making, due in part, to the

absence of relevant data.

Approach

During FY 1996, BFRL will establish, test, and

demonstrate databases using the following

methods and activities:

1. develop standard formats for representing

the properties of coating materials and

cementitious materials,

2. apply the ISO Standard 9579, Remote Data

Access (RDA), generic model to construction

industry information needs, and

3. develop and implement database

information using the ANSI Standard

37
X3. 135.992, SQL Relational Database

Model.

Performance Criteria for Enclosures

for Lead-Based Paint

The tasks will rely on using BFRL's National

Computer-Integrated Knowledge System

Network (CIKS) test bed for implementing and

testing data sets against the architecture. The

Internet World Wide Web framework will be

used as the point of access to the database.

Success in developing a model architecture will

be determined, largely by the application of

many test data sets of various types and

sources. Currently, the test results from the

AASHTO Materials Reference Laboratory

(AMRL), Paint Proficiency Program and the

ASTM Cement and Concrete Reference

Laboratory (CCRL) are being evaluated for

implementation. Tools will be developed so

that the feasibility and usefulness of the

database formats can then be judged by a user base from industry and government, through

access provided by the NIST CIKS test bed.

This will provide the basis for a non-proprietary

architecture that can be implemented within

the construction industry materials user communities, and one that is based on

information standards. Examples of additional

data sets include material product data sheets

and safety data sheets on coating materials.

These will be provided by coating

manufacturers and suppliers.

Recent Results

New project

Principal Investigators

Walter Rossiter

Building Materials Division

301-975 -6719

Mary McKnight

Building Materials Division

301-975-6714

Sponsor

U.S. Department of Housing and Urban

Development

Office of Lead-Based Paint Abatement and

Prevention Poisoning

Objective

To develop preliminary performance criteria for

mechanically attached enclosures for lead-based

paint on interior and exterior walls of housing.

Problem

The U.S. Department of Housing and Urban

Development (HUD) concluded from the

results of a demonstration project that liquidapplied encapsulant may be less expensive in

abating lead-based paint hazards than

mechanically attached enclosures. Situations

may arise, however, where enclosures are more

appropriate than encapsulation. Presently, no

suitable, generally accepted performance criteria

exist for the selection or assessment of enclosure

materials. HUD has requested BFRL to prepare

the needed criteria on an emergency basis.

Approach

During FY 1996, BFRL will identify

performance requirements and test procedures

for mechanically attached enclosure materials

applied to interior and exterior walls.

Preliminary performance criteria will be

developed based primarily on current

knowledge and secondarily on short-term tests.

This criteria will address enclosure

characteristics that are effective in keeping the

lead in place and to keep contamination of the

environment at a very low risk for the desired

time. Additionally, the criteria will address

38
safety characteristics such as resistance to fire as

defir\ed by codes or other regulations.

Research will focus on the mechanical and

physical properties of enclosure materials and

components. Included are enclosure characteristics that prevent the release of lead-contaminated particles (e.g., structural integrity,

abrasion resistance, and impact resistance), and

characteristics associated with health and safety

(e.g., fire resistance). BFRL will:

1. Identify performance attributes and requirements for enclosure materials and systems,

2. Review literature to develop a current

knowledge database,

3. Develop the preliminary performance criteria

based on current knowledge,

4. Identify gaps in the knowledge base,

5. Conduct tests, as necessary, to fill the gaps

in the knowledge base, and

6. Revise the preliminary performance criteria

based on the test results.

ASTM standards will be used where applicable

as testing is done. The tests will address

mechanical and physical properties associated

with the effectiveness of the enclosure materials

and systems in forming a barrier against the

escape of lead-contaminated particles. BFRL

also will address the efficiency of the enclosure

to prevent the release of lead-contaminated

particles through gaps and cracks in the

mechanically attached enclosure due to air

movement.

During the study, sites will be visited where

leaded-paint surfaces have been enclosed or where the installation of enclosures is being

considered. The visits will be to assess properties of surfaces being considered for

encapsulation and to gain first-hand knowledge

about the suitability of commonly used

enclosure materials and systems.

Results will be provided to ASTM E06.23 to use in the development of standards for

enclosure materials and systems.

Recent Results

New project

Performance Criteria for Selection of

Liquid-Coating Encapsulant for

Lead-Based Paint

Principal Investigators

Walter Rossiter

Building Materials Division

301-975-6719

Mary McICnight

Building Materials Division

301-975-6714

Sponsor

U.S. Department of Housing and Urban

Development

Office of Lead-Based Paint Abatement and

Poisoning Prevention

Objectives

To develop preliminary performance criteria for

liquid-coating encapsulant for lead-based paint.

Problem

In a survey of the nation's housing, the U.S.

Department of Housing and Urban Development (HUD) found that about 57 million

homes in the United States have lead-based

paint (LBP) on at least one painted surface.

One way of helping to ensure that the hazards

of LBP in housing are kept low is to protect the

paint by a liquid-coating encapsulant. A major

deterrent to the use of these encapsulant is the

lack of performance standards and field

performance data.

Approach

During FY 1996, BFRL will develop preliminary

performance criteria based on early age or shortterm laboratory and field tests. This work

involves identifying performance requirements

and test procedures. On the most general

performance level, encapsulant must, with an

acceptable probability, ensure that the

encapsulant keeps the lead in place and

prevents it from contaminating the

environment for the desired time. The

performance criteria must address encapsulant

material characteristics that prevent release of

lead such as abrasion resistance, impact

resistance, leaching resistance and ability to

39
prevent failure (e.g., peeling, flaking and

chipping) of the underlying LBP layer.

BFRLwill:

1. Visit several field sites where encapsulant

have been installed or are being considered

for use to identify specific requirements and

select test materials.

2. Select substrate test materials and develop

procedures for preparing them in a uniform

and consistent manner to simulate

conditions expected in the field.

3. Select encapsulant and control paints to use

in testing.

4. Select appropriate test procedures using

ASTM tests where appropriate and prepare

test specimens.

5. Subject specimens to laboratory performance

tests under conditions in which the applied

stresses are at the high ends of the ranges

expected under service conditions.

6. Based upon the results of the laboratory

tests, carry out limited field testing. Using

both data sets, preliminary performance

criteria will be developed.

Results of the research will be provided to

ASTM Committee E06.23, Abatement of

hazards from Lead in Buildings, to use in

improving the technical bases for standards for

encapsulant. Following this work, BFRL will

address long-term laboratory aging and

weathering tests and additional field tests to

provide data for verifying and improving the

preliminary performance criteria.

Recent Results

New project

Method for Evaluation of

Performance of Lead-in-Paint

Measuring Devices Under Simulated

Field Conditions

Principal Investigator

Mary McKnight

Building Materials Division

301-975-6714

Sponsor

U.S. Department of Housing and Urban

Development

Office of Lead-Based Paint Abatement and

Poisoning Prevention

Objectives

To identify and quantify factors affecting the

field performance of portable x-ray fluorescence

(XRF) measurements of lead in paint and

develop a laboratory test method for evaluating

portable XRF devices.

Problem

Recent legislation (Housing and Community

Development Act of 1992, PL102-550) will

phase in requirements for lead-based paint

testing for all housing built before 1978. These

requirements are expected to result in several

new x-ray fluorescence (XRF) devices. Because

of health and financial liabilities are associated

with these measurements, having reliable

estimates of the field performance parameters of

the measurements are essential (e.g., detection

limits, precision, bias). For some XRF devices,

research results have shown that estimates of

these performance parameters obtained using

existing laboratory evaluation procedures do not

agree with estimates obtained using fieldacquired data. Currently, field studies are used

to characterize additional devices. However,

field studies are limited in several ways - sites

having parameters in the necessary ranges are

difficult to find; systematic variation of the

parameters is usually not possible; implementation of new technologies may be impeded; and advances in the fundamental

understanding of a measurement procedure are

limited. Thus, there is a need for a laboratorybased field-simulation test protocol for the

reliable evaluation of portable XRF devices

40
which will overcome these limitations.

Approach

During FY 1996, BFRL will:

1. Characterize and model the scientific principles controlling the performance of portable

XRF device. A mathematical model

embodying a fundamental understanding of

the measurement process and the effects of

the composition and configuration of a test specimen upon the measurement response

will be developed. First, a conceptual model

of the measurement process will be

constructed to portray the scientific principles involved, factors likely to affect

instrument response, and characterization of

typical field situations about these factors.

Second, a mathematical model based on the

conceptual model will be developed. The

mathematical model will be used throughout

the study to explore the implications of

various material configurations and field

conditions on instrument response and to

aid interpretation of experimental results.

2. Design and carry out laboratory experiments

to simulate significant field conditions, as determined by modeling, and perform a

limited field study to decide whether the

laboratory results are consistent with field

results. Using information obtained from

the literature and other sources, and from

the model, a simulated field study and an

actual field study will be statistically

designed. The design for the laboratorybased field simulation study will include use

of model wall sections each about one-meter

square containing materials in configurations

typical of those found in residential

buildings. The laboratory experiment will be

performed in a room with temperature and

humidity controls that allow the conditions

to be changed as needed. Field experiments

will be conducted to determine whether the

estimates of measurement variability

obtained in the laboratory and field are consistent with each other.

3. Upon completion of the study, BFRL will

write a draft standard test method for the

laboratory-based evaluation of portable XRF

devices and present it to ASTM Committee

E06.23, Abatement of Hazards from Lead in

Buildings, for standardization.

Recent Results

Developed mathematical model for predicting

effects of wall materials and configurations on

XRF instrument response.

41
Factors Affecting the Leaching of

Lead from Lead-Based Paint Films

Principal Investigators

Eric Byrd

Building Materials Division

301-975-5866

Mary McKnight

Building Materials Division

301-975-6714

Sponsor

U.S. Department of Housing and Urban

Development

Office of Lead-Based paint Abatement and

Poisoning Prevention

Objective

To determine the relative importance of pH,

acid type, acid concentration, surfactant

concentration, lead concentration and

immersion time on the leaching of lead from

lead-based paint films and to recommend

encapsulant performance requirements to

ASTM E06.23 for encapsulation specifications.

Problem

According to a recent U.S. Department of

Housing and Urban Development (HUD)

report to Congress, an estimated 57 million

homes in the United States contain lead-based

paint. Painting the lead-based paint with an

encapsulant may abate the hazards of leadbased paint. However, questions remain about

what conditions lead is leached from a leadbased paint film and transported through an

encapsulant film. Previous HUD-sponsored

BFRL research results showed that essentially

no lead is leached from lead-based paint

immersed in dilute nitric acid (pH 2 or pH 4) or from paint immersed in pH 10 or 12 sodium or ammonium hydroxide solutions. On the other

hand, practically all the lead was leached from

paint immersed in 20 percent acetic acid, while

a much smaller amount was leached from a 5

percent acetic acid vinegar. These results show

that leaching of lead depends greatly upon the

type and concentration of acid to which the

lead-based paint is exposed. The leaching effects

of other acids and household cleaners could

leach lead.

Approach

During FY 1996, BFRL will evaluate paint

having a lead content of approximately 60

percent by mass of non-volatile components.

The research consists of three tasks:

1. Conduct a two level, fractional, factorial

experiment to determine the relative

importance of pH, acid type, acid

concentration, surfactant concentration, lead

concentration and immersion time on the

leaching of lead from lead-based paint films.

2. Perform investigation of other factors

depending on task 1 results.

3. Determine the transport of lead through

three encapsulants for at least two exposure

conditions that cause lead leaching from

lead-based paint films. Exposure conditions

will be selected in consultation with

members of ASTM Committee E06.23,

Abatement of Hazards from Lead in Paint,

and HUD.

Recent Results

New project

42
Managing Lead-Related Hazards in

Housing

Technical Assistance on Lead-Based

Paint Issues

Principal Investigator

Mary McKnight

Building Materials Division

301-975-6714

Principal Investigator

Mary McKnight

Building Materials Division

301-975-6714

Sponsor

U.S. Department of Army

The Corps of Engineers

Construction Engineering Research Laboratory

Objective

To organize DoD/Federal Agency Task Force

Meetings and provide technical assistance to

solve lead-related coating problems that meet

regulations.

Problem

Several practices have led to potentially

hazardous levels of lead in and around military

family housing, including the use of leaded

paints, lead in gasoline and the presence of

firing ranges. Because of the hazards associated

with exposure to leaded materials (dust, paint,

soil, and air particulate), there is a need for the

DoD and other government agencies to

coordinate policy, abatement and control

procedures and guidance.

Approach

During FY 1996, BFRL will continue to plan,

organize and co-chair the Task Force Meetings

regularly bringing together DoD experts

involved in environmental, health and

engineering areas and other government

agencies to support development of policy,

procedures, and guidance.

Recent Results

New project

Sponsor

U.S. Department of Housing and Urban

Development

Office of Lead-based paint Abatement and

Poisoning Prevention

Objectives

To provide technical assistance on lead-based

paint material-related issues and measurement

procedures and Chair ASTM E06.23

Committee to develop consensus standards for

abatement of lead hazards in buildings.

Problem

The Office of Lead-Based Paint Abatement and

Poisoning Prevention, of the U.S. Department

of Housing and Urban Development (HUD)

receives many requests for technical assistance

on issues about abatement of hazards from leadbased paint in housing. Some of these requests concern material properties and performance of

paints and coatings and material-related

measurement procedures. HUD needs an

overall consensus standard practice for abating

hazards from lead in buildings and related

structures that would include assessment and

analysis of the problem, design of abatement

strategy, abatement procedures and postabatement management procedures.

Approach

During FY 1996, BFRL will provide technical

assistance on topics relating to the performance

of paints and coatings, the abatement of

hazards from lead-based paint, measurement of

lead concentrations in paint films, and other

material-related issues. BFRL also will provide

leadership to develop the consensus standards

needed for abating hazards from lead in

buildings by chairing the ASTM subcommittee

formed to address this need.

43
Recent Results

Provided technical assistance to HUD on the

1995 revision of HUD's guidelines for

abatement of lead hazards in housing and EPA's

risk assessor training manual.

Developed under NIST leadership, ASTM

^06.23, Abatement of Hazardsfrom Lead in

Buildings, 13 full consensus standards and 5

provisional standards.

Performance of Tape-Bonded Seams

in Elastomeric Roofing Membranes

Principal Investigator

Walter Rossiter

Building Materials Division

301-975-6719

Sponsor

National Institute of Standards and Technology

Objective

To investigate the rheological properties of

EPDM roofing seams bonded with butyl-based

tapes and to compare their performance against

seams bonded with liquid-applied adhesives.

Problem

EPDM is a non-polar material and, as such, it has excellent weathering properties, but care must be taken in adhesively bonding EPDM

with itself, as required in the formation of a

roofing seam. Liquid-applied butyl adhesives

have excellent weathering properties, and have

been extensively and successfully used in

forming EPDM roofing seams since the mid1980s. However, liquid-applied adhesives

contain a large volumetric fraction of solvents,

which are increasingly becoming

environmentally unacceptable. A replacement

for these liquid-applied adhesives is butyl-based

tapes. Users of EPDM roofing such as contractors and consultants have expressed concern that the rheological properties are properly evaluated and data be developed to

characterize the rheological performance.

Approach

During FY 1996, BFRL will investigate the

effect of various application variables and

environmental factors on the rheological

performance of butyl-tape systems. BFRL will

expand its FY 1995 laboratory experiments to

investigate the effect of a load on rheological

performance by investigating the effect of

application variables and environmental factors.

These experiments will include temperature,

pressure, rubber surface condition, and tape

thickness. The research is primarily laboratorybased, statistically designed experiments

complemented by field investigations. In the

44
field, roofs will be inspected and tape-bonded

seam samples will be obtained. Mechanical

properties of the field seam specimens will be

determined and compared with those of liquidadhesive bonded seams. In the laboratory, the

experimentation will focus on subjecting tapebonded EPDM seam specimens to testing of the

Theological performance under a range of

application and environmental conditions. The

seam specimens will be prepared using

currently available EPDM membrane material

and tape/primer systems. Additionally, seam

specimens fabricated with a solvent-based butyl

adhesive will be prepared as controls and

included in some experiments.

The technical approach has been developed in

concert with the roofing industry and

government agencies having large inventories of

buildings. The outcome of this collaborative

effort is a CRADA between industry and

government. Eight collaborators are participating including three manufacturers of

EPDM roofing, two manufacturers of seam

tapes, two trade associations, and one

Department of Defense agency. The results of

the investigation will form the basis of the

development of a test protocol and recommended criteria for evaluating the long-term performance of tape-bonded seams in EPDM roofing

membranes.

Recent Results

Rossi ter, W. J., Lechner, J. A., Seiler, J. P., and

Embree, E., "Performance of Tape-Bonded

Seams of EPDM Membranes: Initial

Characterization," 11th NIST/NRCA

Conference on Roofing Technology, National

Roofing Contractors Association, 1995.

International Standards for Design

Life of Buildings

Principal Investigator

Geoffrey Frohnsdorff

Building Environment Division

301-975-6706

Sponsors

National Institute of Standards and Technology

The British Standards Institute, United

Kingdom

Commonwealth Scientific and Industrial

Research Organization, Australia

Objective

To develop international standards that assure the designed life of a building under anticipated

environmental actions will be achieved, and to

provide a basis for maintenance management.

Problem

As building technology advances, there is an

increasingly strong desire to reduce the risks

associated with innovation, whether due to

premature deterioration resulting from the

materials and components used, or the way they

are incorporated into the building design. In a

partial response to the need, standard methods

for assessing the service life of individual

materials and components have been developed

in ASTM Committee E06, "Performance of

Buildings." Now, methodologies for assessing

the service life of individual materials and

components are to be incorporated into a methodology for assessing whether a building of a given design will perform satisfactorily over its intended life, the service life. The standard is needed to provide guidance to: designers and

planners on methods for assessing the expected

life of a building and assuring that its design life

will be met; construction engineers on how to

construct a building to assure the intended life; materials and product manufacturers on

information they should provide to assist

assessment of the life of a building;

maintenance engineers and building owners on

information they will need to carry out the

maintenance required to achieve the design life;

45
and standards and code bodies and legislators

on the need for improved standards and codes.

To prepare the standard, ISO Technical

Committee 59, Building Construction, established a Working Group (WG9) on the Design Life of

Buildings, with ASTM Committee E06,

Performance of Buildings, as the Convener. The

new WG was the result of a request made by

ASTM E06, Performance of Buildings , through

ANSI to ISO TC59. The WG has members

from Australia, Canada, Denmark, Finland,

Israel, Italy, Japan, the Netherlands, Norway,

Sweden, the United Kingdom, and the United

States. To advise the Convener on the U.S.

position, ASTM E06 set up a U.S. TAG

(Technical Advisory Group) which the

Convener chairs. An executive committee has

been established in the WG to plan the WG's

work between its annual meetings.

Approach

During FY 1996, BFRL researchers will be

working with the WG to develop a guide for

Planning of and Managementfor, Service Life of

Buildings. Its scope will be limited to the

building envelope, partitions and surface

finishes. British, Canadian, and Japanese

documents on service life planning of buildings

will be used as working documents. Building

services and mechanical equipment will not be

included in the first version, though the

principles described will be applicable to them;

it is intended to include them in a later version

of the standard. As far as possible, the standard

will be based on materials science, but, until the

materials science basis is adequate for use in

prediction of performance, reliance will be

placed on empirical knowledge (from expert

opinion and existing standards). The first document is expected to have five parts. Part 1

will provide guidance to designers and planners;

Part 2 will be for material and product

manufacturers; Part 3 will be directed to

maintenance planners and building owners, Part

4 will be a glossary of terms, and Part 5 will

present recommended formats for preparation

of service life data.

UK (1995) and Sweden (1996). To facilitate

interaction among some complementary

international committees, meetings of the WG

are coordinated with those of CIB W80/RILEM

140-PSL, Prediction of Service Life of Building

Materials and Components, CIB W94, Design

for Durability, and, in every third year, with the

International Conference on Durability of

Building Materials and Components (DBMC).

A workshop on standards for service life prediction, part of the DBMC, was held in

Stockholm in May 1996. Developed a WG9

report on Design Life of Buildings.

Recent Results

Created a Working Group on Design Life of

Buildings; held meetings in Japan (1993),

Norway (1994), the Netherlands (1995), the

46
BUILDING MATERIALS

DIVISION

CONCRETE

r

Computer-Integrated Knowledge

Systems for High-Performance

Construction Materials and Systems

Principal Investigator

S. Shyam-Sunder

Building Materials Division

(301) 975-6713

Sponsor

National Institute of Standards and Technology

Objective

To develop and demonstrate computerintegrated knowledge systems (CIKS) for highperformance construction materials and systems

(HPCMS).

Problem

The President's National Science and

Technology Council has developed, with strong

endorsement by the industries of construction, a set of National Construction Goals that focus

on better constructed facilities and health and

safety of the construction workforce. The Goals

include a call for significant reduction in

delivery time; reduction in operation,

maintenance, and energy costs; increase in

productivity and comfort; reduction in

occupant related illnesses and injuries;

reduction in waste and pollution; increase in

durability and flexibility; and reduction in

construction work illnesses and injuries. The

highly fragmented nature of the industries of

construction makes it difficult, if not close to

impossible, for all stakeholders - owners,

architects, designers, specifiers, construction

planners, site managers, facility managers,

material suppliers, equipment suppliers, the

labor force, trade/professional organizations,

standards development organizations,

public/private technology transfer centers,

universities and research institutes, and

government/private laboratories -- to access and

use the data, information, and knowledge

necessary for widespread deployment of

HPCMS. Such deployment will contribute to

the realization of the National Construction

Goals and the specific economic and

conrunercial benefits that derive from them. The

major potential benefits of CIKS to industry.

result from the accelerated and widespread

deployment of HPCMS, and include: (a)

reduction in project delivery time; (b) increased

durability or service life; (c) reduced

maintenance and repair, and/or reduced life cycle costs; (d) reductions in cost increases/ overruns and lost time from change orders,

rework, and re-engineering; and (e) increased

access to education and training that will raise

the overall skill level of the construction

workforce and help create the market pull.

Approach

During FY 1996, BFRL will, establish a meta

model for the CIKS, including identification of user needs, available information technologies,

and potential industry-university-government

partners in building the testbed. This model is expected to be based on an open, platformindependent, architecture that uses existing

information technologies, including: intelligent

agents; object-oriented systems; hypermedia

systems; 3-D visualization; database systems;

expert systems; neural networks and learning

systems; high-speed audio, video, and imaging

systems; heterogeneous, distributed systems and

remote data access; high-speed (gigabit)

networks; standard protocols for knowledge

acquisition and representation; and data

standards for integrating system interfaces and

promoting interoperability.

The meta model for the system will seek to

integrate well-developed BFRL computer

applications through the adoption of open data

standards. Collaboration and synergies will be

sought with other ongoing programs within

NIST, industry, academia, and other Federal

agencies. CIKS is expected to provide

cataloging, indexing, searching, retrieval,

routing, browsing, modeling and simulation,

presentation systems, electronic commerce,

collaborative authoring, help/training, distance

learning, and security and integrity. CIKS will

provide the construction industry with 1. universal electronic access through a singlepoint to distributed data, information, and

knowledge on HPCMS; 2. an authoritative

system to design, monitor, and manage the life- cycle performance of constructed facilities; and

3. an open testbed at BFRL to build and

evaluate system architectures, data standards.

49
Computer-Integrated Kriowledge

Systems for High-Performance

Construction Materials and

Systems: High-Performance

Concrete

Principal Investigator

James R. Clifton

Building Materials Division

301-975-6707

Sponsor

National Institute of Standards and Technology

Objective

To develop and demonstrate computerintegrated knowledge-based system (CIKS) for

high-performance concrete for helping the

construction industry improve the speed and

quality of its decisions on High-Performance

Construction Materials and Systems (HPCMS).

Problem

A major need for exploiting the benefits of

HPCMS is providing reliable information about

these materials (composition, properties,

performance, and economics) quickly to the

design and construction community. Owners,

designers, material suppliers, and contractors

benefit from access to information about

HPCMS. Organizing the information in

computer-integrated knowledge systems can

accomplish this. A computer integrated

knowledge systems for HPCMS would consist

of databases, mathematical models, audio/visual

information, standard practices and test methods, and expert reasoning, to help decision

makers in using the most reliable and advanced

knowledge for selecting and using HPCMS.

Although research on HPCMS is still in an early

stage, it is at this stage that potential users most

urgently seek knowledge on its properties and

performance. This project will develop and

demonstrate a computer integrated knowledge

system for high-performance concrete (HPC) as a contribution to a system for all HPCMS.

Approach

During FY 1996, BFRL will perform the

following tasks;

enabling information technologies, and

prototype applications.

Recent Results

New project

50
1. Define an architecture and components of

the system;

2. Develop an information model addressing

the needs of different users;

3. Develop methods for acquisition,

representation and exchange of knowledge to

be incorporated into the system;

4. Develop and demonstrate an operational

system for HPC;

5. Develop database formats for cement data

Also, in this multi year project, provision for

maintaining the system will be addressed. The

information model will indicate knowledge that

should be included, how it will be obtained,

represented, exchanged, and used or

interpreted. Identification of needed

information will be carried out in concert with

the construction industry and its customers

through workshops held with potential users. Potential sources of knowledge include HPCMS

projects being performed within BFRL, other

agencies such as the Federal Highway

Administration and the Corps of Engineers,

NSF-sponsored research, projects sponsored by

trade associations, industrial studies, and

foreign studies. A group of experts from

industry will be invited to collaborate in the

development of CIKS that meet their

foreseeable needs.

The first CIKS to be developed will address

High-Performance Concrete (HPC) and it will serve as a model for systems dealing with other

HPCMS. The system, HYPERCON, will

consist of expert systems and guidelines dealing

with material design, selection of materials,

processing and quality-assurance of HPC,

mathematical models developed in the Building

Materials Division for predicting the

performance of HPCs; database formats and

demonstration databases; and results of

experimental studies being carried out in the

BFRL research on HPCMS. Based on the

experience gained last year in development of an Internet Home Page on HPCMS (describes

the Building Materials Division's research and

published reports electronically), reports can be

downloaded in their entirety. The Home Page

provides a hypertext link to a File Transfer

Protocol (FTP) site for downloading

mathematical models. Using this data, an

expert system will be developed giving

recommendations on constituents and material

properties of HPC for meeting specified

performance requirements. Information by

other BFRL HPC projects on models for

predicting the transport properties of concrete

will be placed in databases and along with test methods, linked with the expert system. Also,

BFRL will develop databases covering

constituents of HPC, including a database on

cement data compiled by BFRL's Cement and

Concrete Reference Laboratory. Its database

format for concrete chemical admixtures and

cement will be completed.

Recent Results

Kaetzel, L., and Clifton, J., "Knowledge

Based/Expert Systems for the Construction

Industry," Materials and Structures, Vol. 28, No.

177, pp. 160-174, 1995.

Struble, L, and Kaetzel, L., "Highway Concrete

(HWYCON) Expert System in the Classroom,"

ACBM Teaching Materials Science Engineering and

Field Aspects of Concrete, July 1995.

51
Microstructure-Property

Relationships in Random Porous

Materials

Principal Investigator

Edward J. Garboczi

Building Materials Division

301-975- 6708

Sponsor

National Institute of Standards and Technology

Objective

To develop more accurate relationships between

microstructure and properties, using computer

models and experiments, and to make these

relationships available in mathematical form to

the cement-based materials community.

Problem

The degradation of the concrete infrastructure,

worth about six trillion dollars, is a national

problem. The basic physical and chemical

mechanisms of degradation processes in

concrete need to be understood to make

scientifically sound and non-empirical service

life predictions. The rates of degradation

processes that affect cement-based materials are controlled by microstructure-related properties

like diffusivity, permeability, and elastic moduli.

Fundamental computer-based models are necessary to quantitatively relate such

properties to the complex microstructure of

cement-based materials. Such quantitative

relationships will assist in predicting the service

life of new and existing concrete.

Approach

During FY 1996, BFRL will develop simulation

models to predict the service life of physical

property of microstructures. Digital -imagebased approach, along with Monte Carlo

techniques, will be used to simulate the

formation of cement-based and ceramic

materials at the fundamental level. Using finite

element and finite difference techniques,

coupled with fast conjugate gradient solvers,

software will be developed to simulate and

compute physical processes and parameters.

These new microstructure and property

simulation algorithms then feed into the other

modeling projects and are focused on the

solution of specific problems. Experimental

measurements are made as necessary, either at BFRL or in collaboration with other institutions

like Northwestern University and Imperial

College, U.IC, to validate the model results.

Recent Results

Schlangen, Erik and Garboczi, Edward J., "New

Method for Simulating Fracture Using a Random Geometry Lattice," International Journal

of Engineering Science, (In press).

Newbauer, C. M., Garboczi, E. J., and Jennings,

H. M., "A Three-phase Model of the Elastic and

Shrinkage Properties of Mortar," journal of

Advanced Cement-Based Materials, Vol.4, pp. 6-

20, 1996.

Douglas, J.F., Thorpe, M.F., and Garboczi,

Edward J., "Geometrical Percolation Threshold

of Overlapping Ellipsoids," Physical Review, E

52, 819-828, 1995.

52
Processing of High-Performance

Concrete

Principal Investigator

Chiara F. Ferraris

Building Materials Division

301-975-6711

Sponsor

National Institute of Standards and Technology

Objective

To develop methods for measuring and

predicting the effects of formulation, curing,

and processing in the performance of highperformance concretes.

Problem

After many years of slow advances in concrete

technology, a worldwide awareness has arisen

that the performance of concrete in areas such

as ease of placement, strength development, and

durability can be significantly improved. This

increased awareness is evident from CEB's

(Commission Euro-International de Beton)

Program and the high-performance concrete

research activities in Japan, Norway, and

Canada. In the United States, programs such as the concrete and structure's program of the

Strategic Highway Research Program (SHRP)

and the establishment of the NSF Center for

Advanced Cement-Based Materials (ACBM)

responded to the need for improved concretes

and the recognition of the possibility of the

development of high-performance concrete

(HPC). The Civil Engineering Research

Foundation (CERF) and the American Concrete

Institute (ACI) have been leading the U.S.

efforts in developing a comprehensive program

on HPC and has prepared a proposed program

that deals with high-performance construction

materials, High-Performance Construction Materials

and Systems: An Essential Program for America and

Its Infrastructure, CERF Technical Report 93-

5011, April 1993. HPC technology is sufficiently different from conventional concrete

technology in that existing test methods and

processing practices (e.g., mixing, consolidating

and curing) may not be applicable to HPC.

Approach

During FY 1996, BFRLwill develop test methods and simulation models for predicting

the rheological behavior and curing of highperformance concrete. Field problems in the

processing of HPC also will be identified. Work

will center on: 1. predicting the rheological

properties of HPC; 2. Evaluating the effect of

curing practices on the performance of HPC;

and 3. Studying the behavior of HPC on alkalisilica reaction (ASR).

To learn if high-strength concrete has a

sufficiently high tensile strength to resist the

expansive stresses from destructively expansive

ASR, BFRL developed a novel apparatus for

measuring expansive forces in mortar bars

caused by ASR In this test, specimens are subjected to severe testing conditions to

accelerate ASR and any expansive forces

resulting measured using a load cell. The results

show there is a need for testing the ASR of

siliceous aggregates for use in HPC.

Studies on the rheological properties, will aim at

developing a method for predicting the

rheological properties of HPC. A method(s)

will be selected and used for measuring the

important rheological properties of cement

pastes and mortars, of a range of compositions

and water-to-cement ratios. BFRL will

continue to develop hydrodynamic models for

predicting the rheological properties of

concentrated suspensions to include cement

paste. Based on the experimental and

modeling efforts, correlations between the

rheological properties of cement pastes and

mortars and HPC will be sought. If reliable

correlations are obtained, this will facilitate the

development of a method for predicting the

rheological properties of HPC tests performed

on cement pastes or mortars.

BFRL will use its new method for studying the

infiuence of curing (temperature and humidity) on hydration of cement paste to determine the

effects of moisture, temperature conditions,

and time on the performance of HPC. An

essential component of this study will be an

investigation of moisture movement in

hardening FIPC. The results of the study on

curing and the state-of-the-art report prepared

53
by BFRL's Structures Division will provide an

essential input to the development of the

Integrated Knowledge System for HPCMS

through an expert system for the curing of

HPC.

Recent Results

Ferraris, C, State-of-the-art of RJieological Testing

Methods, Including die Outline of a Program to Correlate Cement Paste Rheology to Mortar

Rkeology, NISTIR 5869, National Institute of

Standards and Technology, July 1996.

Ferraris, C, Alkali-Silica Reaction and High

Performance Concrete - Progress Report, NISTIR

5742, National Institute of Standards and

Technology, August 1995.

Three-Dimensional

Microstructural/ICinetic Model of

Cement Hydration

Principal Investigator

Dale P. Bentz

Building Materials Division

301-975-5864

Sponsor

National Institute of Standards and Technology

Objective

To develop and validate a comprehensive model

for cement hydration and microstructure

development in three dimensions.

Problem

A lack of a basic understanding hinders

predicting the properties and performance of

cement-based materials of microstructural

development and hydration kinetics. Progress

in this area has been slow due to the complexity

of the starting materials, water and a multi-size,

multi-phase cement powder, and the number

and the complexity of the reactions that occur during hydration.

Approach

During FY 1996, BFRL will continue

development of 1 ) an integrated computer

model for predicting the course of development

of microstructure in hardening cement pastes

and 2) experimental techniques to be used in

model validation. Computer modeling

techniques for reconstructing a threedimensional representation of multi-phase

multi-size cement particles in water and the

cellular automata-based hydration model have

been preliminarily validated against

experimental data for hydration rates, heat

release, and chemical shrinkage. Using the

parabolic dispersion model of Knudsen, a single

relationship has been used to relate model

cycles to real time for Cements 1 15 and 116

issued by CCRL, at three different w/c ratios

investigated experimentally. The model shows

further promise in its ability to predict the

longer (7-day and 28-day) term compressive

strength of ASTM CI 09 mortar cubes from 3-

day values. All studies to date have been

54
performed at room temperature. Two other

temperatures (15°C and 35 °C) will be

irwestigated ar\d maturity-type concepts applied

to relate results at different temperatures. The

hydration model will be modified to create

empty pore space as chemical shrinkage occurs during hydration, so hydration under sealed

conditions can be modeled and compared with

experiments, to provide useful information for

the ongoing research on the curing of concrete.

Ultimately, the model and its real-time

simulation capabilities will be part of the

group's contribution to the Integrated Knowledge-Based System for HPCMS and will be

distributed electronically to industry and

academia through the Inorganic Group and

HPCMS world-wide-web servers and other means. The model is expected to be used in

studying the degree of grinding, w/c ratio, and

usage of admixtures on the resultant

microstructure and properties of cement-based

materials.

Recent Results

Bentz, D.,A Three-Dimensional Cement Hydration

and Microstructi4re Program. I. Hydration Rate,

Heat ofHydration, and Chemical Shrinkage,

NISTIR5756, National Institute of Standards

and Technology, November 1995.

Development of Microstructure and

Permeability in Mortar and

Concrete

Principal Investigator

Edward J. Garboczi

Building Materials Division

301-975-6708

Sponsor

National Science Foundation

Science and Technology Center for Advanced

Cement-Based Materials

Objective

To use microstructural development and

interfacial zone percolation models, with

transport property experiments, to predict the

transport properties of cement paste and

concrete.

Problem

The transport properties of cement-based

materials play an important role in their

durability. Understanding cement paste is fundamental, as it is the matrix material in

concrete. However, the connectivity and

microstructure of interfacial zones in concrete

make the prediction of concrete properties from

cement paste properties a non-trivial task.

Using impedance spectroscopy, it is possible to

carefully study the dependence of the electrical

conductivity of cement paste on its microstructure, and validate BFRL's digitalimage-based model. Applying these results to

interfacial zone percolation models and

transport models, originally developed for

sedimentary rocks, the major transport

properties of concrete can be predicted.

Approach

During FY 1996, BFRL will apply the results of

theoretical predictions for concrete transport

properties using random walk conductivity

simulations and effective medium theories.

Experiments using impedance spectroscopy on

mortar samples are being done at Northwestern

University, and interpretations performed using

BFRL's models. Theoretical work involving

finite element codes will be performed at BFRL

to predict the elastic modi of mortar and

55
concrete, and exannine the piezoelectric

properties of cement paste and study their

effect on transport properties.

Recent Results

E. J. Garboczi, L. M. Schwartz, and D.P. Bentz,

"Interpretation of the Impedance Spectroscopy

of Cement Paste via Computer Modeling III: Microstructural Analysis of Frozen Cement

Paste," Journal of Materials Science, Vol.30, pp

5078-5086. 1995.

Garboczi, E. J., Bentz, D. P., and Schwartz, L. M., "Modeling the Influence of the Interfacial

Zone on the D.C. Electrical Conductivity of

Mortar," Journal ofAdvanced Cement-Based

Materials, p^. 169-181, 1995.

Characterization of Clinker,

Cement, and Flaws in Cement Paste

and Concrete

Principal Investigator

Paul E. Stutzman

Building Materials Division

301-975-6715

Sponsor

National Institute of Standards and Technology

Objective

To develop and demonstrate techniques for

characterization of clinker and cement, and

microstructures and flaws in high-performance

concretes.

Problem

Understanding material properties of cement,

cement paste and concrete, each a complex

multi-phase material, depends upon the ability

to quantitatively characterize their

compositions and microstructures. For example,

the standard method for estimating cement

composition in ASTM C-150, the Bogue

calculation, has long been recognized as inaccurate yet little has been done to correct

this deficiency. X-ray powder diffraction

(XRD) analysis has long been used for

identification of crystalline materials, yet only

about one percent of users apply XRD for the

quantitative analysis of mixtures. This is due in

part to sample processing and data collection

difficulties but, primarily is due to difficulty in

measurement of individual phase diffraction

pattern intensities and in matching reference

phases to the unknowns.

Approach

Whole-pattern fitting using DATAPLOT has

been successfully applied to test mixtures in an ASTM round robin where pattern fitting data

has shown greater precision than peak area measurements. Pattern weights derived from

least-squares fitting of reference patterns to the

mixture pattern can be related to mass fractions

of each component in the mixture. This

procedure is currently being tested using the

NIST Reference Clinkers following a proposed

ASTM Standard Test Method currently under

56
development by their X-ray Powder Diffraction

Task Group. An XRD analysis guide was

prepared from this work and compositional

analyses of CCRL cements 115 and 116 were

obtained from this method.

During FY 1996, BFRL will explore quantitative

analytical methods for determining material

microstructures (including flaws). Application

of backscattered electron imaging in the

scanning electron microscope (SEM) has

allowed researchers to investigate clinker,

cement, hardened cement paste, and concrete

microstructures with resolutions approaching

0.1 micrometers. X-ray imaging and image

analysis facilitates identification and location of

phases such as monosulfate, ettringite, and

gypsum besides calcium hydroxide and calcium

silicate hydrate. Combined SEM/video analysis

will facilitate quantitative descriptions of

microstructure length scales and include

measures of phase composition and

distribution, porosity, and cracking.

BFRL will develop guides for microstructural

characterization of cement clinker and hardened

concretes. These guides will support the

proposed ASTM standard test method on

microscopical analysis of cement clinker, under

development by the microscopy task group, and

ASTM C 856, Standard Practicefor Petrographic

Examination of Hardened Concrete.

Recent Results

Stutzman, P.E., Guidefor X-ray Powder

Diffraction Analysis of Portland Clinker and

Cement, NISTIR5755, National Institute of

Standards and Technology, 1996.

Stutzman, P.E., and Centeno, L., Compositional

Analysis of Beneficiated Fly Ashes, NISTIR 5598,

National Institute of Standards and

Technology, May 1995.

Stutzman, P.E., Quantitative X-ray Powder

Diffraction Methods for Clinker and Cement,

NISTIR 5403, National Institute of Standards

and Technology, May 1994.

Transport Properties of HighPerformance Concrete

Principal Investigator

Nicos S. Martys

Building Materials Division

301-975-5915

Sponsor

National Institute of Standards and Technology

Objective

To provide the technical basis for predicting the

transport properties affecting the service life of

high-performance concrete (HPC).

Problem

Before reliable service life predictions can be

made for HPC structures, a fundamental

understanding of the mechanisms controlling

degradation of HPC is needed. The transport

properties of HPC control many degradation

processes. Although diffusion in HPC has

received some attention, there does not exist a comprehensive body of work that encompasses

all the important material properties (e.g.,

permeability, diffusion, and capillarity) that

control the invasion of HPC by aqueous media.

Experimental methods and standard procedures

are needed to form a basis for reliable

characterization of transport properties.

Approach

During FY 1996, BFRL will study the ingress of

liquids into FIPC by computer simulation and

experiment. Microstructural models, based on

images of authentic microstructures, will be

used in simulation models to relate transport

properties at a microscopic scale (or pore size

scale) to the behavior of the macro structure

(e.g., mortar and concrete). Experiments to

validate the models will be carried out. Also,

BFRL will assess the adequacy of existing test methods for measuring the transport properties

of HPC. If necessary, new test methods will be

developed and submitted to ASTM Committee

C9 on Concrete and Concrete Aggregates for

consideration as standard test methods.

Work will feature modeling of transport in

partially saturated concrete by modifying BFRL

57
simulation models for flow in saturated porous

solids. Usually concrete is treated as fully

saturated or completely unsaturated. The

transport properties, and their simulation

capabilities will be incorporated into BFRL's

Integrated Knowledge System for HPC. It is expected that the results will be distributed

electronically, through BFRL's home pages, and

FTP Internet Site.

Recent Results

Martys, N., and Ferraris, C, "Water Sorption in

Mortars and Concrete," Cement and Concrete

Research (submitted for publication).

Martys, N., "Simulation of Multi-Component

Fluids in Complex Three-Dimensional

Geometries by the Lattice Boltzman Method."

Physical Review E, Vol. 53, pp. 743-750, 1996.

Martys, N., Survey of Concrete Transport Properties

and Tlieir Measurement, NISTIR5592, National

Institute of Standards and Technology,

February 1995.

Matrix Microcracking in Polymer

Composites Under Environmental

and Mechanical Stresses

Principal Investigator

Joannie W. Chin

Building Materials Division

301-975-6815

Sponsor

National Institute of Standards and Technology

Objective

The objective of this project is to study

chemical and mechanical changes in polymer

matrix composites following exposure to UV,

moisture, and mechanical loading for

identifying factors contributing to matrix resin

microcracking under environmental and

mechanical stresses.

Problem

The polymer matrix is a fiber-reinforced

composite binds and orients reinforcing fibers

to carry the intended loads, protects them from

handling and environment, and provides the

interlaminar shear strength of the composite.

However, the matrix is often considered the

weak link in a fiber-reinforced composite

system, since it may crack and craze during

environmental exposure and stress application.

Polymer composites in outdoor applications are susceptible to photo-initiated oxidation leading

to surface degradation and/or crosslinking.

Microcracks which develop in a UV-irradiated

surface provide sites which could potentially

initiate composite delamination, and provide

pathways for rapid ingress of moisture and

chemical agents. Matrix cracking also has been

observed to occur in the early stages of fatigue

cycling and is known to be accelerated by

moisture. The propensity of a polymer to

undergo microcracking is related to, among

other factors, its toughness and ductility.

Toughness, is affected by the moisture content

and crosslink density of the matrix resin. Since

moisture is ubiquitous, and the breakdown

and/or build-up of crosslinks can be

photolytically initiated, moisture and UV

directly impact composite durability. Presently,

there have been no satisfactory studies

58
conducted on the effect of UV exposure on

composite materials, and none which attempt

to relate changes in chemistry and material

properties to durability and service life. The

combined effect of moisture, UV, and loading is not well-documented.

Approach

During FY 1996, BFRL will evaluate the factors

which influence the chemical and mechanical

properties of the polymer matrix resin and

characterize them apart from the fiber

reinforcement. Neat polymer films and model

composites, will be exposed, under static and

cyclic loads, to UV radiation and to UV

radiation combined with varying levels of

relative humidity. Chemical changes which

take place in the unreinforced films will be

characterized with Fourier transform infrared

spectroscopy (FTIR), x-ray photoelectron

spectroscopy (XPS) and differential scanning

calorimetry (DSC). Changes in viscoelastic

response, fracture toughness and residual

stiffness/strength will be evaluated with

dynamic mechanical thermal analysis (DMTA),

static testing and fracture mechanics test methods. Scanning electron microscopy (SEM)

and image analysis will be used to quantify

microcracking in the polymer surface. Atomic

force microscopy will be used to track the

increase in crack density with time.

Results of all tests will be compared with

controls which have not been environmentally

exposed or loaded. Because crack formation and

propagation will be different in a fiberreinforced polymer composite versus the neat

polymer, information on crack density as a function of environmental exposure and

mechanical stress also will be obtained on

model composite systems. When correlations

between exposure/loading conditions,

microcracking and residual properties are obtained for neat and fiber-reinforced polymer

systems, the final stage of this work will involve

collaboration with organizations possessing the

capability to develop models incorporating the

above-mentioned elements.

Recent Results

New project

Service Life Prediction of

Polymer/Fiber Composites in Civil

Engineering Applications

Principal Investigator

Tinh Nguyen

Building Materials Division

301-975-6718

Sponsor

National Institute of Standards and Technology

Objective

To develop and validate models for estimating

shear strength of polymer/fiber composites and

to develop an automated method for

quantifying the effects of environmental

conditions on the durability of polymer/fiber

composites.

Problem

One of the prime concerns on the applications

of polyiiier/fiber composites (PFC) in civil

engineering is the effects of exposure environments on the durability of these materials and

their components over the 50 to 75 year life spans. A particular failure mode is interfacial

shear. The effect of moisture and temperatures

on interfacial shear strength of composites in

traditional applications have been extensively

studied. However, almost no data exists on the

effects of construction environmental

conditions, e.g., concrete and salt water

environments, and their interactions with

temperatures on the interfacial failure of PFC.

Approach

During FT 1996, BITIL will develop models

that predict interfacial failures of PFC under

civil engineering environments. This research

centers around three tasks:

1. Develop effective test method(s) to

characterize interfacial failure,

2. Develop mathematical and conceptual

models to predict interfacial failure, and

3. Conduct experiments to elucidate failure

mechanisms and validate predictive models.

Parameters include environmental water, salt

water, and simulated concrete solutions;

temperature at 22 °C and 60 °C; glass and

59
carbon fibers; fiber surface treatment - untreated and silane treated, and epoxy and

vinyl ester resin matrices. Besides shear

strength, the effects of these parameters on the

thickness of the water layer at the

matrix/substrate interface also will be measured.

Since the water layer at the fiber/matrix

interface is considered to be responsible for the

loss of shear strengths of PFC, data on the

water thickness layer at the molecular level may

provide information for predicting early failure

of PFC in these environments.

Recent Results

Nguyen, T., Byrd, E., Alsheh, D., McDonough,

W., and Seller, J., "Interfacial Water and

Adhesion Loss of Organic Coatings on Siliceous

Substrates," Materials Research Society

Symposium Proceedings, Materials Research

Society, Vol.385, p. 57, 1995.

Static and Fatigue Resistance of

Polymer-matrix Composites

Immersed in Simulated Sea Water

Principal Investigator

Tinh Nguyen

Building Materials Division

301-975-6718

Sponsor

National Institute of Standards and Technology

Advanced Technology Program (ATP)

Objective

To assess the effects of various material,

processing, and environmental factors on the

service life of polymer-matrix composites

immersed in simulated sea water and to develop

mathematical models for predicting the service

life of polymer-matrix composites subjected to

static/fatigue loading while immersed in

simulated sea water.

Problem

Polymer-matrix composites offer considerable

potential for offshore applications because of

their low mass, high strength, fatigue and

corrosion resistance, and tailorability of

mechanical properties. Realizing these

potentials, NIST's Advanced Technology

Program (ATP) has funded several projects to

develop technologies for manufacturing

polymer-matrix composites for offshore drilling

and oil production. To increase the acceptance

of composites in offshore applications,

durability issues such as the effects of fatigue,

creep, and impact on composites immersed in

simulated sea water must be addressed. Fatigue

damage in composites assumes a variety of

forms, including matrix cracking, delamination,

fiber/matrix debonding, and fiber fracture.

Fatigue durability of composites in a marine • environment is of particular concern because

little information exists on the combined effects

of various factors such as sea water uptake,

ionic diffusion, temperature, stress magnitude

and ratio, loading frequency, and loading type.

Approach

During FY 1996, BFRL will characterize and

analyze the progression and mechanisms of

60
damage incurred by continuous members of

fiber-reinforced polymeric composites subjected

to static and dynamic fatigue loadings while

immersed in simulated sea water. This

information will form the basis for developing

models to predict the service life of polymeric

composites under a load in simulated sea water.

Fiber-reinforced polymer-matrix composite

specimens will be subjected to tensile loading

while immersed in simulated sea water at

different temperatures. Specimen geometry and

dimensions will be similar to those described in

ASTM D3039-76, Test Methodfor Tensile

Properties of Fiber-Resin Composites . Tensile loads

will include both static and dynamic loads at 50

percent and 80 percent of ultimate strengths.

Laminated and textile forms of both carbon and

glass fiber-reinforced composites will be studied;

both epoxy and polyester will be employed as the resin matrix. Specimens will be exposed

and tested at 4 °C, 25 °C, and 50 °C at a frequency of 10 Hz. Multiple specimens will be

tested at each experimental condition. For

baseline data and to decouple the loading and

environmental effects, specimens will also be

tested under monotonic loading conditions in

air and the stiffness, strength, and damage

characteristics determined. Damage will be

determined at regular intervals through a combination of edge replication, microscopy

(SEM, and microprobe xray), and measurement

of residual mechanical properties. Mass

transport properties of salt and water will be

measured using radioactive tracers. Based on

experimental evidence, time-dependent (or load

cycle-dependent) damage will be characterized

by a parameter, which captures the essence of

progressive damage and mechanical property

degradation. The damage parameter, which

may be a scalar or tensorial quantity, will be

formulated as for damage patterns generated

during the fatigue process. A damage evolution

or progression law vnW be derived based on the

dissipative energy principle. The service life or

total number of cycles to failure will then be

determined by integration of the damage

evolution law to reach the critical value of the

damage parameter that renders the structure

useless or unserviceable.

BFRL will construct a life prediction model

using a continuum damage mechanics approach

coupled with a finite element technique. The

theory of microcrack growth will first be

developed based on attack of simulated sea water at the crack tip. Evolution of damage will

be formulated based on the microcrack growth

theory. The constitutive law incorporating the

instantaneous damage level will be formulated

taking into account the influence of the

microcrack interactions on the stiffness matrix.

Verification of the validity will be made against

the experimental observations carried out

previously.

Ultimately, a 2D, or 3D, finite-element model

will be constructed to predict the service life of an off-shore substructure subjected to marine

conditions. The model will be capable of

handling the complex geometry of the structure.

Input to the model will be loading conditions

simulating the in-service environment, the

initial (as received) material properties, and the

validated damage evolution law. The solution

scheme will be carried out in incremental time

or loading steps, in analogy to an iterative

scheme in nonlinear elastic/plastic analysis. At

each loading step, stress, strain fields and

stiffness matrix and damage parameters will be

solved until the damage parameter reaches a predetermined critical value. In this way, the

critical regions near the stress concentrators

having the highest stresses can be monitored

and ultimately the service life of the off-shore

structure under various static or fatigue

conditions computed.

Recent Results

New project

61
Spectral Ultra Violet-B Radiation

Database

Principal Investigator

Lawrence Kaetzel

Building Materials Division

301-975-5912

Sponsor

National Institute of Standards and Technology

Objective

To develop a computerized database system of

solar ultra-violet B radiation data for

dissemination as a 1997 NIST Standard

Reference Data Program product.

Problem

Spectral UV-B radiation (solar) data is important to a wide range of scientific

disciplines including materials (e.g.,

degradation of composites, plastics and coatings

and color changes in coatings, and textiles).

The data in the database will be invaluable

input into models for predicting the service life of building materials and in assessing the

relative severity of different exposure

environments throughout the United States.

Currently, the Smithsonian Institution, several

universities, and NIST's Physics Laboratory are

collecting UV-B spectral irradiance data at several locations throughout the United States.

By March 1996, three more NIST sites will be

added to this network making it the largest UVradiation network in the United States.

Approach

During FY 1996, BFRL will perform four tasks:

1. Characterize the data,

2. Evaluate the quality control measures for

data accuracy (e.g., calibration,

transformations )

,

3. Develop database formats that can be used

for data from different sources, and

4. Establish the database to represent outdoor

weathering factors, specifically, solar spectral

UV-B radiation data. A graphical user

interface will be developed during the second

year of this project.

In collaboration with NIST's Physics

Laboratory, solar spectroradiometers will be

calibrated and inter-comparison data sets generated will be used to develop criteria for

establishing guidelines for data set quality.

Databases on the performance of coating

materials will be used to develop the user

interface and to test the use of the

computerized database system for measuring

the environmental effects on materials

performance. The Steel Structures Painting

Council and the BFRL's Coatings Service Life

Consortium activities will be used to obtain

feedback for the user interface and to test prototype systems. It is expected that this

database will provide input for a wide-variety of

models including those for predicting the

appearance service life of coatings exposed

outdoors.

Recent Results

Completed agreement to transfer solar UV-B

data from the Smithsonian Institution

Environmental Research Center. A graphical user interface was selected and designed for

implementing the SRD product.

62
Cementitious Materials Modeling

Laboratory (CMML)

Testing of U.S. Capitol Pavers

Principal Investigator

Chiara F. Ferrarris

Building Materials Division

301-975-6711

Principal Investigator

Edward J. Garboczi

Building Materials Division

301-975-6708

Sponsor

National Science Foundation Center for

Advanced Cement-Based (ACBM)

Northwestern University

Objective

To advance the science of cement-based

materials through the electronic availability of

models and the transfer of modeling knowledge

through workshops and documentation.

Problem

Many cement-based materials models that have

proved themselves in research applications need

to be effectively transferred to the general

materials science of concrete to be of wider use. Also, such models also need to be documented

so others than the developers can use them, and

some researchers, especially graduate students,

need extra training to be able to use the models.

Approach

During FY 1996, BFRL will make available in

hypertext format, its work on cement-based

material modeling. The models will be made

available via anonymous file transfer protocols

(ftp). Users can get the code and request a copy of the documentation. Those who need

further training in the modeling techniques

used in the models can attend the annual

NIST/ACBM Computer Modeling Workshop to

get the required training. Cooperation is maintained with RILEM Committee 123-MME

on Modeling of Cement ACBM faculty, and

other computer modellers around the nation.

Recent Results

Developed an anonymous ftp director and

placed it on the CMML computer

(titan.cbt.nist.gov), making several previously

documented models available to the general

research public.

Sponsor

Office of the Architect of the Capitol

Objective

To determine the reason warping occurred on

concrete pavers, installed in 1992 on the lower

terrace of the Capitol Building.

Problem

The pavers are 1.22 m x 0.61 m x 64 mm and

made of two layers of different concretes. They

were placed in 1992 and about 2 years later

they had warped. The warping caused

unevenness of the walking surface and a

possible trip hazard to visitors to the Capitol.

There is a need to determine the causes of

warping.

Approach

During FY 1996, BFRL will complete a series of

tests to determine the most probable cause of

concrete paver warping. Analyses include

testing whole pavers in conditions simulating

those in the field, measuring the length changes

due to thermal or hydraulic cycles, and alkalisilca reaction (ASR). Other material

characteristics will be measured including

compressive and flexural strength. All tests will

be done on pavers stored in a warehouse and

placed in service.

Recent Results

Ferrarris, C, Stutzman, P., and Clifton, J., Warping of Terrace Pavers at the U.S. Capitol

Building, NISTIR5847, National Institute of

Standards and Technology, May 1996.

63
1

i
BUILDING ENVIRONMENT

DIVISION

COMPUTER

INTEGRATED

CONSTRUCTION

STEP for the Process Plant

Industries

Principal Investigator

Mark E. Palmer

Building Environment Division

301-975-5858

Sponsor

National Institute of Standards and Technology

Objective

To assist the U.S. process plant industries

develop the Product Data Representation and

Exchange (STEP) application protocols

(APs)needed for exchanging and sharing

information during the design and construction,

and maintenance of process plants.

Problem

The U.S. process plant industries seek to

improve their use of computerized systems

through integration of information systems, e.g., automation of the exchange of information

among systems. The many computerized

systems in use can be integrated only at great

cost because of their incompatible proprietary

representations of information; information

exchange today is accomplished largely through

manual methods. Standard, neutral

information representations and exchange

methods are needed that allow system vendors

to be innovative and yet allow system users to

exchange and share information about process

plants automatically. The evolving international

standard ISO 10303 -Product Data

Representation and Exchange, known as STEP,

is providing the base technology. STEP application protocols must be developed that meets the

needs of the process plant industries.

Approach

During FY 1996, BFRL will broaden its expertise in the CAD/CAE/CAx systems used in the

process plant industries and will expand the test case library for validating the draft APs and

evaluating prototype implementations of the

APs. BFRL will work with PlantSTEP, Inc. to

advance Version 1.0 of the Plant Spatial

Configuration AP (AP 227) through the ISO

ballot process. BFRL will work with

PlantSTEP, Inc. to develop the Abstract Test

Suite for AP 227; BFRL will work with pdXi

(Process Data Exchange Institute) to document

the requirements for the Process Engineering

AP, (AP 231) and circulate the requirements

document for review and comment by industry

world wide; and will continue to co-lead the

Process Plant Application Protocol Planning

Project in ISO TC184/SC4.

BFRL will work with industry, standards

development organizations, and international

programs to ensure the delivery of a harmonized suite of STEP APs that meet the

industries' requirements. This will include

participation in or monitoring of at least four

other AP projects:

- AP 22 1 , Functional Data and Schematic

Representation (led by UK)

- AP 2 12, Electrotechnical Plants (led by

Siemens, Germany)

- AP 228, HVAC (led by France)

- AP 230, Building Structural Steel (led by

UK)

and, potentially, the development of extensions

to some AP projects. Additionally, this project

will educate industry about the potential

benefits of STEP and will motivate organizations, e.g., ISA (International Society for

Measurement and Control), and industry to

actively participate in defining requirements

and reviewing draft solutions.

It is expected that this multi-year project will

develop and standardize a product data model

to support: 1. the selection and use of

commodity items; 2. the exchange of process

engineering information; 3. the exchange of

process and piping schematics; 4. the design of

piping systems; 5. the exchange of shape and

physical arrangement information for other

plant systems; and 6. the exchange of piping

system data between engineer and fabricator.

Recent Results

Burkett, W., Craig, D., Kline, S., Palmer, M.,

and Skeels, J., Plant Spatial Configuration

Application Protocol, Version 1.0, NISTIR 96-

5812, National Institute of Standards and

Technology, 1996.

Burkett, W., Kline, S., Palmer, M., and Skeels,

67
J., Group 1 for the STEP Plant Spatial

Configuration Application Protocol, NISTIR 95-

5675, National Institute of Standards and

Technology, 1995.

Palmer, M.E. and Reed, ICA., 3D Piping IGES

Application Protocol Version 1.1, NISTIR 4797,

National Institute of Standards and

Technology, 1994.

Beazley, W. G. And Chapman, J.B.,^

Frameworkfor Information Technology Research in

Process Plant and Related Industries, NIST-GCR94-657, National Institute of Standards and

Technology, 1994.

AMSANT for the Process Plant

Industries

Principal Investigator

Kent A. Reed

Building Environment Division

301-975-5852

Sponsor

National Institute of Standards and Technology

Objective

To establish and use an experimental computing

and communication facility 1) to provide a baseline of industrial practice in process plant

engineering and construction, 2) to support the

companion projects—STEP for the Process

Plant Industries and Process Plant Engineering

and Construction, 3) to serve as an open

testbed for integration activities of industrial

partners, and 4) to serve as a communications

hub for all U.S. participants.

Problem

The process plant industries comprise highly

competitive vendors and users of computerized

systems for the design, construction, and

maintenance of process plants. An open facility

is needed in which these players can test proposals for integrating their computerized

systems without bias or unnecessary disclosure

of proprietary developments.

Approach

During FY 1996, BFRL will work with process

plant industries to determine testing and

demonstration scenarios for the STEP

application protocols being developed. BFRL

researchers will use their laboratory facilities

previously established to conduct tests and to

host demonstrations. Work will rely extensively

on using the Internet E-mail, file, and Web

servers to support the protocol developers.

Recent Results

Evaluated the EXPRESS schema developed for

STEP Application Protocol 227—Plant Spatial

Configuration.

Constructed data probes for use in creating

STEP Exchange files containing test case data.

68
Process Plant Engineering and

Construction: Structural Systems

Principal Investigator

Kent A. Reed

Building Environment Division

301- 975-5852

Sponsor

National Institute of Standards and Technology

Objective

To work with U.S. industry to develop a

technical capability to represent and Exchange

information supporting the design and

construction of structural systems using

internationally accepted protocols.

Problem

The U.S. construction industry seeks to

improve its use of computerized systems

through integration, e.g., automation of the

Exchange and sharing of information among

systems. The evolving international standard

ISO 10303, Product Data Representation and

Exchange (STEP), is providing the base

technology. The U.S. structural engineering

corrununity has recognized the advantages of

STEP and seeks to make STEP Exchange viable

in its computerized design, analysis, and

fabrication systems.

Approach

During FY 1996, BFRL will work in

collaboration with the American Institute of

Steel Construction to critique the European

CIM Steel submission to ISO TC 184/SC 4 and

will develop a U.S. position on the STEP

Structural Steelwork project. During this time,

BFRL will work with Carnegie Mellon

University to establish a technical basis for the

position. Staff will seek input from the

reinforced concrete structures community.

Recent Results

Developed a steelwork design test case, reviewed, critiqued available CIM Steel

documentation, and established with AISC, an AISC Task Group as the U.S. participant in the

STEP Structural Steelwork project.

STEP for the Building Industry

Principal Investigator

William F. Danner

Building Environment Division

301-975-5855

Sponsor

National Institute of Standards and Technology

Objective

To demonstrate the use of the Product Data

Representation and Exchange (STEP)

architecture and methods for the development

of related application protocols (APs) for

building industry sectors (e.g., process plants)

that accommodates information exchange and

sharing; formulate a strategy to develop

coordinated application activity models

(AAMs), industry application scopes, and

application information requirements for

related APs; and describe building industry

requirements for enterprise integration and the

degree to which STEP can be used to address

those requirements.

Problem

Industry sectors such as process plants require

suites of related APs to deal with all the data

about a product over its entire life cycle. A

detailed understanding of the STEP architecture

and methods, the AP data specification process,

and AP implementation are required as a basis

for the development and use of suites of related

APs. Principal among the issues raised

concerning the STEP architecture and methods

is the degree to which STEP supports business

requirements that cross application protocol

boundaries. A strategy is needed that allows

phased and distributed development but that

provides an appropriately integrated result for

commerce and industry. There is considerable

interest in the building industry to use information technology to facilitate enterprise

integration. Most participation in STEP has

been related either directly or indirectly to this

interest. STEP has provided a standard for the

Exchange of product data within specific

application contexts specified in APs. Industry

requires an assessment of the degree to which

STEP APs can be used to accommodate

69
enterprise integration requirements.

Approach

During FY 1996, BFRL will develop APs using

the architecture and methods of STEP. These

examples will be the basis for a detailed

description of how related APs are developed

using the architecture and methods of STEP.

They also will be used to describe how related

APs can be used for product data Exchange and

product data sharing in typical computer system

architectures. BFRL researchers will assess alternative approaches to a phased and

distributed development of APs. The relative

merit with respect to providing for product data

integration within and among sectors of the

building industry will be the principal criterion.

BFRL has provided an electronic forum for

worldwide discussions of building industry concerns about the use of STEP in meeting

industry requirements for enterprise integration.

An analysis of these discussions has provided

ten principal building industry requirements.

The degree to which STEP can accommodate

these requirements will be undertaken with

suggestions for an additional focus in areas of

deficiency.

Recent Results

Contributed development of ISO 103003-13

Architecture and Metliods Reference Manual

including: 1. the design principles of the STEP

architecture; 2. the conceptual framework of the

architecture about its functional components; 3. description of the standard product data

constructs used in the generic model of product

data; and 4. application protocol

implementations.

Object Oriented Implementation of

STEP

Principal Investigator

Kent A. Reed

Building Environment Division

301- 975-5852

Sponsor

National Institute of Standards and Technology

Objective

To work with U.S. industry to ensure proper

deployment of the Product Data Representation

and Exchange (STEP) in emerging software

scenarios.

Problem

The U.S. construction industry seeks to

improve its use of computerized systems

through integration, e.g., automation of the

Exchange and sharing of information among

systems. Some industrial sectors have pursued

the development of ISO 10303 Product Data

Representation and Exchange (STEP), to enable

integration at the information level. Recently,

however, the members of the general building

and construction industry have formed the

Industry Alliance for Interoperability (lAI) to

pursue the development of object class libraries,

known as IPCs, to enable integration at the

application programming interface level. Careful

liaison is required to ensure these approaches

are compatible.

Approach

During FY 1996, BFRL will work with the

industry Alliance for Interoperability ResearchAdvisory Committee to define the relationship

between IPCs and STEP. Researchers will

prepare position papers on STEP technologies

as appropriate to aid lAI and to bring lAI issues

to appropriate STEP committees for resolution.

Recent Results

New project

70
BUILDING ENVIRONMENT

DIVISION

HEAT TRANSFER

Development of 2-Dimensional Heat

and Moisture Transfer

Principal Investigator

Douglas M. Burch

Building Environment Division

301-975-6433

Sponsor

National Institute of Standards and Technology

Objective

To develop a 2-dimensional personal connputer

model that predicts the combined transfer of

heat and moisture in building construction.

Problem

BFRL has developed a "one-dimensional"

personal computer model, called MOIST, that

predicts heat and moisture transfer in building

construction. This model inputs hourly

outdoor weather data, and predicts the moisture

content and temperature of the construction

layers as a function of time of year. The

capability of MOIST to predict the moisture

accumulation within each building material as a function of time allows the user to select the

most appropriate building materials and

construction for a given climate. A limitation of

the MOIST model is it does not address

important building applications (e.g., rising

damp in earth-coupled foundation walls, water

leakage into basements, the effect of framing

members on heat and moisture transfer, etc.).

Needed is a two-dimensional model to permit

building practitioners to investigate the

performance of various 2-dimensional building

constructions as a function of indoor and

outdoor climate and ground water level. By

performing multiple computer runs and varying

the construction, building practitioners can

learn which constructions perform well, which

do not.

Approach

During FY 1996, BFRL will develop a twodimensional personal computer program that runs from a Windows 95 operating system.

Work will involve two tasks:

1. An inpuU'output processor will be developed

that permits the program user to draw the

building construction on the computer

screen using a calibrated cursor. The

program will be equipped with a database of

heat and moisture property data. The user may create a new material in the database

with unique property values. Clicking the

mouse at various locations will establish the

nodal spacing for the finite-difference

solution within the construction. All data

entry will be accomplished in a Windows

environment. When RUN is selected from

the main menu, the program will solve for

the temperature and moisture content at the

specified finite-difference nodes as a function

of time. Moisture distribution within the

construction will be displayed in a colorcoded image with each color representing a

different moisture content.

2. A set of equations will be developed that

perform a heat balance at the finitedifference nodes and calculate the nodal

temperatures at each time step of the

analysis. A separate set of equations will be

developed that perform a moisture balance

at the finite-difference nodes and calculate

the nodal moisture contents at each time

step of the analysis. Special features of the

model include:

the effect of moisture on the thermal

conductivity of materials,

latent heat associated with water

evaporating from one location of the

construction and condensing at another

location,

incident solar radiation onto boundary

segments having an arbitrary orientation

and compass azimuth,

variable indoor relative humidity at one

of the boundary segments calculated from

a moisture balance of the whole building,

moisture transfer by both diffusion and

capillary flow, and

anisotropic, moisture-dependent,

transport properties.

Recent Results

BFRL verified the MOIST algorithms by

comparing them to a series of laboratory

experiments using a calibrated hot box; added

MOIST algorithms to account for ventilated

cavity spaces .

73
Test Procedures for Advanced

Thermal Insulation Products

Principal Investigator

A. Hunter Fanney

Building Environment Division

301-975-5864

Sponsor

National Institute of Standards and Technology

Objective

To evaluate thermal measurement techniques

applicable to advanced insulation systems.

Problem

Advanced insulation products are being

developed and introduced into the U.S. market.

Examples of these products are aerogels, powder

filled panels, and evacuated panels. These

products offer extremely high insulating

capabilities. For example, theoretical

calculations reveal that a R-value approaching

100 may be achieved in a 25.4 mm thick

evacuated panel. Current test procedures for

measuring thermal conductivity are only

applicable to materials that are homogenous,

have planar surfaces, and have, compared with

advanced insulation products, relatively poor

insulating capabilities. Appropriate

measurement techniques and measurement

apparatus are needed to permit accurate

determination of the overall thermal

conductance of advanced insulation systems.

Approach

During FY 1996, BFRL will perform extensive

modifications to its new calorimetric facility to

permit testing of large panels and to make it less

susceptible to external environmental

conditions. Finite element calculations will be

performed to quantify the effect of the test apparatus on the measured thermal resistance of

gas-filled panels. The new calorimeter will be

calibrated using specimens of known thermal

conductivity. Additional CRADA(s) will be

established with manufacturers of advanced

insulation products to assist them in the

experimental and analytical evaluation of their

design concepts. BFRL's efforts in this

measurement technology area will continue to

assist industry in the design and evaluation of

advanced insulation concepts.

Recent Results

Fanney, A. H., "Evaluation of gas-filled

evacuated panel technology" Test Procedure for

Advanced Insulation Panels, BETEC Conference on Superinsulation Technology, November 1995.

Fanney, A.H., "Test Procedures for Advanced

Insulation Panels," Proceedings of the 1994

International CFC ami Ilalon Alternatives

Conference, 1994.

74
Low-Temperature and HighTemperature Thermal Insulation

Reference Materials

Principal Investigator

Robert R. Zarr

Building Environment Division

301-975-6436

Sponsor

National Institute of Standards and Technology

Objective

To establish a low- and a high-temperature

guarded hot-plate laboratory for certifying

thermal insulation Standard Reference

Materials over an extended temperature range.

Problem

During 1995, NIST's Materials Evaluation

Division, Boulder, Colorado decommissioned

several apparatuses used to measure thermal

conductivity. Two apparatuses were used to

develop and establish thermal insulation

Standard Reference Materials (SRMs) at low

and high temperatures. For example, one

apparatus provided SRMs of certified values of

thermal resistance from 100 K to 330 K (SRMs

1450b and 145 1). Recognizing the necessity

for this apparatus, American Society for Testing

and Materials (ASTM) Committee C-16 on

Thermal Insulation requested NIST consider

reestablishing these measurement capabilities

within BFRL.

Approach

During FY 1996, BFRL staff will arrange for

transfer and transportation of the thermal

conductivity apparatus to Gaithersburg. A

suitable laboratory module will be modified at BFRL to accommodate the equipment. With

assistance from the staff in Boulder, the lowand high-temperature guarded hot plates will be

reassembled to their previous configurations.

After set up, initial shake down tests will be

conducted to check the operation of the apparatus.

After completing the shake down tests, the

apparatus will be extensively evaluated to assess

its accuracy. The evaluation will be based on a

series of experiments and theoretical analysis.

Cross-checking with BFRL's one-meter guarded

hot plate will provide a benchmark at room

temperature. If deemed acceptable, the high

temperature guarded hot plate will be included

in a high-temperature interlaboratory (roundrobin) comparison organized by ASTM C-16.

Results of the round robin will provide valuable

data on the performance of the hightemperature guarded hot plate concerning the

apparatus operated by industry. Upon

completion of the evaluation, the apparatus will

be available for development of SRM 1450c.

Recent Results

New project

75
Fibrous-Glass Thermal Insulation

SRM

Principal Investigator

Robert R. Zarr

Building Environment Division

301-975-6436

Sponsor

National Institute of Standards and Technology

Objective

To renew Standard Reference Material 1450c,

fibrous-glass board thermal insulation.

Problem

BFRL provided the first lot of Standard

Reference Material (SRM) 1450, fibrous-glass

board in 1978. Several productions runs

followed. Through SRM sales at NIST, this

supply has been depleted. Since BFRL has

improved its apparatus for absolute

measurement of thermal resistance of thick and

low-density test specimens used as transfer

standards, new certified values need to be

established for the thermal resistance of fibrousglass board, to be designated SRM 1450c.

Approach

During FY 1996, BFRL will determine the

temperature range of interest to the thermal

testing community to develop SRM 1450c.

Questionnaires, private discussions, and open

forums at an ASTM Committee C-16 Meeting

will survey the industry on the desired

requirements for SRM 1450c. A small quantity

of candidate material will be obtained and

evaluated. The evaluation includes: material

uniformity, density and thickness distribution,

shot content and thermal conductivity measure- ments at 297 K using BFRL's one-meter

guarded-hot-plate. To enhance uniformity, all specimens will be taken from the same

production run.

The experimental design for characterizing the

material will be a full factorial of 15 thermal

conductivity measurements at 5 temperatures

and 3 densities. BFRL will consult with NIST's

Statistical Engineering Division for final

comments on the experimental design. The

thermal conductivity of the SRM will be

certified as a polynomial function of

temperature and density having at most a

fourth order temperature term and second order

density term. The final model will be

determined from the best fit of the thermal

conductivity data. Uncertainty bands will be

placed on the fitted polynomial equation.

Recent Results

New project

76
A Photovoltaic Solar Water Heating

System

Principal Investigator

A. Hunter Fanney

Building Environment Division

301-975-5864

Sponsor

National Institute of Standards and Technology

Objective

To develop computer simulations for

photovoltaic solar water heating systems.

Problem

A solar w^ater heating system employing

photovoltaic solar modules has recently been

patented. The photovoltaic solar hot water

system offers significant improvements over

solar thermal hot water systems. For example it does not require a fluid and associated piping to

transport energy produced by the collectors to

the storage tanks and does not require an

inverter to convert the direct current supplied

by the photovoltaic array to alternating current

or a battery system for storage. Presently,

computer simulation tools do not exist for solar

photovoltaic hot water systems. Experimental

data required for computer model validation

exists for one geographical location,

Gaithersburg, Md. The design and system

components need to be optimized further to

reduce the initial system cost.

Approach

During FY 1996, BFRL will award a grant to

the University of Wisconsin to develop

simulation tools to determine the optimum

number and resistance values of the heating

elements for any given geographical location.

The model will provide estimates of the

displaced conventional electrical energy on a

daily, weekly, monthly, and yearly time scales.

Predictions of electrical demand reductions and

the impact on the environment through

widespread use of the solar photovoltaic solar

water heating system will be possible with these

simulation tools.

An extensively instrumented system will be

installed at the Florida Solar Energy Center

(FSEC). This system will be identical to the

system currently being evaluated by BFRL at its

site in Gaithersburg, Md. Under sponsorship of

the U.S. Air Force, two solar photovoltaic solar

water heating systems will be installed at the

Kadena Air Force Base in Okinawa, Japan in

early 1996. The systems will be instrumented

to a level required to access the solar

contribution to the total hot water load. A

fourth system, sponsored by Tennessee Valley

Authority, vAW be installed in the Great Smokey

National Park in 1996. These four systems will

provide the data required to validate the

computer simulation models.

Activity related to reducing the initial cost of a photovoltaic solar water heating system will

concentrate on working with a heating element

manufacturer to develop a multiple resistive

assembly within a single housing and to explore

the possibility of a single-tank photovoltaic

solar water heating system. A design goal of the

single-tank system is to ensure that an adequate

supply of hot water is available during extended

periods of poor weather conditions.

It is expected that the findings from this

research will: 1. produce a complete

understanding of the technology; 2. develop

appropriate computer modeling tools and; 3. encourage commercialization of the

photovoltaic solar water heating technology by

establishing links with the private sector.

Recent Results

Fanney, A. H., and Dougherty, B. P., "A

Photovoltaic Solar Water Heating System,"

1996 International Solar Energy Conference,

ASME, March 31- April 3, 1996.

During 1994-1996, Articles on the Photovoltaic

Solar Water Heating System were published in;

ASHRAE Journal, Business Sl Industry, Consumer

Research, Design News, Discover, Energy &. Housing

Report, PC Today, Popular Science, Science News,

Technology Transfer Business , Tlie Indian Concrete

Journal, Tlie Solar Letter, and New Scientist.

Received a Patent Award, Photovoltaic Solar

Water Heating System by Fanney, H. and

Dougherty, 8 March 1994.

77
i
BUILDING ENVIRONMENT

DIVISION

INDOOR AIR QUALITY
(
Indoor Air Quality Modeling with

Computational Fluid Dynamics

Principal Investigator

Steven J. Emmerich

Building Environment Division

301-975-6459

Sponsor

National Institute of Standards and Technology

Objective

To investigate options for using a large eddy

simulation computational fluid dynamics model

for studying building ventilation and indoor air

quality.

Problem

There are two general types of computer

simulation techniques for studying airflow and

contaminant distribution in buildings - multizone modeling and room airflow modeling.

Multizone modeling takes a macroscopic view

of indoor air quality (lAQ) by evaluating

average pollutant concentrations in the different zones of a building as contaminants are transported through the building and its HVAC

system. Room airflow modeling takes a microscopic view of lAQ by applying a computational fluid dynamics (CFD) program

to examine the detailed flow fields and

pollutant concentration distributions within a room. Each is appropriate for studying different

building ventilation and lAQ problems.

Several years ago, a CFD program called

EXACT was developed by BFRL for studying

room airflows and was applied to the prediction

of ventilation system performance in an open

office space. EXACT employed a k-epsilon

turbulence model then considered the only

practical method for modeling turbulent

airflows. Recently, a CFD program has been

developed at BFRL to simulate the transport of

smoke and hot gases during a fire in an

enclosure. This new CFD model employs

highly efficient solution procedures and a technique, called large eddy simulation (LES),

to eliminate the need for an empirical

turbulence model. This LES-CFD model may

provide an opportunity for BFRL to make a

unique contribution to solving building

ventilation and L\Q problems for the building

industry. There is a need to examine the

appropriateness of this tool for investigating

ventilation and lAQ problems.

Approach

During FY 1996, BFRL will explore using a LES-CFD program to study building ventilation

and L\Q. The first task of this effort will be to

learn unique features of the LES-CFD model

that are advantageous or disadvantageous to

studying building ventilation and L\Q . Also,

attention will be given to identifying additional

features needed to study problems of interest.

The second task will be to learn the current

state of research in the area of CFD modeling of

building ventilation and LAQ through a

literature review, professional contacts, and

technical conferences. A focus of the task will

be learning applications of interest to the

building and L\Q industries. Potential

applications to be explored include modeling of

building material emission and adsorption of

volatile organic compounds, coupling of CFD

and multizone programs, and the thermal

comfort performance of innovative building

ventilation systems (e.g., cold air distribution).

Recent Results

New project

81
Chemistry and Mass Transport

Modeling for Indoor Air Quality

Principal Investigator

George Walton

Building Environment Division

301-975-6421

Sponsor

National Institute of Standards and Technology

Objective

To modify the advanced airflow and

contaminant dispersal model CONTAM series

to include new capabilities in chemistry and

mass transport modeling.

Problem

Multizone airflow and contaminant models

have been developed at BFRL, including

AIRNET and CONTAM86 through

CONTAM93. These models were all unique at the time of their development and have been

useful for the study of airflow and indoor air

quality in multizone building systems.

CONTAM, and other indoor air quality models,

have always been limited in their ability to

model chemistry and mass transport. These

physical mechanisms are taking on increasing

importance in the prediction of indoor

contaminant levels given the identification of

the impact of specific chemical reactions that occur indoors, the increased interest in material

emissions, adsorption and desorption, and the

need to model gaseous air cleaning devices.

Current indoor air quality models have not

implemented the theory that is available to

handle these issues properly. In 1995, BFRL

awarded a contract for the development of an

analysis of existing theory in chemistry and

mass transport and the identification of new

component models to implement in future

versions of CONTAM.

Approach

During FY 1996, BFRL will implement new

component models of chemical reaction and

mass transport for incorporation into

CONTAM. A new version of CONTAM will be

developed which will have state-of-the-art

capabilities to model homogenous and

heterogeneous chemistry, adsorption and

desorption of airborne contaminants from solid

and liquid phase substrates, and the transport

of indoor aerosols.

Recent Results

Axley, J. W., New Mass Transport Elements and

Components for the NIST lAQ Model, NIST-GCR

95-676, National Institute of Standards and

Technology, July 1995.

82
Development of lAQ Model for

Designers

Principal Investigators

Andrew K. Persily

Building Environment Division

301-975-6418

George Walton

Building Environment Division

301-975-6421

Sponsor

National Institute of Standards and Technology

Objective

To develop an indoor air quality design tool.

Problem

Multizone airflow and contaminant models

have been developed at BFRL, including

AIRNET and CONTAM86 through

CONTAM93. TTvese models were unique at the

time of their development and have been useful

for the study of airflow and indoor air quality in

multizone building systems. However, most

indoor air quality models, including CONTAM,

have been used primarily by researchers,

consultants and sophisticated designers. The

design community at large still needs an indoor

air quality analysis program that meets their

needs and is appropriate to their technical level.

Approach

During FY 1996, BFRL will begin a three-year

project working with the National Research

Council of Canada (NRCC) to develop an

indoor air quality modeling tool for design

professionals. Based on an agreement between

NRCC and BFRL, this project is in the first year

of a three-year effort to develop the model

structure and a version of CONTAM that is compatible with this structure. The model will

include three components:

the first two components will be a VOC

emission rate database and a single-zone

room air motion model, both of which are being developed at NRCC, and

the third component of the model is a multizone airflow and pollutant transport

model, that will be a revised and updated

version of CONTAM.

Recent Results

New project

83
Infiltration and Ventilation in Large

Buildings

Principal Investigator

Andrew K, Persily

Building Environment Division

301-975-6418

Sponsor

Department of Energy

Office of Building Technologies

Objective

To analyze energy impacts of large building

infiltration and ventilation system airflows

employing integrated building thermal analysis

and network airflow analysis, and to participate

in industry consensus standards development

activities.

Problem

Previous research and field investigations have

shown that despite current design goals, the

envelopes of modern office buildings often fall short of design expectations about airtightness

performance. In addition, field testing has

shown that ventilation system airflows are often

quite different from their design values, leading

to over- and under-ventilation and increasing

the pressure differences that drive envelope

leakage. The existence of such envelope

leakage, and ventilation system airflows that are not in accordance with design, will increase the

energy loads of a building. Besides the energy

penalties, envelope air leakage can also

negatively impact indoor air quality, envelope

material durability and occupant comfort.

However, the quantitative energy implications

of envelope leakage and ventilation system

airflows are not known, in part due to a lack of

ability of thermal analysis models to properly

account for the complexities of building airflows

in large, multi-zone buildings. Although

sophisticated network airflow analysis programs

are available, such as AIRNET developed at BFRL, thermal analysis models are currently not

able to incorporate the output of such airflow

models. Such an integration of thermal and

airflow analysis is necessary to properly account

for the energy impacts of infiltration and

ventilation system airflows.

Approach

During FY 1996, BFRL will perform two tasks:

1 . BFRL will perform a study of the energy

impacts of infiltration and ventilation

system airflows. Work will build on existing

abilities and expertise in the field of large

building airflow to perform a comprehensive

analysis of the energy impacts of infiltration

and ventilation system airflows and to assess the national impacts of energy conservation

strategies in this area. This analysis will

employ the building energy simulation

program TRNSYS. TRNSYS is modular in

nature, and there is currently a library of

modules available for performing building

energy simulations. These existing TRNSYS

modules will be used with a new TRNSYS

module based on the multi-zone airflow

program AIRNET to provide the needed

simulation capability. The model will be

used to analyze airflow and energy use in

selected prototype buildings. Two subtasks

will be completed in this effort. The first centers on developing a TRNSYS module of

AIRNET to in analyze the energy impacts of

infiltration and ventilation in large,

multizone buildings. The second subtask

will develop an analysis strategy to study

these energy impacts based on the TRNSYS

computer simulation program and begin the

analysis needed to quantify these impacts.

2. BFRL will contribute to development of an

industry consensus standard and guidelines.

To provide the HVAC industry with the

benefits of DOE-supported research results,

BFRL will assume leadership roles on

ASHRAE SSPC 62 "Ventilation for

Acceptable Indoor Air Quality," ASHRAE

129P "Method of Test for Ventilation

Effectiveness" and ASHRAE Guideline 10

"Criteria for Achieving Acceptable Indoor

Environments," and on ASTM

Subcommittee E6.41 Air Leakage and

Ventilation Performance and Indoor Air

Quality.

Recent Results

Emmerich S. J., Persily A. IC, Van Bronkhorst

D.A.,A Workplan to Analyze the Energy Impacts of

Envelope Airtightness in Office Buildings , NISTIR

5758, National Institute of Standards and

Technology, December 1995.

84
Van Bronkhorst D. A., Persily A. IC, Emmerich

S. J., "Energy Impacts of Air Leakage in

U.S. Office Buildings," 16th AIVC Conference,

Air Infiltration and Venilation Centre,

September 1995.

Principal Investigator

Andrew IC Persily

Building Environment Division

Demonstration of Residential

Ventilation Systems

ASTM Provisional Standard P540, Guidefor

Using Indoor Carbon Dioxide Concentrations to Evaluate Indoor Air Quality and Ventilation,

301-975-6418

Sponsor

Synertech Systems Corporation

December 1995.

Objective

To evaluate the performance of residential

ventilation systems based on multizone airflow

and contaminant modeling of houses in a field

monitoring program.

Problem

A variety of approaches to mechanical

ventilation in residential buildings exist, which

control indoor contaminant levels while

maintaining thermal comfort and controlling

energy consumption. The New York State

Energy Research and Development

Administration recently sponsored a project to

identify and analyze the energy and indoor air

quality impacts of ventilation approaches to

residential construction. This project, performed

by the California Institute for Energy Efficiency

and Lawrence Berkeley Laboratory, included

the collection of cost and performance data for

ventilation approaches from past studies and

telephone surveys with HVAC contractors.

These data formed the basis for detailed

analyses of the most promising approaches to

evaluate their ventilation characteristics, energy

usage impacts and life cycle costs in new and

existing buildings. The results of these analyses

have identified the most effective systems in

New York State and California. A Ventilation

Guide discussing the issues associated with

ventilation and the most appropriate system for

New York State homes was developed from the

results of these analyses.

The New York State Energy Research and

Development Administration has moved onto

the second phase of this effort in which the

actual performance of the most promising

ventilation systems will be evaluated in a sample of New York State homes. This second

85
phase is being conducted by Synertech Systems

Corporation with a number of subcontractors,

including BFRL. The performance evaluation of

this second phase will involve installing

ventilation systems in 26 homes and performing

detailed monitoring in eight of them. The

monitoring will include measurements of airflow

rates and selected indoor air quality parameters.

Approach

During FY 1996, BFRL will perform computer

simulations of the homes with detailed

monitoring wdth the multizone airflow and

indoor air quality model CONTAM, developed

by BFRL. The houses will be set-up in

CONTAM, with input values determined by

site measurements. Simulations will be

performed for the monitoring period to

determine the ability to predict the measured

values. Once this ability has been established,

longer term simulations will be performed to

understand the overall performance of the

ventilation systems, their impact of several

important indoor air quality parameters, and

the existence of interactions between the

ventilation systems and other building systems.

The results obtained from these simulations will

be compared with the trends predicted during

the first phase of the effort.

Recent Results

New project

Indoor Air Quality Monitoring in

Green Buildings

Principal Investigators

Andrew IC Persily

Building Environment Division

301-975-6418

W. Stuart Dols

Building Environment Division

301-975-5860

Sponsor

National Institute of Standards and Technology

Objective

To develop systems that monitor the

environmental performance of green buildings

and to implement a monitoring program in

selected green buildings.

Problem

Green buildings are designed to have minimal

impacts on global, local and indoor

environments. A major consideration in their

design is indoor air quality, primarily as to low

indoor contaminant levels but also about

thermal comfort. The energy consumption of

the building to provide a healthy indoor

environment is also an important consideration.

While much effort has gone into discussions of

the technical means to meet these design

objectives, little effort has been devoted to

evaluating the actual performance of these

buildings concerning these goals. To determine

whether green buildings and the associated

technologies are performing as intended, field

monitoring is needed in a variety of contexts. A

key element to such performance evaluation is real-time monitoring of indoor environmental

conditions, mechanical equipment operation

and energy consumption.

Approach

During FY 1996, BFRL will continue the

monitoring effort in several Green Buildings.

This work is similar to that performed by BFRL

last year where several buildings were evaluated

for their appropriateness in the monitoring

program based on the building type, mechanical

system design, location and construction

86
schedule. Measurements will be taken in the

Audubon and Natural Resources Defense

Council in New York. Longer term monitoring

efforts are being pursued in the Montana State

University project and the new AAAS Building

in Washington, DC. In addition, a protocol

will be developed and demonstrated to measure

VOC source strengths in the field.

Measurements will be made in "green" and

"conventional" buildings to evaluate the

protocol and to determine how much success was achieved in the green buildings about

material emission rates.

Recent Results

New project

lAQ Analysis of Residential

Ventilation Systems

Principal Investigator

Andrew IC Persily

Building Environment Division

301- 975-6418

Sponsor

Electric Power Research Institute

Objective

To assess the indoor air quality and ventilation

performance of residential ventilation systems

using multizone airflow and contaminant

modeling.

Problem

A variety of approaches to mechanical

ventilation in residential buildings exist, which

are intended to control indoor contaminant

levels while maintaining thermal comfort and

controlling energy consumption. BFRL recently

completed a project for the U.S. Consumer

Product Safety Commission (CPSC) in which

many single-family residential buildings were

modeled using the multizone airflow and indoor

air quality program CONTAM. Simulations

were performed to predict indoor pollutant

levels due to a variety of sources and to assess the impact on these pollutant levels of a few

indoor air quality control technologies. The

technologies considered were modifications of

conventional forced-air distribution systems and

included enhanced particulate filtration, heat

recovery ventilator installed on the return side

of the system, and an outdoor air intake duct

connected to the system return. The

effectiveness of these controls was a function of

the source characteristics, building factors, and

the outdoor pollutant concentrations.

Sometimes, pollutant concentrations were

reduced by as much as 70 percent. In other

cases, the reductions were lower and even

resulted in increased indoor concentrations.

This effort contributed a significant amount of

insight to issues of residential indoor air quality.

However, many indoor air quality control

approaches, including several promising

approaches to residential ventilation that are currently being used in the field, were not

87
considered in this project.

Approach

During FY 1996, BFRL will employ its multizone airflow and indoor air quality model

CONTAM to assess the impact of a number of

approaches to residential ventilation. The first task within the project will be the development

of a project plan that specifies the simulations

to be performed and the output analysis. The

second task will include the simulations

themselves, analysis of the results, comparison

of the results with the results of the CPSC

study, and preparation of a final report.

Based on the houses and pollutant sources used

in the CPSC project, BFRL will perform

CONTAM simulations to determine the indoor

air quality impacts of several residential

ventilation systems. The systems to be

considered wall include whole house exhaust

systems with distributed fresh air inlets, whole

house exhaust systems relying on envelope

leakage for intake, and outdoor air intake ducts

that operate with local exhaust systems. A

number of control modes will be considered

with these systems including various

pre-determined schedules of operation. Besides

the contaminants simulated in the CPSC study,

this work will consider occupant-generated

pollutants using carbon dioxide as a surrogate.

Also, long term simulations (up to 1 year) will

be considered as an alternative to the 24-h

simulations employed previously. The results of

the analyses will be analyzed for average

ventilation rates, distributions of ventilation

rates and contaminant concentrations, and

various measures of occupant exposure to

contaminants.

Recent Results

New project

Carbon Monoxide Detector Location

in Residential Buildings

Principal Investigator

Andrew IC Persily

Building Environment Division

301-975-6418

Sponsor

National Fire Protection Research Foundation

Objective

To analyze the distribution of carbon monoxide

in family living units as it relates to the

installation of carbon monoxide detectors.

Problem

Low-cost carbon monoxide detectors have

become available for use in warning building

occupants of elevated carbon monoxide levels

from a variety of sources. While the use of

these devices is increasing, questions exist

regarding the appropriate number of detectors

and their locations in a home. There also are questions about their location within the

individual room. The lack of sufficient

information regarding the distribution of carbon

monoxide in buildings makes it difficult to

develop recommendations for detector

installation. Technically based

recommendations are needed by the consumers

who purchase and install these devices, the

manufacturers who develop installation

instructions, and code-writing organizations

who may develop requirements for their

installation.

Approach

During FY 1996, BFRJL will perform Task 1 of

three tasks:

1. Perform a literature review, a technical

analysis of the issue, and the development of

a recommended study plan that will involve

experimental studies and computer

modeling.

2. Perform the experimental and modeling

work in single rooms.

3. Perform the experimental and modeling

work in whole buildings.

The Task 1 literature review will consist of

88
r

assembly and analysis of published literature Recent Results

and other work in progress related to the issues New project

of air movement and contaminant distribution

in family living units, carbon monoxide sources,

and carbon monoxide concentration

measurements. As part of this effort, input

from the National Fire Protection Research

Foundation Technical Advisory Committee

(TAG) will be sought for additional materials.

The analysis of this information wall focus on

the following issues: likely sources of carbon

monoxide and their characteristics, air and

contaminant distributions in family living units,

building factors affecting these distributions,

appropriate modeling approaches, and

measurement protocols. A report on the results

of the literature review will be prepared for

review by the TAG.

Following completion of the literature review, a

technical analysis will be performed to identify

those specific factors to carbon monoxide

distribution in family living units and a draft

study plan recommendation will be developed

for Tasks 2 and 3. The technical analysis will

synthesize the technical findings of the

literature review about what is known about

carbon monoxide distributions and the factors

that impact these distributions. The analysis

also will identify the variables to be considered

in the study plan including, but not limited to,

house type and configuration, HVAG system

type, and carbon monoxide source

characteristics. Based on this analysis, a draft

study plan recommendation will be developed

to make field tests of carbon monoxide

distributions in a small number of family living

units and to supplement these tests with

simulations under a larger number of

circumstances. The objective of the study will

be to obtain some insight into the issue of

carbon monoxide distribution within family

living units and into the factors affecting these

distributions. A report containing the results of

the technical analysis and the draft study plan

recommendation wall be prepared for review by

the TAG. Based on the comments received by

the TAG on the draft study plan

recommendation, a final study plan for Tasks 2

and 3 will be prepared.

89

1

i

BUILDING ENVIRONMENT

DIVISION

MECHANICAL SYSTEMS

AND CONTROLS
i
Communication Protocols for

Building Controls

Principal Investigator

Steven T. Bushby

Building Environment Division

301-975-5873

Sponsors

National Institute of Standards and Technology

Department of Energy

Federal Emergency Management Program

Office of Energy Efficiency and Renewable

Energy

Objective

To develop, evaluate, and produce conformance

tests for communication protocol standards on

the open exchange of information between

equipment from different control vendors and

between different levels of control in hierarchal

and distributed building management systems

(EMS).

Problem

Today's direct digital control (DDC) systems

employ proprietary communication protocols

that prevent systems supplied by different

manufacturers from communicating with each

other. This has resulted in "captive customers"

who, upon buying a control system, are unable

to upgrade or expand it without going back to

the same manufacturer. This lack of

communication capability between control

systems made by different manufacturers also

prevents the building owner from obtaining the

most capable building service by not allowing

him to choose, regardless of the manufacturer,

the best EMCS system, the best digital controllers, the best security system, the best fire

detection system, or the best telecommunications system.

Approach

During FY 1996, BFRL will perform four tasks:

1. Administer and participate with industry

partners in a BACnet Interoperability

Testing Consortium. The Consortium will:

assist control system manufacturers to

verify the correctness and interoperability

of their. proprietary BACnet

implementations;

- verify the technical soundness of the

BACnet protocol;

identify errors or omissions in the

BACnet protocol specification;

identify ambiguities in the BACnet

protocol that might lead to

implementations that cannot interoperate

and;

develop insight into testing requirements

which should be included in a future

ASHRAE standard for testing

conformance to BACnet.

2. Develop Tools that can be used to establish

an industry-run BACnet certification

program.

3. Establish a BACnet test-bed demonstration

project in a GSA building in San Francisco.

4. Initiate work on international

standardization of BACnet through ISO TC

205.

5. Begin work on expanding BACnet to

integrated building services, including life safety, security, and transportation.

It is expected that the results from this research

will: 1. expand the acceptance of BACnet

technology into the areas of lighting control, life safety systems, security, and elevator control; 2.

achieve international standardization of the

BACnet protocol; and 3. establish an industry- run BACnet certification program based on

recognized testing standards.

Recent Results

Assisted ASHRAE to publish the BACnet

protocol as ANSI/ASHRAE Standard 135-1995,

BACnet - A Data Communication Protocolfor

Building Automation and Control Network,

December 1996.

Created a new subcommittee of ISO TC 205 to

address international standardization of

building control system protocols.

93
Real Time Fault Detection and

Diagnostics

Principal Investigator

John House

Building Environment Division

301-975-5874

Sponsors

National Institute of Standards and Technology

Department of Energy

Office of Energy Efficiency and Renewable

Energy

Johnson Controls

Objective

To develop and demonstrate methods for

controlling and performing fault detection and

diagnostics (FDD) on mechanical equipment

and systems in real time and to participate in

the International Energy Agency (lEA) Annex

25 Corrunittee on Real Time Simulation of

HVAC - Systems for Building Optimization,

Fault Detection and Diagnostics (BOFD).

Problem

Modern buildings are being designed with

increasingly complex operating systems that

have seemingly limitless capabilities for

monitoring and controlling the conditions in

the building. Building operators are not always

able to monitor and process the enormous

amounts of data generated. Hence, there is a need for robust FDD tools that can be used to

assist the building operator and ensure that the

system is operating in the manner in which it was designed. Furthermore, there is a need to

develop new control strategies that can take

advantage of the capabilities offered by digital

control to perform system control rather than

the component type of control that has

traditionally been used with pneumatic

controllers. The development of advanced

control strategies and methods for FDD are expected to reduce energy use in buildings,

improve occupant comfort and health, and

reduce equipment wear.

Approach

During FY 1996, BFRL will work with industry

and academia to develop and test advanced

control strategies and methods for FDD.

Computer simulations using HVACSIM-I- will

be used initially to compare the new control

strategies with traditional strategies. An

experimental validation of the strategies will

then be performed using the VAV air handling

system in the BFRL FDD Laboratory.

Depending on availability, further validation

work may be performed using the Temperature

Control Module (TCM) in the large

environmental chamber. BFRL will also work

with Purdue University to demonstrate and

compare BFRL and Purdue methods for on-line

fault detection and diagnostics of the VAV air

handling system in the BFRL FDD Laboratory,

and to apply BFRL methods to a chiller system.

Annex 25 will be coming to a close in the

upcoming year; however, it is anticipated that

another Annex will follow with the objective to

demonstrate the FDD methods developed in

Annex 25 in real buildings and to develop

algorithms for implementing these methods.

BFRL will examine the feasibility of using the

TCM as a first phase test-bed demonstration

project.

In addition, a BACnet test-bed demonstration

project will be implemented in a GSA operated

building in San Francisco. This site will be used

in future years to evaluate the benefit of energy

management systems, advanced/optimal

building system control strategies, and FDD

methods and applications. BFRL will examine

the feasibility of using this building for the

second phase test-bed for the demonstration

project.

It is expected that the results of this work will:

1. produce a hierarchical framework for FDD in

buildings; 2. demonstrate viability of FDD

methods in real buildings by working with the

other Annex 25 participants and industry; 3. develop and demonstrate advanced control

strategies (including optimal control) for

buildings through linkages with industry; and 4. develop a framework for implementing FDD

methods and control strategies in BACnet

energy management and control systems.

94
Recent Results

Lee, W.Y., Park, C. and Kelly, G.E., "Fault

Detection of an Air Handling Unit Using

Residual and Recursive Parameter Identification

Methods," y4SHRA£ Transactions, vol.102, pt. 1, 1996.

Lee, W.Y., House, J.M., Park, C, and Kelly,

G.E., "Fault Diagnosis of an Air Handling Unit

Using Artificial Neural Networks," ASHRAE

Transactions, vol. 1, pt. 1, 1996.

Test Procedures for Furnaces,

Boilers, and Integrated Appliances

Principal Investigator

Stanley T. Liu

Building Environment Division

301-975-5880

Sponsor

Department of Energy

Office of Energy Efficiency and Renewable

Energy

Office of Codes and Standards Division

Objective

To provide equitable testing and rating

procedures for determining energy performance

of furnaces, boilers, and integrated appliances.

Problem

In FY 1995, the furnace industry raised an

issue about the calculation of the AFUE for gasfired, two-stage modulating furnaces. When

applying the DOE test procedure for the AFUE

value based on test results at the rated and the

low firing rates, the AFUE value based on the

two-stage calculation procedure was lower than

the AFUE value based on the single stage

calculation under the low firing rate condition.

The discrepancy between the two AFUE values

was from 0.5 to 1 percentage points with the

single stage, low firing rate calculation giving

the higher value. This was opposite to what was

expected. A study of the calculation procedures

is needed to find the cause of the problem and

to develop possible corrections to the

calculation procedures.

During FY 1994-95, BFRL assisted DOE in

evaluating a petition for waiver submitted by

the York International Corp. on the

determination of the power burner draft factor

by the optional tracer gas procedure. The units

involved in the waiver request were induced

draft, gas-fired, outdoor furnaces. Because the

units are installed outdoors, there is no

requirement for the installation of flue pipe to

the flue collar during the rating test for AFUE

by the existing DOE furnace test procedure.

Since most outdoor furnaces now on the market

are induced draft type, a reliable and repeatable

95
test procedure is required in conducting the

tracer gas test and incorporating it into DOE's

furnace/boiler test procedure for this type of

outdoor furnaces.

During FY 1995, BFRL assisted DOE evaluate

public comments received after the publication

in the Federal Register (in January 1995) about

the proposed revision to the DOE test procedures on residential furnaces/boilers,

vented home heating equipment and pool

heaters. A revised preamble and test procedures

for furnace/boiler, vented home heating

equipment and pool heaters based on the public

comments and DOE's instructions were

transmitted to DOE. BFRL will continue to

assist DOE in completing the revised test procedures so they can be published as a final

rule.

5. Complete recommended test procedure for

evaluating the annual performance and cost

of operation of Type I and Type II combined

space/water heating appliances and assist

DOE in preparing a Proposed Rule Making

on this product.

Recent Results

Liu, S. T., Kelly, G. E., and Terlizzi, C. P., Performance Testing of a Family of Type 1 Combination Appliances , NISTIR5626, National

Institute of Standards and Technology, April

1995.

Approach

During FY 1996, BFRL will perform the

following tasks:

1. Continue assisting DOE publish the Final

Rule for furnaces/boilers and vented home

heating equipment.

2. Investigate and evaluate the various

parameters in the furnace test procedure

affecting the calculation of the AFUE for

single and two stage modulating furnaces to

reconcile the difference in AFUE values

produced by the existing calculation

procedure. Sensitivity studies will be

conduct on the discrepance in the AFUE

values between the single stage furnace and

two-stage modulating furnace to determine

various differences between the two types of

furnaces and identify the cause of the

difference and develop possible corrections

to reconcile the difference in the AFUE

values.

3. Conduct laboratory tests on an induced

draft, outdoor furnace for the development

of a tracer gas test procedure for the

determination of the power burner draft

factor. Tests will be performed on a test unit obtained from the York Corporation to

develop the needed tracer gas procedures.

4. Assist DOE to prepare responses to Requests

for Waivers on furnace/boiler and vented

home heating equipment and draft Federal

Register Notices of proposed Rule Making.

96
Commercial Furnace/Boilers, Central

Air Conditioners, Heat Pumps, and

Water Heaters

Principal Investigator

Stanley Liu

Building Environment Division

301-975-5880

Sponsor

Department of Energy

Office of Energy Efficiency and Renewable

Energy

Office of Codes and Standards

Objective

To provide equitable testing and rating

procedures for determining energy performance

of commercial furnace/boilers, central air

conditioners, heat pumps, and water heaters.

Problem

The Energy Policy Act of 1992 (EPACT)

requires DOE to develop test procedures for the

energy performance of certain class of

commercial heating and cooling equipment and

corruTvercial hot water heaters. The Act specifies

the ANSI/ASHRAE Standard 90.1-1989 as the

reference document to determine the energy

performance standard. ASHRAE 90.

1

referenced existing industry standards for the

testing of a product. For water heaters no

industry standard or test procedure is referenced for unfired hot water storage tanks.

ASHRAE Standing Standard Project

Committee (SSPC 90. 1) has addressed some

unspecified or unclear procedures after

ASHRAE Standard 90.1-1989 was published.

Proposed updating and revision to ASHRAE

90. 1 is continuing. These issues need be

addressed to develop equitable test and rating

procedures for the EPACT-covered commercial

products. )

Approach

During FY 1996, BFRL will continue to assist

DOE develop, revise, and complete the draft

DOE test procedures for the EPACT-covered

products as required by DOE's proposed

rulemaking process. As ASHRAE continues its updating of the ASHRAE 90. 1 , BFRL will

participate and provide input on the revision

process. BFRL will participate in the ASHRAE

SPC 155P's effort for the development of test procedure for all type of commercial space

heating boilers. The computer program for

commercial boilers will be used to simulate the

performance of the boilers to help in developing

the test procedure. The application of the

ANSI/ASHRAE Standard 94.3-1986 for unfired

hot water storage tanks and a possible simpler

optional procedure will be evaluated.

Recent Results

Provided letter reports to the sponsor on the

various tasks including deficiencies of the

ASHRAE 118.1-1993 Standard for

boiler/storage tank systems.

97
Test Procedures for Heat Pumps and

Air Conditioners

Principal Investigator

Brian Dougherty

Building Environment Division

301-975-6396

Sponsor

Department of Energy

Office of Energy Efficiency and Renewable

Energy

Office of Codes and Standards

Objective

To provide equitable testing and rating

procedures for determining energy performance

of heat pumps and air conditioners.

Problem

The Energy Policy and Conservation Act (PL

94-163) (EPCA), as amended, requires the

Department of Energy (DOE) to prescribe test and rating procedures and minimum

performance standards for various residential

appliances. In addition, the 1987 amendment

to EPCA requires analysis of any test procedure

amendments to determine their effect on

minimum efficiency standards. DOE has, since

1975, relied on BFRL to assist in the

development of the test and rating procedures.

Approach

During FY 1996, BFRL will continue its efforts

toward generating a metric version of the DOE

central air conditioner and heat pump test procedure. Based on industry feedback to date,

BFRL is attempting to structure the metric

version of the DOE test procedure such that

conducting the DOE procedure satisfies the ISO

requirements. BFRL v^U continue its participation at ARI and ASHRAE meetings

where metrification issues are discussed. Soonto-be-completed ETL steady-state and cyclic

tests will be used to quantity how capacity and

Cq are affected when evaluated at the present

8 °C test condition versus the expected metric

replacement. Many manufacturers want to

have cyclic testing eliminated from the test procedure.

BFRL will complete revisions to DOE's test procedure for central heat pumps and air

conditioners before the rulemaking is published,

summarize the major revisions in a separate

letter report, and assist DOE in resolving

comments received afterwards. BFRL will

generate a final version of the test procedure.

BFRL will assist DOE review comments

received from its request for waiver submitted

by Nordyne on their line of combined heat

pump-water heating appliances and will work

with DOE and Nordyne in making

modifications to the Nordyne proposed

method. Work includes integrating the

Nordyne waiver, ASHRAE Standard 137, and

the BFRL proposed test method into a single

document for use by DOE in a proposed

rulemaking on a combined appliance test procedure. Test data will be needed before final

decisions can be made to the final content of

the proposed test procedure.

BFRL will work in the area of testing and rating

methods for residential thermal storage heat

pumps. It is hoped that collaboration will occur with Lennox Industries and UHR, two

manufacturers who recently manufactured

thermal storage units.

Recent Results

Written and provided internal reports to DOE

on mixed system rating methods for two coil

manufacturers, Unico System and Mestek; on

recommended modifications to two ASHRAE

Standards (16 and 58) referenced in DOE test procedures; and on rating methods for dual-fuel

heat pumps and recommendations for a workshop on dual-fuel and multifunction

appliances.

Contributed significant technical information to

development of ASHRAE Standard 137P; to be

published following approval by ASHRAE

Board of Directors.

98
Test Procedures for Lighting

Fixtures and Systems

Principal Investigator

Steve Treado

Building Environment Division

301-975-6444

Sponsor

Department of Energy

Office of Energy Efficiency and Renewable

Energy

Office of Codes and Standards

Objective

To provide equitable testing and rating

procedures for determining energy performance

of lighting fixtures and systems.

Problem

The Energy Policy and Conservation Act (P 94-

163) (EPCA), as amended, required the

Department of Energy (DOE) to prescribe test and rating procedures and minimum

performance standards for various residential

appliances. In additional, the 1987 amendment

to EPCA requires analysis of any test procedure

amendments to determine their effect on

minimum efficiency standards. DOE has, since

1975, relied on BFRL to assist in the

development of the test and rating procedures.

The Energy Policy Act of 1992 (EPACT)

contained many provisions relating to lighting

equipment, including labeling and minimum

standards for incandescent and fluorescent

lamps. The implementation of these provisions

required the development or specification of

appropriate test procedures, and a rigorous set of definitions for covered products and

exemptions.

Approach

During FY 1996, BFRL will continue to provide

technical support and assist in DOE rulemaking

activities. It is anticipated that particular

emphasis will be required for evaluating new or modified lamp products as manufacturers begin

to adapt their product lines in response to the

implementation of the minimum standards for

lamps. This will require interpretation of

whether a new lamp is a covered product, and

whether the existing test procedures are adequate for determining their performance. In

addition, BFRL researchers will monitor and

verify light output and energy usage of available

lamps to support review and possible changes to

existing fluorescent and incandescent lamp

standards and support evaluation of new

standards for compact fluorescent and

incandescent lamps. Researchers also will

monitor activities of the Lighting Collaborative

related to the voluntary luminaire labeling

program, and will participate in the lES Testing

Procedures Committee, and support NIST's

National Voluntary Laboratory Accreditation

Program on Energy Efficient Lighting

Equipment.

BFRL will conduct laboratory experiments to

determine if and how a test procedure could be

used to diagnose and characterize the electrical

properties of fluorescent lamps, for

identification of the lamp type instead of

depending solely on manufacturers

designations. The laboratory measurements

would investigate methods for determining

lamp type from an objective test. If feasible, a

test procedure would then be developed.

The laboratory will develop a method for

classifying long-life lamps based on

measurements, and investigate the

accommodation of long-life tungsten-halogen

incandescent reflector lamps in the lamp

standards program. Similarly, BFRL researchers

will evaluate vibration service tungsten-halogen

incandescent reflector lamps to develop a test procedure for determining or verifying their

vibration resistance.

Recent Results

Test procedure for general service fluorescent

and incandescent reflector lamps were refined

and incorporated into DOE rule making.

Refined and incorporated test procedures for

general service fluorescent and incandescent

reflector lamps into DOE rule making.

99
Plumbing Test Procedures

Principal Investigator

Stephen J. Treado

Building Environment Division

301-975-6444

Sponsor

Department of Energy

Office of Energy Efficiency and Renewable

Energy

Office of Codes and Standards

Objective

To develop test procedures as required for

plumbing products covered under The Energy

Policy Act of 1992 (EPACT).

Problem

EPACT specifies performance standards for

many plumbing products, including toilets,

urinals, showerheads, and faucets. The

American Societies of Mechanical Engineers

(ASME) test procedures for measurement of

hydraulic performance area also specified and

are to be adopted by the DOE. While these

test procedures are in general sufficient for their

intended purpose, the introduction of new

plumbing products and designs, and the

interpretation and application of the specific

testing provisions will require DOE to

continuously monitor these changes and their

effects on the Department's test procedures for

plumbing products.

Approach

During FY 1996, BFRL will continue to provide

technical support and liaison with

manufacturers, LBL, and related organizations

regarding the test procedures and minimum

standards for plumbing products. BFRL will

meet with manufacturers, attend industry group

meetings and review revised standards to

determine whether they are more or less

stringent than before. Specific activities will

include supporting the ongoing DOE

rulemaking, evaluating the revised ASME Al 12

18.1 for equivalency, reviewing and analyzing

the revised ASME Al 12 19.6, and providing

general technical support.

BFRL will, if deemed necessary, conduct an

assessment of the sampling plan and basic

model definition to ensure statistically valid

performance data without an undue burden on

the manufacturers. The industry supports the

testing of two units for each basic models for

certification surfaces. BFRL will collect

information/data from the plumbing industry

and conduct work, to determine the soundness

of the industry proposal, or develop and refine a

valid statistical sampling, as required.

Recent Results

Provided technical support, review, and

oversight for DOE rulemaking activities for

plumbing products.

100
Development of Revised Test

Procedures for Compact

Refrigerators

Principal Investigator

James Kao

Building Environment Division

301-975-5871

Sponsor

Department of Energy

Office of Energy Efficiency and Renewable

Energy

Office of Codes and Standards

Objective

To conduct investigation on small refrigerators

to determine if the DOE test procedure should

be revised.

Problem

DOE's obtained information from some

commercial test laboratories, in the past year,

showed the energy test results on compact

refrigerators in volumes of 0.12 m' or less

indicated repeatability problem. However, the

accuracy of this information is not certain.

Further investigation to confirm or deny its validity is needed.

Approach

During FY 1996, BFRL will perform the

following tasks:

1. Inquire with manufacturers and test laboratories to determine if an energy test is a problem for refrigerators in volumes of

0.12 m^ or less.

2. Evaluate the DOE energy test procedure to

determine if the test procedure causes

reliability problems in energy tests for small

refrigerators.

3. If appropriate, develop a plan to determine

the extent of the problem. One possible

approach is to test the same refrigerators at

different test laboratories, such as the

refrigerator manufacturer, Inchcape, CSA,

and NIST (a round robin approach).

Recent Results

Completed tests on two refrigerator-freezers to

determine the energy effects from room

temperature, room humidity, anti-sweating

heater, door openings, and inside temperature

settings (for both food and freezer

compartments).

103
Development of Revised Test

Procedures for Clothes Washers

Principal Investigator

James I<ao

Building Environment Division

301-975-5871

Sponsor

Department of Energy

Office of Energy Efficiency and Renewable

Energy

Office of Codes and Standards

Objective

To provide equitable testing and rating

procedures for determining energy performance

of clothes washers.

Problem

The Energy Policy and Conservation Act (PL

94-163) (EPCA), as amended, requires the

Department of Energy (DOE) to prescribe test and rating procedures and minimxim

performance standards for various residential

appliances. In addition, the 1987 amendment

to EPCA requires analysis of any test procedure

amendments to determine their effect on

minimum efficiency standards. BFRL had,

since 1975, assisted DOE in the development of

the test and rating procedures.

Approach

During FY 1996, BFRL will evaluate clothes

washer to gather basic energy performance data.

These data will be analyzed to assist in future

revision of test procedures and addressing

possible manufacturers' requests for waivers.

Last year, DOE announced a Proposed Rule for

revising the clothes washer test procedure. In

the same year, the Association of Home

Appliance Manufacturers' (AHAM) proposed a

revised clothes washer test procedure to be used

for the 1999 DOE test procedure revision.

Both documents added measurement

requirements for water consumption, energy

consumption for test cloths moisture removal,

and testing of water-heating clothes washer.

The AHAM proposal also incorporated certain

test revisions in anticipation of new control

features, such as automatic fill control, that

manufacturers may adapt in their new clothes

washers. BFRL will review these documents

and associated public hearing comments, and

make recommendations to DOE based on

laboratory test results and analysis.

Recent Results

Results were provided to DOE as letter reports.

104
Development of Revised Test

Procedures for Clothes Dryers

Development of Revised Test

Procedures for Dishwashers

Principal Investigator

James I<ao

Building Environment Division

(301) 975-5871

Sponsor

Department of Energy

Office of Energy Efficiency and Renewable

Energy

Office of Codes and Standards

Objective

To provide equitable testing and rating

procedures for determining energy performance

of clothes dryers.

Problem

The Energy Policy and Conservation Act (PL

94-163) (EPCA), as amended, requires the

Department of Energy (DOE) to prescribe test and rating procedures and minimum

performance standards for various residential

appliances. In addition, the 1987 amendments

to EPCA requires analysis of any test procedure

amendments to determine their effect on

minimum efficiency standards. NIST has, since

1975, assisted DOE in the development of the

test and rating procedures.

Approach

During FY 1996, BFRL will evaluate clothes

dryers to gather basic energy performance data.

Dryers included in these tests procedure are a conventional dryer and a condenser dryer.

These data are analyzed to assist future revision

of DOE test procedures and addressing possible

manufacturers' requests for waivers.

The recent development of microwave

commercial clothes drying shows promising

potential. If the manufacturing and marketing

of similar clothes dryers for residential use appear warranted, BFRL will investigate the

possibility of testing such dryers in the

laboratory.

Recent Results

Results were provided to DOE as letter reports.

Principal Investigator

Natascha Castro

Building Environment Division

301-975-6420

Sponsor

Department of Energy

Office of Energy Efficiency and Renewable

Energy

Office of Codes and Standards

Objective

To conduct tests on residential dishwashers to

assess its efficiency in energy consumption and

performance and determine whether revisions are warranted to upgrade the procedure.

Problem

The current DOE test procedure was developed

more than ten years ago and does not have

provisions for testing dishwashers with adaptive

controls. Therefore, dishwashers equipped with

these and other recent innovations cannot be

accurately tested. The main features that

contribute to improved energy performance are

better thermal insulation, improved motor

efficiency, better water distribution, improved

food filtering, and improved fill controls (using

float controls instead of timer controls). Other

items that have energy reducing potential are improved water heating in water-heating

dishwashers and innovative control schemes. In

light of energy consumption reductions in

dishwashers over the past decade, review of the

current test procedure is in order.

Approach

During FY 1996, BFRL will test an adaptive

control dishwasher, gathering base energy and

water consumption data. Performance-based

tests will be run on the conventional and

innovative dishwasher using soiled test loads

according to the Association of Home

Appliances Manufacturers (AHAM) and lEC

standards. The principal investigator will

conduct a survey including a literature search of

controls used in appliances to assess system

operation and limitations. Work, will continue

105
on the test procedure and will be focused on

developing a method of testing energy and

water consumption of innovative dishwashers

for use with the 1999 standards.

The results of this research are expected to form

the basis of new significant performance-based

test and rating procedures for dishwashers and

further encourage manufacturers to use control

features and designs that reduce energy

consumption.

Recent Results

Examined AHAM and International test procedures for their respective approaches to

performance-based testing and energy

consumption testing.

Automated the data acquisition for energy

consumption, water consumption, and other

data pertinent to dishwasher analysis and

procured an adaptive control dishwasher.

Development of Revised Test

Procedures for Pool and Spa Heaters

Principal Investigator

Stan Liu

Building Environment Division

301-975-5880

Sponsor

Department of Energy

Office of Energy Efficiency and Renewable

Energy

Office of Codes and Standards

Objective

To provide equitable testing and rating

procedure for determining energy performance

of pool and spa heaters.

Problem

In FY 1993, DOE modified the test procedure

for pool and spa heaters to include a calculation

of an energy factor and published the procedure

in the Federal Register as a Proposed

Rulemaking on August 23, 1993 for public

hearing and comments. The test procedure

covers only gas- and oil-fired pool heaters. It does not address an electric resistance type

heater or the heat pump pool heaters that were

recently introduced into the marketplace. A

revised test procedure is needed to include the

installation, measurements, test methods, and

calculation procedures for the electric resistance

type and the heat pump pool heaters.

Approach

During FY 1996, BFRL will continue to provide

comments and suggestions to DOE by

incorporating technical data for fossil fueled

and electrical operated heaters into a revised

DOE test procedure for pool and spa heaters.

Recent Results

BFRL assisted DOE evaluate public comments

and prepared the draft final rule in response to

the comments received.

Contributed to the draft ASHRAE SPC 146P

Standard for pool and spa heaters.

106
1

BUILDING ENVIRONMENT

DIVISION

THERMAL MACHINERY

Thermodynamic Performance of

Alternative Refrigerants and

Refrigerant Mixtures

Principal Investigators

Peter I. Rothfleisch

Building Environment Division

301-975-5868

David A. Didion

Building Environment Division

301-975-5881

Piotr A. Domanski

Building Environment Division

301-975-5877

Sponsor

National Institute of Standards and Technology

Objective

To quantify the performance potentials and

limitations of a zeotropic refrigerant mixture in a residential air-to-air heat pump.

Problem

A zeotropic mixture, as a working fluid for

refrigeration machines, offers two basic

advantages: 1. a gliding saturation temperature

during the phase change (i.e., evaporation and

condensation) and 2. an opportunity to vary

the circulating composition of the working fluid

and, thus, the system's capacity. In spite of

these advantages, equipment manufacturers are wary with using zeotropic mixtures because of

the difficulty in servicing the equipment after a

refrigerant leak; since the vapor phase and

liquid phase have different compositions, a leak

of one of the phases will result in a composition

change of the working fluid. The tasks covered

by this work statement address these three

aspects (potentials and limitations) of zeotropic

mixtures in an air-conditioning system.

Approach

Before FY 1993. BFRL conducted a composition-shifting study with a passive

system (i.e., the accumulator) which yielded

rather limited results. During FY 1993 and FY

1994, an active distillation column was

designed and constructed. This design was

unique and a patent application was filed. In

FY 1995, the possibility of an increased

composition shift was verified in laboratory

tests, and the results were reported in NISTIR

5689. The results were sufficiently good to

warrant a modeling effort of a heat pump with a

distillation column (it will be performed under a

separate project sponsored by the Electric

Power Research Institute).

During FY 1996, BFRL will perform additional

tests with R-407C (R-32/125/134a (23/25/52))

to completely remove the high-boiling R-134a

from the circulating stream and bring the

system's capacity to its maximum limit. The

results will be reported in a conference paper.

BFRL has developed several sophisticated

models verified by laboratory tests and then

used in various BFRL studies. In FY 1995, a

theoretical model CYCLE D was prepared for

the Standard Reference Data Program (SRD)

and is now distributed as Database 49. The

following work is planned on two other models

to make them available for general use through

the SRD program:

REFLEAI<4 a model for simulating leak^recharge

processes and for calculating the resulting

change of mixture composition in the system.

The model will be fully debugged and

documented. It also will be equipped in a userfriendly. Visual Basic interface.

CYCLE- 1 1; a model for determining the

performance potentials and tradeoffs for

different refrigerant and mixtures in different

heat exchanger configurations. In the FY 1996,

the existing modeling limitations for cross-flow

heat exchanges will be removed and the code

will be fully debugged. In FY 1997, CYCLE- 1

1

will be documented, furnished in a user-friendly

interface, similar to that developed for SRD 49

(CYCLE D), and will be readied for SRD

distribution. In FY 1996, BFRL will use the

upgraded code to study the relative merits of

cross-, counter, and parallel-flow heat transfer

for low- and high-glide zeotropes. The goal of

the study will be to quantify the COP potentials

for zeotropes as a function of temperature glide,

temperature lift, and glide non-linearity.

109
Recent Results

Rothfleisch, P., A Simple Method of Composition

Shifting with a Distillation Column for a Heat

Pump Employing a Zeotropic Refrigerant Mixture,

NISTIR 5689, National Institute of Standards

and Technology, July 1995.

Kim, M. S., and Didion, D., "Simulation of

Isothermal and Adiabatic Leak Process of

Zeotropic Refrigerant Mixtures," HVACSlR

Research, Vol. 1, No. 1, 1995 .

Kim, M. S., and Didion, D., "Simulation of a Leak/Recharge Process of Refrigerant Mixtures,"

HVACSlR Research, Vol. 1, No. 3, 1995.

Chi, J., Didion, D., and Domanski, P., CYCLE D:, NIST Vapor Compression Cycle

Design Program, NIST Standard Reference

Database 49, National Institute of Standards

and Technology, May 1995.

Thermodynamic Performance of

Natural Fluids as Alternative

Refrigerants

Principal Investigators

David A. Didion

Building Environment Division

301-975-5881

Peter I. Rothfleisch

Building Environment Division

301-975-5868

Piotr A. Domanski

Building Environment Division

301-975-5877

Sponsor

National Institute of Standards and Technology

Objective

To evaluate the thermodynamic and heat

transfer performance of natural fluids as a working medium for refrigeration systems.

Problem

With the ozone crisis eliminating the use of

chlorine in the manufacturing of refrigerants,

the industry is rapidly moving toward the use of

hydrofluorocarbon compounds. This

conversion has been and continues to be the

most dramatic change this industry has ever

faced. On the horizon looms the global

warming crisis and the carbon-fluorine bond of

the alternative refrigerants cause them to have a high Global Warming Potential (GWP). It is the opinion of many that "natural" fluids be

used as refrigerants. That is, fluids found in

nature or are in such abundance in the

atmosphere already that the marginal difference

the refrigerant supply would be insignificant

(e.g., carbon dioxide, hydrocarbons, ammonia,

water vapor). Although these fluids have been

used as refrigerants in the past, they (except

ammonia in industrial applications) have been

disregarded for various safety or efficiency or economic reasons.

Approach

During FY 1996, BFRL will evaluate natural

fluids as alternative refrigerants. This work

110
requires system performar\ce analysis via

computer modeling, laboratory system

(breadboard) measurements and heat transfer,

particularly evaporative and condensing flows,

coefficient determination. The properties of

these natural fluids are radically different from

halogens and significant hardware changes are required and fundamental changes to the

thermodynamic cycle and processes.

The main thrust of this project is the evaluation

of the concept of a water-to-water heat pump.

In such a system, the refrigerant is confined in

the outdoor section, and the inhabited structure

is heated or cooled by a secondary refrigerant.

Because of a small refrigerant charge and its location outside the house, flammable

refrigerants could be used. In the early analysis

stage, this concept was evaluated using a modified version of CYCLE- 1 1 . Last year a new

apparatus was designed and constructed for

system testing with flammable refrigerants.

During the next stage, tests will be performed at operating conditions typical for cooling and

heating conditions of a ground-source heat

pump. The fluids tested will include: R-22 (as a reference), propane, and propane/butane

rruxture. In addition, R-32/152a mixture will be

evaluated because it has a low GWP and high

COP. The use of a secondary refrigerant will

inflict a performance penalty due to the

increased temperature lifts. The goal of the

study is to offset this penalty by glide-matching

using zeotropic mixtures and by excellent

transport properties of the selected refrigerants.

Aside of evaluation of the water-to-water heat

pump concept, this project covers upgrading of an air-to-air heat pump model (HPSIM) so it could cover refrigerant mixtures comprising up

to five components. Several modifications will

be made to better represent newer heat transfer

surfaces introduced to the marketplace in the

recent years.

Recent Results

Domanski, P., Didion, D., Mulroy, W., Parise,

J., "A Simulation Model and Study of Hydrocarbon

Refrigerants for Residential Heat Pump Systems,

IIR Conference on Natural Working Fluids in

Refrigeration and Air-Conditioning, Hannover,

Germany, 1994.

Calorimetric and Visual Study of

Heat Transfer Enhancements with

Alternative Refrigerants

PrincipaI In ves tiga tors Mark A. Kedzierski

Building Environment Division

301-975-5282

David A. Didion

Building Environment Division

301-975-5881

Piotr A. Domanski

Building Environment Division

301-975-5877

Sponsors

National Institute of Standards and Technology

Department of Energy

Office of Building Technologies

Building Equipment Division

Electric Power Research Institute

Customer Services Division

Trane Company

Objective

To calorimetrically and visually investigate twophase heat transfer of alternative refrigerants.

Problem

The cost of manufacturing or operating a water

chiller could be significantly reduced by

improving the boiling performance of 1,1-

Dichloro-2,2,2-Trifluoroethane (R123). Liquid

additives can be an economical means of

enhancing boiling performance. Liquid

additives could make it possible to reduce

manufacturing cost because a chiller would

require fewer tubes to meet the same capacity.

Operating costs of new or existing chillers could

be reduced since the additive may improve the

efficiency of chillers. Typically, binary mixtures

exhibit a boiling performance degradation

compared to the pure components (Shock,

1982). Consequently, liquid additives that

significantly enhance boiling performance are

rare.

Ill
Approach

During FY 1996, BFRL will perform two tasks;

the first will focus on additives for R123 and

the second will focus on in-tube evaporation

and condensation of R22 replacements. The

first BFRL additive study showed that n-Hexane

enhances the evaporator performance when

added to R123 by 1 percent mass. The Trane

Company (Glamm, 1995) verified the

evaporator enhancement in a full chiller test. Trane Company researchers also observed a performance degradation in the condenser in

the same chiller tests. The second BFRL study

furthered the understanding of the governing

enhancement mechanism. Overall, the new

understanding showed that it is plausible that

any hydrocarbon might enhance the boiling

performance of R123. If a higher molecular

weight (lower vapor pressure) hydrocarbon is used as an additive, it will have less of a tendency to travel to the condenser.

Consequently, the condenser performance

would be unaffected by the additive if the

additive remained in the evaporator.

The first task is to measure the pool boiling

heat transfer performance of R123 and mixtures

of low vapor pressure hydrocarbons. The

hydrocarbons to be tested as additives are: n- Heptane, n-Octane, n-Nonane, and n-Decane.

The second task is to measure the condensing

performance of the additives that enhance the

heat transfer. It is expected that the condensing

performance with the dilute solutions of the

lower vapor pressure hydrocarbons and R123

will remain close the pure R123 performance.

However, additives that enhance the boiling

performance of R123 can still be used to

improve cycle efficiencies even if a condensing

degradation is observed. Consequently, the

condensation data will be useful in determining

the condenser area increase required to

compensate for performance degradation.

A new condensing rig will be built of a design

similar to the pool boiling rig. Both the boiling

and condensing rigs permit simultaneous accurate heat-transfer-coefficients measurements

and visual observations with high-speed film.

Another unique aspect of the additive-boiling

measurements is that a laser will be used to

gather data on bubble formation.

In the second task, the scope to the in-tube

condensation investigation wall be measured for

the local condensation heat transfer coefficient

of R22 replacements. This research will be a companion study for last year's NIST study.

Last year our group investigated the local flow

boiling measurements of R22 replacements

(R32/134a, R32/125, and R32/125/134a) in a

micro-fin tube. A designer of new heat pumps

can size both the evaporator and the condenser

with the results of both studies.

Recent Results

Kedzierski, M., Enhancement ofR123 Pool Boiling

by die Addition of N-Hexane, NISTIR5780,

National Institute of Standards and

Technology, March 1996.

Kedzierski, M., Calimetric and Visual

Measurements ofR123 Pool Boiling on Four

Enhanced Surfaces, NISTIR 5732, National

Institute of Standards and Technology,

November 1995.

Kedzierski, M., Effect of Inclination on the

Performance of a Compact Brazed Plate Condenser

and Evaporator, NISTIR 5767, National

Institute of Standards and Technology,

November 1995.

Kedzierski, M., Kim, M.S., Single Phase Heat

Transfer and Pressure Drop Characteristics of an

Integral-Spine-Fin Within an Annulus, NISTIR

5454, National Institute of Standards and

Technology, 1994.

112
FIRE SAFETY ENGINEERING

DIVISION

FIRE MODELING AND

APPLICATIONS
I
Fire Performance Design of HighPerformance Materials Used in

Construction

Principal Investigator

Leonard Y. Cooper

Fire Safety Engineering Division

301-975-6880

Sponsor

National Institute of Standards and Technology

Objective

To develop a special-purpose version of CFAST,

BFRL's Consolidated Fire and Smoke Transport

Model, which focuses on structural analysis

applications involving traditional and high

performance construction materials.

Problem

The standard method of insuring integrity in

fires of building components is based on the

response of building materials to a standardtest-method fire exposure. High performance

steel, concrete, organic matrix composites, and

combinations of these, are being considered for use in many types of modern construction.

Such materials have strength vs. temperature

and failure characteristics that can differ

substantially from those of traditional

construction materials. In additions, these

materials can be used in ways not considered in

the development of codes which dictate their use and thus acceptability. Fires involving

modern furnishings and work environments

may produce exposure conditions that differ

substantially from those simulated by standard

tests. Further, in making the transition to

performance codes for buildings it is crucial that an evaluation tool be developed that supports

the performance methodology, and can do this

evaluation in realistic scenarios. Finally, in

determining the integrity of a particular

candidate assembly in the design process itself,

it will be increasingly important for industry to use modern methods of engineering analysis to assure the cost-effective fire resistance of

buildings.

Approach

During FY 1996, BFRL will evaluate the

performance of buildings and other structures in a fire environment. Three types of phenomena

need to be simulated: 1) the fire environment

and its development; 2) the thermal response

of structural elements exposed to the fire

environment, including loading and non-loading

barriers; and 3) the structural response. The

fire model CFAST, is well recognized as the

leading model for calculating heat transfer

through walls, ceilings, and floors with a 1- dimension analysis that assumes constant

properties, not effected by the fire. To use CFAST in the evaluation of the thermal and

structural response of practical barrier designs,

it is important to improve the analysis of

barrier thermal response by allowing for 2-

dimensionality, where necessary, and for

material properties which change in response to

the fire.

BFRL staff will establish a catalog that includes

a brief list of commonly used barrier designs

and develop and incorporate into CFAST

barrier heat transfer analyses associated with

these designs. The analyses will use measured

material properties and will be validated

experimentally. An advanced version of the

CFAST model will include a thermal response

analysis for general barrier design geometries

and other structural elements, and for

comparison of designs implemented in

traditional and High Performance materials.

The parallel effort will include development of a means of coupling the advanced model to

general structural response models. This will

enhance general acceptance of CFAST in the

international structural design community.

With BFRL's Structures Division staff, they will

determine the most suitable model of structural

systems as a test bed. The emphasis will be on

reliable structural modeling with availability as a research tool. The calculation-based methods

to be developed will be part of the project's

contribution to BFRL's Integrated Knowledge

System for High Performance Construction

Materials and Systems (HPCMS) and will be

distributed electronically to industry and

academia through the HPCMS world-wide-web

server and other means.

115
Recent Results

An alternative ASTM E119 test method

approach that accounts for the actual temperature-dependent structural properties of materials has been studied. Two possible practical

barrier designs for analysis and inclusion in

CFAST have been identified and are working

with PCA, Forintek, and NRC Canada to obtain

experimental data for use in the verifying

predicted fire response of these barrier designs.

One or both will be incorporated into the list of

barriers.

BFS Lite

Principal Investigator

Paul A. Reneke

Fire Safety Engineering Division

301-975-6696

Sponsor

National Institute of Standards and Technology

Objective

To construct a user-friendly version of the

CFAST model (FASTLite) which can be used by

fire protection engineers and fire service

personnel with a minimum of training.

Problem

Fire models have reached a level of

sophistication and reliability that makes them

useful for post fire reconstruction and design

specification. Complex fire models require a fair

amount of expertise and often require a

substantial amount of time and effort in

preparing data. These limits often preclude the use of present models in the field. One means

of moving fire models into common usage is to

increase the usability of the models. A more

usable fire model would need to be fast, userfriendly, reliable and require limited expertise or

training to use. In particular, it would allow a simple method for constructing a realistic fire. As several papers have shown, the fire is the

single most important input for a zone model.

In practice the fire is usually the most difficult

input data to generate. This model could be

used in pre-fire training and planning, and

scenario reconstruction and feasibility studies.

Approach

During FY 1996, BFRL will develop an interface

which uses pictures and reliable databases to

allow the user to build the fire scenario by

selecting burning items based on generic names

and pictures (videos) of these items during

burning. This work is based on BFRL's

Consolidated Fore and Smoke Transport Model

(CFAST), BFRL's core fire model. It has been

extensively verified and is accepted in the legal

community in litigation and adjudication. The

model can be run to determine if a (tentative)

assumed scenario results in the expected (or

116
actual) outcome. An evaluation of the initial

scenario can then be made leading to

appropriate modifications to the scenario. This

method will give confidence in the validity of

the finally developed scenario. The model and

user interface will be provided on CD-ROM and

the data to be used will be made available

through BFRL's WWW Home Page and be

available for downloading to the user's

computer. This should provide a reliable means

to disseminate findings and for the fire

community to avail themselves of the most

recent technology.

Recent Results

New project

Fire Model Evaluation

Principal Investigator

Richard D. Peacock

Fire Safety Engineering Division

301-975-6664

Sponsor

National Institute of Standards and Technology

Objective

To develop protocols to quantify the accuracy

of computer-based predictive fire models and

the experimental, statistical, and analytical

techniques to support this method.

Problem

Users and authorities are often asked to accept

building fire safety design based on fire models

without accepted statements of their predictive

accuracy. Key to the increased use of models in

performance-based standards and elsewhere is the ability to state with confidence how close

actual conditions are to those predicted by the

model. The current state-of-the-art in model

evaluation literature typically consists of

subjective statements such as "good agreement"

or "agrees well." National, through ASTM and

international, through the International Council

of Building Research, Studies, and

Documentation (CIB) consensus on the process

and research needs for model evaluation is evolving from research to date in this project.

The Society of Fire Protection Engineers (SFPE)

also is becoming active in this area.

Approach

During FY 1996, BFRL will address 1)

development of realistic fire descriptions for use

in comparing model predictions wdth

experimental results and 2) cooperation with

other organizations supporting a continuing consensus on procedures for model evaluation,

peer review of models, and sensitivity analysis.

Three tasks are included:

1. Burning characteristics of products. Develop

through real-scale testing, a selected set of

burning characteristics for products which

may become involved in fires. The measured

data must be in a form which can be used by

fire models.

117
2. Continued analysis of complex fire model.

Complete a detailed sensitivity analysis of

the effects of changes in heat release rate on

important calculated outputs for a complex

fire model using BFRL's Consolidated Fire

and Smoke Transport Model (CFAST) to

provide input data for the analysis.

3. Consensus on procedures. Continue effort

to foster international cooperation

(specifically with ASTM, CIB, and ISO) in

fire model evaluation to provide a wellaccepted framework, for future efforts by

NIST and others.

Recent Results

Peacock, R.D., Reneke, P.A., Forney, C.L, and

Kostreva, M.M., "Issues in Evaluation of

Complex Fire Models," submitted to Fire Safety

Journal.

Peacock, R.D., Reneke, P.A., Jones, W.W.,

Bukoswki, R.W., and Babrauskas, V.,

"Concepts for Fire Protection of Passenger Rail

Transportation Vehicles: Past, Present, and

Future," Fire and Materials, Vol. 1 9, 71-87,

1995.

Hazard Version 2

Principal Investigator

Walter W. Jones

Fire Safety Engineering Division

301-975-6887

Sponsor

National Institute of Standards and Technology

Objective

To plan and implement the next generation

hazard methodology.

Problem

Traditional approaches to product design,

product evaluation, and codes and standards

development address fire safety in a piecemeal

fashion - for example, evaluating heat release

without considering product use, toxicity, or

ignition propensity. Quantitative hazard

analysis techniques have the potential of

providing significant cost savings and reducing

the time it takes to bring successful products to

market. In addition, measures are evaluated as an interacting system, including the impact of

both structure and contents. Alternative

protection strategies can be studied within the

hazard analysis framework to give the benefitcost relation for each. Providing these

alternatives promotes the design flexibility

which reduces redundancies and cost without

sacrificing safety.

Approach

During FY 1996, BFRL will assemble the

Hazard methodology package to include

CFAST, BFRL's Consolidated Fire and Smoke

Transport Model, and the new high rise egress

model. The combined effort will be labeled

CFAST/Hazard and will provide the

functionality of both in a graphical user

interface. The primary efforts will address the

production of the software package itself and

supporting a collaborative effort with the Navy

on improving one of the physical phenomena

(longitudinal flow) which is of mutual interest.

The new phenomena which have been

incorporated into CFAST over the past two

years will be documented, the new GUI

paradigm will be explained, the validation effort

118
will be discussed in the writeup (including the

comparison process) and the expanded egress

modeling will be included. Principal Investigator

Glenn P. Forney

Fire Safety Engineering Division

Hybrid Model Development

Recent Results

Completed the Beta test version of CFAST 3.0

and the new user interface.

301-975-2313

Sponsor

Department of Navy

Naval Research Laboratory

Office of Naval Technology

Objective

To develop a model for fire growth and smoke

movement applicable to Navy Ships

Problem

The effect of corridor wddth and relative

pressure on smoke movement is missing from

BFRL's Consolidated Fire and Smoke Transport

Model (CFAST). This will need to be

addressed by examining various CFD concepts.

Approach

CFAST has features that make it attractive for

further development to meet the objectives of

this task. In particular, it has been validated

against a wide range of real-scale experimental

conditions which imbue confidence in its capability. Features which have been added to

address this problem include vertical flow,

mechanical ventilation and compartment to

compartment heat transfer.

Recent Results

Baily, J., and Tatem, P.A., Validation of

Fire/Smoke Spread Model (CFAST) Using Ex-US

S

SHADWELL Internal Ship Conflagration Control

(ISCC) Fire Tests, Naval Research Laboratory,

MR 6180-95-7781, 1996.

119
Implementation of the FDMS

Protocol

Principal Investigator

Paul Reneke

Fire Safety Engineering Division

301-975-6696

Sponsor

National Institute of Standards and Technology

other data sets. This provides for others to build

their own data sets and to forward new data to us for inclusion in future releases.

Recent Results

Portier, Rebecca, W., Peacock, Richard, D., and

Reneke, Paul, A., Fire Data Management System,

FDMS 2.0, Internet Users Guide and Technical

Documentation Addendum, National Institute of

Standards and Technology, (in press)

Objective

To develop a second generation database which

can accommodate all fire related data for users who collect or use building fire data.

Problem

A unified method of accessing data is desirable

to aid both experimental and modeling efforts

in the development of the science of fire. The

Fire Data Management System (FDMS), is a format for organizing and presenting fire data

obtained from bench-scale and real-scale tests and fire simulation programs. By storing

available fire test values in a common format

database, this data is readily available for fire

protection professionals, experimentalists,

building code officials, and others concerned

with the design and construction of "safe"

structures. A central database of test values

generated from a variety of sources within the

fire community needs to be developed.

Approach

During FY 1996, BFRL will provide for three

applications of the database. These include: a

centralized database accessible to users worldwide through a text-oriented interface on

the Internet; a laboratory-dependent

implementation with GUI interface for PC

systems; and a CD-ROM database to be

generated from the centralized database. The

FDMS format database provides an open file design to accommodate future test apparatus

formats. An early version of the Internet

database includes Cone Calorimeter, (ASTM

1354/ISO 5660) and Eurefic Corner Tests (NT

025/ISO 9705) along with several full-scale tests including 3 room, 4 room, and multi-story

structures. The plans for the GUI include the

ability to edit data, and export and import to

120
Study of Heat and Smoke

Movement and Their Influence on

Detector and Sprinkler Response in

Enclosed Spaces with Complex

Ceiling Geometries

Principal Investigator

Richard W. Bukowski

Fire Safety Engineering Division

301-975-6853

Sponsors

National Fire Protection Research Foundation

General Services Administration

Public Buildings Services

Office of Real Property and Management

Federal Emergency Management Agency

U.S. Fire Administration

Objective

To examine the effect of complex ceiling

geometry and obstructions on the distribution

of heat and smoke to optimize requirements for

automatic fire detector location found in NFPA

72E and for automatic sprinklers as covered by

NFPA 13, 13D, and 13R.

Problem

Now, recommendations for the placement of

automatic fire detectors found in the NFPA

Standard on Detection Devices (72E) are based

either on engineering judgement or on limited

experimental data. In the implementation of

these data, tables and curves were developed

from calculations with a zone model which are

also only applicable for flat, unobstructed

ceilings. Since 72E includes recommendations

for placement of fire detectors in spaces with

sloping or peaked ceilings, or with open beams

and joists, some validation of these

recommendations is necessary. Further,

detector siting problems associated with

stratification and high air movement from

HVAC systems are mentioned in the standards,

but only limited installation guidance is provided which are based only on judgement.

Approach

During FY 1996, BFRL will study the effects of

HVAC systems on fire detectors and sprinkler

placement and activation. Work centers on

validating the techniques and results obtained.

In the first two years of this study, research

examined the effects of fire size, fire location,

ceiling height, ceiling slope, typical ceiling

beam/joist configurations and the effect of

stratification on the distribution of heat and

smoke from the fire.

Recent Results

Developed several, novel techniques to conduct

computational experiments in fire flows; results are being assimilated into national standards.

Findings from work on open joists have resulted

in changes to the National Fire Alarm Code.

121
Balanced Design

Principal Investigator

Richard W. Bukowski

Fire Safety Engineering Division

301-975-6853

Sponsors

General Services Administration

Public Buildings Service

Office of Real Property Management and Safety

Federal Emergency Management Agency

U.S. Fire Administration

National Concrete Masonry Association

National Electrical manufacturers Association

Objective

To quantify the operational reliability of

detection, sprinklers, and compartmentation as directed by PI 7 02-522.

Problem

A tradeoff between active and passive fire

protection strategies are often made without

technical foundation. As legislation mandates

sprinklers and detectors in specified occupancies

the role of compartmentation must be

understood so that overall safety is not

compromised. Thus, PL102-522 tasked BFRL

to conduct this study as a joint effort of the

public and private sectors.

Approach

During FY 1996, BFRL will perform three tasks

to meet the objectives of this project:

1. Data Collection. Collect data as background

information to enrich the data base from

hotel and office occupancies and insurance,

government and corporate interests. Work

with industry representatives to identify

other major systems users who might

represent sources of field data.

2. Tradeoffs. Determine the conditions under

which one or more of the systems can be

reduced or eliminated without unacceptable

risk of loss. What "unacceptable" means is

likely to be a highly subjective measure

which needs a public policy type of decision.

3. Fire-Resistive (FR) vs. Noncombustible

Construction (NC). Besides the difference

in fire resistance ratings, field data compiled

in task 1 will be analyzed to identify other

characteristics of these construction types

which impact on their mitigation of risk.

Given that fire resistance requirements are consistent with expected duration negating

any issues about performance differences,

these "reliability" aspects represent the

relevant factors separating these construction

types.

Recent Results

Implemented a general plan to collect and

analyze the data.

122
Enhanced Fire Safety Evaluation

System

Principal Investigator

Richard W. Bukowski

Fire Safety Engineering Division

301-975-6853

Sponsor

General Services Adnrunistration

Public Buildings Service

Office of Real Property Management and Safety

Objective

To advance the technical basis of the Fire

Safety Evaluation System (FSES) and facilitate

its evolution to a risk management tool.

Problem

Current fire safety practice within GSA is rooted in the Life Safety Code prescriptions and

using the FSES for equivalency determinations.

The goal of GSA's Headquarters is to move this

to a risk management basis. Lacking is technical guidance and review^ of fire safety

practices and software development of fire

safety evaluation management tool.

Approach

During FY 1996, BFRL will begin to embed fire

safety evaluation calculations into the FSES in

place of judgmental assignment of scores for

system parameters.

Recent Results

Produce and delivered to GAS a Windows

version of the existing FSES.

Performance Standards

Principal Investigator

Richard W. Bukowski

Fire Safety Engineering Division

301-975-6853

Sponsor

National Institute of Standards and Technology

Objective

To support the application of fire safety

engineering principles that promote the U.S.

transition to Performance Codes and Standards.

Problem

The world is making a major change from

prescriptive to performance codes and

standards. Many recognize the need for the

United States to stay in step wdth these changes

to remain competitive in world markets. This

requires that technological changes associated

with the development and application of Fire

Safety Engineering (FSE) principals need to be

assimilated into the U.S. system.

Approach

During FY 1996, BFRL will continue to support

the transfer of advanced FSE principles into

practice in the United States by working with

codes and standards organizations as a means to

provide the seeds of an educational system for

code officials and continue to work within the

U.S. codes and standards system to facilitate

changes. This work will be started by

introducing a performance-based replacement

for a section of one of the model building codes

based on BFRL modeling and measurement

technology.

Recent Results

Bukowski, Richard, "Setting Performance Code

Objectives," Interflam'96, Interscience

Communications, London, 1996.

Bukowski, Richard, "Performance Codes:

Opportunities and Challenges," National Fire

Academy and NEMA Annual Meeting, National

Electrical Manufacturers Association, 1 995.

Bukowski, Richard, "Fire Codes for Global

123
Prsictice," Progressive Architecture, June 1995. Fire Safe Elevators

Bukowski, Richard, "International Activities for

Establishing Performance Codes," FORUM

Symposium, Tsukuba, Japan, June 1995.

Bukowski, Richard, "Predicting the Fire

Performance of Buildings," ASlAFLAM '95,

March 1995.

Principal Investigator

John H. IClote

Fire Safety Engineering Division

301-975-6890

Sponsor

National Institute of Standards and Technology

Objective

To develop technology allowing the elevators to

be used for fire evacuation of people with

mobility limitations and of the general

population.

Problem

Elevators in use today are not protected against

the effects of fire, and are not intended to be

used for fire evacuation. However, evacuation

by stairs is often not practical for people with

mobility limitations. Fire safe elevators are a

solution to the problem of evacuation of the

disabled, and they also can be used the general

population. Development of elevator fire

evacuation systems requires protective features

and approaches to human issues of evacuees and relevant institutions. Research is not

needed concerning the protective features,

except for protection from water damage due to

sprinklers and fire hoses.

Approach

During FY 1996, BFRLwiU: 1) perform

research on the effects water flow from

sprinklers and fire hoses into elevator shafts,

and 2) work with interested groups to refine the

elevator fire evacuation concept to improve its acceptance. This work is performed as two

tasks:

1. Field tests will be conducted to measure and

visualize water flow in elevator shafts due to

exposures of sprinklers and standing water.

The measurement and visualization

techniques were developed during

experiments conducted last year in its large

fire research facility. Flow visualization will

provide a first look at the water in the shaft

and around elevator cars, and this could lead

to water shielding of sensitive elevator

components.

124
2. Staff will participate in meetings of the

NFPA Means of Egress Committee where a BFRL proposal to allow fire evacuation by

specially protected elevators is being

considered. This participation will be aimed

at assuring that committee discussions on

the topic have the benefit of BFRL's

extensive experience in this area. Refinement of the elevator fire evacuation

concept will also include interaction with the

ASME Task Group on Elevator Use During

Fires and the National Elevator Industry,

Inc. (NEII).

Recent Results

BFRL's findings, submitted as a proposal to

NFPA's Life Safety Code, to allow fire

evacuation by specially protected elevators were

accepted with minor modifications by the

Means of Egress Committee. NFPA will put the

modified proposal out for public comments

during 1996.

A Cooperative Research and Development

Agreement (CRADA) with United Technology

Research Corporation and United Technology's

Otis Elevator studied the concept of the fire

elevator system including system performance

and protection.

Fire Spread in Painted Stairways

Principal Investigator

Henri E. Mitler

Fire Safety Engineering Division

301-975-6886

Sponsor

Federal Emergency Management Agency

U.S. Fire Administration

Objective

To understand and evaluate the problem of

stairwell fires.

Problem

Officials in the New York City Housing

Authority (NYCHA) and also in their Fire

Department (NYCFD) have observed an

increase in the number of fires occurring in

stairwells of buildings under the care of the

NYCHA. Typically, some rubbish, including

discarded furniture, was placed on a landing

and ignited. This produced fires of unusual

severity, which travel rapidly up the stairwell for

many floors, sometimes to the roof bulkhead.

It has been surmised that multiple layers of

paint on the walls supplied a major part of the

fuel and contributed to the spread of flame up

the stairwell. Such fires pose a hazard to life,

and the question is what can be done to

mitigate or prevent them.

Approach

During FY 1996, BFRL will study the fire

spread characteristics of multiple layers of the

paints used by NYC. A mockup will be

constructed to simulate a staircase shaft and

carry out a series of flame spread tests, varying

the painted layers in various ways.

Recent Results

New project

125
Experimental Application of Fire

Hazard Analysis for U.S. Passenger

Train Systems

Principal Investigator

Richard D. Peacock

Fire Safety Engineering Division

301-975-6664

Sponsor

Department of Transportation

Federal Railroad Administration

Volpe Transportation Systems Center

Objective

To demonstrate the practicality and

effectiveness of new generation test methods

and hazard analysis techniques when applied to

passenger rail transportation vehicle fire safety.

Problem

Considerable advances in fire safety engineering

have been made in the decade since the original

development of the current U.S. guidelines for

passenger train material selection. Some

requirements for system design, materials

control, detection, suppression, and emergency

egress are included in the variety of

requirements - with each applying to distinct

subsets of passenger-guided ground

transportation. Better understanding of the

underlying phenomena governing fire initiation

and growth have led to the development of a new generation of test methods that can better

predict the real-scale burning behavior of

materials and assemblies. While, advances in

fire and hazard modeling are leading a

revolution in the analysis of a material's overall

contribution to fire hazards in a particular

application. Such an approach allows

evaluation of factors besides material

flammability, and of tradeoffs in the fire-safe

design of the entire fire safety system. These

advances should be incorporated in future

designs of passenger trains.

Approach

During FY 1996, BFRL will perform full-scale

tests and computer modeling to perform a fire

hazard analysis of a passenger rail vehicle

constructed of currently used materials and

construction techniques. Mockups of passenger

vehicle components will be tested in full-scale to

obtain information for modeling efforts.

Currently available computer-based methods for

fire hazard analysis will be employed to study

specific fire scenarios, including an interior fire,

exterior fire, and an interior fire on a vehicle in a tunnel. At a minimum, the analysis will

consider vehicle design, materials of

construction, detection and suppression

systems, communications systems, and

emergency egress and access. BFRL will consult

with Amtrak to provide input on existing and

planned vehicle designs and configurations.

A technical report will document the hazard

analysis, describe the findings and conclusions

of this analysis, and include explanation of the

relative impact on vehicle fire safety for the

range of overall system design parameters

studied.

Recent Results

Performed bench-scale heat release rate testing

to characteristic material performance in

modern test methods to compare with earlier

generation test methods from the current

guidelines.

Peacock, Richard, D., Bukowski, Richard, W.,

Jones, Walter, W., Reneke, Paul, A., Babrauska,

Vito, and Brown, James, Fire Safety of Passenger

Trains, A Review of Current Approaches and new

Concepts, NIST Technical Note 1406, National

Institute of Standards and Technology, 1994.

126
Fire Research Information Services

(FRIS)

Principal Investigator

Nora H. Jason

Fire Safety Engineering Division

301-975-6862

Sponsor

National Institute of Standards and Technology

Objective

To serve BFRL staff and the broad BFRL user community while serving as a model for

information resource management for the next

century. This resource management system will

be expanded into data dissemination through

FDMS and other protocols.

Problem

To disseminate BFRL documents electronically

to the user community concomitant with

making pertinent information available without

jeopardizing the availability and usability of the

documents.

Approach

During FY 1996, BFRL will continue to provide

electronic access to its documents and software

through the FIREDOC database, FSBBS

bulletin board and BFRL Home Page and will

be investigating methods of capturing

information that will facilitate the creation of a remote access system to full documents. The

Construction Industry Institute (CII)

publications are available from BFRL and new

documents are added as received. Liaison is maintained with ICHIEFS and other database

system managers.

Recent Results

Martin, Phyllis and Jason, Nora, Building and

Fire Research Publications, 1994, NIST SP 838-9,

National Institute of Standards and

Technology, October 1995.

Fire Forum

Principal Investigator

Richard W. Bukowski

Fire Safety Engineering Division

301-975-6853

Sponsor

National Institute of Standards and Technology

Objective

To perform the duties of Secretary to the

FORUM for International Cooperation on Fire

Research.

Problem

The FORUM is an international body of the

Heads of fire research organizations around the

world, chaired by BFRL. Sixteen members

representing 14 countries participate; several

new members are expected before the next

annual meeting. The group requires the

technical support of a trained professional to

perform the day-to-day activities required to ensure effective international cooperation.

Approach

During FY 1996, BFRL will produce a meeting

report for internal distribution and an annual

report for general distribution. The Secretary

also will disseminate information on the

FORUM and its activities to appropriate

organizations and to the public through

INTERNET and printed media. The Secretary

will assure that assignments made at the annual

meeting are completed on schedule.

Recent Results

Bukowski, Richard, W, Ed., 1995 Annual

Meeting Notes, Forum for International

Cooperation on Fire Research, 1995.

127
Computing and Network Resources

Principal Investigator

James W. Raines

Fire Safety Engineering Division

301-975-6855

Sponsor

National Institute of Standards and Technology

Objective

To provide improvements, day-to-day support

and long range planning for the BFRL network,

and associated computing environment.

Problem

Efficient computing requires a uniform and

consistent environment for both scientific and

administrative services. As science and

engineering evolve toward more collaborative

efforts, a faster and more robust local area network is essential.

Approach

During FY 1996, BFRL will continue to provide

the best network system possible, including,

speed, reliability and compatibility. The thrust

will be to obtain and maintain the fastest and

most reliable LAN system consistent with ease

of use and minimum disruption. Work centers

on configuring, purchasing and installing new

hardware and operating software for the local area networks to provide a uniform and

consistent system. LAN system hardware and

software will be upgraded, and connection to

the new fiber-optic backbone hub concentrators

will provide a means for high speed (100 mbs)

access to high end workstations.

Recent Results

Increased the throughput of LAN and shared

resources; downtime has been kept to a rrunimum; started installing the planned

evolution to the high speed (100 mbs) network;

and provided increased emphasis on general

network and computer related help for those

who needed and/or requested it.

128
RECENT GRANTS - FIRE

MODELING AND

APPLICATIONS

1 . Interactive Virtual Environments

for Fire Simulation

Principal Investigator

Carlos H. Sequin, Ph.D.

Computer Science Division, EECS Department

University of California, Berkeley

Sponsor

National Institute of Standards and Technology

Objective

To combine Berkeley virtual reality

architectural walk-through technology with

NIST CFAST fire simulation technology,

providing simulation and scientific visualization

of the CFAST model within a real-time,

interactive virtual environment.

Problem

Virtual reality techniques developed at Berkeley

over the last 5 years provide intuitive, real-time

visualization and interaction with conditions

and structures in heavily occluded architectural

environments. NIST's CFAST fire simulation

software provides fast, accurate computation of

conditions within buildings in fire situations,

but lacks the ability to construct simulation

scenarios interactively or directly to visualize

results in 3D. A marriage of these technologies

will bring interactive 3D visualization to fire

simulation. This will provide immediate

benefits in translating real-life scenarios into

computer models, and converting the results of

those computer models into easily understood

visualizations of simulation conditions. In the

longer term, this combination of technologies

has great potential in firefighter training and

performance-based standards for building

design.

Approach

In the first year, FY 1995, emphasis was on

bringing CFAST and WALKTHRU together so CFAST could run a simulation while basic

elements such as fire size and interface height

were visualized in the WALKTHRU

environment. Although the two systems

operate on conceptually similar models of the

world (i.e., a "cell-and-portal"structure), the

specifics of the implementations are sufficiently

different that efforts for the first few years will

involve running the two programs on parallel,

but separate world models. WALKTHRU

provides the front end for interaction with and

visualization of the virtual world, and CFAST

provides the engine by which environmental

conditions in the virtual world are updated.

Presently, an integrated system is working in

which CFAST and WALKTHRU work

side-by-side, on a pair of models which are input separately. This procedure involves, one

CFAST model contains the fire scenario, one

WALKTHRU model contains the detailed

world geometry, and a "registration map" which

allow the two programs to relate their models of

the world. Most of the FY 1995 and FY 1996

work involves the creation of the simulation

models. The world geometry required by

CFAST is a subset of the viewing geometry

required by the WALKTHRU, so it is possible

to automate or help the user in creating CFAST

geometry from a WALKTHRU model. 3D

model generation is a difficult and insufficiently

studied task; a large part of our research

contribution will be to develop techniques by

which usable 3D models of interesting

environments can be generated either by hand,

interactively, and/or by automated processing of

CAD floor plan information. This work will

allow rapid and accurate creation of the

environmental geometry which is needed for

any simulation or visualization to take place.

Recent results include the Building Model

Generator (BMC), which automatically

generates a WALKTHRU model and its corresponding registration map from an AutoCAD floor plan. BMG corrects common

modeling errors and generates a complete 3D

model with little or no human intervention,

reducing the time required to model a building

by two to three orders of magnitude. The

second major thrust involves generating and

modifying fire simulation scenarios interactively

from within the virtual environment, and

visualizing the results of the simulation

intuitively and interactively in the virtual

environment. It is intended to set a fire by

129
walking into a room within the WALKTHRU

and select a wastebasket or chair to begin

burning, rather than juggling numbers and

codes in a text file. Furthermore, using the

WALKTHRU environment, one can visualize

quantities such as interface heights, temperature

distributions, and species concentrations

spatially in real-time, rather than as two-dimensional plots. Work is currentlyunderway on creating a user interface to set the

simulation parameters from within the 3D

virtual environment (location of the fire,

environmental conditions during the

simulation, and so on). The FY 1995 work

resulted in the ability to take a normal CFAST

fire scenario and visualize the fire size, plume,

and interface heights within the environment in

real time. This work continues into FY 1996.

Techniques for visualizing the other spatial

quantities that result from the simulation in the

3D environment will be developed. Once these

techniques are developed, the user will be able

quickly and easily to create a complete, highly

accurate geometric model of an architectural

environment. From within the model, they can

set up simulations interactively, and watch the

results unfold spatially and intuitively in real

time.

Recent Results

Lewis, Richard W., Generating Tliree-Dimensional

Building Models from Two-Dimensional Architectural

Plans, Masters' Thesis, University of California,

Berkeley, Berkeley, CA, in press.

2. Enhanced PC-based Building Fire

Assessment System

Principal Investigator

Edward IC Budnick, P.E. Hughes Associates, Inc. 410-737-8677

Sponsors

National Institute of Standards and Technology

U.S. General Services Administrative

Public Building Services

Office of Real Property Management

Objective

To develop a PC-based version of the current

Fire Safety Evaluation System for office

occupancies and integrate selected quantitative

methods that will enable engineers to perform

detailed fire hazard, risk equivalency, and cost

optimization analyses for existing or planned

buildings.

Problem

The need to accurately measure fire risk impact

and estimate costs of different fire safety

strategies on levels of fire safety in individual

buildings is essential to achievement of an

overall building risk management philosophy.

Limitations in current prescriptive requirements

represent significant inhibitions to needed

design flexibility and general usefulness. There

is a growing need among building owners, local

code authorities and design engineers about the

availability of quantitative methods to evaluate

building fire safety within a broad, risk-based

context which permits examination of

"equivalent" alternatives.

Approach

This effort is being conducted in three phases.

Phase I was completed in FY 1995 and involved

development of a PC-based version of the

NFPA-FSES for business occupancies. This

program was developed using the Microsoft

Visual C/C +-f- Windows development platform

and is fully compatible with the normal

Windows environment. It contains explanatory

text to assist the user in selecting the correct

parameter conditions and uses visual prompts

130
to gtiide the user through the FSES method.

The progranr\ contains four modules of

encapsulated code, each with specific tasks.

The Applications Module is the main program.

This module controls the individual

performance elements, including calculations,

output, and interface parameters.

The Main Window Module is the outer

framework of the Windows-based program. It

is analogous to the Program Manager in

Microsoft Windows and allows the user access to file input/output features, print features,

window controls, and program help.

The Document Module is the storage medium

for user input. This module is invisible to the

user. The document module contains all of the

scoring functions, filters that check if data are complete and accurate, and all of the code for

storing data to a file.

The View Module is the interface, used for

entering data and selecting score categories.

Currently, there are 15 elements in the View

Module. The current version of the program

has been validated on a limited basis against the

FSES method in NFPA 101 A and can be used

as an interim method for conducting FSES

evaluations in office buildings.

Phase II was started in FY 1996 (completed in

FY 1997) and is directed at the research to

enhance the methodology to allow quantitative

comparison of design options. This includes

integration of appropriate elements of currently

available engineering calculations (e.g.. Hazard,

FPETOOL, etc.) and development of algorithms

to assess reliability.

Phase III will attempt to integrate the results

and methods developed in the initial phases

into a computerized risk management program.

Recent Results

(Cite Author(s)), Fire Safety Evaluation System

(FSES)for Business Occupancies Software (Version

1.0for Windows®) User's Manual, NIST-GCR96-692, National Institute of Standards and

Technology, March 1996.

3. Accelerating the Application of

Advanced Fire Safety Design

Methods in the United States

Principal Investigator

DavidA. Lucht, P.E.

Professor and Director

Center for Fire Safety Studies

Worcester Polytechnic Institute

508-831-5593

Sponsor

National Institute of Standards and Technology

Objective

To accelerate the flow of modern fire protection

engineering calculation methods into day-to-day

practice. To increase knowledge and

understanding of advanced fire safety design

methods through development of education al packages targeted to fire safety design

professionals and regulatory authorities.

Problem

Research of the past three decades is bearing

fruit as new approaches to predicting fire

performance through advanced calculation

methods. For a host of reasons, many of these

calculation methods are not yet enjoying

widespread use among fire safety design

professionals and regulatory authorities. One

barrier to increase use is simply a lack of

knowledge.

Approach

The initial effort focused on a calculation

method that has become well established

through peer review and consensus within the

professional engineering community. The

American Society of Civil Engineers (ASCE)

Calculation Method for Structural Design for

Fire Conditions has been selected for this initial

effort. This methodology is in the final stages

of being processed through the ASCE consensus

process under ANSI protocol. The ASCE

Committee on Special Design Issues: Fire

Protection is in the process of preparing a

design manual for this new ASCE document.

Work is closely coordinated with this ASCE

committee in the development of the manual

and an accompanying educational package.

131
During this first year the first draft of the

manual will be completed, the target audience

will be defined and specifications for the

educational package will be completed. Initial

progress has been delayed pending outcomes

from the ASCE consensus process but work is moving forward in defining the audience and

outlining the educational package.

Recent Results

New project

4. Evaluation of Alternative

Methods for Fire Rating Structural

Elements

Principal Investigator

Robert Dexter, Ph.D.

Senior Research Engineer

Center for Advanced Technology for Large

Structural Systems

Lehigh University

610-758-6108

Sponsor

National Institute of Standards and Technology

Objective

The objective is to evaluate current

computational methods for the assessing the

integrity of structures exposed to fire and to

develop practical tools for analysis in support of

economical fire-safe construction.

Problem

The current U.S. Standard is ASTM El 19, but

this document has several disadvantages. ASTM

E1I9 allows for two rating options, furnace

testing with a simultaneous load, and, furnace

testing without a simultaneous load. The

United States does not have furnace test

facilities capable of carrying out a column

furnace test under load. Consequently, all ASTM El 19 column ratings determined in the

United States follow the no-load option.

Because of the inherently greater conservatism

of the limiting-temperature criteria, ratings for

the same section which redetermined from

testing under load are expected to be somewhat

larger than those determined by the

limiting-temperature criteria in the no-load

furnace tests. For a variety of reasons,

structural elements in buildings are not usually

loaded to anywhere near their maximum

allowable limits. However, despite the expected

level to which individual elements are actually

loaded, present building codes would typically

require like structural elements to have the

same ASTM El 19 rating. The structural

responses of the individual elements are dependent on their end constraints, which: 1) are strongly coupled to the response of the

overall structure; and, 2) can have major impact

132
on element load-bearing capability. Clearly,

computational thermal and structural analyses can provide a means of addressing and resolving

these issues.

Approach

The approach is to evaluate computational

methods for advancing accepted U.S. methods

of evaluating the fire performance of structures.

This 2-year level of effort will review the range

of possible approaches, from simple calculations

to sophisticated numerical simulation, and gain

competence with and apply at least one

computer program. As for numerical

simulations, it is planned to acquire and install

at ATLAS, the specialized computer program

SAFIR, developed by J-M. Franssen of the

University of Leige, for simulating the thermal

and structural response of fire-exposed

structures. Dr. Franssen will train the principal

investigator and a graduate research assistant

and provide support for SAFIR. In addition,

the capabilities and shortcomings of using more

widely available and user-friendly computer

programs such as ABAQUS will also be

evaluated. Initial applications of SAFIR will

involve simulating the response of structural

elements as they are subjected to ASTM El 19

furnace fire tests. This study will include

simulations of loaded columns and/or composite

floors label elements, previously tested under

furnace conditions, and comparisons between

computed and measured results. The objective

of the initial SAFIR effort is to study the

feasibility of using a computational approach to

determine ASTM Ell 9 ratings as a possible

alternative to full furnace testing. Here,

feasibility includes consideration of the practical

issues of 1) instilling confidence in the U.S.

building-code-making and -using community

that a calculation-based ASTM El 19-type

method of determining fire resistance is a

reliable alternative to the recognized ASTM

El 19 furnace test method, and 2) developing a

plan on how to develop such an alternative to

the point that it is recognized and adopted. At

the conclusion of this 2-year program, the scope

of the work, necessary to complete the

development of an advanced, calculation-based,

fire-resistance rating system for use in United

States building codes will be clearly defined.

This future work will include consideration of:

1) the expanded use of thermal and structural

analysis simulations to include evaluation of the

fire performance of structural elements to fire

environments other than the ASTM El 19

standard fire, i.e., to real fire environments; and,

2) evaluation of the fire performance of entire

structures, e.g., steel-framed buildings with

composite floor slabs, first when exposed to the

standard fire environment, and then to real fire

environments.

Recent Results

New project

133
5. Computational Heat Conduction

for Zone Fire Modeling

Principal Investigator

William F. Moss

Department of Mathematical Sciences

Clemson University

864-656-5225

Sponsor

National Institute of Standards and Technology

Objective

To develop, implement, and test a set of 1-D

and 2-D heat conduction models suitable for

incorporation into the NIST zone fire model

CFAST. To develop the data structures

necessary to code the transfer of heat between

rooms through ceilings, floors, and walls. To

develop a prototype zone fire model written in

Fortran 90. Problem Implement the transfer of

heat between adjoining rooms of a building in a zone fire model. Determine if vertical heat

transfer in walls is significant by comparison of

1 and 2-D models.

Problem

In the NIST zone fire model CFAST, the four

walls of the typical room are lumped together

and divided into upper and lower sections by

the smoke layer interface. A 1-D submodel for

heat conduction into the upper and lower walls

is implemented, but heat is not transferred

between rooms. The radiation submodel used in

CFAST computes configuration factors for the

upper and lower walls which are functions of

time because of the movement of the smoke

layer interface.

Approach

Work performed resulted in the following

recommendations. 1 . It is recommended that

future versions of CFAST be written in Fortran

90. 2. Experimentation shows that the method

used in CFAST of computing heat transfer

through upper and lower walls to the outside is adequate. The finite difference method used in

CFAST is a good choice .3. Experimentation

indicates that the implicit, alternating direction

method of Peaceman and Rachford (PR

method) is a good choice for modeling 2-D heat

conduction in walls. If the PR sweep in the

y-direction is turned off, we have the PR x-only

method which solves a set of 1 -D heat

conduction problems through the wall to

approximate the 2-D wall temperature profile.

Using a simple logical switch, the PR method

can be converted to the PR x-only method soon

subroutine can handle both models. The PR

method is very efficient. The operation count is cut in half by switching to the PR x-only

method. For thin walls, experimentation shows

that there is no apparent difference between the

outputs of the PR method and the PR x-only

method. The PR x-only method can be used for

thin walls. Being able to switch to the PR

method, for thicker walls is an important

feature of this approach. The current method of

computing configuration factors for upper and

lower wall surfaces that change with time is not

computationally efficient. Also, the

configiiration factors associated with upper

walls are indeterminate when the layer height is at the ceiling. A better approach would be to

divide the wall into horizontal strips of equal

height and then to compute and store

configuration factors for all rooms before the

simulation begins. In creating a simple radiation

code of this type, the author gained an

appreciation for the difficulties of this task.

Radiation modeling is both programming

intensive and computationally intensive. If a

radiation model does not conserve energy,

especially at low fire power, the simulation can be adversely affected with respect to both

accuracy and run time. The

differential-algebraic equation solver used in the

simulation can be thought of as a mass and

energy conservation engine that adjusts the

solution variables at each time step by an

iterative procedure so that mass and energy are conserved. Radiation models, especially poor

ones, lead to slow convergence of the iterative

method and increased computation times.

Recent Results

Moss, W.F., Computational Heat Transferfor Zone

Fire Modeling, Final Report: NIST Grant No.

60NANB2D1281, Covering the Period June 1. 1994 to March 31, 1996, Clemson University,

1996.

134
6. Flow Through Vents in a

Compartment Fire

Principal Investigator

Yogesh Jaluria

Department of Mechanical and Aerospace

Engineering

Rutgers - The State University of New Jersey

908-445-3652

Sponsor

National Institute of Standards and Technology

Objective

To carry out a detailed experimental study on

the flow of smoke and hot gases in open vertical

shafts, such as elevator shafts, focusing on the

effects of ventilation, aspect ratio and operating

conditions.

Problem

The flow in open vertical shafts is important to

accurately model fire-induced flows in

multi-leveled buildings since a considerable

amount of transport of the combustion

products occurs due to the shaft. The

importance of the flow in vertical shafts has

been demonstrated clearly in several recent fires

in tall buildings, where the spread of the fire

was strongly influenced by the presence of the

shaft. Therefore, this transport mechanism must

be included in the model for predicting the

spread of smoke, hot gases and other

combustion products, particularly toxic

ingredients, at different levels in the building.

Vertical shafts with large height to width ratio are of particular relevance to typical

multi-storied buildings. In most cases, some

form of ventilation, including forced ventilation,

exists in these shafts. Forced ventilation may

also be used to reduce the spread of toxicants in

the building, allowing greater time for

evacuation of the building.

Approach

An experimental system has been designed and

fabricated for study of the flow in two different

shafts, of height to width ratio (aspect ratio) of

3 and 10. Heated air is injected into the shaft at a lower opening and the downstream flow and

temperature field are monitored by means of

hot-wire anemometers and thermocouples.

Visualization with injected smoke is also used

for a qualitative view of the entire flow field.

The conditions at the outlet are measured to

determine the effects of entrainment into the

flow, heat transfer to the walls and ventilation.

Wide ranges of the physical variables in the

problem are considered so that typical flows due

to fire in multi-leveled buildings with vertical

open shafts can be simulated. For the smaller

aspect ratio shaft, the operating conditions were

varied so that the transport processes range

from high buoyancy levels, for which the

entering flow was found to stay close to the

vertical wall of the shaft, to much lower levels,

for which the flow was found to spread outward

with substantial entrainment and consequent

dilution. With increasing inlet temperature, the

buoyancy effect is increased, resulting in higher

vertical velocities and shorter time to reach the

top opening, as measured by optical monitoring

of smoke. The time taken by the flow for

traversing the distance between the two

openings is an important quantity since it indicates the speed with which smoke and other

combustion products reach into the higher

levels of the building. The effect of the inlet

flow rate is found to be relatively small, with a

larger flow rate resulting in shorter time. The

temperature at the outlet depends on heat

transfer to the walls as well as on the flow

velocity. These two effects oppose each other

and the resulting ratio of the outlet temperature

difference to the inlet temperature difference

does not show a monotonic variation with an

increase in inlet temperature. Detailed

measurements on the velocity and temperature

fields have also been taken. The different flow

regimes that arise as the shaft aspect ratio,

ventilation, and inlet conditions are varied are

investigated. The results obtained on the

unvented small aspect ratio shaft indicate that

the velocity and the temperature are horizontally nonuniform in the shaft. A wall

plume is generated which conveys the hot fluid

rapidly along the shaft wall from the inlet to the

outlet. A slow moving recirculating flow arises

away from this wall, with this flow affecting the

heat transfer and flow in the wall plume. This

also affects the entrainment into the flow, decay

of the temperature field and rate of downstream

movement. Therefore, horizontal uniformity

135
can not be assumed in this case.

The wall plume has to be modeled, considering

the entrainment into this boundary layer flow

and the interaction with the recirculating flow.

The flow was found to rise to the closed top and

generate a stratified region, eventually flowing

out of the upper opening. When the side vent is opened, the entrainment was found to increase

slightly. However, the mixing near the inlet

increased substantially. This results in a lowering of the temperature level in the shaft.

The effect of opening the top of the shaft had a much more substantial effect on the flow and

heat transfer in the shaft. Very little flow was

found to emerge from the top opening, as expected, and the temperature levels were found

to be much lower and the velocity levels to be

much higher. A detailed experimental study of

the flow in the large aspect ratio vertical shaft

(aspect ratio of 10) with and without

ventilation has also been carried out. Again,

wide ranges of the inlet temperature and flow

rate were considered.

The discharge velocity of the hot gases or smoke

was generally kept small to simulate the typical

circumstance in building fires. The

measurements included mass flow rates at the

inlet and outlet channels, downstream decay of

the temperature level, rate of smoke movement,

and temperature and velocity fields in the shaft.

It was found that the temperature distribution

is fairly uniform across a horizontal plane in the

shaft, making it possible to develop a simpler

one-dimensional model. Thus, the flow is fairly

well mixed as it moves downstream and the wall

plume-recirculating flow structure is not

observed. The effects of ventilation by opening

the side vent or the shaft top were similar to

those observed earlier. The results obtained

were also compared with those from the first part of the study on small aspect ratio shafts.

All the results are obtained in dimensionless

terms to facilitate their use in the modeling of

building fire situations. The ranges of the

governing parameters are chosen to cover

typical fires in multi-leveled buildings.

This effort is expected to lead to a better

understanding of the flow in vertical shafts and

to yield quantitative inputs which may be used

for modeling fires in multi-leveled buildings.

The important physical aspects to be

investigated include ambient fluid entrainment,

dilution, speed of smoke spread and effects of

forced ventilation.

Recent Results

Kapoor, IC and Jaluria, Y., "Flow and Heat

Transfer Due to a Buoyant Ceiling Jet Turning

Downward at a Corner," ASME J. Heat Transfer,

Vol. 118, pp. 38-46, 1996.

Mercier, CP., Fire-Induced Flow of Smoke and Hot

Gases in Vertical Shafts, M.S. Thesis, Rutgers

Univ., New Brunswick, NJ, Jan. 1996.

Jaluria, Y., Chiu, W.ICS. and Lee, S.H.-IC,

"Flow of Smoke and Hot Gases Across

Horizontal Vents in Room Fires," Combust. Sci.

Tech., Vol 110-1 11, pp. 197-208, 1995.

G.P. Mercier and Jaluria, Y., "Fire-Induced Flow

of Smoke and Hot Gases in Open Vertical

Shafts," Symp. Thermal Sci. Engg., Berkeley, CA,

pp. 261-268, 1995.

Abib, A. and Jaluria, Y., "Turbulent Penetrative

and Recirculating Flow in a Compartment Fire,"

ASME J. Heat Transfer, Vol. 1 1 7, pp. 927-935,

1995.

136
7. Flows in Vertical Shafts

Principal Investigator

Edward E. Zukoski

California Institute of Technology

818-395-4785

Sponsor

National Institute of Standards and Technology

Objective

To provide the information required for the

development of computer-based models for

flows in vertical shafts and passages during a

fire within a building.

Problem

The research program in progress at Caltech

involves the development of a description of

transient flow of buoyant gas in a vertical shaft.

Flows of this type are a primary means of

transport of hot, toxic gas through a multistoried structure and the description of this

process is not yet available for use in computerbased fire codes. Examples are the flow of hot

gas up ventilation and elevator shafts or

stairwells when the stack effect is absent or weak.

Approach

The basic study involves an investigation of the

flow in a vertical shaft filled with cool air before

the start of the experiment and has walls that

are at room temperature. A typical experiment

starts when the bottom of the shaft is suddenly

opened and exposed to a large reservoir filled

with hot toxic gas. A turbulent mixing process is produced because high density air is placed

above the lower density hot gas. The

subsequent penetration of the hot gas and toxic

species into the shaft by means of the turbulent

mixing process and the better known stack

effect is the subject of this study. _

Experiments are being carried out in a shaft that

is 0.25 m square and 2.4 m high. The shaft is open at the bottom and the walls, composed of

2.5 cm thick aluminum plates, remain close to

room temperature during a typical experiment.

Heat transfer to the walls of the shaft affects

both the stack and turbulent mixing processes.

The effect on the shaft flows of openings at

various positions is also being investigated

under conditions in which both processes are important.

This investigation is an ongoing program that

will take several years to complete. Initial

studies of the temperature field and heat

transfer in a closed shaft due to the turbulent

mixing process have been completed, and

studies of the motion of toxic species in the

shaft and flows in which both stack and

turbulent mixing processes are important have

begun.

Recent Results

Initial results show that the long time-averaged

spatial distribution of temperature and wall

heat transfer rates reach a steady state

immediately after the hot gas first reaches the

top of the shaft and that the presence of heat

transfer has a dramatic impact on the density

distribution in the shaft.

137

FIRE SAFETY ENGINEERING

DIVISION

LARGE FIRE RESEARCH

Fire Flows

Principal Investigator

Howard R. Baum

Fire Safety Engineering Division

301-975-6668

Sponsor

National Institute of Standards and Technology

Objective

To develop a fundamental understanding of the

mechanisms, which control the generation and

transport of heat and smoke in fires and to

develop a predictive capability that will allow

the computer simulation of fires associated with

constructed facilities to be based on the

underlying physical principles.

Problem

The interaction of fires with the physical

environment in commercial, industrial,

residential, and transportation facilities has

been a major research topic for BFRL and its international counterparts since its inception.

The dominant problem of heat and smoke

movement in these facilities is of interest to

their builders, owners, operators, regulators, and

insurers. Small scale combustion processes are the study of diffusion flames in a turbulent flow

environment and as such are of interest to the

general combustion community. Simulations

performed to date have helped the

petrochemical industries, the State of Alaska,

and the U.S. Minerals Management Service.

Approach

During FY 1996, BFRL will continue to perform

detailed studies of individual phenomena of

transport, mixing, diffusion, radiation, and

reaction processes occurring at widely different

length and time scales. Theoretical and

computational techniques applied to the study

of these phenomena are carried out in a way

that permits them to be assessed individually

and later combined into overall simulations of

problems of interest.

Recent Results

McGrattan, ICB., Baum, H.R., and Rehm, R.G.,

"Numerical Simulations of Smoke Plumes from

Large Oil Ylres," Atmospheric Environment, Vol. 6,

(In press), 1996.

Baum, H.R., McGrattan, ICB., and Rehm, R.G.,

"Large Eddy Simulations of Smoke Movement

in Three Dimensions," Conference proceedings

of the Seventh International Interflam

Conference, Interscience Communications, London

pp. 189-198, 1996.

Baum, H.R., McGrattan, ICB., and Rehm, R.G.,

"Simulation of Smoke Plums from Large Pool

Fires," 25th Symposium on Combustion, The

Combustion Institute, Pittsburgh, PA, pp. 1463-

1469, 1994.

141
Large Eddy Simulation (LES)

Verification

Principal Investigator

Kevin McGrattan

Fire Safety Engineering Division

301-975-2712

Sponsor

National Institute of Standards and Technology

Objective

To verify the LES field model applied to the

prediction of ceiling temperatures and

sprinkler/draft curtain interactions.

Problem

The high resolution potential of the LES field

model has been difficult to verify, especially

when applied to large spaces and complicated

flow patterns such as those introduced by

automatic sprinklers. Current measurement

technologies are limited by spatial resolution

and advanced measurement techniques are generally limited to laboratory scale

experiments. Despite the limitations,

verification is a critical aspect to the

development and acceptance of the LES model.

Approach

During FY 1996, BFRL will compare LES

predictions with the results of experiments

conducted at FMRC which addressed the issue

of sprinklers and draft curtains. Funding for

large scale experiments will be sought from the

NFPA Research Foundation. Hot nontoxic

smoke has been used in several countries to

conduct acceptance tests for smoke control

systems. This technique will be examined to

determine its applicability to LES verification.

Infrared thermography will be used to obtain

verification data. An infrared thermography

system will determine the temperature of the

walls or ceiling in a fire compartment. An

infrared camera will be used to measure the

temperature of the unexposed side of a thin

metal ceiling in a small scale experiment. The

measurements will be compared with the

predictions of the LES model including new

capabilities for heat transfer being developed in

the Fire Flows project. Although the infrared

measurements will not precisely be the wall

temperatures, they can be used to determine the

relative temperature field over a large area. The

results of the small scale experiments, will be

used to evaluate the potential for using this

technique in larger experiments or small scale

experiments with complex ceiling structures.

Sprinkler hardware from tests conducted by

FMRC was characterized for fiow and air

entrainment in tests carried out in an aircraft

hanger in Richmond, VA. The measurements

have been used to create a realistic simulation

of the sprinkler spray for use in the LES model.

Recent Results

New project

142
Smoke Plume Trajectory From in

situ Burning of Crude Oil in Alaska

-- Phase II

Principal Investigator

Kevin McGrattan

Fire Safety Engineering Division

301-975-2712

Sponsors

Alaska Department of Environmental

Conservation

Division of Spill Prevention and Response

Environmental Management Consultants,

Alaska, Inc.

Objective

To provide information about the expected

trajectory of smoke plumes from the use of in

situ burning as a response method for oil spills

in Alaska.

Problem

There is need to determine the downwind

concentrations of smoke particulate from the in

situ burning of oil on water with emphasis on

multiple burns and on complex terrains of

Alaska.

Approach

During FY 1996, BFRL will extend the

application of the LES model of a smoke plume

trajectory to account for multiple burns and

complex terrain. Specific areas of concern in

Alaska will be used for simulations. In addition,

BFRL will provide technical support to

EMCON in its bid to secure EPA approval for

the application of the LES model to Alaska.

BFRL also will install, in Alaska, a version of the

LES model to be used by EMCON and ADEC

personnel.

Recent Results

McGrattan, ICB., Walton, W., Putorti, A.D.,

Twalley, W.H., McElroy, J., and Evans, D.D.,

Smoke Plume Trajectoryfrom In-Situ Burning of

Crude Oil in Alaska, NISTIR 5764, National

Institute of Standards and Technology,

November 1995.

In-situ Burning of Oil Spills

Principal Investigator

William D. Walton

Fire Safety Engineering Division

301-975-6872

Sponsor

Department of the Interior

Minerals Management Service

Technology Assessment and Research Branch

Objective

To determine conditions where in-situ burning

can be used effectively as a response method to

accidental spills of crude oil on land and on

water.

Problem

In support of other agency objectives to carry

out burning as a response method to oil spills,

predictions are needed to assess the impact of

the smoke plume produced by burning on

downwind locations. BFRL's Large Eddy

Simulation (LES) model continues to gain

acceptance for use in planning in-situ burns

although there has been limited verification.

There is a need for predictions that take into

account the effect of local terrain features such

as mountains. Further, the spill response

planning community has shown a strong

interest in using the LES model as a planning

tool.

One of the most significant remaining obstacles

to the acceptance of burning as a spill response

technique is the lack of a standard method for

evaluating a fire resistant oil spill containment

boom. To develop a test method, knowledge of

the thermal exposure conditions and physical

stresses that the boom is expected to be exposed

to, must be determined.

Approach

During FY 1996, BFRL will continue to verify

its LES model using the LIDAR smoke plume

data collected by SRI but not yet available in

final form. Using the University of Oklahoma's

Advanced Region Prediction System, local

terrain effects will be added to the model. The

feasibility of developing a PC version of the LES

143
model will be examined, and if practical, a PC

version developed.

To fully characterize the thermal exposure

conditions on a fire resistant boom, a series of

experiments will be performed to measure the

exposure of the boom during a characteristic

spill fire. These burns will examine the effect

of spill size and fuel type. If a reduced smoke

fuel or burning arrangement can be found which

produces the same thermal exposure as a real

spill, then one the obstacles to conducting

future experiments at facilities such as OHMSETT would be elirrunated.

Recent Results

McGrattan, KB., Walton, W., Putorti, A.D.,

Twilley, W.H., McElroy, }., and Evans, D.D.,

"Smoke Plume Trajectory from In-Situ Burning

of Crude Oil in Alaska - Field Experiments,"

Proceedings of the 18th Arctic and Marine Oil Spill

Program (AMOP) Technical Seminar,

Edmonton, Alberta, 14-16 June 1995, pp. 901-

913, 1995.

Walton, W., Twilley, W.H., Putorti, A.D., and

Hiltabrand, R.R., "Smoke Measurements Using

and Advanced Helicopter Transported Sampling

Package with Radio Telemetry," Proceedings of

the 18th Arctic and Marine Oil Spill Program

(AMOP) Technical Serrunar, Edmonton,

Alberta, 14-16 June 1995, pp. 1053-1074,

1995.

Demonstration of Water-Based Fire

Fighting Agents

Principal Investigator

Daniel Madrzykowski

Fire Safety Engineering Division

301-975-6677

Sponsor

Federal Emergency Management Agency

U.S. Fire Administration

Objective

To develop methods for demonstrating

biodegradable, environmentally safe, nontoxic

fire suppression liquids which are effective on

Class A, B and many D fires.

Problem

Water-based fire fighting agents have been used

for many years to enhance the fire fighting

capabilities of ordinary water. The most widely

used of the water-based agents are the foams for use on Class B fires. Agents designed primarily

for Class A fires were used extensively with

wildland fires. More recently, these agents were

promoted for use on a wider range of Class A

and sometimes Class B and D fires. These

agents are frequently advertised as more

effective than plain water while being

environmentally safe. Sometimes they also are claimed to reduce the quantity and toxicity of

smoke.

There are several commercially available waterbased fire suppression agents designed primarily

for Class A fires. Generically these agents can be classified as surfactants which reduce the

surface tension of water, potentially modifying

the fire fighting capabilities. There are standards for assessing these agents, however

most of the criteria do not address the fire

fighting (protection/suppression) capabilities of

the agent. This is particularly true for Class A

and Class D fires. An evaluation protocol is needed to measure the fire fighting capability of an agent and to relate its performance to plain

water or another agent in a given situation.

This would enable the fire protection

community to select the most cost effective fire suppression agent(s) to fit their specific needs,

144
thus optimizing use of their resources.

The use of water-based fire fighting agents raises

the question of potential health and

environmental effects. First is the exposure of

fire fighters to the agent itself and the products

of combustion produced when using the agent.

Second is the impact as agent run off enters the

environment. These issues have generally been

addressed with standard toxicity and

environmental impact tests, although a complete series of these tests has not been

performed even for the most commonly used

agents.

Approach

During FY 1996, BFRL will perform three tasks:

1. Collect information on agents which are considered by their manufacturer to be

biodegradable, environmentally safe,

nontoxic fire suppression liquids which are

effective on Class A, B and many D class.

2. Develop methods and assess the

biodegradability, environmental safety,

toxicity and physical properties of some

water-based fire fighting agents.

3. Develop methods and demonstrate the fire

fighting effectiveness of several water-based

fire fighting agents for Class A, B and D

fires. Recent Results

New project

Demonstration of New Residential

Suppression System Technologies

Principal Investigator

Daniel Madrzykowski

Fire Safety Engineering Division

301-975-6677

Sponsor

Federal Emergency Management Agency

U.S. Fire Administration

Objective

To develop a demonstration program based on

technical information for system design and full

scale fire suppression tests for Limited Area

Dwelling Sprinkler Systems and Residential

Water Mist Fire Suppression System

technologies.

Problem

The United States Fire Administration (USFA)

has been involved in the research and

development of the Limited Area Dwelling

Sprinkler Systems (LADSS) and Residential

Water Mist Fire Suppression System

(RWMFSS) technologies. Over the last three

years, USFA sponsored research on these

systems in developing residential sprinkler

systems with minimized water requirements.

This research has been conducted by Factory

Mutual Research Corporation, Hughes

Associates Inc., the National Institute of

Standards and Technology, and Underwriters

Laboratories. The USFA would like to develop

a demonstration program to continue their

transfer of information on these technologies to

the fire conununity.

Approach

During FY 1996, BFRL will perform two tasks:

1. Develop a demonstration program based on

technical information for system design and

full-scale fire suppression tests for LADSS

and RMFSS technologies.

2. Conduct a meeting at NIST with speakers

representing USFA research programs and to

conduct full scale fire suppression tests to

demonstrate the technologies.

145
Recent Results

Conducted demonstration Program/Meetings at BFRL, March 12, 1996.

Evaluation of Water Mist System

Technology for Light Hazard

Occupancy Applications

Principal Investigator

Daniel Madrzykowskl

Fire Safety Engineering Division

301-975-6677

Sponsor

Federal Emergency Management Agency

U.S. Fire Administration

Objective

To evaluate the performance of commercially

available water mist system technologies

compared with a NFPA 13/1 3D system for light

hazard/residential occupancies.

Problem

Several types of water mist systems have been

commercially developed for use as fire

suppression systems. The potential benefits of a water mist system include quick-response,

smaller water supply requirements concerning a

sprinkler system and less collateral damage from

excess water. These potential benefits make

water mist systems attractive as an alternative

for occupancies that currently would require a

sprinkler system. If effective, water mist

systems could be used in light hazard

occupancies such as offices and residences.

Currently, an installation standard is being

developed for water mist systems by the

National Fire Protection Association and the

testing laboratories have proposed requirements

for listing of water mist system equipment for

specific applications. However, there is a gap in

the knowledge base regarding the applicability

of the systems to different occupancies. This

study investigates the applicability of a low

pressure, high momentum water mist system to

light hazard occupancies.

Approach

During FY 1996, BFRL will conduct large scale

compartment fire experiments with a commercially available low pressure, high

momentum water mist system technology. A

limited number of fuel packages representative

146
of light hazard occupancies such as offices and

residences will be selected in consultation with

the U.S. Fire Administration (USFA). Replicate

experiments then will be conducted with

sprinkler systems meeting the criteria of NFPA

13/13D for comparison.

Recent Results

New project

Office Building Fire Research

Program

Principal Investigator

Daniel Madrzykowski

Fire Safety Engineering Division

301-975-6677

Sponsor

General Services Administration

Public Buildings Service

Office of Real Property Management and Safety

Objective

To quantify the impact of large fires on

buildings and their occupants, and investigate

the use of current technology/resources for

mitigating the hazards.

Problem

Systems furniture or "work stations" have been

identified as a source of large heat release rate

fires in office buildings. Because of the wide

spread use of systems furniture, the potential

fire hazard in an open plan office environment

needs to be quantified. The conditions in a long corridor (means of egress) adjoining the

fire compartment needs to be determined. If the fire cannot be suppressed in the room of

origin, the impact of sprinklers on the smoke

flow in the corridor is needed. While the

impact of sprinklers has been demonstrated in

BFRL experiments, it has not been included in

the corridor flow model, because the data base

and zone modeling techniques were not

sufficient to continue development of the

corridor flow model including sprinkler effects.

Approach

During the past three years, BFRL has

conducted experiments on examining smoke

flow in a corridor and characterizing the heat

release rates of open plan office fuel packages.

Experiments also were conducted on mitigating

the hazard of such fires.

During FY 1996, BFRL will conduct experiments to model the mitigation effects and

efforts aimed at verifying FPEtool (BFRL's

software used to evaluate hazards and fire

protection strategies in GSA office buildings).

147
Specifically the water spray from the sprinklers

used in the large scale experiments will be

quantified. This information will be used as input to the FIRE DEMAND model and as input for field modeling of the corridor

experiments. Large scale experiments on the

effects of obstructed ceiling flows on sprinkler

activation v\dll be conducted. Experimental

results will be compared with the current

capabilities of FPEtool.

Recent Results

Madrzykowski, D., "Office Work Station Heat

Release Rate Study: Full Scale vs. Bench Scale,"

Interflam'96 Proceedings, Cambridge, England,

March 1996.

Putorti, A.D., Belsinger, T.D., and Twilley,

W.H., Determination of Water Spray Drop Size

and velocityfrom a Low Pressure, High Momentum

Water Mist Nozzle, NIST FR4000, National

Institute of Standards and Technology, May

1995.

Northridge Post-earthquake Fire

Assessment

Principal Investigator

William D. Walton

Fire Safety Engineering Division

301-975-6872

Sponsor

Federal Emergency Management Agency

United States Fire Administration

Objective

To examine the origin and spread of fires and

evaluate the response of fire sprinkler systems

following the Northridge earthquake.

Problem

The Northridge earthquake provides an

opportunity to examine the causes of postearthquake fires, effectiveness of building

systems in suppressing and containing the fires,

damage to the fire protection infrastructure,

management of fire department resources in

response to the fires, and the recovery from fire

damage following an earthquake. Fire sprinkler

systems are one of the most widely used active

fire protection systems in buildings. There is preliminary evidence that the Northridge

earthquake resulted in damage to many

sprinkler systems.

Approach

During FY 1996, BFRL will work with grantees

and contractors to analyze the information

concerning the causes, effects and response to

fires following the Northridge earthquake. The

project will take into account the complex

interactions of events related to fire to

determine the actions which would be effective

in reducing the loss due to fire and maintaining

adequate fire protection after an earthquake.

The principal tasks are:

1. Develop recommendations for retrofit and

new construction to improve the reliability

of fire sprinkler systems and reduce the

recovery time.

2. Develop a methodology which can be used

by fire inspectors to evaluate the condition

of building active fire protection features

following earthquakes.

148
3. Demonstrate the effectiveness of a temporary emergency measure developed at NIST to reduce the spread of fire from the

outside of a structure through windows to

the interior of a structure.

Recent Results

Chung, R, M., Jason, N, H., Mohraz, B.,

Mower, F.W., and Walton, W.D., Eds., PostEarthquake Fire and Lifelines Workshop, Long

Beach, CA January 1995 Proceedings, NIST SP

889, National Institute of Standards and

Technology, August 1995.

Modification of Fire Protection

Requirements for NRC

Principal Investigator

Robert S. Levine

Fire Safety Engineering Division

301-975-6671

Sponsor

U.S. Nuclear Regulatory Commission

Office of Nuclear Regulatory Research

Objective

To support the Nuclear Regulatory Commission

(NRC) develop a new "rule" that will permit

utilities to use performance-based methods to

design fire protection provisions for nuclear

power plants.

Problem

Current regulation is based on Appendix R of

10 CFR 50 which is entirely prescriptive.

Approach

During FY 1996, BFRL will review the status

and problems of using, world wide,

performance-based fire safety design and

regulation in the built environment, and in

nuclear power plants in France and Japan. Staff

will meet with Brookhaven National Laboratory

on probability reliability assessment techniques,

which can be used to rate the importance of

various intervention strategies. NRC

prescriptive fire protection requirements wall be

compared with NFPAs and with other codes

with a view toward reducing the cost of fire

safety where a cost saving is justified. NRC will

be provided technical support to help them

better prepare documents.

Recent Results

Provided interim reports to sponsor.

149
Firefighter Thermal Exposure and

the Performance of Protective

Clothing in Thermal Environments

and equipment in various fire fighting

environments. The prototype will be used to

evaluate instruments and measurement

techniques.

Principal Investigator

James R. Lawson

Fire Safety Engineering Division

Recent Results

Lawson, J., Firefighter's Protective Clothing and

Jliermal Environments of Structural Fire Fighting,

NISTIR 5804, National Institute of Standards

and Technology, 1996.

301-975-6676

Sponsor

National Institute of Standards and Technology

To determine the thermal performance of

firefighters protective clothing by developing

measurement equipment and techniques to

evaluate and measure the thermal exposures

experienced by firefighters while conducting fire

suppression and rescue tasks and the

performance of the firefighter's protective

clothing.

Problem

Firefighters' protective clothing ar\d equipment

have experienced significant performance

improvements over the last few decades;

however, thousands of firefighters continue to

be burned each year. The apparatus presently

used to measure the performance of firefighter

clothing can only subject the clothing to fire

exposures created in the laboratory. No

industrial standards for acceptable performance

exist.

Approach

During FY 1996, BFRL will conduct a literature

survey to identify applicable publications

associated with protective clothing and

equipment thermal measurements, firefighting

operations, burn injuries and performance of

protective clothing. Obtain information from

the fire service and protective clothing

equipment manufacturers to identify special

needs of firefighters and industry. Data

gathered during these studies will be used to

understand the thermal environments better,

firefighter activities and protective clothing, and

equipment issues related to firefighter burn

injuries. BFRL staff will construct a prototype

portable instrument package for measuring the

performance of firefighters protective clothing

150
Development of a Sizing Standard

for Firefighter Protective Clothing

Principal Investigator

James R. Lawson

Fire Safety Engineering Division

301-975-6676

Sponsor

Federal Emergency Management Agency

U.S. Fire Adrrunistration

Objective

To determine the critical factors of work/station

garment size that affect the thermal protection

and work dynamics of firefighters during fire

suppression operations.

Problem

From recent changes in employment regulations

in the fire service the range of firefighter body

sizes has increased. The fit of firefighter

w^ork/station uniforms has become more critical

as it relates to function with and without

protective garments in fire suppression operations. Therefore, a need exists for standardizing

the size of work/station uniforms to enhance

safety and efficiency in fire fighting activities.

In addition, emergency responders from FEMA

have no standards that provide guidance on

protective clothing or equipment required when

they are called to investigate emergencies or

disasters.

Approach

During FY 1996, BFRL will conduct a literature

survey to identify applicable publications

related with the fit and function of firefighter

work/station uniforms and clothing and about

equipment for use by FEMA personnel in an emergency or hazardous environments.

Researchers will obtain information from the

fire services and apparel manufacturers to

identify special needs of firefighters and the

ability of industry to support the firefighter's

needs. Also, data will be obtained from

emergency managers and investigators to

identify their needs for protective clothing and

equipment. Staff will work with ASTM's

Committee F-23 on Protective Clothing and

national Fire Protection Association (NFPA)

comrruttees which produce protective clothing

and equipment standards to develop and

establish standards for firefighter work/station

uniforms. The results will be published in a

guide document on protective clothing and

equipment for use by FEMA emergency

managers, investigators and inspectors.

Recent Results

Developed a draft "Standard Practice for Body

Measurements and Sizing of Fire and Rescue

Services Uniforms and Other Thermal Hazard

Protective Clothing."

151
Large Fire Research Facility

Principal Investigator

Daniel Madrzykowski

Fire Safety Engineering Division

301-975-6677

Sponsor

National Institute of Standards and Technology

Objective

To perform large scale fire experiments and

provide large fire measurement capabilities that

meet the needs of industry and government

customers.

Problem

Use of BFRL's large fire research facility must

be scheduled for timely performance of

experimental programs. Modernization of

equipment and facilities is required to address

issues of environmental and work place safety.

Approach

During FY 1996, BFRL will continue to provide

daily management of the Large Fire Research

Facility, including scheduling tests for timely

execution along with the gradual modernization

of equipment and facilities. Additional short

term improvements will be developed and

executed during the fiscal year, pending

availability of funding. These plans will be

developed with researchers to assure that newly

and updated instruments fit the needs of the

fire program and its customers. BFRL will

develop methods to assure full compliance with

Federal environmental requirements for large

and small scale tests.

Recent Results

Completed a feasibility study for renovating the

emissions control system and began renovations

on the interior of the test bay.
RECENT GRANTS - LARGE FIRE

RESEARCH

1. Computational Modeling of

Large Fire Plumes

Principal Investigator

Professor A. F. Ghoniem

Department of Mechanical Engineering

Massachusetts Institute of Technology

Sponsor

National Institute of Standards and Technology

Objective

To develop a computational based large fire

plume model in which buoyant fluid mechanics,

combustion, radiative transport, and their

mutual interactions are all fundamentally

represented using physically sound

approximations, and well resolved spatially and

temporally.

Problem

Simulation of fire plumes yielding burning rates,

pollutant formation rates and the radiation field

is necessary as a tool for the assessment of the

environmental impact of large fires. Computational modeling of these fires is complicated by the presence of several complex

physical processes, including turbulence,

transport and chemistry. The wide range of

physical scales present in these processes

complicates their numerical modeling even

further. The overall dynamics is essentially

unsteady and thus should be the model.

Conventional numerical approaches could be

very expensive since the domains of these fires are often extremely large.

Approach

To overcome the difficulties described above,

we are developing a computational model of fire

plumes based a Lagrangian simulation of all significant physical processes involved. The

vortex method is used to obtain solutions of the

Navier-Stokes equations, including the

buoyancy terms and the baroclinic terms, using

computational elements distributed along the

layer separating the plume (fuel and products)

and the surrounding (air and products), in the

turbulent regime. The mixing and combustion

processes are simulated using the transport

element method in which only species

concentration and temperature gradients are computed, and only where vortex elements

exist. The fast chemistry assumption is used in

the computation of the burning rate,

temperature and major species distribution.

The concentration of the computational

elements within the narrow zone of plume

boundaries endows the approach with the

necessary efficiency.

During FY 1996, work is underway on

improving the code performance by

incorporating analytical expressions for the

fields (velocity, temperature, density and scalar

concentrations) instead of evaluating them from

elliptic integral expressions. We used the new

code to simulate fire plumes raging over evaporating liquid fuel pools and used the

results to explain the origin of puffing in and

the similarity between fire plume and

isothermal plume puffing. We also have

improved the discreditization accuracy and

incorporated a more accurate diffusion

approach, both are extremely important in

evaluating the burning rate.

We are currently devising a gas radiation

algorithm to incorporate this all important heat

transfer mode which, in the presence of soot, is regarded as the primary heating mechanism for

the pool. The model's computational efficiency,

achieved by using Lagrangian schemes to

simulate each of these processes, should allow

practical simulations to be performed on an

advanced engineering workstation.

Recent Results

Ghoniem, A. F., Lakkis, I., and Soteriou, M.,

"Numerical Simulation of the Dynamics of

Large Fire Plumes and the Phenomenon of

Puffing," accepted for presentation at the

Twenty-sixiii Symposium (International) on Combustion, Napoli, Italy, July 28-August 2,

1996.

153
2. A Study of Two Phase High

Liquid Loading Jet Fires

Principal Investigator

Jay P. Gore

Purdue University

317-494-1452

Sponsor

National Institute of Standards and Technology

Objective

To study visible flame lengths, radiation and

pollutant emission properties of high liquid

loading jet fires, and their gas fired analogs.

Problem

Two phase jet fires result from effective

atomization of a liquid fuel by small quantities

of trapped gases. The oil well fires in Kuwait

are the most prominent example. The visible

flame lengths of such fires increase with

increasing heat release rates even in the

momentum dominated regime. This increase is contrary to existing knowledge. Correlations for

flame length, radiative fractions and pollutant

emission indices for such fires are also not

available.

Approach

An effervescent atomizer burner simulates the

physical processes that occur in accidental fires

involving high liquid loading two phase jets.

We built a small burner for operation in the 10

kW to 60 kW firing rate range and a large

burner for operation in the 30 kW to 200 kW

firing rate range. We have measured: radiative

heat loss fractions, visible flame lengths,

chemical flame lengths, and pollutant emission

indices for several spray fires stabilized on these

burners. Toluene, heptane, methanol and crude

oil were the liquid fuels. The atomizing gas was

methane. A hydrogen pilot flame stabilized the

spray fires.

We defined the chemical flame length of the

spray fires based on the existence of minimal

hydrocarbon concentration (CH4 < 0.05%)

along the axis. We defined the chemical flame

length of acetylene fires based on lower than

0.05% C2H2 concentration along the axis. We

measured: the gas species concentrations by

sampling with a water-cooled probe and

analyzing with a gas chromatography; soot

emission index using sampling on filters

weighed on a microbalance; CO emission index

using a gas filter correlation analyzer, and NO^

emission index using a chemiluminescence

analyzer.

Pollutant emission indices for soot, CO and

NO^ varied significantly with the amount of

atomizing methane.

Measurements of visible flame length for the

large spray fires showed a continued increase

with heat release rate. Analogous experiments

with acetylene/air flames showed that such an

increase occurred for luminous gaseous jet fires as well. Analyses of turbulent non-premixed

gaseous jets show that stoichiometric mixing

occurs at a fixed normalized height above the

injector exit. Therefore, we focused attention

on whether the visible flame length has a fixed

relationship to the length required for turbulent

mixing to complete combustion.

Measurements of the chemical flame length for

both gas-fired and spray fires strongly support

the prediction that turbulent mixing to

complete combustion occurs at a fixed

normalized height above the injector exit.

Thus soot processes such as radiative cooling to

a black exhaust or oxidation to invisible gases

are responsible for the changes in the visible

flame length. These processes are now being

studied in more detail.

Recent Results

Lawler A., Wade R., Sojka P. E. and Gore J. P., "Flame Length and Pollutant Emission

Characteristics of Effervescent Atomizer/Burner

Stabilized Jet Flames," Proceedings oftJie

Technical Meeting of the Central States Section of the

Combustion Institute, 1996.

Wade R. and Gore J. P., "Visible and Chemical

Flame Lengths of Acetylene/Air Jet Diffusion

Flames," ibid.

154
3. Measurement of Flame

Temperature Using IR Technique

and Air-Entrainment Velocity Using

PDPA

Principal Investigator

Kozo Saito

Department of Mechanical Engineering

University of Kentucky

606-257-1685

Sponsor

National Institute of Standards and Technology

Objective

To measure temperature profiles of large scale

liquid pool fires using an infrared imaging

temperature measurement technique (IRITM)

and evaluate the accuracy of the IRITM data;

measure the flow structure at the flame base for

small scale pool fires using a laser sheet particle

track technique; and conduct scaling analysis on

these data.

Problem

The structure of large scale pool fires is of

interest, because it is associated with radiant

emission to the environment, formation of

environmentally unacceptable combustion byproducts, flame blow-off by extinguishment

agents, and other fire safety reasons.

Approach

Design small scale pool fire experiments and

measure temperature profiles in these flames

using IR technique and velocity profiles using a

laser sheet particle track technique. With the

collaboration of NIST and FRI in Japan, have

completed IR temperature measurements for a 15 m diameter crude oil fire. This large scale

fire data can be used as the reference to develop

scaling correlations. Using a commercial CFD

code made it possible to calculate the fire plume

behavior and flow profiles near the flame base.

The results will produce an improved

understanding of the structure of large scale

pool fires.

Recent Results

New project

4. Fire Protection in Large

Industrial Fires

Principal Investigator

Marino diMarzo

Mechanical Engineering Department

University of Maryland

301-405-5257

Sponsor

National Institute of Standards and Technology

Objective

To evaluate and optimize the performance of

fire fighting agents used to protect structures

and to prevent the spreading of fire in large

industrial settings such as large petrochemical

storage facilities.

Problem

The most common active methods to mitigate

and contain large industrial fires in

petrochemical storage facilities encompass water

sprays and water films. These techniques

require massive amounts of water due to the

significant duration of these fires. The water

runoffs are contaminated by the petrochemical

spills and may constitute a significant

environmental concern. An integrated approach

to identify cost effective, environmentally safe

agents and their application strategies is sought.

Approach

The specific goals of this research include: a) the

evaluation of the active techniques currently

used; b) the experimental and theoretical study

of the interactions of the fire fighting agents

with the fire environment; c) the extension of

these findings to identify the optimal agents to

be used; d) the identification of the most costeffective, environmentally safe application

methodology; and e) the setting of guidelines

for the design and performance prediction of

preventive measures and fire mitigation

strategies applicable to large industrial settings.

Protein foams exliibits characteristics which are

of particular interest for these applications.

They show: a) good expansion characteristics to

provide significant volume of foam per unit

volume of liquid; b) good performance about

155
burnback resistance when exposed to fire; and

c) low mobility which makes them ideal to coat

vertical and underhung and horizontal surfaces.

Fire trials, which test the overall performance of

the foaming agents, are available. However, the

data compare the various foams based on the

time before ignition of the protected surface.

Human factors and outdoor uncontrolled

environmental conditions are common obstacles

to the consistent repeatability of these kinds of

tests. Nonetheless, the test procedures and

product rating reflect these overall approach

limitations.

The quantification of the foam performance

when exposed to a controlled fire environment

and the linkage of the foam behavior to its thermal and physical characteristics is the key

to optimize the application strategy and the

foaming agent property requirements. To

achieve this ultimate goal, the research activities

conducted in FY 1995 are focussed on two

major objectives: a) the characterization of the

properties of foams and b) the detailed

modeling of the foam performance.

The first issue to be addressed is the generation

of a repeatable, controlled foam from a waterfoaming-agent-concentrate solution and air. A

laboratory-scale apparatus has been designed

and constructed which enables the generation of

foam with a given expansion ratio (i.e., the ratio

of the foam volume and of the liquid solution

volume). Preliminary observations suggest that

the operating pressure affect the air bubble

distribution within the foam while having little impact on the overall expansion ratio (the

higher the pressure the more uniform the

bubble size). As to the ultimate effect of the

bubble size distribution, insufficient evidence is available at this time to attempt any conclusion.

As the foam is generated, it immediately

initiates to decay. While the foam product,

used in these preliminary studies, could

maintain reasonable structural properties for

many hours after its generation, this behavior

dramatically changes as the environmental

conditions are altered (i.e., high temperature or presence of fire). Measurement techniques to

characterize the foam density, thermal

expansion coefficient, specific heat, thermal

conductivity, radiation absorption coefficient

and viscosity of the liquid solution were

devised. Most of these measurements were

conducted while significant changes occurred in

the foam material especially at higher ambient

temperature conditions. Analysis of the data

collected is still ongoing. Some additional foam

products are also being identified and similar

measurements will be performed on several

foams.

The detailed modeling of the foam behavior

when exposed to a significant radiant flux from

a fire has been completed under a set of

simplifying assumptions. A dimensional

analysis of the terms controlling the foam

destruction process shows that, at high fluxes

(20 kW/m^ and above), a good portion of the

destruction process can be approximated as quasi-steady state. For steady-state conditions,

the most significant contribution to the foam

vaporization process is given by the radiant flux

which is absorbed at significant depth within

the foam layer. The heat input causes the insitu vaporization of the liquid in the foam while

little convective and conductive processes are

present. This behavior of the foam is largely

unexpected and provides most interesting

perspectives for the future investigations.

The experimental apparatus design and

constructed for the characterization of the foam

behavior under fire radiant heat input will be

used to study a variety of foam products.

Extension of the foam performance

measurement and evaluation to the weathering

process before the fire exposures can also be

accommodated in the existing apparatus and

will be pursued along with the appropriate

modeling developments.

Recent Results

Boyd, C.F. &LdiMarzo, M., "Fire Protection

Foam in a Radiative Environment," accepted for

presentation to the National Heat Transfer

Conference, Houston, TX, August 1996.

156
5. A Survey of Occupant Load

Factors and Fuel Load in

Contemporary Office Buildings

Principal Investigator

James A. Milke

Department of Fire Protection Engineering

University of Maryland at College Park

Sponsor

National Institute of Standards and Technology

Objective

To provide a method of determining the

occupant load in a variety of contemporary

office buildings, i.e., open plan vs. compartmented, public vs. private sector.

Problem

Questions have been raised concerning the

accuracy of currently accepted values for

occupant loads in office buildings. The

concerns have resulted from preliminary studies

conducted in open-plan and compartmented

contemporary office buildings.

Approach

A literature survey was conducted to review the

occupant load survey procedure and data

collection forms used previously, e.g., by

Bourdeau at the University of Maryland. This

review resulted in the development of a preliminary data collection procedure and form

for trial use. This approach was used to

conduct an occupant load survey in public- and

private-sector office spaces in the Washington

metropolitan area.

In an occupant load analysis, two parameters

are needed: the number of building occupants

at any given time and the area of the floor

space. Essentially, the approach consists of

counting building occupants present along with

indicating workstations which appear to be

occupied normally. However, accounting for

individuals absent from their workstation is a source of inaccuracy along with workers and

guests moving throughout the building.

Many additional surveys are being conducted to

expand the data base. Supplementing the

building surveys will be analyses of space plans

which show the number of workstations

provided for each office. By comparing the

results from the surveys with the space plans, a

correlation will be derived to permit space plans

to be used to estimate the occupant load.

Recent Results

Milke, J.A., Evaluation of Survey Procedures for

Determining Occupant Load Factors in

Contemporary Office Buildings , NIST-GCR-96-

697, National Institute of Standards and

Technology, 1996.

Milke, J.A., A Survey of Fuel Loads in

Contemporary Office Buildings, NIST-GCR-96-

698, National Institute of Standards and

Technology, 1996.

157

FIRE SCIENCE DIVISION

FIRE SENSING AND

EXTINGUISHMENT

Advanced Fire Detection

Principal Investigator

William L. Grosshandler

Fire Science Division

301-975-2310

Sponsor

National Institute of Standards and Technology

Objective

To develop a test bed for evaluating the

effectiveness of multi-point fire sensors and to

demonstrate its usefulness for emulating

standard smoldering fires.

Problem

Current test protocols and certification

processes have evolved from smoke sensing

principles established decades ago. New sensors

that respond to different aspects of a fire are being developed for this and other applications

that could open new vistas for the fire detection

industry and provide enhanced protection for

their customers. However, existing test methods may not accommodate these new

designs nor are they necessarily equipped to

evaluate those features which might make the

designs attractive to markets.

Approach

During FY 1996, BFRL will develop a new

method for simulating standard fires and

evaluating fire detectors. The simulation

method will have greater flexibility than existing

methods, will perform the evaluation with more

precision, and will accommodate multi-criteria

decision-making algorithms. The new fire- emulator/detector-evaluator (FE/DE) will

consist of a heated wind tunnel with a test section 0.9 m wide by 0.3 m high and about 4

m long. The temperature and velocity will be

controlled and the major gaseous products and

particulate matter will be injected in a prograrrunable manner to produce the desired

levels at the detector location. Additional

measurements will be taken in the two standard

smoldering fires described in European

Standard EN 54 part 9 to provide the proper

input conditions for the FE/DE program.

Recent Results

Grosshandler, W. (ed.), Proceedings of the 1995

Workshop on Fire Detector Research, NISTIR

5700, National Institute of Standards and

Technology, June 1995.

Grosshandler, V^.,A Review ofMeasurements and

Candidate Signaturesfor Early Fire Detection,

NISTIR 5555, National Institute of Standards

and Technology, January 1995.

Grosshandler, W., "Towards the Development

of a Universal Fire Emulator/Detector

Evaluator," 10. International Konferenz Uher

Automatische Brandentdeckung, Proceedings of

AUBE '95, H. Luck (ed.), Universitat Duisburg,

1995.

Richards, R., Munk, B., Plumb, O., and

Grosshandler, W., "Fire Detection and Location

through Inverse Problem Solution," 10. Inter. Konferenz Uher Automatische Branden., Proc. AUBE '95, H. Luck (ed.), Universitat Duisburg,

1995.

161
Fire Suppression Chemistry

Principal Investigator

Gregory T. Linteris

Fire Scier\ce Divisior\

301-975-2283

Sponsor

National Institute of Standards and Technology

Objective

To provide a fundamental understanding of the

detailed chemical steps, by which the most

efficient chemical flame inhibitors act to

extinguish flames, for the fire protection

community to develop the next generation of

suppression agents and technologies.

Problem

Fire suppressants and their application methods

should be effective, fast-acting, economical,

have low toxicity, permit a habitable

environment during suppression, and cause no

collateral damage to the protected space.

Existing suppressants, however, are non-ideal:

water from sprinklers can cause excessive

damage, powdered suppressants leave a residue,

and the currently favored suppressants, the

halocarbons, produce corrosive gases after

passing through a flame. There exists a continuing need for better suppressants and

suppression methods, but limited scientific

understanding of how existing chemical

inhibitors act to extinguish flames hinders

development of new agents. Some chemical

inhibitors are much more effective, up to several

orders of magnitude, than the best halogenated

agent, CFjBr. Although both gas-phase and

heterogeneous chemical mechanisms have been

proposed, the relative importance of each has

not been discussed, and a clear understanding

of the inhibition mechanism does not exist.

Approach

During FY 1996, BFRL will develop and

understanding about inhibition chemistry of

one super-effective chemical suppressant, iron

pentacarbonyl, so knowledge of its mode of

action can lead to development of other agents

with more desirable properties. Experiments

will determine the global properties and the

detailed flame structure of the inhibited flames.

The experimental results be interpreted

through numerical calculations of the flame

structure. An existing counterflow diffusion

flame code will be modified for inclusion of

particle growth, and reaction.

Besides the work on iron pentacarbonyl,

research on halogenated agents is continuing.

Fluorinated hydrocarbons are being promoted

as replacements for CFjBr. A knowledge of the

chemical behavior of fluorinated hydrocarbons

in flames will promote their safe and efficient use in applications where deemed appropriate.

The experimental and modeling results from

both investigations are expected to lead to a unified method of describing, and an improved

fundamental understanding of the mechanisms

of flame inhibition, extinction, and stabilization

relevant to the advanced suppression of fires.

Recent Results

Smyth, Kermit, C, and Everest, David, A., The

Effect of CF3I Compared to CF3Br on OH" and

Soot Concentrations in Co-Flowing Propane/Air

Diffusion Flames, for presentation at the 26th

Symposium on Combustion, July 1996.

Reinelt, D., and Linteris, G.T., Experimental

Study of the Flame Inhibition Effect of Iron

Pentacarbonyl, Halon Optics Technical

Working Conference, Albuquerque, NM, May

7-9, 1996.

Linteris, G. T., and Reinelt, D., "Inhibition of

Flames by Condensed-Phase Agents," in

Interflam' 96, Seventh International Fire Science and

Engineering Conference, Cambridge, England,

Interscience, London, pp. 477-486, March 26-

28, 1996.

Linteris, G. T., and Truett, L. F., "Inhibition of

Premixed Methane-Air Flames by

Fluoromethanes," Combustion and Flame, 105:

15-27, 1996.

Linteris, G. T., "Numerically Predicted Flame

Structure and Burning Rates of Premixed COAr-02-H2 Flames Inhibited by CF3H," accepted

for publication in Combustion and Flame, January

1996.

162
Reinelt, D., and Linteris, G. T., "Experimental

Study of the Inhibition of Prennixed and

Diffuson Flanges by Iron Pentacarbonyl," to

appear in the Twenty-Sixth International

Symposium on Combustion, 77?^ Combustion

Institute, Pittsburgh, PA, January 1996.

Fallon, G. S., Chelliah, H. IC, and Linteris, G.

T., "Chemical Effects of CF3H in Extinguishing

Counterflow CO/Air/H2 Diffusion Flames," to

appear in the Twenty-Sixth International

Symposium on Combustion, The Combustion

Institute, Pittsburgh, PA, January 1996.

Linteris, G. T., andTruett, L., "Inhibition of

Premixed Methane-Air Flames by Halon

Alternatives," Proceedings of International

Conference on Fire Research and Engineering,

Orlando, FL, pp. 153-158, September 10-15,

1995.

225-242, Washington, DC, 1995.

Linteris, G. T., and Gmurczyk, G., "Prediction of

HF Formation During Suppression, " in "Fire

Suppression System Performance ofAlternative

Agents in Aircraft Engine and Dry Bay Laboratory

Simulations," Editor Gann, R. G., NIST SP 890,

pp. 201-318, National Institute of Standards

and Technology, 1995.

Linteris, G. T., and Gmurczyk, G., "Inhibition

of Premixed Methane-Air Flames by Iron

Pentacarbonyl," 15tii International Colloquium on

the Dynamics of Explosions and Reactive Systems,

pp. 298-301, Boulder, CO, July 30-August 4,

1995.

Babushok, V., Burgess, D. R., Linteris, G. T.,

Tsang, W., and Miziolek, A., "Modeling of

Hydrogen Fluoride Formation from Flame

Suppressants During Combustion," Halon

Options Technical Working Conference, pp. 238-

250, Albuquerque, NM, May 9-11, 1995.

Linteris, G. T., and Gmurczyk, G., "Parametric

Study of Hydrogen Fluoride Formation in

Suppressed Fires," Halon Options Technical

Working Conference, pp. 227-238, Albuquerque,

NM, May 9-11, 1995.

Linteris, G. T., "Effect of Inhibitor

Concentration on the Inhibition Mechanism of

Fluoromethanes in Premixed Methane-Air

Flames," Halon Replacements: Technology and

Science, American Chemical Society Symposium

Series, pp. 260-274, Washington, DC, 1995.

Linteris, G. T., "Acid Gas Production in

Inhibited Propane-Air Diffusion Flames," Halon

Replacements: Technology and Science,

American Chemical Society Symposium Series, pp.

163
Low Environmental Impact Fire

Extinguishment

Principal Investigator

William Grosshandler

Fire Science Division

301-975-2310

Sponsor

National Institute of Standards and Technology

Objective

To facilitate the commercialization of promising

low environmental impact fire suppression

technologies by determining the impact of

additives on enhancing vaporization during

interaction of water droplets with a heated

surface and developing a fixture for evaluating

fire suppression efficiency of inert gas generators.

Problem

Current halon alternatives have ozone depletion

potential and/or are significant greenhouse

gases. Other approaches to fire protection have

features that make them less desirable from an

operational standpoint than the halons they are to replace. Certain additives to water have

recently been shown to increase fire suppression

efficiency. Inert gas generators have also been

demonstrated to extinguish engine nacelle fires. Further development of these new technologies

is hampered by a lack of understanding of the

physical processes controlling their dispersion

and by the absence of metrics for establishing

their effectiveness.

Approach

During FY 1996, BFRL will perform

experiments on single droplet impingement on a heated surface. The effects of additive

concentration, droplet size, impact velocity,

impact angle, and surface temperature on the

vaporization process wdll be examined. Stroboscopic photography will be used to characterize

droplet impact dynamics. Through consultations with academia, inert gas generators

manufacturers, and potential end-users, a standard fixture for evaluating current and next

generation of inert gas generators will be

designed.

Recent Results

Grosshandler, W., Gmurczyk, G., and Presser,

C, "Effectiveness of Halon Alternatives in

Suppressing Dynamic Combustion Processes,"

mACS Symposium Series, Halon Replacements:

Technology and Science, A. Miziolek and W.

Tsang, Eds, 1995.

Grosshandler, W., "In Search of Alternative Fire

Suppressants," accepted for C.L. Tien

Symposium on Thermal Science, and

"Engineering in Honor of Chancellor ChangLing Tian," Buckius, R. O. Editor, p. 275-282,

University of Illinois at Urbana-Champaign,

November 14, 1995.

Grosshandler, W., "The Search for

Environmentally Safe Fire Suppressants,"

seminar, Pm/c^tow University, February 1995.

Yang, J. C, and Grosshandler, W. C, Solid

Propellant gas Generators: Proceedings oftiie 1995

Workshop, NISTIR5766, National Institute of

Standards and Technology, November 1995.

Grosshandler, W., and Gann, R., "Low

Environmental Impact Fire Suppression

Concepts," invited paper. Eastern States Sec- tion/Combustion Institute, December 1994.

164
Study of Technology for Detecting

Pre-Ignition Conditions of CookingRelated Fires Associated with

Electric and Gas Ranges and

Cooktops, Phase II

Principal Investigator

Erik L. Johnsson

Fire Science Division

301-975-3083

Recent Results

Johnsson, E. L., Study of Technologyfor Detecting

Pre-Ignition Conditions of Cooking-Related Fires

Associated with Electric and Gass Ranges and

Cooktops: Phase I Report, NISTIR 5729, National

Institute of Standards and Technology,

Consumer Product Safety Commission,

Washington, DC, p. 115, October 1995.

Sponsor

The Consumer Product Safety Commission

Directorate for Engineering Sciences

Objective

To evaluate the methods, materials, and devices

identified in FY 1995 (Phase I) and that can be

used to detect the pre-ignition conditions

identified in Phase I of cooking-related fires and

alert, or intervene, to reduce the risk of cookingrelated fires associated with electric and gas

ranges and cooktops.

Problem

In 1992, there was an estimated 98200

residential fires attributed to range/oven

appliances. These fires resulted in an estimated

4670 injuries, 220 deaths, and property loss of

$279 million. Approximately two-thirds of the

range/oven related fires involved food.

Currently, there is only a basic understanding of

the pre-ignition conditions of food fires that

might be used as indications of an incipient fire

and of the performance of devices that might be

used to detect and warn of such conditions.

Approach

During FY 1996, BFRL will addresses this work

as two tasks:

1. First, information on the previously

identified devices will be obtained, and the

most promising technologies will be obtained

for testing.

2. Second, the feasibility of differentiating

between normal cooking and approaching

fire conditions and the performance of the

devices in recognizing the differences will be

evaluated through a series of instrumented

cooking experiments.

165
Fire Detection Strategies for High

Bays

Principal Investigator

William L. Grosshandler

Fire Science Division

301-975-2310

Sponsor

National Aeronautics and Space Administration

NASA Headquarters

Objective

To provide NASA with guidance on selection

and placement of fire detectors for protecting

high bay spaces with ceilings between 9 m and

18 m.

Problem

Present guidelines for fire detector placement

extend only to rooms wdth ceiling heights less

than about 9 m. NASA has a special need to

address fire protection issues for high bay spaces

because many facilities exist with ceiling heights

greater than 9 m, and in which a variety of

functions are performed that are critical to the

NASA strategic plan.

Approach

During FY 1996, BFRL will determine the

response of smoke and heat detectors to jet fuel

pool fires with heat release rates up to 12.5

MW using data from its full-scale tests conducted in a 15 m high aircraft hangar during

1995 under Department of the Navy

sponsorship. The data will be put into a form

that will allow comparisons of fire model

predictions to the experimental results. The

veracity of standard zone models such as BFRL's Consolidated Fire and Smoke Transport

Model (CFAST), DETACT-QS and LAVENT

will be challenged by comparing their

predictions with the experiments in the 15 m

high hangar. Algorithms to be tested include

the predicted temperature structure of the

ceiling jet and the temperature versus height

and fire size of the plume models. Plume

correlations not included in the zone model

algorithms also will be compared with the

experimental data. Suggested modifications of

zone model algorithms wdll be documented

based on comparisons of predictions with

experiments. Modeling of the experimental

data will also be done using HARWELL

FLOWSD (a commercial package computer

model that simulates fluid dynamic and heat

transfer using a finite difference approach) and

large-eddy-type simulations. Of primary

interest is the comparison of plume temperature

and ceiling jet temperature profiles using

different turbulence approximations. In addition, ceiling jet velocity measurements will

be compared wdth predictions of the CFD

models.

Recent Results

Davis, W. D., Notarianni, IC A., and Tapper, P.

Z., "Modeling of Smoke Movement and

Detector Performance in High Bay Spaces,"

Proceedings of International Conference on Fire

Research and Engineering, Lund, D. Editor,

Society of Fire Protection Engineers, pp. 307-

311, September 1995.

166
Analysis of High Bay Hangar

Facilities for Detector Sensitivity

and Placement

Principal Investigator

Darren L. Lowe

Fire Sder\ce Divisior\

301-975-6667

Sponsor

Department of the Navy

Naval Facilities Engineering Command

Objective

To develop a comprehensive report of the full

scale test results conducted during FY 1995.

The report will analyze experimental data on

flame detection, smoke detection, and smoke

movement in high bay aircraft hangars using

aviation fuels so that decisions regarding

appropriate fire protection for these spaces can be made.

Problem

Fire protection criteria for aircraft hangars

employ "best engineering judgement" using

NFPA codes and standards that are based on

maximum ceiling heights of 9. 1 m. For years,

DOD and the private sector have extrapolated

data from research conducted in buildings with

conventional ceiling heights. There are no

actual data to support the current design

practices for fire detection and suppression

systems that may be 30.4 m or more above the

fuel level. The effects of stratification, wind,

and the movement of smoke and heat in high

bay areas such as aircraft hangars are not

presently known. Consequently, the reaction

time and effectiveness of fire detection and

suppression systems in aircraft hangars pose

many questions.

r

Approach

During FY 1996, BFRL will write a report on

research conducted in two high bay hangar

facilities. The report will include descriptions of

all detection systems used, building and test site

specifications, test protocol, conditions, and

analysis of all data gathered. The report will

consist of two volumes, the first to be used as a guide or reference manual for Navy and DOD

fire protection engineers, and the second

volume will provide numerical results for

validation of CFD models.

Recent Results

Conducted and analyzed full-scale tests to

decide criteria for detector placement and the

overall effectiveness of various type of detection

systems.

Notarianni, IC A., Gott, J. E., Davis, W., Lowe,

D., and Laramee, S., "Analysis of High Bay

Hanger Facilities for Detector Sensibility and

Movement," C. Franks, and S. Grayson,

Editors, Interflam '96, Interscience

Communication Limited, London, pp. 487-496,

1996.

167
RECENT GRANTS - FIRE

SENSING AND

EXTINGUISHMENT

1 . Detection of Fires Through

Reflected Radiation

Principal Investigator

Yudaya R. Sivathanu

School of Mechanical Engineering

Purdue University

317-494-9364

Sponsor

National Institute of Standards and Technology

Objective

To study a new type of fire detector that is based on a statistical analysis of the apparent

source temperatures of natural fires and the

power spectral density of the radiation

emanating from them.

Problem

Current fire detectors include smoke,

temperature, and radiation emission sensors. The smoke and temperature sensors detect fires

based on the temperature or smoke density in

its immediate vicinity. Therefore, a significant

time delay is experienced between the initiation

and the notification of the fire since the

combustion products have to diffuse or convect

to vicinity of the detector. In addition, in the

presence of impermeable barriers, the fire is not

detected even in its advanced stages.

A new type of fire detector being studied in the

project uses two channels of information

simultaneously. The radiation intensity

emanating from a fire is measured at two closely

space wavelengths in the near-infrared region of

the spectrum. The detection of a fire is based

on a statistical analysis of the resulting time

series of apparent source temperatures.

During the design and construction of

commercial buildings, front end evaluation of

fire safety provisions are becoming increasing

important. To assist architects in designing

residential and commercial buildings with

improved fire safety features, it is often

necessary to determine apriori the optimum

number of fire detectors and their locations

within the structure. The second part of the

present project involves developing a numerical

model than can predict accurately the

anticipated behavior of the near-infrared fire

detector within an enclosure. Toward this end,

a numerical model than can calculate the

radiation intensity incident on the fire detector

from direct and also reflected radiation is being

developed. For realistic predictions of the

response of the near-infrared fire detector, the

optical properties of common building materials

and the geometrical shapes of typical residential or commercial structures must be used in the

simulations.

Approach

The first task undertaken is characterizing the

radiation emanating from the standardized test

fires. The spectral radiation intensities

emanating from the test fires at 900 nm and

1000 nm were measured using two

photomultiplier tubes that had a 150° view

angle. The time series of spectral radiation

intensities at these two wavelengths were

converted to instantaneous apparent source temperatures assuming that the emissivity of

the source varies inversely with wavelength.

Spectral radiation intensity measurements have

been completed for two of the six test fires. The two standardized test fires characterized so

far in this project are a haptene pool flame and

a foam smoldering fire. For these two fires, the

apparent source temperatures obtained from

direct and reflected radiation are between 1200

K and 2400 IC The power spectral density

(PSD) of the apparent source temperatures of

these fires show that most of the energy of the

fluctuations is concentrated at low frequencies

(between 0 Hz and 40 Hz). This is typical of

most natural fires. Therefore, an algorithm

which gives a positive response if 40 percent of

the apparent source temperatures are between

1200 K and 2400 K and 40 percent of the

energy of the fluctuations is between 0 Hz and

40 Hz have been chosen as a trial fire detection

algorithm. This algorithm will be tested using

the standardized test fires both for sensitivity to

starting fires and for incidences of false alarms.

168
The numerical model to determine the response

of the fire detector involves the computation of

the radiation intensity incident on it from fires

within an enclosure. A statistical approach is used to calculate a large number of photon

trajectories from the fire to the detector,

including multiple interactions with the walls of

the enclosure. The probability associated with

the photon trajectories are calculated using a

discrete probability function method which

substantially reduces the errors introduced by

conventional Monte-Carlo simulations. Initial

calculations using the discrete probability

function method for an axisymmetric geometry

has been completed.

Recent Results

Sivathanu, Y. R., and Tseng, L. IC,

"Characterization of Radiation Properties of

Fires Using Multi-Wavelength Measurements,"

Fall Technical Meeting of the Central States Section

of the Combustion Institute, 1996.

Sivathanu, Y. R., and Gore, J. P., "Radiative

Heat Transfer Inside a Cylindrical Enclosure,"

Symposium on Fire and Combustion Systems,

1 996 International Mechanical Engineering Congress

and Exposition.

2. A Theoretical and Experimental

Investigation on Physical, Thermal

and Chemical Effects of Condensed

Phase Fire Suppressants

Principal Investigator

Harsha IC Chelliah

Department of Mechanical, Aerospace

and Nuclear Engineering

University of Virginia

804-924-6037

Sponsor

National Institute of Standards and Technology

Objectives

To quantify the physical, thermal and chemical

effects of condensed-phase fire suppressants in

extinguishing counterflow laminar flames by

experimental and computational techniques.

Problem

The production of chemical fire suppressants

containing Br-atoms (e.g., CF3Br halon 1301)

has been banned because of its adverse effects

on the upper-atmospheric ozone layer. On a mass basis, sodium bicarbonate (NaHC03) is known to be more effective than halon 1301,

certainly, far more effective than most alternate

gas-phase fire suppressants. Yet, the underlying

physical, thermal and chemical effects of such

condensed-phase suppressants are understood

only at a qualitative level.

Recent experimental results with varying sizes

of NaHC03 particles have shown counter

intuitive trends on suppression effectiveness.

To understand these results and provide

information valuable in the search for

alternative fire suppressants, a comprehensive

experimental and theoretical approach is adopted in the present work.

Approach

Nonpremixed flames of hydrocarbon fuels and

air, established in a steady, laminar, counterflow

field, provide an excellent configuration for

theoretical and experimental studies directed at

better understanding the fundamental

characteristics of fire suppressing agents. This

169
configuration is especially useful for studies

involving condensed-phase agents, such as sodium bicarbonate powder (NaHCOS) and

water droplets, because of the complex

interactions occurring between the two phases.

For example, introduction of condensed phase

fire suppressants with air or fuelstreams can

exert physical effects through drag forces and

modification of transport properties, thermal

effects through heats of decomposition,

sublimation, vaporization, modification of heat

capacity, thermal radiation, etc., and chemical

effects through the inhibition reaction pathways

(both homogeneous and heterogeneous). Based

on detailed theoretical models, extraction of the

dominant contributions from the above list requires careful validation of the model with

experimental data, for a wide range of

conditions. For planar flames established

within the mixing layer, the axial velocity

gradient, or the flow strain rate, at flame

extinction provides a convenient parameter to

quantify the suppression effectiveness.

Numerical calculations are being performed to

determine the chemical, thermal and physical

contributions of NaHCOS and fine water

particles on the extinction strain rate. An

Eulerian-Eulerian formulation is adopted to

describe the two-phase conservation equations.

As part of this study, the chemical kinetic,

thermodynamic and transport data of the

intermediate gaseous products of NaHCOS are being compiled and the chemical effectiveness

of some of these gaseous intermediates in

suppressing counterflow nonpremixed flames

has already been investigated. In particular, the

strain rate at extinction of counterflow CH4/air

nonpremixed flame was shown to decrease by

12 percent due to the addition of 0.1 percent

NaOH by mass to the air stream. With the

two-phase flame code being developed, not only

these chemical effects, but other physical and

thermal effects will be investigated and detailed

comparisons with experimentally measured

extinction strain rates will be made. In the

supporting experiments, an enclosed,

counterflow burner has been designed and is being built with provision for introducing

condensed-phase suppressing agents with the

air-stream. The enclosed feature of the burner

is mainly for safety reasons, but could be used

to investigate pressure effects as well. An

interchangeable fuel feed system is being

developed to test the suppression effectiveness

of condensed phase agents against gaseous and

liquid fuels. Initial 2D simulations have shown

that non-uniform flow at the jet exit can affect

the flame shape. Because of the seeding of the

air stream with the condensed phase agents, use

of screens is not an option to make the flow

uniform. Therefore, con verging nozzles will be

used to obtain uniform flow at the jet exit.

Additional nitrogen shroud flow is provided for

dilution and for avoiding secondary flames.

The focusing and collecting optics of the LDA

system are mounted on Klinger stages (with

rated accuracy of 2 ''m) and is traversed up and

down to map the velocity field. During the first year, the goal is to characterize the effectiveness

of various sizes of NaHCOS particles (ranging

from 1 to 50-1- "m) in suppressing nonpremixed

gaseous flames, based on the local extinction

strain rate measurements using the LDA

system. In subsequent years, advanced laser

diagnostic facilities will be used for point

measurements and planar imaging of the

temperature and species profiles to further

validate the numerical model.

Recent Results

New project

170
3. Investigation of Droplet

Penetrations Through Complex

Openings of Compartments

Principal Investigator

Prof. S. C. Yao

Department of Mechanical Engineering

Carnegie Mellon University

Sponsor

National Institute of Standards and Technology

Objective

To understand the phenomena and mechanisms

of the mist penetration through openings of

compartments.

Problem

Fire frequently starts from equipment

compartments. Yet when mist sprays are

activated, droplets could be hard to penetrate

the openings. The process is complex. For large

droplets, their motions are governed by inertia,

therefore, interception and liquid film re- entrainment could occur. For small droplets

their motions follow the air stream closely and

may not be able to penetrate the compartment

substantially. Furthermore, the structures of

the compartment openings are usually complex.

Approach

Experimental and analytical studies will be

conducted systematically to I. investigate the

ability of droplets penetrating the openings

directly under the effects of aerodynamic drag,

inertia and gravity at various conditions; 2.

examine the droplet impaction dynamics to

structures that the indirect penetration

following the impaction can be estimated; and

3. assess the overall liquid penetration

efficiency.

The studies include:

1. creating a mono-size mist generator using

Impulsed Spray Generator [1,2] invented at CMU,

2. detailed observation on the impaction

phenomena of mono-size droplets [3,4] on

cylindrical wires, screens and slots at wide range

of operations. The processed images will

provide understandings and also

non-dimensional correlations, and

3. analytical modeling of the process in 2-D

configurations.

Recent Results

New project

171

FIRE SCIENCE DIVISION

MATERIALS FIRE

RESEARCH

Flammability of Structural

Composites

Principal Investigator

Tom Ohlemiller

Fire Science Division

301-975-6481

Sponsor

National Institute of Standards and Technology

Objective

To develop quantitative procedures for assessing

the impact of fire on structural composites with

the ultimate goal of materials guidelines that assure fire safety.

Problem

Composites are highly attractive materials for a variety of structural uses but their organic resin

content renders them potentially flammable and

subject to loss of strength in a fire. These two

areas of vulnerability may be coupled since

mechanical loading can yield delaminations

which alter thermal properties. Thus, the

general problem of composite response to fire is extremely complex and we are forced to

approach it in stages. BFRL researchers first

focused on the problem of fire growth over the

surface of a composite and to understand the

conditions which can assure that this growth is minimal. Ideally, this threat should be

assessable from bench-scale tests on the

composite, coupled with appropriate models of

fire growth using inputs from these small-scale

tests. BFRL researchers pursued this approach

in previous work for the Department of Navy

and have had reasonable success in assessing the

potential for upward flamespread on flat vertical

wall surfaces, using models developed for other

materials. However, that work showed that a

typical candidate composite for infrastructure

usage, a flame-retarded vinyl ester/glass

material, is susceptible to fire growth. Thus,

BFRL has explored further technologies for

suppressing surface fire growth. A related

problem is a consensus on appropriate fire

testing technology of composites used for

infrastructure applications; we will be pursuing

industry input on this issue.

Approach

During FY 1996, BFRL will address the issue of

whether fire can spread on a composite. Once

suppression of spread is assured, the issue of fire

endurance to a localized fire exposure remains;

this work will be pursued later. BFRL will

continue to address the control of fire spread by

means of surface coatings (since this appears

more promising than composite resin

formulation changes), identifying promising

coatings in bench-scale tests then assessing their

efficacy by full-scale checks. BFRL will examine

charring, charringAntumescent and ceramic

coatings in its Cone Calorimeter and LIFT

apparatuses for their ability to delay ignition,

depress the rate of heat release and limit lateral

fire spread. A successful coating must do all these things and it must remain firmly attached

to the face of the composite despite severe heat

stresses. In the near future, the focus of this

research will study further aspects of coating

technology and the assurance of appropriate no- load bench-scale and full-scale tests for fire

spread suppression. Mechanical loading may

impact the efficacy of a coating (strain could

dislodge the coating); this work will be

performed in a later year.

Recent Results

Ohlemiller, T., Cleary, T., and Shields, J., "Effect of Ignition Conditions on Upward

Flame Spread on a Composite Material in a Corner Configuration," Proceedings of the 41st

International SAMPE Symposium, Vol. 41, Book

1, SAMPE, p. 734. 1996.

175
Radiative Ignition and Subsequent

Flame Spread Over Cellulosic

Materials

Principal Investigators

Takashi Kashiwagi

Fire Science Division

301-975-6699

Howard Baum

Fire Safety Engineering Division

301-975-6668

Kevin McGrattan

Fire Safety Engineering Division

301-975-2712

Sponsor

National Aeronautics and Space Administration

Lewis Research Center

Microgravity Science Program

Objective

To develop new models that describe the

characteristics of heat transfer and flame spread

along a narrow diameter polymer rod in

microgravity.

Problem

This project is one of NASA Microgravity

Science projects to enhance understanding of

combustion science by taking unique advantage

of a microgravity environment. Knowledge is lacking about the ignition and subsequent flame

spread over a thermally thin cellulosic material

in a microgravity environment.

Approach

During FY 1996, BFRL will develop and debug

a new numerical code based on the full NavierStokes equations as an extension from the

current code based on the potential flow

approximation. The model will be extended to

include smoldering phenomena along a thin

paper. The experimental design, fabrication,

experimental parameters and procedures are being developed v^th researchers at NASA

Lewds Research Center for BFRL's experiments

in the planned USMP-3 Space Shuttle flight.

Experiments in high oxygen atmospheres will be

conducted using the Japanese 10 seconds drop

tower in March 1996 as an extension to the

previous study.

Recent Results

McGrattan, K B., Kashiwagi, T., Baum, H. R,

and Olson, S. L, "Ignition and Wind Effects on

the Transition to Flame Spread in a

Microgravity Environment," Combustion and

Flame, in press.

Nakabe, K, McGrattan, K B., Kashiwagi, T.,

Baum, H. R, Yamashita, H., and Kushida, G.,

"Ignition and Transition to Flame Spread Over

a Thermally Thin Cellulosic Sheet in a Microgravity Environment," Combustion and

Flame, 98: 361-374, 1994.

176
Combustion of a Polymer (PMMA)

Sphere in Microgravity

Principal Investigator

Jiann C. Yang

Fire Science Division

301-975-6662

Sponsor

National Aeronautics and Space Administration

Lewis Research Center

Objective

To determine the burning rates of PMMA

spheres in a low gravity environment under

various ambient oxygen conditions

Problem

The need to use polymeric materials that may

be flammable cannot be eliminated aboard the

space shuttle or the future manned permanent

space-station. Knowledge is needed to

understand potential fire threats caused by the

presence of polymeric materials. The use of

spherical geometry has many advantages ~ a

spherical flame, which is one-dimensional, is amenable to simple mathematical analysis and

facilitates a detailed examination of the many

interesting phenomena associated with the

combustion of a solid phase material without

involving the complications of flame-spread,

which is still an active research area.

Approach

During FY 1996, BFRL will perform fire

experiments using polymeric materials in

reduced gravity achieved aboard a DC-9 aircraft

flying a parabolic trajectory. The sphere will be

ignited using a pair of opposing micro-torches.

A mechanism for deploying an unsupported

sphere will be developed. Experiments using

suspended spheres also will be performed.

Suspended spheres will be obtained by

supporting the spheres at the tip of a thermocouple. Results will be compared with

those obtained under normal gravity condition.

NASA wall provide technical assistance to the

design phase of the experiment and will conduct

flight experiments.

Recent Results

Yang, J. C, and Hamins, A., "Combustion of a Polymer (PMMA) Sphere in Microgravity,"

Third International Microgravity Combustion

Workshop. April 11-13, 1995.

177
Chemical Inhibitor Effects on

Diffusion Flames in Microgravity

Principal Investigators

Gregory T. Linteris

Fire Science Division

301-975-2283

Professor Simone Hochgreb

Massachusetts Institute of Technology

Sponsor

National Aeronautics and Space Adnninistration

Lewis Research Center

Space Systems Branch

Objective

To determine the effects of flame inhibitors on

the physical characteristics (height, shape, color,

and luminosity) and stability limits (ignition,

extinction, lift off and blow-off) of gaseous

diffusion flames in the presence of halogenated

fire suppressants in microgravity; and to

develop quantitative analytical models for the

observed behavior, including chemical kinetic

effects, to understand the mechanisms of

inhibition of halogenated compounds in gaseous

diffusion flames in microgravity.

Problem

Fire safety in space is one main reason to

investigate combustion phenomena in

microgravity. Since halogenated compounds

will remain the fire suppressant of choice in

many space missions, there is a need for

experimental evidence on the effectiveness of

these compounds for diffusion flames under

zero buoyancy conditions.

Approach

During FY 1996, BFRL will perform

experiments of normal and microgravity studies

of laminar jet and co-flow diffusion flames

inhibited by halogenated suppressant in the air or fuel stream. In microgravity, visual and

temperature diagnostics will be used to detect

flame shape, dynamics, and stability limits.

Normal gravity experiments will use additional

chromatographic and spectroscopic diagnostics

besides visual and temperature experiments.

Analytical and computational work will be

performed using existing general 2-D codes with

chemical kinetic models for comparison with

the observed results.

Recent Results

VanDerWege, B. A., Bush, M. T., Hochgreb, S.,

and Linteris, G. T., "Effect of CF3H and CF3Br

on Laminar Diffusion Flames in Normal and

Microgravity," Third International Microgravity

Combustion Conference, Cleveland, OH, April 11-

13, 1995.

VanDerWege, B. A., Bush, M. T., Hochgreb, S.,

and Linteris, G., "Effect of CF3H and CF3Br on

Laminar Diffusion Flames in Normal and

Microgravity," Eastern States Section Meeting/The

Combustion Institute, Worcester, MA, October

1995.

178
Combustion of Silicone

Principal Investigator

Takashi Kashiwagi

Fire Science Division

301-975-6699

Sponsor

Dow Corning Co.

Objective

To understand the combustion mechanism of

siloxane and specifically why the heat release

rate (as measured in the cone calorimeter) of

burning siloxane is nearly independent of

external thermal radiant flux.

Problem

The heat release rate (HRR) of burning

materials increases significantly with an increase

in external thermal radiant flux applied to the

burning surface. This is true for non-charring

materials and for charring materials. However,

the burning behavior of siloxanes differs

markedly from carbon-based materials. Perhaps

most significant, the HRR for siloxanes (chain

length > 15 S -O units) does not increase

significantly with an increase in external

thermal radiant flux. Whereas carbon-based

materials may form products of incomplete

combustion such as soot and carbonaceous

chars, siloxanes form very minimal char but

produce substantial amounts of solid

amorphous silica (SjOj) as a major product of

combustion. Previous studies suggest that

amorphous silica play a significant role in

mediating the burning behavior of siloxanes.

Approach

During FY 1996, BFRL will measure emission

spectra of silica/silane/PDMS flames. First, the

emission spectra of high temperature silica

particles will be measured at visible and IR

wavelengths. Second, the emission spectra of a

small silane flame to observe emission bands in

molecules containing silicon, such as SiO.

Third, a flame burning D4 or other short length

silicone fluid will be used to repeat the spectral

measurements to determine if other emission

bands exist, as compared with the bands

observed in the silica and the silane

measurements.

Next, BFRL will analyze evolved gaseous

products and fluid residues during gasification

of silicones to understand their gasification

processes. Evolved gaseous products of several

silicone fluids (e.g., D4, 50 cs, 1000 cs) exposed

to two different external radiant fluxes in

nitrogen will be trapped at different gasification

stages and the products will be analyzed to

identify them.

Recent Results

Buch, R., Hamins, A., Konishi, IC, and

Kashiwagi, T., "Mass Vaporization Rates and

Radiactive Emission of Pool Burning of Silicone

Fluids," submitted to Combustion and Flame,

1996.

179
Lean Flammability Limit as a

Fundamental Refrigerant Property,

Phase II

Principal Investigator

Carole Womeldorf

Fire Scier\ce Division

301-975-4415

Sponsor

Air-Conditioning and Refrigeration Institute

Objective

To accurately evaluate the lean flanunability

limits of various refrigerant mixtures (R-32, R125, R-134a, and R-245ca) using an improved

counterflow burner.

critical flammability ratio (CFR) will be found

by slowly increasing the fraction of HFC- 125 in

the HFC/air mixture while maintaining the

overall equivalence ratio and strain rate fixed, or by fixing the proportions of all constituents and

slowly increasing the strain rate by increasing

the total flow. Numerical results from

CHEMKIN will provide insight into the kinetic

mechanisms of HFC-32 as a fuel and

predictions of the reduction of flame speed

caused by the addition of non-flammable

refrigerants.

Recent Results

Womeldorf, C, and Grosshandler, W., Lean

Flammability as a Fundamental Refrigerant

Property, Phase II, DOE/CE/238 10-68,

Department of Energy, April 30, 1996.

Problem

A critical element of the risk analysis of

alternative refrigerants is the lean flammability

linnit, which ASTM E681-85 determines.

Variations in flammability limits are observed

depending on the initial conditions chosen for

conducting the test. There is a need to

eliminate these variations and to establish

invariant, fundamental lean flammability limits

(LFL) which can be attributed to refrigerant

mixtures similar to fundamental

thermodynamic properties like the adiabatic

flame temperature.

Approach

During FY 1996, BFRL will develop methods to

permit the aerodynamically improved burner to run with a fully automated flow control system.

Computer control of all flows will permit precise

evaluation of extinction points for preset strain

rates or equivalence ratios. The new burner will

be calibrated using CH^ to ensure that the

facility can reproduce the published values of

the lean flammability limit. The lean

flammability limit of HFC-32 and air will then

be examined for different humidities and

geometries. The fuel/air equivalence ratio will be

varied about the stoichiometric point and the

strain rate will be adjusted to identify the most

robust mixture (normally slightly rich for

hydrocarbon flames). The lean flammability

limit of HFC-32 wdll be determined using the zero strain rate extrapolation method. The

180
Calibration Facility for Particle Size

and Concentration

Principal Investigator

George W. Mulholland

Fire Science Division

301-975-6695

written and the particles will be available

purchase.

Recent Results

Four calibration sizes are available for the

calibration of surface scanners and other

particle sizing instrumentation.

Sponsor

National Institute of Standards and Technology

Objective

To develop a facility for accurately measuring

particle size and concentration and for

depositing monodisperse particles of specified

size, number, and chemistry on calibration

artifacts.

Problem

The detection, quantification and

characterization of particulate contamination

on semiconductor surfaces is essential to

advanced semiconductor manufacturing. The

present practical limit for particle detection is

0. 1 nm diameter. The National Technology

Roadmap for Semiconductors calls for the

ability to detect and quantify particles with

0.06 iim equivalent diameter by 2001. There is a need for accurately sized monodisperse

particles in the size range from 0.07 /tim to 0.2

fim for developing and calibrating improved

wafer scanners.

Approach

During FY 1996, BFRLwill collaborate with

NIST's Electronic and Electrical Engineering

Laboratory (EEEL) to calibrate a voltage divider

to provide an accurate calibration tool for

measuring the collector rod voltage of the

differential mobility analyzer (DMA). This is essential for performing accurate measurements

with the DMA. An experimental design will be

developed for accurately sizing four sample sizes

with nominal diameters of 72 nm, 89 nm, 125

nm, and 180 nm by EEEL and the University of

Minnesota. Final selection of the samples to be

measured will be made after completing

electron microscopy analysis. Screening

measurements were completed last year on 22

samples using the DMA. Upon completion of

the measurements and analysis, a paper will be

181
Burning Rate of Real Materials

Principal Investigators

Takashi Kashiwagi

Fire Science Division

301-975-6699

Ken Steckler

Fire Science Division

301-975-6678

Kathy Butler

Fire Science Division

301-975-6673

Steve Ritchie

Fire Science Division

301-975-5441

Sponsor

National Institute of Standards and Technology

Objective

To determine global parameters that can

represent gasification characteristics of single

component materials, for use in calculating

burning rates of the real materials when heat

feedback rates is provided, and tabulate their

values for many plastics and to apply results to

composite materials (e.g., a fabric with a foam,

mattresses, fiber reinforced composites).

Problem

Now we do not have models that can calculate

the burning rate (heat release rate) of real

materials such as buildings contents. Therefore, a fire source is generally prescribed or estimated

from bench scale tests. To improve the

prediction of fire hazards, accurate description

of fire sources is urgently needed.

Approach

During FY 1996, BFRL will derive the global

parameters from the comparison of measured

gasification rates of selected real materials and

theoretically calculated weight loss rates. The

gasification rates will be measured in nitrogen

atmosphere under several different radiant

fluxes. One dimensional heat conduction model

with a global degradation reaction will be nondimentionalized and key parameters (hopefully

as low as two) will be defined. The weight loss

rates will be calculated at the external fluxes as a function of the parameters.

Recent Results

Choi, M. Y., MulhoUand, G. W., Hamins, A.,

and Kashiwagi, T., "Comparison of the Soot

Volume Fraction Using Gravimetric and Optical

Techniques," Combustion and Flame, 102: 161-

169, 1995.

Choi, M. Y., Hamins, A., Rushmeier, H., and

Kashiwagi, T., "Simultaneous Optical

Measurement of Soot Volume Fraction,

Temperature, and CO2 in Heptane Pool Fires,"

Twenty-Fifth Symposium (International) on

Combustion, Jlie Combustion Institute, 1471-

1480, 1994.

Kashiwagi, T., "Role of the Condensed Phase in

Polymer Combustion and Flammability,"

Twenty-Fifth Symposium (International) on

Combustion, Uie Combustion Institute, 1423-

1437, 1994.

182
High Heat Flux Measurement

Standards

Principal Investigator

William L. Grosshandler

Fire Science Division

301-975-2310

Sponsor

National Institute of Standards and Technology

Objective

To develop a convective heat transfer facility for

calibrating heat flux gauges, to develop a concept for a gas phase conduction facility to

extend the calibration range to 100 kW/m^, and

to develop for industry, new techniques for

applications to critical technologies.

Problem

Standard methods exist for calibrating thermal

radiation detectors at flux levels extending to 10

kW/m^ using controlled blackbody cavities, and

up to 40 kW/m^ using a monochromatic laser

radiation source. However, heat flux

transducers are often used under conditions

where convection is dominant, where radiation

emanates from a source with different spectral

character, or where the flux levels exceed 40

kW/ml

Approach

During FY 1996, BFRL will complete

construction of an experimental facility

consisting of a wind tunnel with a heated wall

in which a heat flux transducer can be mounted

flush. Air at a cooler temperature will flow

through the duct in a precisely controlled

manner. The gas temperature and velocity will

be variable, with heat fluxes at the surface

designed to be preset between 0.5 kW/m^ and

5.0 kW/m^ within an uncertainty of less than ±

5 percent. Flow visualization, hot-wire probing,

thermocouples, and temperature sensitive liquid

crystals will be used to measure the temperature

fields in the air and on the surface beside the

flux gauge. Numerical simulations by NIST co- workers in the Chemical Science and

Technology Laboratory and the Electronic and

Electrical Engineering Laboratory will be

consulted to refine the design and minimize

uncertainties. In a second facility, the guarded

hot-plate concept will be extrapolated to

produce heat fluxes up to 100 kW/m^. A 1.0

mm thick layer of helium will separate two flat,

polished copper plates maintained at a temperature difference of several hundred

degrees. This type of construction should

minimize the contribution of radiation and

convection to the conductive heat transfer.

Recent Results

Moffat, R. J., and Darek, C, Final Report on the

NIST/NSF Workshop on Heat Flux Gage

Calibration, unpublished (available from W.

Grosshandler, BFRL, NIST, Gaithersburg, MD

20899), January 23-24, 1995.

183
Evaluation of Fire Barrier

Performance

Principal Investigator

Kenneth D. Sleekier

Fire Science Division

301-975-6678

Sponsor

U.S. Nuclear Regulatory Commission

Office of Nuclear Reactor Regulation

Objective

To provide technical support to Nuclear

Regulatory Commission (NRC) staff in review

and evaluation of technical issues to fire-barrier

systems in nuclear power plants.

Problem

The NRC requires technical assistance for

evaluating the fire performance of certain fire

barrier systems intended to satisfy the fire

protection of safe shutdown capability as specified in certain NRC documents.

Approach

During FY 1996, BFRL will conduct a series of

reduced-scale fire-endurance tests on fire-barrier

systems in use in U.S. nuclear power plants

(NPP). A series of mechanical tests will be

performed on subliming fire-barrier materials to

confirm the mechanical properties provided by

the vendor of the subject materials. BFRL will

integrate into a single document three of its 1994 NRC Letter Reports on the history of the

development of the ASTM E-1 19 temperaturetime fire-severity curve, the history of past

efforts to develop curves for other specific

applications; and an assessment of the

feasibility of developing and implementing

nuclear-power-plant (NPP)-specific fire-severity

curves.

Recent Results

Cooper, L, Y., and Steckler, ICD., Methodology

for Developing and Implementing Alternative

Temperatare-Time Curves for Testing the Fire

Resistance of Barriers for Nuclear Power Plant

Applications, NISTIR5842, National Institute of

Standards and Technology, May 1996.

Furniture Flammability

Principal Investigator

Tom Ohlemiller

Fire Science Division

301-975-6481

Sponsor

National Institute of Standards and Technology

Objective

To develop the technical basis, ultimately

expressed as guidelines for furniture

manufacturers, to design upholstered furniture

with a controlled rate of heat release.

Problem

Current furniture, particularly for residences, can produce large, rapidly growing fires that can

lead to room fiashover. Lacking are viable

techniques to preclude this fiashover

phenomenon by limiting the peak rate of heat

release. Since other materials, such as carpeting

and drapes can rapidly contribute to the heat

release from a chair fire, allowable peak heat

release from upholstered furniture should not

exceed 500 kW. The recent European

Community Combustion Behavior of

Upholstered Furniture study (ECCBUF)

showed that most residential-type furniture

undergoes very non-ideal behavior before

reaching its heat release rate peak (e.g., large

geometry changes occur or a floor pool fire

occurs). The CBUF study did not offer viable

modeling alternatives. Recent efforts at correlations between Cone Calorimeter data

and full-scale performance have had some

success but there are indications that existing

correlations are of limited validity. They have

not been well enough guided by a physical

understanding of the problem.

Approach

During FY 1996, BFRL will attempt to relate

Cone Calorimeter and LIFT behavior to fullscale through appropriate models. This is made

more attractive because of one outcome of the

CBUF study - the development of a technique

to predict Cone furniture composite behavior

from the Cone behavior of the individual

materials. The models and supporting

184
experiments will be developed in stages,

beginning with isolated, single flat cushions,

either horizontal or vertical. The modeling

effort will attempt to take advantage of

associated BFRL research related to room

surface fires. The goal, for each cushion surface

orientation, is an adequate semi-quantitative or even correctly qualitative model which captures

the important parameters for a fire growing on

such a cushion from an arbitrary ignition

condition. Once the modeling for isolated

cushions, as verified by comparisons with

experiments, succeeds in capturing all of the

qualitative dependencies of the heat release rate

history, an attempt will be made to develop a

quantitative correlation between the input

parameters, inferred from the bench-scale tests,

and full-scale behavior. This is roughly the type

approach BFRL used to correlate successfully a

limited portion of its previous chair results (the

most ideally behaved subset). Next, this

approach will be applied to an interacting pair

of cushions (seat and seatback). The next step

is to elevate the pair of cushions on a framework to introduce the possibility of a floor

fire (usually a consequence of dripping

polyurethane melt) which interacts with the

cushion fire. At each step, the modeling process

is expected to help identify the main

parameters; the model is not expected to

develop quantitative predictions of the heat

release behavior of a variety of chairs. The role

of the correlations is to capture this in an

empirically determined quantitative manner,

useful to manufacturers.

Recent Results

Ohlemiller, T. J., "An Examination of the

Correlation Between Cone Calorimeter Data

and Full-Scale Furniture Mock-Up Fires,"

Proceedings oftJie International Conference on Fire

Research and Engineering, Society of Fire

Protection Engineers, p. 217, Boston, MA,

1995.

Test Method Development for

Cigarette Ignition Propensity

Principal Investigator

Richard G. Gann

Fire Science Division

301-975-6866

Sponsor

National Institute of Standards and Technology

Objective

To respond to issues about test methods for

cigarette ignition propensity and toxic potency

measurement.

Problem

BFRL completed a method for measuring the

relative likelihood that a cigarette will ignite

soft furnishings. Expected comments on the

method will require analysis and response.

BFRL also completed work on a test method for

the toxic potency of smoke from burning

products. The method is under discussion in

ASTM and NFPA. Participation in these

activities will require presentations of further

analysis of the research.

Approach

During FY 1996, BFRL and NIST's Information

Technology Laboratory will prepare responses,

as needed, to issues about the methods. The

responses are expected to require further

analysis of the data.

Recent Results

BFRL's research served as the bases for three

Standards:

1. Cigarette ignition propensity test method,

introduced into ASTM E-5. 15 by ATMI,

2. Smoke toxic potency test method (NFPA

269), has cleared the Fire Test Committee,

and

3. Revised version of ASTM E- 1 678 was

constructed to include both pre- and postflashover fire evaluations.

185
Polymeric Film Applied to Glass

Principal Investigators

Jeff Gilman

Fire Science Division

301-975-6573

Emil Simiu

Structures Division

301-975-6076

Sponsor

General Services Administration

Public Building Services

Objective

To search English language bibliographic

databases for research reports, test data or other

available information in the literature on: 1)

blast effects on architectural glass; 2)

performance of polymeric film on glass under

blast conditions; 3) the application, durability

and maintainability of polymeric films on glass,

and prepare a report for the General Services

Administration (GSA) summarizing the

literature found in the search.

Problem

A report by the Department of Justice,

Vulnerability of Federal Facilities, prompted by the

terrorist attack in Oklahoma City, calls for the

application of polymeric film to exterior glass in

Federal buildings to reduce the possibility of

damage due to flying glass from explosive blasts.

However, before undertaking an extensive

retrofit of all Federal facilities, GSA requested

BFRL's technical assistance to study this topic

and report the findings.

Approach

During FY 1996, BFRL will perform on-line

literature searches of four databases:

- RAPRA Abstracts (1972-1995/Aug., 1995

RAPRA Technology Ltd., Engineering

Index);

- Ei Compendex Plus (TM) ( 1970-1 995/Oct.,

1995 Engineering Info. Inc.);

National Technical Information Service

(NTIS) Database, (1964-1995); and

- Architectural Database (1978-1995).

Relevant keywords such as; blast, explosion,

impact, glass, polymer, film, coating, hurricane,

and earthquake were searched. A report

summarizing this literature was written. The

report includes a bibliography.

Recent Results

Gilman, J. and Simiu, E., Polymer Film Applied to Glass: Effectiveness at Mitigating Damagefrom

Flying Glass due to Explosions, NISTIR 5779,

National Institute of Standards and

Technology, January 1996.

186
RECENT GRANTS - MATERIALS

FIRE RESEARCH

1 . Flame Resistance of

Benzocyclobutene (BCB)

Functionalized Copolymers

Principal Investigator

David C. Martin, Ph.D.

Materials Science and Engineering

The University of Michigan

Sponsor

National Institute of Standards and Technology

Objective

To critically evaluate the influence of

benzocyclobutene (BCB) functionalization on

the flame resistance of polymer materials such

as MPDI (Nomex), HBA/HNA (Vectra), and

poly(ethylene terephthalate) (PET).

Problem

The combustion of polymeric materials is a major factor contributing to the deaths and

injuries caused by fires. Hence, schemes to

improve the flame resistance of polymers are of

considerable interest. Here, we explore the

utility of thermally-induced covalent cross linking of polymers to improve their

combustion response. The hypothesis to be

tested is that thermal cross linking will restrict

the flow of molten polymers that would

ordinarily continue to propagate a flame.

Approach

Recently, it has been suggested that BCB

functional groups help to improve the

flammability of polymer materials (Marks,

1994). Here, we evaluate this hypothesis by

synthesizing and characterizing the physical

properties of copolymers containing BCB

functional groups in the backbone of the

molecule. This is accomplished by synthesizing

copolymers with systematic variations in the

amount of terephthalic acid (TA) substituted by

the thermally crosslinkable analog XTA.

Past research in our laboratory has confirmed

that XTA can be incorporated into polymers

such as PPTA (Kevlar) without significantly

changing established processing schemes or the

morphology of the final polymer solid. The

monomer undergoes an irreversible cross linking

reaction at —350 °C, but lies dormant during

conventional solution or melt processing.

Copolymers containing systematic variations in

XTA content have now been prepared from

MPDI (Nomex) and HBA/HNA (Vectra). The

synthesis of PET-co-XTA is currently underway.

Thermal Gravimetric Analysis (TGA) of all XTA

containing copolymers studied to date generally

show a decreasing onset of thermal degradation

temperature with increasing XTA content.

Char contents at 800 °C, which have been

correlated with Limited Oxygen Index values,

increase with increasing XTA content (in

HBA/HNA), and first increase, followed by a

decrease in MPDI.

Scanning Electron Microscopy (SEM) and

Transmission Electron Microscopy (TEM) have

been used to examine the microstructure of the

region near the flame surface. The formation,

growth, and coalescence of voids were noted in

the region underneath the flame surface.

Studies are underway to determine any

systematic changes in the morphology of the

polymer as a function of XTA content.

Future work MviW examine the physical

properties and microstructure of PET-co-XTA

polymers, and copolymers prepared from the

multi functional BCB monomers BXTA, DXTA,

and QXTA.

Recent Results

Martin, D. C, Spilman, G. E., Markoski, L. J., Jiang, T., and Pingel, E., "Flame Resistance of

Benzocyclobutene (BCB) Functionalized

Copolymers," submitted to the Society ofPlastics

Engineers.

Martin, D. C, "Synthesis, Processing, and

Characterization of Thermally Crosslinkable

Thermotropic Copolyesters," final report for the

Summer Faculty Research Program, Phillips

Laboratory, Edwards AFB, CA, 1995.

187
2. Synthesis, Characterization and

Systematic Fire Safety Evaluation of

High Volume and Specialty

Hydrolytically Stable Phosphate

Oxide Containing Polymeric

Materials

Principal Investigator

James E. McGrath

Department of Energy

Virginia Polytechnic Institute and State

University

Sponsor

National Institute of Standards and Technology

Objective

To investigate the influence of organically

bound phosphorus and silicon on fire safety

behavior of polymeric networks materials via cone calorimetry.

Problem

Background research has demonstrated that

incorporation of phosphorus into poly(amide)s,

epoxy networks, polyesters, and polycarbonates

reduce the heat release rate, as judged by cone

calorimetry, while maintaining a good balance

of physical properties expected for the

polymeric material. In general, these materials

are self-extinguishing as judged by traditional

tests, but cone calorimetry also shows that there

is an increase in the carbon monoxide and

smoke content of the phosphorus containing

polymers relative to control materials which,

imdesirably burn rather quickly. The problem

is to discern whether reduction of the aromatic

content can maintain good improvement in

heat release rate, while generating less smoke,

etc. In addition, during this year, initial

experiments have been conducted with siloxane

containing block or segmented copolymers

and/or curing agent^tougheners for epoxy

networks.

Approach

Suitable monomers have been prepared for high

performance copolymers, such as polymides,

and poly(arylene ether)s. In particular,

poly(arylene ether)s containing phosphorus

have been initially screened by cone calorimetry

and do show good behavior with respect to heat

release rate and self-extinguishing

characteristics. In the high performance class of

polymide materials, modified poly(ether imide)s

have been prepared which show excellent char

yields in air and high temperatures in contrast

to the control poly(ether imide)s. Aromatic

phosphate oxide containing diamines were also

used to cure epoxy resins and it was

demonstrated that the reduction in heat release

rate could be obtained. Initial efforts have been

conducted with functional siloxanes as modifiers for polyester, polyamides, and epoxy

networks. Initial aspects of the chemistry have

been successful and preliminary polymerizations

have been conducted demonstrating that the

organosiloxane can effectively modify an epoxy

network. Studies are underway that show the

functional siloxane can also be introduced into

engineering polyesters. Cone calorimetry results

will be sought on these new materials as well as phosphorus systems.

Recent Results

Riley, D. J., Srinivasan, Gungor, A.,

Tchatchousa, C, Sandarapandian, M., and

McGrath, J. E., "Synthesis and Characterization

of Novel Flame Resistant Poly(arlene ethers)s,"

Polymer Preprints, Division of Polymer

Chemistry, American Chemical Society, vol. 37,

no. 1, p. 489-490, 1996.

Tan, B., Tchatchoa, C. N., Vasudevan, V.,

Dong, L, and McGrath, J. E., "Phenyl Ethynyl

Endcapped Arlene Ether Imide

Oligomers/Polymers Containing Diaryl Alkyl

Phosphine Oxide Groups," Polymeric Materials,

Science and Engineering Preprints, vol. 74,

1996.

McGrath, J. E., Ghassemi, H., Riley, D.,

Bhatnager, A., and Kashiwagi, T., "The

Synthesis and Characterization of New

Thermoplastic Fire Resistant Materials," Society

for Plastics Engineerings, ANTEC '96,

Indiannapolis, IN, May 5-9, 1996.

Lee, Y. J., Gungor, A., Yoon, T. H., and

McGrath, J. E., "Adhesive and ThermoMechanical Behavior of Phosphorus-Containing

Thermoplastic Vo\ym\de.s," Adhesion, J., vol. 55,

188
pp. 165-177, 1995.

Wan, I. Y., McGrath, J. E., and ICashiwagi, T.,

"Triarylphosphine Oxide Containing Nylon 6.6

Copolymers," ACS Symposium Series, No. 499,

"Fire and Polymers," YJashmgton, DC, 1995.

Knauss, D. M., McGrath, J. E., and ICashiwagi,

T., "Copolycarbonates and Poly(Arylates)

Derived from Hydrolytically Stable Phoshine

Oxide Comonomers," ACS Symposium Series,

No. 499, Fire and Polymers, Washington, DC,

1995.

3. Modeling of Combustion, Fluid

Mechanics, and Radiation in

Buoyant Turbulent Fires

Principal Investigator

Ofodike A. Ezekoye

Department of Mechanical Engineering

The University of Texas at Austin

512-471-3085

Sponsor

National Institute of Standards and Technology

Objective

To evaluate and develop a computational

strategy to couple gas phase combustion and

soot radiation into simulations of buoyant

flames.

Problem

Soot species radiation is the driving heat

transfer mechanism for many fire scenarios.

Computational approaches to describing the

soot species evolution and subsequent radiative

participation are very much in the

developmental phase. Prior to adequately

characterizing the radiative feedback and

burning rate of a fuel bed, it is imperative to

characterize the flame properties as to soot

loading and radiative strength.

Approach

Lacking significant flow field effects, we have

evaluated and refined models for soot driven

radiative extinction {FY 1994), gas phase and

soot transport, and soot oxidation and

agglomeration processes (FY 1995). In these

studies, combustion dynamics are computed for a spherical, transient, diffusion flame.

Transformations of the conservation equation

into a mixture fraction coordinate by means of

Crocco type transformations, have made the

choice of flow field effectively unimportant. The

strain rate as is manifested in the scalar

dissipation becomes the primary issue. Results

generated for the spherical flames in question

apply to any low strain rate diffusion flame

when presented in mixture fraction space.

As with all flamelet strategies, the laminar

nature of the flamelet implies that direct

189
computation of the necessary combustion

reactions can be performed at any level of

detail. Thus, reaction chemistry can be

specified to be either detailed or simplified.

Various levels of chemical mechanism

specification are investigated in this research.

An appropriate level of physical processes must

be specified for the flamelet such that an

appreciation and intuition for the overall

dynamics present for a simulated large fire flow

field will later be accurately modeled. This

implies that both the soot species and

temperature distributions are accurately

computed initially on the flamelet.

Recent computations have produced good

comparisons with experiments of a micro

gravity diffusion flame. In these computations

finite rate mechanisms are used for the gas and

soot species evolution. In that study, it was

found that the radiative modification of both

the flame temperature field and the burner

surface affected the soot production

significantly. It also was found that oxidation

of soot by the hydroxyl radical could

significantly affect the soot species evolution.

Finally, it was shown that the present spherical

coagulation model used in most soot evolution

models may lead to erroneous conclusions on

the temporal evolution of the soot surface area.

Recent Results

Exekoye, O. A., and Zhang, Z., "Soot Oxidation

and Agglomeration Modeling in a Micro gravity

Diffusion Flame," Combustion and Flame, in

review.

Zhang, Z., and Ezekoye, O. A., "Analysis of

Laminar Acetylene-Air Diffusion Flames Using

Reduced Reaction Mechanisms and State

Relationships," Combustion Science and Technology,

1995.

Zhange, Z., and Ezekoye, O. A., "Acetylene-Air

Diffusion Flame Computations; Comparisons of

State Relations versus Finite Rate Kinetics,"

Proceedings of International Conference on Fire

Research and Engineering, Orlando FL, 1995.

Ezekoye, O. A., and Zhang, Z., "Modeling of a Lagrangian Flamelet with Radiation

Interaction," Combustion Science and Technology,

106, 1995.

Zhang, Z., and Ezekoye, O. A., "Computational

Study of State Relationships for Acetylene-Air

Diffusion Flames with Soot Radiation," HTD

bound vol. 304, ASME NHTC, Portland, OR

August 1995.

190
4. Fire Growth Models for Materials

Principle Investigator

Professor James Quintiere

Fire Protection Engineering

University of Maryland

301-405-3993

Sponsor

National Institute of Standards and Technology

Objective

To determine transient burning rate models

that can be used to generalize data from the

Cone Calorimeter.

Problem

Bench-scale test methods developed by BFRL's

fire program have become standards, and offer

the potential for scientifically based assessments

of flammability. These test methods, based on

the Cone Calorimeter and the LIFT

apparatuses, provide material data on ignition,

flame spread and burning or energy release rate

for small samples. There is a need for using

these data to describe the fire hazard of

materials. The problem is to identify the form

of these data consistent with general models for

ignition, burning rate, and spread.

Approach

A model with good accuracy has been

successfully demonstrated for thermoplastic like

materials. This is based on an integral method

that leads to a closed form analytical solution

for constant heat Hux. As a result, applications

of that model will be examined. First, we have

examined the case of step changes in irradiance

for the thermoplastic case. Good agreement

between the analytical solution and data for

PMMA have been found. Second, we are examining the effect of transient burning rates

on upward flame spread. We have developed

an algorithm using the thermoplastic burning

rate solution. The algorithm also accounts for

the transient effect of the ignition flame, and

the finite mass of the material which controls

burnout. Third, we have extended the structure

of the thermoplastic model to include the

insulating effect of char accumulation. An

algorithm for this charring case has been

formulated to yield mass loss rate, char surface

temperature, and char layer depth. Both

algorithms are being coded so that quantitative

results can be examined. Fourth, we are

investigating the prospect of applying our fire

growth simulation model to a large data base of

commercial materials used in room corner fires. The simulation model would be upgraded to use

the transient burning rate algorithms in

development.

Recent Results

Quintiere, J., and Iqbal, N., "An Approximate

Integral Model for the Burning Rate of a Thermoplastic-like Material," Fire and Materials,

vol. 18, 89-98, 1994.

Iqbal, N., and Quintiere, J., "Flame Heat Fluxes

in PMMA Pool Fires," SFPE Journal, vol. 6, no.

4, 153-162, 1994.

Quintiere, J., Hopkins Jr., D., Iqbal, N., and

Rhodes, B., "Thermoplastic Pool Fires," The

Symposium on Tliermal Science and Engineering in

Honor of Chancellor Chang-Lin Tien, November

14, 1995.

Rhodes, B. T., and Quintiere, J. C, "Burning

Rate and Heat Flux for PMMA in the Cone

Calorimeter," Fire Safety Journal, September

1995.

Hopkins Jr., D., "Predicting the Ignition Time

and Burning of Thermoplastics in the Cone

Calorimeter," MS Thesis, Department of Fire

Protection, U. ofMD, May 1995.

Hopkins Jr., D., and Quintiere, J. G., "Material

Fire Properties and Predictions for

Thermoplastics," submitted to the Fire Safety

Journal, December 1995.

Quintiere, J. G., "Fire growth: a review,"

submitted to the Philosophical Transactions of the

Rcyal Society, April 1995.

Quintiere, J. G., Hopkins Jr., D., and Hopkins,

M., "Room -Corner Fire Prediction for Textile

Wall Materials," 1995 International Conference on

Fire Research and Engineering, September, 1995.

191

FIRE SCIENCE DIVISION

SMOICE DYNAMICS

RESEARCH

Carbon Monoxide Production and

Prediction

Principal Investigator

William M. Pitts

Fire Science Division

301-975-6486

Sponsor

National Institute of Standards and Technology

Objective

To develop a fundamental understanding of the

mechanisms of carbon monoxide formation in

flames sufficient to produce an estimation and

detailed predictive models.

Problem

CO generated by fires in enclosures is responsible for roughly two-thirds of fire deaths.

The conditions necessary and the mechanisms

responsible for the generation of high

concentrations of CO are poorly characterized.

As a result, predicting the generation of CO by

fires is currently impossible. Laboratory fire

models require such a predictive capability such

as BFRL's HAZARD Fire Model.

Approach

During FY 1996, BFRL will perform

fundamental and engineering investigations to

develop appropriate correlations of CO

formation for fires in enclosures and to provide

the necessary knowledge to incorporate the

findings into existing BFRL fire models. The

fundamental investigations will identify the

principal chemical and physical mechanisms

responsible for the formation of high CO

concentrations in fires and to theoretically

justify the use of the engineering correlations.

Ultimately, the findings will be incorporated

into a simple physical model for CO production

in enclosure fires.

Recent Results

Pitts, W. M., "An Algorithm for Predicting

Carbon Monoxide Formation in Enclosure

Fires," submitted for the Fifth International

Symposium on Fire Safety Science, March 3-7,

1997.

Johnsson, E. L, Bryner, N. P., and Pitts, W. M.,

"Fire-Induced Mass Flow into a Reduces-Scale

Enclosure," Fire Safety Journal, in press.

Pitts, W. M., "The Global Equivalence Ratio

Concept and the Formation Mechanisms of

Carbon Monoxide in Enclosure Fires," Progress

in Energy and Combustion Science, vol. 21, p. 197,

1995.

Pitts, W. M., The Global Equivalence Ratio

Concept and the Prediction of Carbon Monoxide

Formation in Enclosure Fires, NIST Monograph

179, National Institute of Standards and

Technology, June 1994.

Pitts, W. M., "Application of Thermodynarruc

and Detailed Chemical Kinetic Modeling to

Understanding Combustion Product Generation

in Enclosure Fires," Fire Safety Journal, vol. 23,

p. 271, 1994.

Pitts, W. M., Johnsson, E. L, and Bryner, N. P., "Carbon Monoxide Formation in Fires by HighTemperature Anaerobic Wood Pyrolysis,"

Twenty-Fifth International Symposium on Combustion, The Combustion Institute, pp. 1455-

1462, Pittsburgh, PA, 1994.

Leonard, S., Mulholland, G., Puri, R., and

Santoro, R. J., "Generation of CO and Smoke

During Underventilated Combustion,"

Combustion and Flame, vol. 98, p. 20, 1994.

195
Species Production for Turbulent

Flame Modeling

Principal Investigators

Kermit C. Smyth

Fire Science Division

301-975-6490

George W. Mulholland

Fire Science Division

301-975-2660

Nelson Bryner

Fire Science Division

301-975-6868

Sponsor

National Institute of Standards and Technology

Objective

To develop an accurate data base and

phenomenological descriptions to establish

models for in-flame species concentrations and

post-flame species yields as a function of

residence time, equivalence ratio, temperature,

and strain and scalar dissipation rates.

Problem

The data base, new metrology, phenomenology,

and models for well-controlled flame environments will provide the foundation for predicting

flame radiation and the production of toxic

gases and smoke for buoyant, turbulent

diffusion flames for a wide range of combustion

conditions.

Approach

During FY 1996, BFRL will select and

experimentally examine laminar flame

environments vidth temperature, residence time,

equivalence ratio, and strain and scalar

dissipation rates characteristic of buoyant,

turbulent flames. Emphasis will be placed on

planar imaging approaches using laser-induced

fluorescence and scattering signatures, and

quantitative measures of the soot field. Initial

studies will focus on time-varying and

underventilated laminar diffusion flames.

Characterize the in-flame and post-flame

chemical species, flow velocity, and temperature

fields. Apply GC-MS and laser ionization-mass

spectroscopy (previously used for graphitic

smoke) to the analysis of the mostly organic

smoke produced during underventilated

combustion. Test and develop models

incorporating the wide range of combustion

conditions using the new data base.

Recent Results

Shaddix, C. R., and Smyth, IC C., "LaserInduced Incandescence Measurements of Soot

Production in Steady and Flickering Methane,

Propane, and Ehtylene Diffusion Flames,"

Combustion and Flames, in press.

Kaplan, C. R., Shaddix, C. R., and Smyth, IC

C., "Computations of Enhanced Soot

Production in Time-Varying CH^/Air Diffusion

Flames," Combustion and Flame, in press.

196
Vortex-Chemistry Interactions in

Methan^Air Diffusion Flames

Principal Investigators

Kermit C. Smyth

Fire Science Division

301-975-6490

William M. Pitts

Fire Science Division

301-975-6486

Sponsor

Gas Research Institute

Objective

To determine how chemical production and

destruction rate for soot, CO, and NO depend

upon local flame conditions.

Investigate a wide range of combinations of the

key parameters, specifically residence time,

rruxture fraction, temperature, and strain and

scalar dissipation rates.

Problem

Increasingly tighter regulations from the Clean

Air Act and its 1990 amendments now control

pollutant emissions. In cases where the

chemical kinetics is well established, e.g., CO

production and destruction, emission levels

cannot be predicted from practical combustion

devices over a range of operating conditions.

Approach

During FY 1996, BFRL will study chemistryflowfield interactions using flickering

methane/air diffusion flames. Axisymmetric

flames will be acoustically locked to a pulsed

dye laser system at 10 Hz, allowing

interrogation of the flame dynamics as a function of height, phase angle, and forcing

amplitude. These flames exhibit a much wider

range of local strain and scalar dissipation rates

than those found in steady, co-flowing laminar

flames. Emphasis will be placed on planar

imaging approaches for species and soot

concentrations, and LDV velocity and thinfilament pyrometry temperature measurements.

These results will provide critical tests of

current models for the production of toxic gases

and smoke from buoyant, turbulent diffusion

flames for a wide range of combustion

conditions.

Recent Results

Smyth, IC C, "NO Production and Destruction

in a Methane/Air Diffusion Flame," Combustion

Science and Technology, 115: 173-194, 1996.

Everest, D. A., Shaddix, C. R., and Smyth, IC

C, "Quantitative Two-Photon Laser-Induced

Fluorescence Imaging of CO in Flickering CH4

/Air Diffusion Flames," Twenty-Sixtli International

Symposium on Combustion, April 1996.

Shaddix, C. R., Harrington, J. E., and Smyth, IC

C, "Quantitative Measurements of Enhanced

Soot Production in Flickering Methane/Air

Diffusion Flame," Combustion and Flame, vol. 99,

p. 723, 1994, comment and reply Combustion

and Flame, vol. 100, p. 518, 1995.

197
RECENT GRANTS - SMOKE

DYNAMICS RESEARCH

1 . Mixing and Radiation Properties

of Buoyant Luminous Flame

Environments

Principal Investigator

G.M. Faeth

Department of Aerospace Engineering

The University of Michigan

313-764-7202

Sponsor

National Institute of Standards and Technology

Objective

To complete measurements of the radiation and

mixing properties of luminous buoyant

turbulent flame environments, and to exploit

these results to develop and evaluate advanced

models of practical unwanted fires.

Problem

Radiation and turbulent mixing from luminous

flames strongly affect the rates of spread,

growth and combustion of unwanted fires; therefore, these properties are important

elements of contemporary models of unwanted

fires that find application for quantifying fire

hazards while avoiding the time and cost of fullscale fire tests. Unfortunately, available

information about soot optical properties are limited although radiation from soot in

luminous flames is the dominant radiation

mechanism of fires. In addition, the

fundamental transport and mixing properties of

the buoyant turbulent flows found in fire

environments are poorly understood which has

impeded the development and evaluation of fire

models. Thus, both issues are being addressed

during this investigation.

Approach

The study of the radiation properties of

luminous flames is concentrating on the optical

properties of soot because continuum radiation

from soot is the most important source of

radiation in fires. Measurements and

computations during initial phases of the study

showed that soot optical properties can be

approximated by the Rayleigh-Debye-Gans

(RDG) scattering approximation while treating

soot as polydisperse mass-fractal aggregates of

primary soot particles. Measurements also

revealed that the mass-fractal properties of soot

aggregates were robust; therefore, current large

uncertainties about the refractive indices of

soot, and how they vary with fuel type and

flame conditions, are the greatest impediments

to reliable estimates of soot optical properties.

In view of these findings, current work is concentrating on soot refractive indices. The

first phase of this work involved in situ

extinction and scattering measurements in the

visible (350 nm to 800 nm), combined with

gravimetric measurements of soot densities and

volume fractions, to yield soot refractive indices

for this wavelength range. Measurements thus

far have considered soot emitted from gasfueled buoyant turbulent diffusion flames in the

long residence time regime where soot

properties are independent of position in the

overfire region and residence time; it was found

that the refractive indices of this soot were

relatively independent of fuel type and agreed

reasonably well with the often criticized

classical measurements of soot refractive indices

of Dalzell and Sarofim. Current work is undertaking similar measurements for more

heavily sooting liquid-fueled diffusion flames,

and is developing ex situ reflectivity

measurements needed to address refractive

indices in the infrared wavelength range.

Subsequent work will consider other types of

soot found in fire environments and will

evaluate radiation predictions for sootcontaining luminous flames using present

methods, based on radiation measurements for

well-characterized luminous laminar diffusion

flames.

The study of buoyant turbulent flows is concentrating on self-preserving buoyant

turbulent plumes because they are fundamental

classical flows that are independent of source

properties and can be numerically simulated

with modest computational requirements.

Present work began with self-preserving round

buoyant turbulent plumes using laser-induced

fluorescence and laser velocimetry to measure

198
mixing and velocity properties. These

naeasurements showed that earlier work, did not

extend far enough from the source to reach self- preserving conditions, and that self-preserving

round turbulent plumes were narrower, and had

larger scaled mean values near the axis, than

previously thought. These observations raised

questions about potential effects of flow

confinement during these experiments, because

ambient coflows due to confinement would also

tend to narrow the plumes; nevertheless, new

experiments addressing these effects showed

that coflows were not a factor and that present

results were properly the outcome of fully

reaching self-preserving conditions. Attention

then turned to measuring turbulence properties

in the self-preserving region and comparing

these measurements with predictions based on

contemporary turbulence models; the results

highlighted several deficiencies of present

models for treating buoyant turbulent flows

typical of fire environments and provided

information needed to develop more effective

methods.

Attention has now turned to the classical

problem of self-preserving plane (or line)

buoyant turbulent plumes for several reasons.

First, the streamwise rates of development of

self-preserving round and line buoyant

turbulent plumes are fundamentally different

which provides a useful evaluation of modeling

improvements needed to treat the complex

flows of practical fire environments. Secondly,

the line buoyant turbulent plume is a necessary

precursor for gaining a better understanding of

turbulent flows along surfaces that are relevant

to burning objects. Finally, reaching self- preserving flow conditions is more difficult for

line than round plumes; therefore, concerns about existing measurements that claim to

represent self-preserving behavior must be

resolved before this information can be

exploited for model development. Current work

is developing the new line-plume apparatus,

with measurements of mixing and velocity

properties to follow. Subsequent work will

address the effectiveness of existing turbulence

models, based on evaluations using present

measurements in the self-preserving region of

line plumes.

Recent Results

Farias, T. L, Carvalho, M. G., Koylu, U. O.,

and Faeth, G. M., "Computational Evaluation

of Approximate Rayleigh-Deby-Gans/FractalAggregate Theory for the Absorption and

Scattering Properties of Soot," /. Heat Trans.,

117, 152, 1995.

Koylu, U. O., Faeth, G. M., Farias, T. L., and

Carvalo, M. G., "Fractal and Projected

Structure Properties of Soot Aggregates,"

Combust. Flame, 100, 621, 1995.

Faeth, G. M., and Koylu, U. O., "Soot

Morphology and Optical Properties in

Nonpremixed Turbulent Flame Environments,"

Combust Sci. Tech., 108, 207, 1995.

Dai, Z., Tseng, L. K. and Faeth, G. M.,

"Velocity/Mixture-Fraction Statistics of Round

Self-Preserving Buoyant Turbulent Plumes," /. Heat Trans., 117, 918, 1995.

199
2. Dynamics, Transport and

Chemical Kinetics of Compartment

Fire Exhaust Gases

Principal Investigators

Uri Vandsburger

Virginia Polytechnic Institute and State

University

703-231-4459

Richard J. Roby

Hughes Associates Inc. 410-737-8677

Objective

The study focuses on determining the

conditions for the transport of high

concentrations of CO to remote locations from

the burning compartment, and the transport

path of CO away from the compartment.

Problem

Over the past decade, the percentage of deaths

from smoke inhalation in building fires has

risen by 1% every year, and was responsible for

75% of the deaths during 1992. Existing

engineering models need to be improved to

accurately predict the amount of CO

transported under certain conditions and the

path of the CO transport.

Approach

The reduced-scale building fire facility at VPI(StSU was arranged with the compartment

(1.22m by 1.52m by 1.22m), which contained a

liquid hexane pool fire, placed on the side at the

end of the hallway (1.67m by 1.22m by 5. 18m)

forming a L-shape. The global equivalence ratio

of the compartment fires was 3.0±0.3 during

the post-flashover period.

The oxygen entrainment into the compartment

fire gas plume entering the hallway controls the

degree of CO oxidation. The size of the

opening connecting the compartment and

hallway, the height of the soffit at the opening

and the hallway upper-layer depth (controlled

by the height of the soffit at the end of the

hallway) all play a role in the entrainment of

oxygen into the plume.

Through varying the upper-layer depth, three

classes of hallways were defined: "semi-infinitely

long," "long," and "short." The "semi-infinitely

long" long hallway characteristically had a

shallow upper-layer (0.0 m to 0.20m), and the

downstream yield of CO was at a minimum

with its magnitude controlled by the opening

size. A 0.04 m^ opening resulted in lower CO

yields (0.02) compared with a 0. 12m^ opening

(0.10). The "long" hallway, which had a medium upper-layer depth (0.20 m to 0.60 m),

generated yields which were a transition

between the low yields of the "semi-infinitely

long" hallway to the high yields of the "short"

hallway. The deep upper-layer (0.60 m and

greater) in the "short" hallway resulted in CO

yields equivalent to or higher than those

measured inside the compartment (0.22), and

were independent of the opening size. The

higher yields were observed in experiments with

external burning where unburned hydrocarbons

(UHC) were oxidized while CO was not.

With the compartment on the side of the

hallway, the flow field in the hallway is highly

three-dimensional resulting in a non-uniform

transport of gases down the hallway. During

the compartment post-flashover period of

"short" and "long" hallway experiments with

external burning, gases containing high levels of

CO (2.0% to 2.5%) first travel across the

hallway. Gases measured containing 1.8

percent to 2.0 percent CO were transported

down the side of the hallway opposite the

compartment, while only 0.8% CO was present

on the compartment side of the hallway. The

non-uniformity persisted in the "long" hallway

experiments for the entire post-flashover period

(140 seconds), while the upper-layer CO

concentration became uniform in "short"

hallway experiments 70 seconds after flashover.

The UHC were oxidized to 1.0 percent after the

gases had traveled across the hallway. Based on

these observations, the Hillhaven nursing home

fire in 1991 was an example of a long hallway.

Of the 23 people residing along the hallway, 1

1

people died on the side of the hallway opposite

the burning room, while only 1 person died on

the burning room side of the hallway.

The zonal models currently used in fire safety

codes, which assume uniform upper-layer

200
species concentrations, are valid in cases with a

short hallway or at times long after the onset of

flashover. Instead, field models should be used

to accurately model smoke and toxic gas

movement in hallways with the burning room

located on the side. Future experiments will be

performed with different fuels (e.g.,

polyurethane foam), and door connecting the

compartment to the hallway. Computer

modeling will be conducted to verify the

experimental results.

Recent Results

Vandsburger, U., Lattimer, B.Y., and Roby, R.J.,

Compartment Fire Combustion Dynamics, Annual

Report, NIST-GCR-95-666, National Institute

of Standards and Technology, 1994.

201
I1
BFRL HEADQUARTERS

OFFICE OF APPLIED

ECONOMICS

Economic Support for the NIST

Advanced Technology Program

Principal Investigator

Stephen F. Weber

Office of Applied Economics

301-975-6137

Sponsor

National Institute of Standards and Technology

Advanced Technology Program (ATP)

methods to estimate economic impacts of ATP

funded research and apply econometric

forecasting and simulation tools to ATP case study projects.

Results

Enhanced software modules for ATP's quarterly

report on Business Plan and Developments.

Completed software for ATP's anniversary

report on Economic and Financial Data.

Objective

To support the economic and program

evaluation missions of ATP by providing

economic modeling services and by designing

and developing economic questionnaires and

implementing them in software to perrrut

electronic submission by ATP awardees of

quarterly and annual reports on economic and

business progress.

Problem

ATP management is developing questionnaires

to track the technological and economic

progress of awardees. Economic consulting is needed to review the questions, and software is needed to implement them in electronic form.

ATP also needs assistance in conducting

economic impact assessments of its projects.

Approach

During FY 1996, BFRL will support ATP by

reviewing the questionnaires for their economic

content and working with ATP economists to

specify data requirements and to design

efficient ATP awardee questionnaires to support

economic impact models. OAE will develop

data structures, files, and data relations for field

data collection and storing questionnaire

responses in a centralized database at ATP

headquarters. OAE will computerize in separate,

executable, software modules each of the six

ATP awardee questionnaires. Some data

validation features and help screens will be

included. OAE also will develop software

utilities for creating distribution diskettes and

for consolidating data from floppy disks into a

centralized database at ATP headquarters.

OAE will work with ATP economists to develop

205
Measurement of BFRL Research

Impacts

Principal Investigator

Robert Chapman

Office of Applied Economics

301-975-2723

Sponsor

National Institute of Standards and Technology

Objective

To help BFRL identify industries impacted by

BFRL research, estimate economic impacts

resulting from BFRL research, and estimate the

return on BFRL's research investment dollars.

Problem

The measurement of economic impacts of

research is a major objective of BFRL.

Managers need to know the impact of their

research programs to achieve the maximum

social benefits from their limited budgets.

Improved methods for measuring economic

impacts is essential to BFRL to help select the

"best" among competing research programs, to

evaluate how cost effective are existing research

programs, and to defend or stop programs based

on their economic impact.

Approach

During FY 1996, BFRL staff will be developing

standard methods for measuring economic

impacts of research projects. The focus is on

measures of net benefits, the benefit-to-cost

ratio, and the social rate of return. These

methods are consistent with ASTM methods of

economic evaluation.

published as two separate reports. The three

studies included:

• The substitution of 235 for 210 pound

shingles in asphalt roofing shingles,

• Improving residential energy conservation

according to ASHRAE 90-75,

• Using the Fire Safety Evaluation System

(FSES) to find the least-cost compliance

with fire-safety performance codes in health

care occupancies.

One report will cover the first two buildingrelated studies; the second report will cover the

last study.

In subsequent years, BFRL staff will develop

techniques for measuring impacts for specific

categories of customers (e.g., by SIC codes).

The objective will be to produce the database

and decision support software products that will

enable BFRL to identify its customers by SIC

categories, measure the customers' contributions

to GDP, measure the impact of BFRL's research

on GDP and employment by region of the U.S.,

and to evaluate and measure the impact of new

research opportunities to determine those with

the greatest likely national and regional

economic impact.

Recent Resuhs

Chapman, Robert and Fuller, Sieglinda, Benefits

and Cost of Research: Two Case Studies in Building

Technology, NISTIR5840, National Institute of

Standards and Technology, 1996.

Chapman, Robert and Weber, Stephen, Benefits

and Costs of Research : A Case Study of tJie Fire

Safety Evaluation System, NISTIR5863,

National Institute of Standards and

Technology, 1996.

A classification of typical benefits and costs

associated with scientific research is being

established to help researchers identify specific

benefits and costs of their research. The initial

classification will focus on building-related

research projects. This will help researchers and

managers think in economic impact terms when

planning projects and when evaluating them expost.

Three summary economic impact studies

performed in FY 1995 will be expanded and

206
Economics of New-Technology

Materials

Principal Investigator

Mark. Ehlen

Office of Applied Economics

301-975-4522

Sponsor

National Institute of Standards and Technology

Objective

To develop life-cycle economic methods for

evaluating the economics of substituting new

materials, such as composites or highperformance concrete and steel, for traditional

materials in civil engineering applications.

Problem

The construction industry needs sophisticated,

practical methods and guidelines for evaluating

alternative building materials in a consistent

manner over their life cycle. The need for

standardized, improved methods and guidelines

stems in part because high up-front costs of

new-technology construction materials

discourage their application even when

warranted by life-cycle criteria. Providing a method for evaluating life-cycle cost

effectiveness will give decision makers a tool to

help them select, both for research and

applications on the job, those materials that will

deliver the nation's infrastructure at least cost.

Approach

During FY 1996, staff will develop and publish

a report that will help analysts evaluate the cost

effectiveness of new materials in typical

construction applications such as bridge

building. A case study will evaluate composites

in comparison to conventional materials in the

construction of bridge decks. An initial

prototype of decision-support software will be

prepared to help state and Federal Department

of Transportation officials choose cost-effective

materials when issuing construction specifications for the construction and repair of bridges.

To disseminate the evaluation method

presented in the report, at least one technical

presentation will be given to potential users and

a technical article will be prepared for a refereed

journal.

In subsequent years, additional methods, such

as the adjusted internal rate of return and net

savings methods, will be developed. Techniques

for taking into consideration economic

uncertainty and risk will be explored. A multicriteria decision method that allows users to

simultaneously evaluate multiple economic and

engineering criteria when choosing among

alternative materials also will be developed.

Through participation in the ASTM Building

Economics Subcommittee (E06.81), efforts will

be made to have these methods and techniques

consistent with existing and future ASTM

building economics standards. Case studies

using these methods and techniques will be

prepared for both new (e.g., high-performance

concrete) and conventional materials competing

for use in bridge decks and in other applications

such as high-performance building systems.

Decision support software will be developed to

implement the methods and techniques for

multiple construction applications.

This three-year project supports the CONMAT

Implementation Plan concerning Life-Cycle

Cost Analysis. It also supports the National

Construction Goals by promoting reductions in

project delivery time and providing enhanced

durability.

Recent Results

Ehlen, Mark and Marshall, Harold, Tlte

Economics ofNew-Technology Materials in

Construction: A Case Stitdy ofFRP Composite

Bridge Decking, NISTIR5864, National Institute

of Standards and Technology, 1996.

207
Optimal Pricing of Standard

Reference Materials

Principal Investigator

Sieglinde I<L Fuller

Office of Applied Economics

301-975-6134

Sponsor

National Institute of Standards and Technology

Objective

To provide the Standard Reference Materials

Program (SRMP) with an optimal pricing

model, based on an analysis of demand for

SRMs, and subject to the constraint of having

to cover the cost of the program.

Problem

Since the early 1980's, NIST, like other

government agencies, has been increasingly

under pressure to recover the total cost of their

services through user fees rather than through

tax appropriations. The required changes in the

pricing policies of the SRMP have resulted in

higher prices for SRMs. From the observed

changes in aggregate unit sales and total revenues it is not clear whether or how the price

changes have affected the demand for SRMs,

given that other factors may affect demand. To

formulate pricing rules that cover the cost of the

program and do not adversely affect sales of

SRMs, it is imperative to include demand-side

information besides cost and supply

considerations.

Approach

During FY 1996, BFRLwdll perform four tasks:

1. Explain the theoretical model and its relationship to intermediate goods such as NIST SRMs.

2. Derive the optimal pricing formula for

SRMs.

3. Test the model with two SRMs to develop

the algorithms for subsequently

implementing the model for the 24 SRMs

for which the demand analyses have been

completed.

4. Draft a report describing the SRM model

and the results of the two-SRM test.

Public-sector economic theory provides an

operative optimization model for calculating

welfare-maximizing prices and outputs for

government enterprises that supply multiple

goods and services to users that can be

identified and charged fees. This model will be

adapted to intermediate goods and

implemented for SRMs. As the first step,

demand functions were derived for a selected

group of SRMs. The resulting price elasticities

of demand, which estimate the response of unit

sales to price changes, will be combined with

cost data to determine optimal prices and

saleable quantities. The research will estimate

the welfare gain from the optimal pricing rule

compared with alternative pricing formulas and

make recommendations to support SRMP

pricing policy in funding and sales negotiations.

Recent Results

In FY 1995 demand functions and price

elasticities were developed for 24 SRMs.

208
Baseline Measures for National

Construction Goals

Principal Investigator

Robert Chapman

Office of Applied Economics

301-975-2723

Sponsor

National Institute of Standards and Technology

Objective

To support the Subcommittee on Construction

and Building (C&JB), a part of the National

Science and Technology Council, identify

baseline measurement data of current practice

with respect to two committee thrusts

important to advancing the U.S. construction

industry: 1. improving the life cycle of

constructed facilities; and 2. improving health

and safety of the construction workforce.

Problem

The two priority thrusts specify the following

goals to be attained by the year 2002:

Better constructed facilities:

• 50 percent reduction in delivery time

• 50 percent reduction in operation and

maintenance

• 30 percent increase in productivity and

comfort

• 50 percent fewer occupant-related illnesses

and injuries

• 50 percent less waste and pollution

• 50 percent more durability and flexibility

Health and Safety of the Construction

Workforce

• 50 percent reduction in related illnesses and

injuries.

Data describing current practices of U.S. firms

with respect to the identified goals (e.g., 50%

reduction in delivery time) are needed to

establish a baseline against which to measure

progress of the construction industry toward

achieving these goals. It is essential to have

baseline data and associated measures of

progress toward improved performance to

determine the success of actions taken to

improve the competitiveness of the construction

industry in U.S. and international markets.

Having these measures of progress will make it possible to demonstrate the benefits of

advanced technologies and practices.

Approach

During FY 1996, BFRL staff will collect data on

current industry performance of the seven listed

goals. This work will be part of a collaborative

effort including other government agencies such

as the Bureau of the Census and the

Occupational Safety and Health Administration, private-sector organizations, and academic

institutions. These data on industry

performance will become the baselines for

measuring progress toward the achievement of

the identified percent reduction goals. The data

will be delivered initially as tables and reports.

They will be ultimately expanded into

computerized delivery systems available on the

Internet.

A start will be made this year on developing

methods for measuring progress. In subsequent

years these methods will be applied to the

measurement of progress toward the seven above goals. The methods will be made

available on the Internet. User-friendly decision

support software also will be developed to access baseline data and to measure progress

toward goals.

Recent Results

New project

209
Building for Environmental and

Economic Sustainability (BEES)

Principal Investigator

Barbara C. Lippiatt

Office of Applied Economics

301-975-6133

Sponsor

National Institute of Standards and Technology

Objective

To develop decision-support software for

selecting building materials that achieve the

most appropriate balance between life-cycle

environmental and economic performance

(second year of a 3 -year project).

Problem

Environmental and economic performances are two key factors in building material selection

decisions. The environmental performance of

building materials, however, is not readily

assessable and comparable to economic performance. A methodology is needed for assessing

and comparing environmental against economic

performance. To maximize technology transfer,

the methodology needs to be implemented in

publicly-available, user-friendly, decisionsupport software.

Approach

During FY 1996, BFRL staff will continue

developing the methodology for assessing and

comparing environmental against economic

performance. It is assessing the environmental

performance of building materials based on the

concept of life-cycle assessment, an analysis of

environmental impacts from raw materials

extraction to ultimate material reuse, recycling, or disposal. BFRL contracted for collection of

environmental performance data for five

building materials for the BEES system

(Building for Environmental and Economic

Sustainability). BFRL will continue to assess economic performance using the life-cycle

costing concept, and collect life-cycle cost data

from the five materials. An Alpha version of the

BEES system is being developed.

In FY 1997, BFRL will add five more building

materials to the BEES systems and conduct a Beta test of the BEES software. The Beta test comments wdll be incorporated in a final review

version of the BEES software and user manual.

Finally, BFRL will continue its active

participation in ASTM E50.06 (Green

Buildings), and draft an ASTM document for

ASTM E06.81 (Building Economics) illustrating

how Multi-Attribute Decision Analysis can be

used in life-cycle assessment.

Recent Results

Lippiatt, B.C. and Norris, G.A., "Selecting

Environmentally and Economically Balanced

Building Materials," Second International Green

Building Conference and Exposition -- 1995, NIST

Special Publication 888, National Institute of

Standards and Technology, pp. 38-46, 1995.

Lippiatt, B.C. and Norris, G.A., "Selecting

Environmentally and Economically Balanced

Building Materials," reprinted in, Sustainable

Building Technical Manual: Green Building Design,

Construction, and Operations, Florida A&M

University, 1996.

210
Life-Cycle Costing Methodology

Principal Investigator

Stephen R. Petersen

Office of Applied Econonnics

301-975-6136

Sponsor

National Institute of Standards and Technology

U.S. Department of Energy

Federal Energy management Program

Objective

To provide on a continuing basis, economic

analysis methods, data, software, training, and

consulting to the DOE's Federal Energy

Management Program in support of energy and

water conservation projects in federal buildings

and facilities.

Problem

The National Energy Conservation Policy Act

directs NIST to provide expert consulting to

DOE related to econorruc analysis of energy

conservation projects in federal buildings.

Executive Order 12902 of 8 March 1994,

requires that energy usage in federal facilities be

reduced by 30 percent by the year 2005

compared with 1985 levels, in a cost-effective

manner.

Approach

During FY 1996, BFRL will provide, on a continuing basis, economic analysis methods,

data, software, training, and consulting. BFRL is responsible for assisting DOE develop and

modify FEMP LCC rules as promulgated in 10

CFR 436 Subpart A. BFRL is amplifying these

rules and procedures in NIST Handbook 135,

Life-Cycle Costing Manualfor the Federal Energy

Management Program .

f

Annually, BFRL computes the discount rate to

be used in the analysis of federal energy and

water conservation projects, using the procedure

specified in 10 CFR 436. In addition, staff compute tables of discount factors and energy price

indices based on this discount rate and on

energy price projections received from

DOE/ELA. These data are published each

October 1 in the Annual Supplement to Handbook

135, and included in electronic form with

BFRL's LCC software.

BFRL developed five computer programs for

economic analysis of energy and water

conservation projects: BLCC, Quick Input,

DISCOUNT, ERATES, and EMISS. These

programs are maintained, updated, and

enhanced with new analytical capabilities

annually. DOE and private-sector software

vendors distribute these programs. User

manuals are provided with each program. The

software also has been incorporated into several

other software projects outside NIST, sponsored

by DOE.

BFRL developed a basic LCC workshop which it has conducted five times each year at locations

throughout the United States, primarily for

federal engineers and energy managers, but

attended by representatives from state and local

government, utilities, and consultants from the

private sector. In FY 1996, staff will be

developing and teaching an advanced LCC

workshop that is more oriented toward project

analysis and the OAE LCC software. BFRL has

trained 22 instructors, mostly university

professors and private consultants, to conduct

the basic LCC workshop, and is providing them

required teaching materials. These trainers are now conducting many additional workshops

throughout the United States, greatly

expanding the reach of BFRL research activities.

Staff have developed three LCC training videos

with workbooks to promote the use of economic

analysis in project design and maintenance.

BFRL provides consulting to DOE related to

methods of economic analysis for federal energy

and water conservation projects on a continuous basis. For example, changes to the

FEMP LCC rules in 10 CFR 436 are made in

consultation with OAE; users of BFRL publications and software frequently call with technical

questions related to these materials and to

interpretation of 10 CFR 436; and Staff are working with FEMP to reconcile differences in

DOD's LCC methodology with the FEMP

methodology used by other federal agencies.

211
Recent Results

Fuller, Sieglinda, and Petersen, Stephen, LifeCycle Costing Manualfor the Federal Energy

Management Program , NIST Handbook 135,

National Institute of Standards and

Technology, February 1996.

Petersen, Stephen R., BLCC- The NIST

"Building Life-Cycle Cost" Program, Version 4.3

User's Guide and Reference Manual, NISTIR

5185-3, National Institute of Standards and

Technology, October 1995.

Petersen, Stephen R., EMISS- A Program for

Estimating Local Air Pollution Emission Factors

Related to Energy Use in Buildings User's Guide and

Reference Manual, NISTIR 5704, National

Institute of Standards and Technology, October

1995.

Fuller, Sieglinde K., and Petersen, Stephen R.,

Life-Cycle Costing Workshop for Energy Conservation

in Buildings: Student Manual, NISTIR 5 165,

National Institute of Standards and

Technology, October 1995.

Petersen, Stephen R., Energy Price Indices and

Discount Factors for Life-Cycle Cost Analysis 1996:

Annual Supplement to NIST Handbook 135 and

NBS Special Publications 709, NISTIR 85-3273-

10, National Institute of Standards and

Technology, October 1995.

Petersen, Stephen R., Present Worth Factors for

Life-Cycle Cost Studies in the Department of Defense

(1996), NISTIR 4942-3, National Institute of

Standards and Technology, October 1995.

Provide Economic Support to NIST

Manufacturing Extension

Partnership

Principal Investigator

Stephen F. Weber

Office of Applied Economics

301-975-6137

Sponsor

National Institute of Standards and Technology

Objective

To support the economic and program

evaluation missions of MEP by identifying

economic data sources, developing economic

data analysis software, developing economic

maps, and modeling economic impacts.

Problem

MEP management needs economic consulting

support for planning, reporting, and program

evaluation.

Approach

During FY 1996, BFRL will assist the NIST

Manufacturing Engineering Program (MEP) in

developing survey questions to capture data on

the direct economic impacts at the individual

establishment level resulting from Technical

Assistance Projects (TAPs) of Manufacturing

Extension Centers (MFCs). BFRL will develop

methods and obtain supporting data to derive

industry level shock variables compatible with

the REMI economic impact simulation model.

BFRL will obtain preliminary data from MEP

and conduct test analyses of MEP impacts using

REMI model. Once sufficient survey data are

available, staff will conduct REMI analysis and

interpret the results.

Staff wall also implement the application of

Data Envelopment Analysis (DEA) to measure

and suggest improvements in the relative

efficiency of MFCs. BFRL will work with MEP

to identify the best input , output, and control

variables to use in the DEA analysis. Staff will

complete a working version of the DEA Excel

software. Once data are collected by MEP, staff

will apply the DEA software to the data and

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report the results to MEP.

BFRL also wiW support MEP by providing

economic data and maps to define the scope,

scale, and geographic distribution of

manufacturing establishments and

Manufacturing Extension Centers (MECs).

Recent Results

Identified and successfully procured REMI

economic forecasting and simulation software.

Developed prototype Excel programs to test the

application of DEA analysis.

Developed economic maps showing small

manufacturing industry concentrations and the

coverage by county of all MTCs in the MEP

system.

Economic Support for the Office of

Law Enforcement Standards

Principal Investigator

Stephen F. Weber

Office of Applied Economics

301-975-6137

Sponsor

National Institute of Standards and Technology

Objective

To update and publish AutoBid software to

support police vehicle acquisition decisions.

Problem

AutoBid software that supports police vehicle

acquisition decisions needs to be updated to

include the latest 1996 model year data on

police vehicle performance. The current version

of AutoBid is directly dependent on a specific

set of data files that each cover one vehicle

model year. The data files contain the

performance test results for police patrol

vehicles published annually by the Michigan

State Police. The specific data files expected to

be present are explicitly referenced in the source code of the software. This feature requires that

the source code be modified each year when the

new model year data become available. As a

result, the entire program must be recompiled

each year.

Approach

During FY 1996, BFRL will assist NIST's Office

of Law Enforcement Standards in preparing the

data files compatible with AutoBid for the

1996 model year. BFRL will begin work on

redesigning the software to recognize

automatically any vehicle model year data files

in the current directory and give the user a menu to select any given year for which the

data are present.

Recent Results

Weber, Stephen E., AutoBid 2.0: Tiie

Microcomputer System for Police Patrol Vehicle

Selection, NISTIR5787, National Institute of

Standards and Technology, February 1996.

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Decision Support Software for

Hospitals Financed by HUDGuaranteed Loans

Principal Investigator

Stephen F. Weber

Office of Applied Economics

301-975-6137

Sponsor

U.S. Department of Health and Human

Services

Health Resources and Services Administration

Objective

To develop a comprehensive decision support

software system for the hospitals and health

care facilities financed by HUD-guaranteed

loans.

Problem

The Division of Facilities and Loans of the

Health Resources and Services Administration

(HRSA) manages a large portfolio of HUDguaranteed loans made to hospitals and health

care facilities. Existing software is used solely for

manual recording and reporting on the status of

outstanding loans and does not support

optimization of decisions on operation,

maintenance, repair, and expansion

expenditures over the life cycle of the facilities.

Moreover, the system is not integrated with

other critical HUD data about the current

condition of the hospital facilities themselves.

The source code is unavailable, so that the

software cannot be modified or updated. HRSA

sponsors need a new system that can access all relevant data to support critical decisions, such

as when to survey hospitals for compliance with

the Life Safety Code, when an energy

conservation audit is advisable, and whether to

renew or refinance a loan because of the

facility's operation and maintenance

performance.

Approach

During FY 1996, (first phase of this project)

BFRL will first evaluate the existing software

and interview users to specify data elements and

user requirements in terms of functions and

reports. BFRL also will review all HUD data

used for supporting operation, maintenance,

repair, and expansion decisions about the

facilities. A draft data dictionary of all files and

data fields will be developed and a summary of user requirements produced. It will be

submitted for approval by HRSA sponsors. A

prototype of the system then will be developed.

Once the prototype software is approved by

HRSA, a working test version of the data entry

and modules reviewed. A standardized report

module for the monthly Loan Status Manual

will be developed. After the test version of the

software has been evaluated by HRSA, BFRL

will revise it per comments and integrate the

report module into it. Finally, the software will

be delivered to HRSA, installed, and import the

existing data into the new software.

During Phase 2, BFRL will participate in a study to determine the appropriateness and

feasibility of read-only remote access to the data

by HUD Hospital Mortgage Insurance Staff as a substitute for the existing centrally printed

quarterly reports. Such access at the local level

will make possible more cost-effective decisions

about the health care facilities. Phase 3 will

involve development of the necessary modules

to permit customized, user-defined queries of

the data. We will also develop decision support

modules to guide actions on major expenditures

for repairs, renovations, and expansions of the

health care facilities.

Recent Results

New project

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Economic Support for BFRL

Principal Investigator

Harold E. Marshall

Office of Applied Economics

301-975-6131

Sponsor

National Institute of Standards and Technology

Objective

To implement the comprehensive plan for the

Office of Applied Economics's (OAE) support of

BFRL's goals and contribute to the revision of

old and development of new standard economic

methods, guides, and classifications to help the

national and international building

communities evaluate new technologies and

achieve affordable buildings that meet

performance objectives.

Problem

The building community needs sophisticated,

practical methods and guidelines for evaluating

alternative building technologies in a consistent

manner. The need for standardized, improved

methods and guidelines stems in large part from

the high costs of building materials, the high

costs of construction due to

safety/environmental regulations, the alleged

slow growth in construction productivity, the

uncertain costs of energy, and the uncertain life- cycle costs associated with new technologies.

Approach

During FY 1996, OAE will update and

implement the comprehensive plan/vision for

economic analysis in support of BFRL's goals.

The plan includes a vision, values, mission, and

goals for OAE in support of BFRL and NIST. It includes proposed projects such as standard

methods for measuring the cost effectiveness of

new technologies (for example, composite

materials); standard methods and supporting

computer programs for promulgation through

ASTM (multi attribute decision analysis

standard and software); support to the National

Science and Technology Council's

Subcommittee on Construction and Buildings

(C&JB); and recruitment targets and staff

assignments to achieve the plan.

Economic methods and supporting analyses will

be specially developed for application to

building problems. The principal avenues for

transferring them to the building community

will be the ASTM Building Economics Subcommittee, the C&JB Subcommittee, and the CIB

Building Economics Working Commission. For

the latter, technical and administrative support

will be provided CIB's Working Commission

through continuing work on the Spon book on

project evaluation. It will be the first volume of

the CIB-sponsored Building Economics Reader

Series.

Administrative and technical leadership wall be

provided the ASTM Subcommittee. In FY

1996, the major technical effort will be

completing the successful balloting of a new

standard method for multi attribute decision

analysis (MADA) and developing models of

building and materials applications for use in an

ASTM Software Product being developed to

support the standard. OAE will continue to

chair the Building Economics Subcommittee

and perform technical work that contributes to

new and revised standards.

Recent Results

Norris, Gregory A., and Marshall, Harold E., Multi attribute Decision Analysis Methodfor

Evaluating Buildings and Systems, NISTIR5663,

National Institute of Standards and

Technology, September 1995.

Marshall, Harold E., Least-Cost Energy Decisions

for Buildings - Part III: Choosing Economic

Evaluation Methods Video Training Workbook,

NISTIR5604, National Institute of Standards

and Technology, May 1995.

Marshall, Harold E., "Roundtable on a Standard Method for Value Engineering: AACE

International Annual Meeting June 2 1, 1994,"

Cost Engineering, Vol. 37, No. 3, pp. 9-21,

March 1995.

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