AlllDl TMblflb

NAFL INST OF STANDARDS & TECH R.I.C. NBS

OBLIGATIONS

1982 - 1983

BUILDING

TECHNOLOGY

PROJECT

SUMMARIES

^7.5". Department of Commerce

National Bureau of Standards

Special Publication 44(^-7

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Wo

1983

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OF STANDARDS

LIBRARY g^p 8 1983

1982 - 1983

BUILDING

TECHNOLOGY

PROJECT

SUMMARIES

(Vlt^S Special Publication 446-7

Editors

Noel Raufaste

Michael Olmert

Center for Building Technology

National Engineering Laboratory

National Bureau of Standards

U.S. Department of Commerce

Washington, DC 20234

Issued June 1983

U.S. DEPARTMENT OF COMMERCE, Malcolm Baldrige, Secretary

NATIONAL BUREAU OF STANDARDS, Ernest Ambler, Director
National Bureau of Standards Special Publication 446-7

Natl. Bur. Stand. (U.S.), Spec. Publ. 446-7, 138 pages (June 1983)

CODEN: XNBSAV

U.S. GOVERNMENT PRINTING OFFICE

WASHINGTON: 1983
FOREWORD

The building research program of the National Bureau of Standards, the Nation's central

engineering measurements laboratory, is conducted by its Center for Building Technology (CBT). CBT

performs field, laboratory, and analytical research to provide knowledge on the properties of whole

buildings and building materials, components, and systems, and on measurement techniques to evaluate

these properties. This knowledge is needed for responsible and cost-effective decisions on the

building process and cannot be obtained through proprietary research and development.

Construction is one of the Nation's largest industries. It amounted to about $238 billion,

8 percent of the GNP , in 1982. Sixty-nine percent of the Nation's wealth, $5,300 billion, is invested

in constructed facilities that shelter and support almost all human activities. Effective building

decisions require sound technical bases. CBT is the only comprehensive, non-proprietary laboratory in

the U.S. dedicated to meeting the measurement needs of the building community. The term "building

community" describes the groups responsible for the design, construction, and operation of constructed

facilities. These include owners, manufacturers, designers, financiers, developers, contractors,

craftsmen and laborers, educators, research and testing laboratories, standards developing organizations, and regulatory agencies of state and local governments.

CBT research provides knowledge for decisionmaking. This knowledge includes characterization of

the environments in which buildings must operate (such as snow loadings to be anticipated during the

service life), characterization and definition of the performance of buildings, components, and systems (such as the mechanisms for heat loss through a window or wall cladding element), and methods of

testing for performance qualities that will apply equitably to a whole family of potentially

competitive proprietary materials and components.

The CBT staff of 150 includes 100 professionals, of whom 3^ afe registered professional engineers

or architects and 50 hold the Ph.D. degree. The principal disciplines are structural, geotechnical

,

materials, electrical and mechanical engineering, physics, and chemistry.

The Center's specialized laboratory facilities and equipment located at Gaithersburg , Maryland,

have a replacement value estimated at $20 million. Among the variety of special facilities and equipment are the universal testing machine with a 1 2-raillion-pound capacity; a reaction wall for subjecting full-scale building systems to earthquake loading; seven environmental chambers, including a 30 x

40 X 60 ft chamber, for evaluating the thermal performance of buildings and components; a line heat

source guarded hot-plate to characterize insulation to 12 inches thick; a calibrated hot-box test

facility; a five-story plumbing research laboratory; reverberation and anechoic chambers; lighting

iii
research facilities; mobile laboratories; an outdoor solar-collector test-method development area,

including a passive solar test house; a network of outdoor exposure sites; a scanning electron microscope and other instruments for material characterization; facilities for experiments on solar heating

and cooling systems; and controls and equipment laboratories.

This report summarizes CBT's research for 1982-1933- Each summary lists the project title, its

progress, point of contact within CBT, and sponsor. The summaries are arranged according to the

research areas that cover the scope of work at CBT. The reader is encouraged to review a companion

document: NBS Special Publication 457, Building Technology Publications , and its supplements. Final

reports on the projects described here will be listed in future issues of that document.

iv
CONTENTS

Page

Structural Engineering Criteria for Structural Loads and Design 2

Criteria for Design of Cladding Subjected to Wind Loads 3 Criteria for Wind Tunnel Modeling 4 Dependence of Extreme Wind Speed Upon Direction 5 Probabilistic Risk Assessments of Tornado Missile

Damage 6 Reliability-Based Design of Containments and Category

I Structures 7 Dynamics and Reliability of Compliant Drilling and

Production Platforms 8

Assessment of the Uncertainties and Risk Associated with

the Dynamic Behavior of Compliant Offshore Structures 9

Geotechnical Engineering Geotechnical Measurement of In-Situ Soil Properties 11 In-Situ Measurement of Soil Properties by Thermal Methods 12

In-Situ Measurement of Soil Properties by Acoustics 13 Cyclic Strain Approach to the Determination of Liquefaction

Potential of Level Sandy Sites 14

Gage for Measurement of Dynamic Soil Stress 15

Earthquake Engineering Technical Assessment of Earthquake-Resistant Design

Provisions 17

Torsional Effects in Buildings Subjected to Earthquake

Excitations 18

Fatigue Tests in Full-Scale Block Walls 19 Large-Scale Bridge Columns Subjected to Reversed Cyclic

Loading 20

Cyclic Loading of Masonry Building Components 21

Construction Engineering Construction Load Effects 23

Structural Condition Assessment Standards 24

Sonic-Pulse-Echo Inspection of Concrete 25

Performance of Concrete Structures in the Arctic 26

Safety in Concrete Construction 27

Development of Safety-Net Standards for Construction 28

Service-Life Prediction Application of Life-Test Analysis Concepts to Building

Materials 30

Cement Hydration 31

Performance of Concretes 32

Short-Terra Evaluation Procedures of Coatings for Steel 33

Corrosion of Steel in Prestressed Concrete 34

Organic Coatings 35

Characterization of Blister Growth and Corrosion Under

Protective Organic Coatings 36

Corrosion and Weathering Data 37

Corrosion of Aluminum Roofing 38

Evaluation of Single-Ply Roofing Systems 39

Performance of Bonded Seams in Single-Ply Roofing Membranes .... 40

Performance of Residential Siding 41

Tri-Services Technical and Scientific Support 42

Guide Specifications for High-Performance Latex Paints 43

Standards for High-Security Glazing Materials 44

Solar Collector Durability and Reliability Test Program 45

Standards for Solar Absorptive Coatings 46

Environmental Degradation of Polymeric Cover Materials for

Solar Collectors 47

Evaluation of Optical Techniques for Measuring Absorber

Materials Degradation ,. 48

Degradation of Heat Transfer Fluids in Solar Heating

Systems 49

V
CONTENTS (Continued)

Pagg

Service - Life Prediction Documentation of Materials Research Data and Activities 50

(Cont.) ' Performance Criteria for Solar Systems in Commercial

Buildings 51

Residential Solar Data Center 52

Solar Energy International Cooperation , 53

Buffers for Glycol-Based Heat Transfer Fluids 54

Quality Assurance NOE of Building Materials 56

Security Barriers 57

Development of Tests for Predicting Adhesive Bond Durability ... 58

Laboratory Accreditation: Solar Collector Testing 59

AASHTO Materials Reference Laboratory (AMRL) 60

Cement and Concrete Reference Laboratory (CCRL) 61

Criteria and Standards standards interface for Coraputer-Aided Structural Design 63

Representation and Analysis of Construction Standards and

Specifications 64

Format for Model Building Codes 65

Documentation and Assessment of PBS Building Systems Program ... 66

Office Automation Impact on Interior Environments 6?

Economic Methods for Building Standards 68

Development of Solar Regulatory System 69

Thermal Insulation Thermal Analysis and Modeling 71

Calibrated Hot-Box Measurements 72

Guarded Hot Plate and Heat-Flow Meter 73

Thermal Performance Field Measurements of Wall Thermal Mass 75

Multi-Room Thermal Modeling 76

Underground Heat Distribution Systems 77

Earth Contact Heat-Transfer Modeling 78

Heat Loss Through Thermal Bridges 79

Energy Analysis for ASHRAE-90A Revision 80

Energy Analysis Procedures 8l

Air Infiltration in Large Buildings 82

Diagnostic Procedures for Federal Building Envelopes 83

Thermographic Mapping of Down Spouts in Treasury Building 84

Transient Performance of Building Defects 85

Laboratory Tests for Thermographic Standards 86

Energy Performance of Residences 87

Thermal Test Methods—Solar Collectors 38

Thermal Test Methods—Passive Components 89

Solar Hot Water Test Program , 90

Response of Radiometric Converters to Sky-Radiance

Distributions 91

Response of Radiometric Converters to Extended, Close

Sources 92

Building Acoustics and Acoustic Measurements for Buildings 94

Lighting Technology Prevention of Traffic-Noise Problems 95

Visual Criteria 96

Task-Lighting Criteria 97

Illumination System Measurements 98

Optimized Model for Brightness 99

New Definition of Photometry 100

High-Efficiency Lights and Chromatic Response 101

Opponent-Colors Approach to Color Appearance 102

Daylighting Studies 103

CEL-1 Lighting Program 104

The Use of Hazard Pictorials/Symbols in Mines 105

Hazard Pictorial Signage for Sand and Gravel and Crushed

Stone Mines 106

vi
CONTENTS (Continued)

Pass.

Building Thermal Equipment Evaluating the Performance of Heat Pumps 108

Heat Pump and Air Conditioner Test Procedures 109

Examination of Non-Azeotropic Mixture Refrigerants for

Heat Pumps 110

Refrigerant Mixture Measurements in Two-Phase Flow Ill

Refrigerator and Freezer Studies 112

Water Heater Studies 113

Furnace, Boiler, and Household Appliance Test Procedures ....... 114

Appliance Standards 115

Household Appliance Data Update 116

Thermal Test Methods — Solar Assisted Heat Pumps and

Cooling Components and Systems 117

Experimental Evaluation — Solar Test Cells 118

Technical Support to DoE 119

Mechanical Systems and Systems and Controls Laboratory 121

Controls Controls Dynamic Modeling 122

Energy Monitoring and Control System Measured Performance 123

Energy Analysis of Control Strategies 124

Energy Monitoring and Control System Algorithms 125

Unsteady Hydraulics of Branch Drains and Soil Stacks . . . . , 126

Air Quality Criteria for Archival Storage 127

Existing Building Wiring Systems 128

vii
ABBREVIATIONS

AASHTO American Association of State Highway and Transportation Officials

ABBE Advisory Board on the Built Environment

ACI American Concrete Institute

AIA American Institute of Architects

AMRL AASHTO Materials Reference Laboratory

ANSI American National Standards Institute

ARI Air-Conditioning and Refrigeration Institute

ASCE American Society of Civil Engineers

ASSE American Society of Sanitary Engineers

ASTM American Society for Testing and Materials

ASHRAE American Society for Heating, Refrigerating, and Air-Conditioning Engineers

ASME American Society for Mechanical Engineers

BECC Building Energy Conservation Criteria

BEPS Building Energy Performance Standards

BLAST A Computer Program Dealing with Building Energy Loads

BNL Brookhaven National Laboratory

BOCA Building Officials and Code Administrators International, Inc.

BOM Bureau of Mines

BSS Building Science Series

BUR Built-up Roofing

CABO Council of American Building Officials

CAD Coraputer-Aided Design

CBT Center for Building Technology

CCC Codes Community Committee

CERL Construction Engineering Research Laboratory (U.S. Army)

CIS International Council for Building Research, Studies, and Documentation

CICC Construction Industries Coordinating Committee

CIE International Commission on Illumination

CSA Community Services Administration

CPSC Consumer Product Safety Commission

DoD Department of Defense

DoE Department of Energy

EIA Energy Information Agency

EMCS Energy Monitoring and Control Systems

EPA Environmental Protection Agency

FAA Federal Aviation Administration

FCC Federal Construction Council

FEMA Federal Emergency Management Agency

FERC Federal Energy Regulatory Commission

FHWA Federal Highway Administration

FPL Forest Products Laboratory

GSA General Services Administration

HHS Department of Health and Human Services

HUD Department of Housing and Urban Development

HVAC Heating, Ventilating, and Air-Conditioning

ICBO International Conference of Building Officials

IEEE Institute of Electrical and Electronic Engineers

lERI Illuminating Engineering Research Institute

lES Illuminating Engineering Society

lESNA Illuminating Engineering Society of North America

ISO International Standards Organization

LANL Los Alamos National Laboratory

LBL Lawrence Berkeley Laboratory

NAHB National Association of Home Builders

NBS National Bureau of Standards

NBSIR National Bureau of Standards Interagency Report

NBSLD National Bureau of Standards Load Determination (A Computer Program)

NCSBCS National Conference of States on Building Codes and Standards

NDE Nondestructive Evaluation

NIBS National Institute of Building Sciences

NIOSH National Institute of Occupational Safety and Health

NML National Measurement Laboratory

viii
NOAA National Oceanic and Atmospheric Administration

NPS National Park Service

NRC Nuclear Regulatory Commission

NRCC National Research Council (Canada)

NSF National Science Foundation

ORNL Oak Ridge National Laboratory

OSHA Occupational Safety and Health Administration

PBS Public Buildings Service

PBS/BSP PBS Building Systems Program

PMMA Polymethylmethacrylate

PVC Polyvinyl Chloride

RILEM International Union of Testing and Research Laboratories for Materials and

Structures

RSV Reduced-Size Venting

SAE Society of Automotive Engineers

SASE Standards Analysis, Synthesis, and Expression Software

SERI Solar Energy Research Institute

SPT Standard Penetration Tests

SRM Standard Reference Materials

UBC Uniform Building Code

USGS United States Geological Survey

USNC/CIB United States National Committee/International Council for Building Research,

Studies, and Documentation

VA Veterans Administration

CENTER FOR BUILDING TECHNOLOGY

CENTER HEADQUARTERS

I

STRUCTURES

DIVISION

BUILDING

MATERIALS

DIVISION

BUILDING

PHYSICS

DIVISION

BUILDING

EQUIPMENT

DIVISION

• Structural Engineering -Organic Materials

• Geotechnical Engineering • Inorganic Materials

• Earthquake Hazard • Cement Hydration

Reduction • Materials Reference

• Construction Safety Laboratories

• Thermal Analysis

• Thermal Measurements

• Thermal Insulation

• Acoustics

• Ilium ination Engineering

• Thermal Machinery

• Mechanical Systems

and Controls

• Combustion Equipment

• Solar Equipment

ix

STRUCTURAL

ENGINEERING

Criteria for Structural Loads and Design

Criteria for Design of Cladding Subjected to Wind Loads

Criteria for Wind Tunnel Modeling

Dependence of Extreme Wind Speed Upon Direction

Probabilistic Risk Assessments of Tornado Missile Damage

Reliability-Based Design of Containments and Category I Structures

Dynamics and Reliability of Compliant Drilling and Production Platforms

Assessment of the Uncertainties and Risk Associated with the Dynamic

Behavior of Compliant Offshore Structures

1
CRITERIA FOR STRUCTURAL LOADS AND DESIGN

Bruce Ellingwood

(301) 921-3471

Structures Division

Sponsor: National Bureau of Standards

Current structural design standards rely on different philosophies and

criteria for design, depending on the material or construction technology

used. This tends to complicate design when different technologies are

employed in the same structure. Differences in design philosophy cause a

lack of consistency in the reliability levels of different buildings. In

recognition of these problems, the trend in Europe and Canada has been toward

the development of a common basis for design that would be applicable to all

buildings regardless of their material or construction technology. To ensure

adequate performance, the unifying concept of limit states has been used,

along with a probabilistic treatment of the uncertainties invariably found

in engineering design.

This project is concerned with developing design criteria for use in

building standards that will ensure adequate reliability against structural

failure and unserviceability . This will lead to reduced building costs by

simplifying the design process and stimulating market competition between

construction technologies. Improved serviceability requirements would result

in less maintenance and increased occupant satisfaction. This research will

be valuable to national standards organizations and to Federal agencies

charged with developing criteria for reliability and serviceability of building structures. These include the HUD Minimum Property Standards and ANSI A58

(Minimun Design Loads in Buildings and Other Structures).

2
CRITERIA FOR DESIGN OF CLADDING SUBJECTED TO WIND LOADS

Emil Simiu

(301) 921-3169

Structures Division

Sponsor: National Bureau of Standards

Modern analytical and experimental tools have not yet been used in

investigating the reliability of cladding subjected to wind loads. Tools froto

the fields of wind engineering (aerodynamics of oluff bodies in turbulent

boundary layer flows), nonlinear mechanics of plates, structural reliability,

and materials testing will be used in this project with a view to developing

rational criteria for cladding design. Data from full-scale and wind-tunnel

investigations of wind loads on cladding will be reviewed and studies will

be conducted to determine additional research needs.

This year, the project will develop an NSF proposal on glass behavior

under wind loads, and will compare failure statistics using empirical criteria

versus correct wind engineering approaches. Another output will be a study of

how fluctuating loads affect failure statistics. Successful completion of

this project could save money and reduce accidents that result from unsafe

cladding. Other savings could result by preventing the overdesign of cladding

in instances where conservative design provisions prevail.

3
CRITERIA FOR WIND TUNNEL MODELING

R.D. Marshall

(301) 921-2170

Structures Division

Sponsor: National Bureau of Standards

This project will support the development of operational criteria and

preliminary planning of aerodynamic and structural design of a CBT boundarylayer wind tunnel. Facility design will be based in part on test data obtained

from previous studies carried out on a 1/4-scale model of the proposed tunnel.

When completed, the tunnel will enable CBT to address important problems in

several areas of building technology. In addition to providing new opportunities for research, this facility will enable CBT to more effectively respond

to the research needs of Federal agencies such as DOE, FHWA, GSA, and HUD.

The recently published proceedings of the international wind tunnel workshop

held at NBS in April 1982 is expected to influence modeling techniques both

here and abroad

.

4
DEPENDENCE OF EXTREME WIND SPEED UPON DIRECTION

Emil Simiu

(301) 921-3169

Structures Division

Sponsor: National Science Foundation

Current procedures for estimating wind loads take into account the

dependence of aerodynamic coefficients upon the direction of the wind speeds.

However, no account is taken of the dependence upon direction of the extreme

wind speeds expected to act on the structure during its lifetime. For this

reason, reliability levels can vary significantly among wind-sensitive components of the same structure. In this project, a statistical procedure for

estimating wind loads that may be expected to act on structures during their

anticipated life will be developed, in which wind directionality effects will

be taken into account. The procedure consists of creating scalar time series

of the extreme wind pressures and inferring design wind speeds through

statistical analysis.

The procedure will be adopted for use in hurricane-prone regions, where

special statistical methods for describing the wind climate must be used.

Advantage will be taken of previous CBT experience with such methods. The

reliability of structures whose orientation is not known in advance will be

estimated by taking wind directionality into account, with a view to developing

procedures for developing risk-consistent code provisions for wind-sensitive

structures. Information on dependence of extreme winds upon direction obtained

by the National Climatic Center (NOAA) within the framework of this project

will be published for use by structural designers.

5
PROBABILISTIC RISK ASSESSMENTS OF TORNADO MISSILE DAMAGE

Emil Simiu

(301) 921-3169

Structures Division

Sponsor: Nuclear Regulatory Commission

Among the possible causes of damage to nuclear power plants is the impact

of objects, referred to as missiles, that are propelled by tornado winds. The

Nuclear Regulatory Commission specifies that the probability of tornado-borne

missiles attaining critical speeds and hitting nuclear power plants must not

exceed 10""^ in any one year. Whether or not this is the case, it should be

verified before the approval of any particular nuclear power plant. This

project is concerned with assessing a verification carried out by Bechtel

Corporation for the spray nozzles of the ultimate heat sink in the Palos Verde

Nuclear Generating Station, and the general methodology for estimating tornadoborne missile risks proposed in the report, "Tornado Missile Simulation and

Design Methodology." The assessment is carried out using probabilistic, statistical, and numerical simulation tools, as well as information concerning

frequency of occurrence and physical characteristics of tornadoes, and aerodynamic characteristics and potential number and location of objects susceptible of becoming tornado-borne. This work will assist NRC in ensuring

acceptably small risks of accident in the operation of nuclear power plants.

6
RELIABILITY-BASED DESIGN OF CONTAINMENTS AND CATEGORY I STRUCTURES

Bruce Ellingwood

(301) 921-3471

Structures Division

Sponsor: Brookhaven National Laboratory

The unpredictable nature of the possible loads on nuclear power

structures, as well as uncertainties in structural properties and behavior,

suggest a probabilistic approach for an assessment of structural safety and

performance. This means that safety and performance should be determined

according to acceptable levels of risk or required levels of reliability.

Structural reliability theory already has been applied to earthquake engineering, wind engineering, ocean engineering, aerospace structures, and in the

development of load factors, load combinations, and resistance factors for

practical design.

In the nuclear industry, there has also been an increasing trend toward

the use of statistical analysis and probability theory for safety evaluations.

This is particularly the case for seismic Category I structures for which

rational methods for reliability evaluation of strength and loads are urgently

needed. This new reliability-based design approach has a number of significant

advantages. It can be expected that structural designers and regulatory authorities will take advantage of these methods if they do not lead to significant

additional complexities at the design level.

Under this joint project, CBT will have responsibility for the analysis

of service and extreme environmental loads and for developing the basic load

combination methodology. BNL will have responsibility for analyzing accidential loads, postulating accident scenarios, dynamic structural analysis of the

nuclear structures, and testing the design procedure.

7
DYNAMICS AND RELIABILITY OF COMPLIANT DRILLING AND PRODUCTION PLATFORMS

Emil Siraiu

(301) 921-3169

Structures Division

Sponsor: United States Geological Survey

According to published estimates, costs of conventional fixed offshore

platforms are prohibitive in deeper waters, where compliant structures become

economically justified. These estimates indicate that guyed tower systems are

economical for water depths within the approximate range of 1,000 to 1,600 ft,

whereas the use of tension-leg platforms becomes economical for water depths

in excess of about 1,600 ft. Because the behavior of a compliant structure in

a marine environment is complex, the evaluation of its performance can pose

difficult problems to regulatory agencies. The purpose of this study is to

create a basis for understanding the behavior of complaint structures and

estimating their reliability during construction and service. The study will

include the gathering and evaluation of information on proposed designs, identification of topics needing research, and research on critical topics. The

results of this work will make possible the design of the most reliable and

cost-effective platforms possible.

8
ASSESSMENT OF THE UNCERTAINTIES AND RISKS ASSOCIATED WITH THE DYNAMIC BEHAVIOR

OF COMPLIANT OFFSHORE STRUCTUi^ES

Emil Simiu

(301) 921-3169

Structures Division

Sponsor: Minerals Management Service

The purpose of this study is to employ information on various proposed

designs to list limit states that may occur as a result of the dynamic behavior

of compliant offshore structures, and apply modern structural reliability

techniques to the estimation of nominal failure probabilities of such structures and the assessment of their structural safety. For selected compliant

offshore structural types, this project will provide detailed mathematical

models of the limit states that may occur as a result of their dynamic behavior

under wind and wave action.

Researchers will review fundamentals, practical methodologies, and

computer programs pertaining to structural reliability, will obtain suitable

computer programs for estimation of failure risk based on Monte Carlo simulations, and maintain close contact with the American Bureau of Shipping, Det

Norske Veritas, Navy Department, and other agencies with an interest in

structural reliability of compliant offshore structures.

9
GEOTECHNICAL

ENGINEERING

Geotechnical Measurement of In-Situ Soil Properties

In-Situ Measurement of Soil Properties by Thermal Methods

In-Situ Measurement of Soil Properties by Acoustics

Cyclic Strain Approach to the Determination of Liquefaction Potential of Level

Sandy Sites

Gage for Measurement of Dynamic Soil Stress

10
GEOTECHNICAL MEASUREMENT OF IN-SITU SOIL PROPERTIES

William D. Kovacs

(301) 921-2648

Structures Division

Sponsor: National Bureau of Standards

The key to ensuring the stability of structures, utilities, and

construction sites lies in our ability to accurately characterize soil behavior. Since soil is not a man-made material, its successful characterization

depends on its properties in the undisturbed state in the ground. Under this

project, tests will be conducted with the acoustic cone and correlated with

other in-situ and laboratory soil tests. From these data, the methodology for

in-situ measurement with the acoustic cone will be developed.

Design curves will be developed for the use of the cone penetrometer for

evaluation of the liquefaction potential of sites subjected to earthquake

effects. Also, Japanese Standard Penetration Test methodologies and equipment

will be studied to provide a better interpretation of existing Japanese subsurface exploration data from sites that experience liquefaction, which are presently used in our design curves for the Standard Penetration Test. This

research will lead to new, more reliable, and more efficient in-situ measurement methods. It will reduce the cost of foundations, reduce foundation failures, and increase the feasibility of construction on unstable sites by

providing a iQore reliable assessment of subsurface conditions.

11
IN-SITU MEASUREMENT OF SOIL PROPERTIES BY THERMAL METHODS

Lawrence A. Salomone

(301) 921-3128

Structures Division

Sponsor: National Bureau of Standards

The thermal conductivity of soil is significantly affected by soil

moisture. The correlation between moisture content and thermal conductivity

must be known for accurate predictions of energy dissipation of buried transmission lines and other structures surrounded by soils. Conversely, the correlation between moisture content and thermal conductivity may be used to measure

soil moisture content in-situ and to determine the plastic limit of clays in

the laboratory.

Under this project, measurement of thermal resistivity and its variation

with moisture content and density will be performed on two fine-grained soils,

one of a high plasticity, and one of a low plasticity. The concept generated

from last year's studies will be tested and expanded. Results will lead to

better modeling of heat dissipation in soils and to new methods of in-situ and

laboratory measurement of soil properties.

12
IN-SITU MEASUREMENT OF SOIL PROPERTIES BY ACOUSTICS

William D. Kovacs

(301) 921-2885

Structures Division

Sponsor: Bureau of Reclamation

Substantial laboratory research has recently been performed at the

University of California at Berkeley in the area of identification of soil

properties by acoustic methods. When these techniques are combined with a

cone penetration device, we gain the capability of identifying, in addition to

the shear strength parameters, other soil properties such as soil type, grainsize distribution, coefficients of permeability and relative density. A cone

which receives acoustic signals during penetration has already been tested

successfully in the laboratory. A more advanced type of cone is now available

for experimental research. This new cone will also be able to emit acoustic

signals and determine the response. The new cone, which will also be equipped

with piezometer, has the capability of substantially advancing the state-ofthe-art in in-situ measurements, but substantial field research is necessary

before the data can be interpreted and used in engineering practice. This project will carry out coordinated research in the field and laboratory, including

correlation studies with other in-situ devices, to develop reliable measurement

techniques.

13
CYCLIC STRAIN APPROACH TO THE DETERMINATION OF LIQUEFACTION POTENTIAL OF

LEVEL SANDY SITES

Riley M. Chung

(301) 921-2648

Structures Division

Sponsor: National Bureau of Standards

Relative density is currently used as the single important parameter in

preparing laboratory specimens of sand to model liquefaction potential under

in-situ conditions. Research now indicates that many other characteristics

of the soil are important such as the manner of deposition, history of preconsolidation, and history of vibration. These are collectively referred to as

the soil fabric. At present, two methods are used to predict liquefaction

potential of sites. In the first method. Standard Penetration Test results

from the site in question are compared with those from sites that liquefied in

the past. In the second method, reconstituted samples are subjected to cyclic

stress in the laboratory, using again Standard Penetration Test results to

determine relative density in the field. This project will determine the

correlation between cyclic strain and pore water pressure buildup and volume

change for a wide range of granular soils, and develop a new design approach

based on these correlations. This research will lead to a new, more reliable

method of determining liquefaction potential, cyclic mobility, and seismic

settlement of level sandy sites. It will also serve as the basis for further

research in geotechnical earthquake engineering.

14
GAGE FOR MEASUREMENT OF DYNAMIC SOIL STRESSES

Felix Y. Yokel

(301) 921-2648

Structures Division

Sponsor: Air Force

The in-situ measurement of stress in a soil mass poses difficult problems

because stress gages stiffer than the surrounding soil introduce disturbances

that distort the stress field. Also, the traditional method of determining

stresses via the measurement of strains does not work well in soils since

stress-strain relationships are complex and poorly understood. The problems

are magnified in the measurement of dynamic effects, which is further hampered

by the poor frequency response characteristics of available gages.

There is an opportunity for advancing the state-of-the-art in this

measurement area by the use of piezo-electric polymer material developed by

NBS. This material possesses two properties that make its use as a soilstress gage attractive. The polymer gages can be thin and flexible,

minimizing the disturbance in the stress distribution in the soil mass. And

also the gages have favorable dynamic response characteristics and could pick

up high-frequency puressure pulses.

The development of the gage also poses difficult technical problems, such

as uncoupling of stress and adiabatic heat effects, and uncoupling of compressive and shear stresses. If the gage is successful it will be widely used by

industry, government agencies, the armed forces, and research laboratories.

The gage will also improve the state-of-the-art in soil dynamics by providing

an accurate signature of pressure pulses which in the past where not available.

15
EARTHQUAKE

ENGINEERING

Technical Assessment of Earthquake-Resistant Design Provisions

Torsional Effects in Buildings Subjected to Earthquake Excitations

Fatigue Tests in Full-Scale Block Walls

Large-scale Bridge Columns Subjected to Reversed Cyclic Loading

Cyclic Loading of Masonry Building Components

16
TECHNICAL ASSESSMENT OF EARTHQUAKE-RESISTANT DESIGN PROVISIONS

E.V. Leyendecker

(301) 921-3471

Structures Division

Sponsor : Federal Emergency Management Agency

This project is a continuation of work with the Federal Emergency

Management Agency in its effort to support improvements in seismic design

criteria. CBT is participating with the Building Seismic Safety Council

(BSSC) in conducting its efforts in the private sector and with the Interagency Committee on Seismic Safety in Construction (ICSSC) in its activities

with the Federal agencies.

The BSSC is currently evaluating proposed seismic provisions through the

conduct of trial designs of buildings using the proposed revisions. CBT is

conducting technical studies for the BSSC Trial Design Overview Committee.

This work is done in coordination with other members of the Committee who are

voluntarily donating their time. Studies include preparation of a plan for the

conduct of the trial design program to evaluate the provisions and preparation

of the source document used for trial designs. CBT is working closely with the

BSSC in all phases of the trial design program.

Working with the ICSSC, CBT develops recommendations for future

substantive improvements in Federal seismic provisions. An existing draft

standard prepared for trial use by the ICSSC is based on current practice. It

is the first step in improving Federal standards, with its primary purpose to

introduce a uniform practice among all Federal agencies. Substantive improvements in the Federal seismic provisions for buildings will take several years

to accomplish and should be coordinated with the eventual improvement in the

private sector that will come about as a result of the BSSC activities.

CBT provides the chairman of ICSSC and of the ICSSC steering group and

provides the technical secretariat for ICSSC and its steering group. Additionally, staff members serve on various ICSSC technical committees and

provide the chair for the Committee on Building Standards.

17
TORSIONAL EFFECTS IN BUILDINGS SUBJECTED TO EARTHQUAKE EXCITATIONS

Spencer T. Wu

(301) 921-2198

Structures Division

Sponsor: National Bureau of Standards

The need for providing torsional resistance in buildings subjected to

earthquakes is well known. Development of rational criteria for seismic

design requires study of the behavior of structural systems subjected to seismic waves. However, the provisions in the current building codes are largely

based on engineering judgment. A design eccentricity of five percent of the

maximum building dimension is used in the Uniform Building Code and the Recommended Lateral Force Requirements of the Structural Engineers Association of

California.

The current investigation emphasizes theoretical analysis. The problem

will be formulated by considering all the significant effects, especially

soil-structure interactions. Dynamic eccentricity will be determined in the

timedomain to represent the level of structural response. Case studies will

be made to find the contributions of various parameters pertinent to the

characteristics of structural systems. Accidential eccentricities due to

horizontal propagating shear waves will also be investigated. The analytical

results of this research will improve the basic understanding of the torsional

effects in structures and thereby contribute to more consistent seismic design

provisions in building codes.

18
FATIGUE TESTS IN FULL-SCALE BLOCK WALLS

Kyle Woodward

(301) 921-2160

Structures Division

Sponsor: Bureau of Mines

The Bureau of Mines is responsible for providing inforaiation on the

levels of blasting that could cause damage to surrounding construction during

mining operations. Past history has revealed the need for defining first

cracking capacity of block walls. This and other types of construction have

been involved in a number of legal actions. The investigation will involve

experimental testing. Full-scale tests have been conducted by the Bureau of

Mines. They are seeking additional experimental data that only CBT has the

facility to provide. The experimental program will include tests on planar

wall specimens and corner specimens. Loading will include both load-rate

effect and cyclic-loading effect. Although the Bureau of Mines requirement

for information is limited to first cracking, the investigators plan to examine ultimate load capacity as well to fit this research into the overall CBT

research program on masonry construction.

19
LARGE-SCALE BRIDGE COLUMNS SUBJECTED TO REVERSED CYCLIC LOADING

William Stone

(301) 921-2193

Structures Division

Sponsor: National Science Foundation

A national workshop on earthquake resistance of highway bridges held in

January 1979 identified research needs and established priorities in the area

of seismic aspects of highway bridge design. One of the highest priority

research needs was to determine the effects of scale factor on bridge oolumn

design to determine whether the behavior of small sections can be extrapolated

to large cross sections and to examine the performance of selected full-scale

details. These two needs can be interrelated.

Experimental programs on large-scale specimens are expensive and

difficult to conduct; hence, the limited availability of data in the literature. The test program will examine full-scale performance data over a range

of axial loads and column designs. Such a range is necessary to examine the

effect of scale factor since such an effect will likely be dependent on the

column mode of failure. The program plan will consider columns designed using

state-of-the-art techniques. Specimens at full-scale, 1/3-3cale, and 1/6-

scale will be selected. Many of the tests will be full size to take advantage

of the NBS facility to obtain "bench mark" data. The scale tests that are

conducted are expected to identify problems of scale effect but may not completely answer them. If necessary, a complete examination of scale effect

will be possible in future investigations using the full-scale tests to

provide reference data.

20
CYCLIC LOADING OF MASONRY BUILDING COMPONENTS

Kyle Woodward

(301) 921-2160

Structures Division

Sponsor: National Bureau of Standards

The process of developing tentative seismic design provisions for both

unreinforced and reinforced masonry building components reveals a scarcity of

information on ultimate strength characteristics. Since seismic resistance is

now based primarily on ultimate strength considerations, the lack of such

information for masonry is detrimental to rational design of buildings subjected to seismic loadings. Here, experimental tests will provide vitally

needed information not now available that will serve as the basis for development of mathematical models. A number of failure modes will be examined to

identify the characteristics of each and the significant parameters affecting

the different failure modes.

Analytical expressions for predicting failure as a function of key

parameters will be developed. Later experimental testing will determine

the generality of the proposed analytical expressions. This research will

provide engineers with a sound base not currently available by presenting

experimentally verified rational approaches for ultimate strength design.

21
CONSTRUCTION

ENGINEERING

Construction Load Effects

Structural Condition Assessment Standards

Sonic-Pulse-Echo Inspection of Concrete

Performance of Concrete Structures in the Arctic

Safety in Concrete Construction

Development of Safety-Net Standards for Construction

22
CONSTRUCTION LOAD EFFECTS

S.G. Fattal

(301) 921-2184

Structures Division

Sponsor: National Bureau of Standards

Compared with the provisions for occupant protection, current codes and

standards provide little or no coverage on the protection of buildings during

construction. This is attributed to a lack of substantive information on construction loads and their effects on the partially completed structure and the

temporary support system. At the present time, the Equivalent Frame Method

prescribed by the ACI 318 Code allows the two-dimensional representation of

space structures for analysis. However, when floors are interconnected by

shores as in construction, analysis of the structure using an Equivalent Frame

Method gives inaccurate results. To achieve a reliable level of safety in the

design of concrete structures during construction, there is a need for the

appropriate load factors to be used. Under this project, a valid analytical

model for concrete buildings under construction will be formulated. The field

data on construction loads obtained earlier will serve as a guide in the

formulation of probabilistic models for construction-load effects.

This analytical basis for evaluating construction loads will lead to a

reliable procedure for design of concrete structures under construction. A

feasibility study of time-lapse photography in the evaluation of construction

loads will lay out the groundwork for large scale and relatively economical

construction load surveys.

23
STRUCTURAL CONDITION ASSESSMENT STANDARDS

James H. Pielert

(301) 921-3146

Structures Division

Sponsor: National Bureau of Standards

Throughout the U.S., increasing concern is being expressed for the need

to more fully use the existing building stock. Expenditures for improvements

to housing nearly matched those for new housing construction in I98I —$46.5

billion vs. $50 billion. The building rehabilitation process requires many

technical decisions by designers, builders, and building officials relative to

the condition of the existing building. But the data required to make these

decisions are broadly dispersed and not readily accessible. It is necessary

to subject such information to a consensus review and provide the design community with resource standards on building condition assessment for selected

materials — concrete, metals, masonry, wood, etc. In the end, this project

will provide a more uniform approach to building rehabilitation and a more

efficient use of the existing building stock.

24
SONIC-PULSE-ECHO INSPECTION OF CONCRETE

Nicholas J. Carino

(301) 921-3128

Structures Division

Sponsor: National Bureau of Standards

The detection of voids, cracks, and delaminations in concrete is

Important in determining its condition in both new and old structures.

Radiographic and ultrasonic methods can be used for inspecting the interior

of a concrete member, but only if opposite surfaces are accessible. With the

radiographic method, the concrete member must also be thin. A promising alternative is the sonic-pulse-echo method, in which only one surface needs to be

available and thick concrete members can be inspected. Ultrasonic pulse echo

is a standard method for detecting flaws in metals. .Sonic-pulse-echo methods

are based on a principle that sound waves propagating through a solid are

reflected by discontinuities such as a crack or porosity, or by interfaces

between phases of different densities or elastic moduli. Therefore, by

analyzing the signal due to reflected waves it is hypothetically possible to

determine the location of the heterogeneity of concrete, formation of shrinkage cracks, and normal porosity. Since even high-quality concrete can contain

numerous discontinuities, results from tests made on concrete are difficult to

interpret because of a lack of a fundamental understanding of the Interactions

of sound waves with discontinuities.

This project will form the basis for interpreting the results from pulseecho inspection on structural building materials and components. This will

encourage the use of NDE methods in inspecting new structures and those in

service.

25
PERFORMANCE OF CONCRETE STRUCTURES IN THE ARCTIC

Nicholas J. Carino

(301) 921-2647

Structures Division

Sponsor: Department of the Interior

Rising costs of fossil fuels have made it economically feasible to pursue

new sources in arctic regions that were previously considered impractical due

to environmental conditions. Large-scale concrete structures have been proposed and built, such as offshore drilling platforms, floating storage units,

and land-based facilities. The arctic offshore environment poses serious

problems for concrete structures and their durability. To enhance the productivity of structures in cold regions, there must be an understanding of the

behavior of concrete in these environments. The primary thrust of this

effort will be to document the state-of-the-art of construction methods and

durability of concrete structures in cold regions. A comprehensive literature

review will be performed including a survey of major groups involved in cold

region construction. In addition, a workshop will be sponsored by CBT and the

Canada Centre for Mineral and Energy Technology, which will bring together

experts in the design and construction of concrete offshore structures to

share past experiences and identify research needs. The proceedings of the

workshop will be published.

26
SAFETY IN CONCRETE CONSTRUCTION

S.G. Fattal

(301) 921-2184

Structures Division

Sponsor: Occupational Safety and Health Administration

In recent years there have been catastropic failures of concrete

structures during construction, some causing human casualties and all causing

construction delays. These incidents have been attributed to inadequacies in

design or construction, and have underscored the need for maintaining a consistent safety margin against collapse through a better understanding of the

nature and magnitude of imposed construction loads and their effect upon the

partially mature concrete structure and the shoring system used in its erection. The goal is to develop a technical basis for the improvement of existing safety standards on concrete construction. This year's work will consist

of the following tasks: reduction and analysis of construction load data

obtained from the field, verification (and refinement, if necessary) of the

analytical model against field data, and development of recommendations for

the improvement of the OSHA standards for safety in concrete construction.

27
DEVELOPMENT OF SAFETY-NET STANDARDS FOR CONSTRUCTION

Charles Yancey

(301) 921-2647

Structures Division

Sponsor: Occupational Safety and Health Administration

Falls from elevated surfaces during construction are the principal source

of worker casualties. Safety nets are used to impede falls in progress in

many situations where active fall-protection devices, such as guardrails and

safety belts, are either impractical, as in congested work areas, or are

ineffective due to the absence of an adequate mechanism of support. Currently,

there is no technical basis for the application and performance testing of

safety nets used in construction. The purpose of this study is to develop

comprehensive criteria for the use and testing of safety nets based on research

results. This phase of the study will address the question of the adequacy of

the minimum horizontal projections of perimeter nets that are currently widely

used.

28
SERVICE-LIFE

PREDICTION

Application of Life-Test Analysis Concepts to Building Materials

Cement Hydration

Performance of Concretes

Short-Term Evaluation Procedures of Coatings for Steel

Corrosion of Steel in Prestressed Concrete

Organic Coatings

Characterization of Blister Growth and Corrosion Under Protective Organic

Coatings

Corrosion and Weathering Data

Corrosion of Alumininum Roofing

Evaluation of Single-Ply Roofing Systems

Performance of Bonded Seams in Single-Ply Roofing Membranes

Performance of Residential Siding

Tri-Services Technical and Scientific Support

Guide Specifications for High-Performance Latex Paints

Standards for High-Security Glazing Materials

Solar Collector Durability and Reliability Test Program

Standards for Solar Absorptive Coatings

Environmental Degradation of Polymeric Cover Materials for Solar Collectors

Evaluation of Optical Techniques for Measuring Absorber Materials Degradation

Degradation of Heat-Transfer Fluids in Solar Heating Systems

Documentation of Materials Research Data and Activities

Performance Criteria for Solar Systems in Commercial Buildings

Residential Solar Data Center

Solar Energy International Cooperation

Buffers for Glycol-Based Heat Transfer Fluids

29
APPLICATION OF LIFE-TEST ANALYSIS CONCEPTS TO BUILDING MATERIALS

Jonathan W. Martin

(301) 921-3206

Building Materials Division

Sponsor: National Bureau of Standards

Reliable prediction of service life is needed to aid the selection and

use of polymeric building materials. But major technical barriers to the

development of predictive models arise from the complexity of the degradation

processes, particularly the synergistic effects of ultraviolet radiation, temperature, moisture, and other factors. Currently, predictive models and accelerated tests do not account for this synergism. The thrust of this research

is to develop stochastic models incorporating synergistic degradation effects.

These models will be validated against laboratory and outdoor test data.

Prior research has led to the development of a stochastic model as a

function of two of the above degradation factors (ultraviolet irradiance and

temperature) using polymethylmethacrylate (PMMA) as a model material. This

year the model will be extended to include moisture. PMMA specimens will be

exposed to several relative humidity levels, keeping irradiance and temperatures constant. The level of moisture in each specimen will be measured using

a Fourier transform infrared measurement technique. Degradation of the materials will be measured using gel permeation chromatography. In the mathematical modeling phase of the research, extensions will be made to the current

stochastic model. Degradation will be modeled in terms of the chemical/

physical changes occurring within the material.

The project will help put durability-related evaluation methodologies on

a probabilistic basis, advance the technology of service-life prediction by

providing an improved predictive model and by demonstrating an approach that

can be used with a wide range of building materials, provide an improved

understanding of the mechanisms of degradation, and identify paths of future

research for other building materials and components.

30
CEMENT HYDRATION

Paul W. Brovm

(301) 921-3458

Building Materials Division

Sponsor : National Bureau of Standards

Portland and related cements are essential to the Nation's construction

projects. Over $3 billion each year is spent on these materials, which are

used in concrete construction costing about $20 billion. With the growing

availability of computers, sophisticated analytical instrumentation, and laboratory automation, there are opportunities for improving our understanding of

cement hydration so as to make possible more reliable predictions of concrete

performance. Application of this knowledge will lead to improved standards

for cements, greater uniformity of cements, improved cements, more effective

use of material resources (including suitable wastes) in cement and concrete,

and greater productivity in the cement and concrete industries.

The main product sought from this project is an established competence in

cement science to provide a basis for significantly improved predictions of

the performance of cements in concrete. This includes microstructural investigations, measurement of hydration rates, and aqueous phase analyses all

leading to the development of mathematical models. Reports on the experimental

results and the mathematical models obtained during the competence building

are being published. The results of the research and its implications are

being brought to the attention of the cement and concrete community through

publications in the scientific and technical literature, through reports to

technical committees in ASTM, ACI , TRB, and RILEM, and participation in

Engineering Foundation Conferences on cement.

31
PERFORMANCE OF CONCRETES

Larry Knab

(301) 921-3120

Building Materials Division

Sponsor: National Bureau of Standards

Improved understanding of the cracking mechanisms and the effects of

environment on these mechanisms is needed for development of models for reliably predicting the performance of concrete. On a macroscopic level, there

has been considerable research on the cracking of concrete and several

attempts have been made to apply the fracture mechanics approach. It is now

clear that the classical fracture mechanics approach, based on Griffith's

theory of brittle fracture, does not give an accurate representation of cracking in concrete. A major obstacle in applying fracture mechanics is an

inadequate representation of the cracking process.

The purpose of this project is to investigate the damage zone in concrete

and develop analytical models describing the damage zone and cracking processes.

For example, a damage zone that acts as an energy sink, appears to surround

microcracks. However, the conventional fracture mechanics approach does not

adequately handle this damage zone. Quantifying the effect of the damage

zone on the cracking process and the strength of concrete will aid in the

development of an improved understanding of concrete deterioration and a basis

for more reliable service life predictions of concrete.

32
SHORT-TERM EVALUATION PROCEDURES OF COATINGS FOR STEEL

Jonathan W. Martin

(301) 921-3208

Building Materials Division

Sponsor: Federal Highway Administration

Each year state transportation bureaus spend hundreds of millions of

dollars protecting, from corrosive environments, bridges and other steel

components associated with highways. To a large extent, the magnitude of this

expenditure is affected by coating durability, for coating durability dictates

maintenance policy. Essential to the optimization of maintenance schedules is

an estimate of coating performance or service life obtained from short-term

tests and extrapolated to expected environmental and operating conditions.

Obtaining service life data before applying a coating is a difficult task.

The difficulty arises from the large number of material and environmental

stress variables.

Because of the enormous magnitude of research needed to fully satisfy

these objectives for all coatings and all exposure environments, it is essential

to narrow the focus of the initial research to include degradation caused by

the combined effects of temperature and moisture for only a few coatings.

While degradation may result from multiple factors (temperature, moisture,

ultraviolet radiation, cyclic exposure, salt, pollutants, etc.), temperature

and moisture are of primary importance for most coatings. Development of tests

to reliably predict degradation from these two factors will help meet the most

immediate needs and will lay the foundation for subsequent research involving

other degradation factors.

33
CORROSION OF STEEL IN PRESTRESSED CONCRETE

James R. Clifton

(301) 921-3458

Building Materials Division

Sponsor: Department of State

On the basis of a proposal submitted to the U.S. /Spain Advisory

Commission for Technology and Scientific Research on September 23, 1977, a

cooperative investigation between the Laboratorio Central de Estructuras y

Materiales, Centre des Estudios y Experimentacion de Obras Publicas y

Urbanismo (Spain) and CBT began in September 1978. The subject of the

research was "Factors Affecting the Corrosion of Steel in Prestressed Concrete

Structures" and the work was planned to extend over the 5- year period, 1978-

1983. Prestressed concrete is a form of reinforced concrete that makes highly

efficient use of concrete and steel but puts particularly severe demands on

these materials. The use of prestressed concrete for building and other construction such as bridges and pipelines is important in both the United States

and Spain, and its use is expected to grow. Although the problems encountered

with the performance and durability of prestressed concrete in the two countries appear to be different, there is a common basis of need for technical

knowledge about the problems. The purposes of this project are to develop an

improved understanding of the factors affecting the corrosion of prestressing

steel in concrete, and to contribute to the formation of a technical basis

for making service life predictions.

The results of this project will have a broad impact on prestressed

concrete technology through their influence on concrete standards and codes.

This project will also make a significant contribution to the bases for making

service-life predictions for prestressed concrete structures.

34
ORGANIC COATINGS

Mary E. McKnight

(301) 921-2635

Building Materials Division

Sponsor: Tri-Servioes Committee

The annual cost associated with the use of organic coatings in the U.S.

exceeds $8 billion, more than half of which stems from the use of protective

coatings in buildings and structures. If effective criteria for the selection

and use of protective coatings were available, as much as 25 percent of these

expenditures could be saved. An essential element of selection and use criteria for protective coatings is service life. But currently available methods

for predicting service life based upon short-term tests do not adequately meet

the need for data to aid selection and use. The objective of this research

is to develop improved test and evaluation methods for predicting the service

life of protective coatings under in-service use conditions; these methods

can be used as part of improved criteria for the selection and use of

protective coatings.

In developing the technical bases for improved test methods, this project

contributes directly to the improvement of the coatings technology used by the

military and also contributes to improvement of the nation's coatings technology through publications, specifications, and participation in ASTM activities.

The research on mathematical models and mechanical properties will aid in the

development of improved service life prediction methods. Data on service life

will lead to improved guidelines for the selection and use of organic coatings,

which will help in the reduction of maintenance costs.

35
CHARACTERIZATION OF BLISTER GROWTH AND CORROSION UNDER PROTECTIVE ORGANIC

COATINGS

Mary E. McKnight

(301) 921-2635

Building Materials Division

Sponsor: National Bureau of Standards

An important failure mechanism of protective coatings for steel is the

formation and growth of blisters beneath the coatings. These blisters ultimately lead to cracking and delaraination of the coating. The purpose of this

research is to understand, characterize, and model blister growth so that

improved predictions of service life can be made.

The research for this year will initially focus on ways to improve the

precision and accuracy of data obtained by infrared thermography, one method

used to detect and characterize blisters beneath coatings. These include

image quantification, use of newer equipment with better spatial and temperature resolution, and investigation of alternative measurement conditions,

e.g., changing temperature. Quantification and data handling will be developed

so that it is compatible with existing thermographic equipment as well as most

equipment now on the market.

Once the image quantification work is completed, research will be

performed to study rates of blister formation, blister growth, and corrosion

for selected pigments and vehicles as a function of such variables as pigment

type, pigment concentration, pigment size distribution, and coatings thickness. For a selected coating, blister growth as a function of concentration

of soluble substrate contaminates will be determined.

Work will also continue using a second characterization and detection

method, optical microscopy, with emphasis on determining rates of cathodic

delamination as a function of coating type, environment, etc. Results of the

experimental work will be used for further development of the preliminary

mathematical model that has been developed for predicting the formation and

growth of blisters beneath protective coatings.

The research will help in understanding corrosion mechanisms through

studies to validate the preliminary model and will then serve to improve the

performance of protective coatings. Also, the infrared thermographic method

will provide data to serve as a technical basis for more accurate and precise

evaluation standards than the currently used visual standards.

36
CORROSION AND WEATHERING DATA

James R. Clifton

(301) 921-3458

Building Materials Division

Sponsor: National Parks Service

This project is part of the nation's response to the acid rain problem.

It consists of two tasks. In the first, significant long-term atmospheric

corrosion and weathering data for metals, masonry, and coatings taken at

active exposure sites will be identified. This includes the identification of

any weather and pollution data taken at the exposure sites or at nearby monitoring stations. The second task is aimed at developing relationships between

the deterioration rates and the environmental conditions at the exposure sites.

The NBS Statistical Engineering Division will collaborate in the data analysis.

If adequate long-term weather and pollution data are not available at some

sites, the feasibility of estimating them based on short-term weather data

will be explored. Then, the significance of the relationships found between

material deterioration rates and weather data will be determined. Finally,

recommendations will be made on gaps where new rate data need to be produced.

The results of this research will be used in making the FY 1985 assessment of

the effects of acid precipitation on building materials.

37
CORROSION OF ALUMINUM ROOFING

Robert G. Mathey

(301) 921-2629

Building Materials Division

Sponsor: Defense Logistics Agency

Over 730,000 ft2 of aluminum standing-seam roofing was applied over builtup roofing that failed prematurely at the Defense Construction Supply Center,

Columbus, Ohio. The built-up roofing was applied only 7 to 8 years ago. The

aluminum standing-seam roofing is considered experimental for this type of

reroofing application because of the relatively low slope of the roofs. This

research will involve the monitoring, testing, and evaluation of the performance of low-scope aluminum standing-seam roofing in an area exposed to severe

"acid rain." Laboratory and field studies will be conducted to determine if

corrosion is a problem. The evaluation of the performance will give information that will contribute to the formation of a basis for estimating the service life of the aluminum roofing. Available information regarding

environmental conditions (Weather Bureau Data) to which the aluminum roofing

is exposed will be obtained and recorded. Measurements will be made periodically of the pH of rain water collected at the site. In evaluating the performance of aluminum roofing, the environmental conditions will be considered.

The results of this project will aid future decisions about the selection and

use of aluminum for roofing, particularly in a corrosive environment.

38
EVALUATION OF SINGLE-PLY ROOFING SYSTEMS

R.G, Mathey

(301) 921-2629

Building Materials Division

Sponsor: Tri-Services Committee

A recent survey projected that single-ply materials will account for 25

percent of low-sloped roofing by 1985. Furthermore, there are more than 100

products available and marketed as single-ply membranes in this country.

Standards and criteria for single-ply roofing materials have not been established in the United States. The lack of standards, accelerated evaluative

test methods, and performance criteria makes the selection and acceptance of

single-ply systems difficult. The objective of this investigation is to prepare preliminary criteria for single-ply roofing systems based on an analysis

of available information. This investigation will assist roofing research by

providing information to be used as a basis for development of conceptual and

mathematical models for roofs having sheet roofing membranes in order to

determine minimum performance levels.

39
PERFORMANCE OF BONDED SEAMS IM SINGLE-PLY ROOFING MEMBRANES

Walter J . Rossiter

(301) 921-3109

Building Materials Division

Sponsor: National Bureau of Standards

Since the mid-1970's, the use of single-ply membranes for low-sloped

roofing systems has increased rapidly. These materials now account for more

than 10 percent of the roofing membranes applied in low-sloped roof construction. A recent survey has projected that sheet membrane materials will

account for 25 percent or more of low-sloped roofing in I985. Installation

costs in 1985 for this amount of sheet roofing will range from $1.8 to $3-6

billion, if the present installation costs of $3 to $6 per square foot are

assumed

.

Currently over 100 sheet roofing membrane products are being marketed and

the number of products is increasing. The major types of membrane materials

are synthetic rubbers, plastics, and modified bitumens. Many of these materials are reinforced with a glass or polyester fabric. Seam fabrication techniques vary depending upon the type of material. A major problem has been the

failure of seams. In I98O, the National Roofing Contractors Association indicated that the most common problem reported by its members was the

delamination of sheet seams.

Standardized test methods and performance criteria applicable to seams

fabricated from the different types of sheet materials are not available to

determine whether a seam will perform satisfactorily. In this project, test

methods and performance criteria will be developed for evaluation of seam

performance. This project will help to minimize premature failures of the

$2 billion or more of sheet roofing membranes estimated to be put in place

every year from about I985 on.

40
PERFORMANCE OF RESIDENTIAL SIDING

Robert G. Mathey

(301) 921-2629

Building Materials Division

Sponsor: Tri-Services Committee

The increasing use of residential siding materials, both in new

construction and maintenance, has led to the need for performance criteria to

aid in the selection of materials. Of particular interest are criteria

addressing durability performance. The Department of Defense previously supported CBT research to develop interim performance criteria for sidings. During its first year, laboratory tests were conducted on repainting the weathered

siding materials. Adhesion tests using the field adhesion tester developed at

CBT were carried out to determine the compatibility of the alkyd and latex

coatings with the weathered substrates. The initial adhesion tests were conducted two months after repainting the siding materials. The repainted siding

materials were then exposed to outdoor weathering. Adhesion tests using the

field adhesion tester will be conducted on the repainted panels after 9 and 18

months' exposure. After 18 months' exposure of the repainted panels, data

will be analyzed, existing criteria evaluated, and criteria will be prepared

for recoating siding materials.

41
TRI-SERVICES TECHNICAL AND SCIENTIFIC SUPPORT

Robert G. Mathey

(301) 921-2629

Building Materials Division

Sponsor: Tri-Services Committee

This project will provide technical and scientific support and

consultative services on building materials and systems as required by the

Tri-Services. The work will include carrying out laboratory tests and field

investigations for solving building problems. Recommendations will be made

on the selection of materials and systems and their application and performance. In the past, problem areas have covered plumbing, masonry, roofing,

corrosion, mechanical systems, insulation, materials, and underground piping.

42
GUIDE SPECIFICATIONS FOR HIGH-PERFORMANCE LATEX PAINTS

Mary E. McKnight

(301) 921-2635

Building Materials Division

Sponsor: Air Force Engineering and Services Center

Recent failures of both interior and exterior latex paints have been

reported by a number of Air Force Bases. These failures include poor washability and scrubbability for interior paints and poor adhesion and durability

for exterior paints. Evaluation of preliminary data on high-performance

paints in the marketplace showed that their performance and durability may be

better than that of paints currently being used on military bases. Additional

experimental data are needed to provide the technical bases for improved

specifications

.

Under this project, performance requirements and essential attributes

of high-performance latex paint systems will be identified. Studies will be

conducted to identify the mechanisms by which currently used products are

degrading and thereby falling short in the required levels of performance.

Laboratory tests will be developed to assess paint systems to ensure that

performance meets the designated levels. These tests will be used as the

bases for new and improved criteria and specifications by the Air Force —

thereby extending paint lifetimes and lowering maintenance costs.

43
STANDARDS FOR HIGH-SECURITY GLAZING MATERIALS

James R. Clifton

(301) 921-3458

Building Materials Division

Sponsor: Law Enforcement Standards Laboratory

During this three-year project, the status and problerns of glazing

materials used in high-security applications will be determined, realistic

threat levels will be established, and performance tests and criteria will be

developed. Based on the information obtained in FY 1982, combined mechanical

and thermal attack was determined as one of the likely threat scenarios. Thus,

performance tests simulating combined mechanical and thermal attack will be

developed. Also, methods will be developed to determine the impact characteristics (velocity, force, and loading rate) of manually operated impact

tools, and will be used to calibrate mechanical impact devices used in the

combined mechanical-thermal tests. Performance tests for other threat types

including failure of the glazing as a unit and/or the window assembly are

needed but they cannot be accomplished within the scope of this project. The

major product will be a draft performance standard for glazing materials used

in high security applications. Also it will be brought to the attention of

ASTM Committee F12, which is concerned with security glazing, for possible

incorporation into ASTM standards.

44
SOLAR COLLECTOR DURABILITY AND RELIABILITY TEST PROGRAM

David Waksman

(301) 921-3114

Building Materials Division

Sponsor: Department of Energy

The reliability and long-teroi performance of solar collectors has not

generally been demonstrated. Recent studies have indicated that significant

changes in collector performance (greater than 10 percent) can occur as a

result of exposure to "no flow" conditions for 3 to 9 weeks. Various component and materials tests have been proposed to evaluate the reliability/

durability of solar collectors. However, these testing procedures have to be

experimentally validated. This project is intended to provide a coordinated

testing program that will result in establishing validated testing procedures

to relate laboratory, accelerated field, simulated operational exposure, and

actual field demonstration data for solar collectors used in building heating

and cooling applications. So far, these procedures have been incorporated

into the solar performance criteria and MPS documents that CBT has prepared

for HUD and DoE. In addition, they are being submitted to ASTM and other

concerned organizations for consideration as consensus standards and will be

of value in the establishment of testing procedures for the certification of

solar collectors.

45
STANDARDS FOR SOLAR ABSORPTIVE COATINGS

L.W. Masters

(301) 921-3458

Building Materials Division

Sponsor: Department of Energy

To maintain its efficiency, a solar heating system must retain its

original performance properties over the expected lifetime of the system. Of

prime importance to the system is the function of absorptive coatings in the

absorption of solar energy. While numerous standard test methods have been

developed for coatings in building construction, the performance requirements

involved in solar heating/cooling systems are quite different. For example,

temperatures on the absorptive surface may reach 475°F or greater, but standard test methods for coatings seldom involve temperatures as high as 212°F,

Standard test methods that can be used to evaluate absorptive coatings under

conditions of use are urgently needed. The purpose of this project is to prepare draft standards for absorptive coatings and predictive models to aid in

interpreting data from the standards. The standards will be based upon the

results of laboratory studies to evaluate available materials according to

the performance required of them in service. The draft standards will be

submitted to ASTM for consideration as consensus standards.

46
ENVIRONMENTAL DEGRADATION OF POLXMERIC COVER MATERIALS FOR SOLAR COLLECTORS

David Waksman

(301) 921-3114

Building Materials Division

Sponsor: Department of Energy

Virtually all of the durability testing that has been performed to date

on polymeric materials has concentrated on their degradation when exposed to

temperature and ultraviolet radiation. Little emphasis has been placed on

degradation caused by moisture or by the combined effects of moisture,

temperature, and solar radiation.

Under this project, moisture-related degradation that has occurred in

cover materials exposed in previous CBT programs will be characterized. Carefully controlled exposure tests will be conducted for representative materials

to determine their degradation mechanisms and degradation rates and a basis

established for projecting the useful lives of these materials. Research will

be performed to apply a stochastic mathematical model for predicting the

synergistic degradation effects of moisture, ultraviolet radiation, and temperature. The model will also be validated for one or more additional materials

to demonstrate its broad applicability.

Knowledge gained in this research will be of considerable value to

industry in formulating polymeric materials for solar applications. The

development of evaluation procedures, in cooperation with organizations such

as ASTM, will also aid industry in the selection and use of polymeric materials. The development of validated mathematical models also will significantly advance the current state-of-the-art in predicting the rate of

degradation of materials, which will, in turn, aid in providing evaluation

tools for selecting and using such polymers.

47
EVALUATIOM OF OPTICAL TECHNIQUES FOR MEASURING ABSORBER MATERIALS DEGRADATION

David Waksraan

(301) 921-3114

Building Materials Division

Sponsor: Department of Energy

Presently, integrated solar absorptance (per ASTM E424) and etnittance

(per ASTM E434) are the primary techniques used to measure changes in the

optical performance of absorptive coatings by the solar industry. These methods have been incorporated into ASTM procedures concerned with the evaluation

of absorptive solar receiver materials.

Studies conducted at CBT have shown that integrated solar absorptance

measurements are a poor indicator of change in the optical properties of

absorber materials. Such change typically occurs in the infrared region of the

spectrum and is concealed by the integration process conducted as part of ASTM

E424 . ASTM E434 measurements are a more sensitive indicator of changes in the

performance of selective absorber coatings; however, this technique provides

no information about the spectral distribution of changes in optical

performance of these materials.

Preliminary measurements made by CBT indicate that infrared spectral

reflectance measurements offer considerable promise as a technique for the

early detection of absorber materials degradation. Such techniques would be

of considerable value to industry in the use of short-term exposure tests as a

means for evaluating absorber materials.

The purpose of this research is to investigate the use of optical

property measurements for the early detection of absorber materials degradation. The optical properties of typical absorptive solar receiver materials

will be characterized by using techniques such as diffuse and specular infrared reflection spectroscopy, infrared emittance, and integrated solar absorptance. The sensitivity of these techniques to changes induced by short-term

aging tests will be determined. The results of these studies will be published in an appropriate technical journal and presented to organizations

concerned with the development of measurement techniques for absorber

materials.

48
DEGRADATION OF HEAT-TRANSFER FLUIDS IN SOLAR HEATING StSTEMS

Paul W. Brovm

(301) 921-3458

Building Materials Division

Sponsor: Department of Energy

One of the potentially major problems that may affect the durability of

a significant number of solar collector systems relates to the lack of information on the rates of degradation of glycol-based antifreeze solutions. This

is because the degradation of glycols generates acidic reaction products that

cause accelerated collector system corrosion. Ethylene glycol and proplyene

glycol may degrade by two major mechanisms under the conditions in a collector

system. These are thermal decomposition and oxidative decomposition. Preliminary work at CBT has indicated that ethylene glycol is thermally more stable

than propylene glycol but oxidatively less stable under one set of experimental

conditions. It has also been observed that the presence of certain metals

catalyzes the oxidative decomposition of glycols. Therefore, the degradation

kinetics of these compounds will be investigated as functions of temperature,

availability of O2, availability of CO2, and the presence of metals. Methods

of analysis including mass spectroscopy and ion chromatography have been

developed. This information will provide the basis for estimating the useful

lives of glycol-based heat-transfer fluids used under normal operating

conditions.

49
DOCUMENTATION OF MATERIALS RESEARCH DATA AND ACTIVITIES

Larry W. Masters

(301) 921-3458

Building Materials Division

Sponsor: Department of Energy

Since 1975, ERDA and DoE have devoted considerable emphasis and resources

to research and development activities pertaining to materials used in active

solar heating and cooling systems. These activities need to be documented so

that summary data and information (objectives, scope, results and conclusions,

reports published) will be accessible to researchers, materials developers,

and users. The information should be of considerable value and assistance to

manufacturers and developers in their selection and use of newer materials for

solar application. CBT, in cooperation with the other research facilities

involved with materials research (i.e., SERI, NASA, LANL) will compile an

annotated bibliography of research studies (1975-1981) related to active solar

materials performance. The document will be organized by subject matter for

ease of use. It is anticipated that a related effort will be undertaken by

Los Alamos National Laboratory (LANL) for the compilation of data and information which has resulted from materials research at LANL and through materials

R&D contracts monitored by LANL for DoE. The NBS and LANL efforts will be

coordinated and will result in either a joint publication or compatible and

coordinated separate publications. This project will aid manufacturers and

developers in the selection and use of newer materials for solar applications.

50
PERFORMANCE CRITERIA FOR SOLAR SYSTEMS IN COMMERCIAL BUILDINGS

Thomas Faison

(301) 921-3465

Building Equipment Division

Sponsor : Department of Energy

An interdisciplinary team, organized from CBT staff members and with the

assistance of outside contractors, participated in the preparation of draft

standards and performance criteria and is participating in the evaluation of

demonstration system performance. Experience gained from the evaluation of

system performance will be fed back into the development of improved criteria.

During FY 1981-1982, CBT staff assessed review comments resulting from a

request for public comment in the Federal Register by HUD for the proposed

document NBSIR 80-2095, "Performance Criteria for Solar Heating and Cooling

Systems in Residential Buildings." Comments were also solicited directly from

industry, professionals, standards organizations, as well as other Federal

agencies. The response to these comments also will provide material for

updating a document for commercial buildings.

51
RESIDENTIAL SOLAR DATA CENTER

Robert D. Dikkers

(301) 921-3285

Building Equipment Division

Sponsor: Department of Housing and Urban Development

In this program, raw data on commercialization and accelerated use of

solar heating and cooling are collected, stored, processed, and transmitted to

users and contractors for additional study, evaluation, and dissemination.

In FY78, the transcription forms for getting raw data onto the computer were

designed and put into use. The system for processing this data was then

designed and documented. A prototype of the system was written and tested,

the design was modified as needed, and computer programs and procedures were

written to implement the system. Documentation was written and users of the

system were trained. Since then, the program has been operational and has

been drawn on by numerous researchers. The building community will continue

to have access to this data through FRC or indirectly through technical reports

published by CBT researchers and other HUD contractors. Indirect benefits

come through standards and performance criteria developed by CBT and through

technical reports from other project participants.

52
SOLAR ENERGY INTERNATIONAL COOPERATION

Kent A. Reed

(301) 921-3465

Building Equipment Division

Sponsor: Department of Energy

CBT has a major role in the U.S. development of test methods for

determining the performance of solar energy components and systems for the

heating and cooling of buildings. DoE has requested that this expertise be

used to contribute to the international cooperative research in collector test

methods organized by the International Energy Agency as part of its Solar

Heating and Cooling Research Program. Specific objectives of the lEA collector

test task include improving our ability to characterize the thermal performance

of solar collectors, developing techniques for predicting the service life of

solar collectors, and most recently, developing methods to demonstrate that

installed solar water heaters are performing properly. CBT is contributing

results from its own as well as other U.S. solar research efforts, and is

facilitating the flow of technical information from abroad into the U.S. solar

program. The near-term product will be a series of technical reports produced

by the task participants. In the long terra, international standards for solar

collector testing and thermal performance evaluation of solar energy systems

will be developed by ISO using U.S. and other national standards.

53
BUFFERS FOR GLYCOL-BASfiD HEAT TRANSFtSR FLUIDS

Paul W. Brown

(301) 921-3458

Building Materials Division

Sponsor: Department of Energy

This project is intended to study a method for preventing an Increase in

the acidity of glycol-based antifreeze during system operation, and thus controlling a factor that contributes to accelerated corrosion. The technical

approach is to determine the effectiveness of the addition of common ions to

heated glycol-based heat-transfer fluids for maintaining the initial pH of

the solutions. The pH values of 50-percent byvolume solutions of the glycol

heat-transfer fluids are in the range of 8-9. The major acidic degradation

products of ethylene glycol have been identified as oxalic, glycollic, and

formic acids. Propylene glycol yields oxalic, lactic, formic, and acetic

acids. These organic materials are weak acids and not totally dissociated

in aqueous solution.

Soluble salts corresponding to the organic acids identified as

degradation products from ethylene and proplyene glycol solutions will be

added to the respective glycol-based heat-transfer liquids. These buffered

solutions will be heated and their stability monitored to determine the

effectiveness of the common ions added to suppress a decrease in solution

pH. This will be carried out as functions of solution temperature, solution

composition, and the presence of metals.

This research will provide the bases for recooimendations , suitable for

incorporation into standards, to protect solar components against corrosion.

54
QUALITY

ASSURANCE

NDE of Building Materials

Security Barriers

Development of Tests for Predicting Adhesive Bond Durability

Laboratory Accreditation: Solar Collector Testing

AASHTO Materials Reference Laboratory (AMRL)

Cement and Concrete Reference Laboratory (CCRL)

55
NDE OF BUILDING MATERIALS

James R. Clifton

(301) 921-3458

Building Materials Division

Sponsor: National Bureau of Standards

This project is a study of the existing and proposed methods for

nondestructive evaluation of in-place building components and materials. The

techniques are useful not only in day-to-day construction but also in rehabilitation of older housing stocks and evaluation of buildings after natural disasters such as hurricanes or earthquakes. The results of this project are being

brought to the attention of material scientists and material engineers through

workshops, presentations at national meetings, and publications. Its purpose

is to develop a technical basis to assist in the selection of appropriate NDE

methods.

56
SECURITi BARRIERS

James R. Clifton

(301) 921-3458

Building Materials Division

Sponsor : Defense Nuclear Agency

Previous work at CBT has demonstrated that man-passage openings could be

produced in security barriers in surprisingly short times using readily available portable equipment . The times have been short enough to require a

reappraisal of the use of these barriers for specific physical security

applications. These applications include storage of nuclear and conventional

weapons, radioactive material, secret documents, and precious metals. Furthermore, it appears that the deterrent capabilities of many barriers currently

accepted for security applications may provide little resistance to penetration

by newly-developed attack equipment such as the rotohammer, ring saw, Jet-Ax,

and burning bar

.

Many of the existing security barriers were constructed over 20 years ago

and some of them have deteriorated to an extent that they need to be repaired.

In addition, retrofit measures are being considered to upgrade the penetration

resistance of existing structures. It is necessary to determine the condition

of the existing building materials to select the proper repair of retrofit

method. The use of nondestructive evaluation methods for evaluating the condition of existing materials in security barriers will be explored in this

project.

This work will assist the Defense Nuclear Agency, other government

agencies, and private organizations. Further, it will contribute to understanding the performance of concrete subjected to impacts, explosions, earthquakes, and fires. Information from this study will also be applicable to

projects on rehabilitation and safety of buildings, earthquake hazard

reduction, and nondestructive evaluation.

57
DEVELOPt'ENT OF TESTS FOR PREDICTING ADHESIVE BOND DURABILITY

Jonathan W. Martin

(301) 921-3208

Building Materials Division

Sponsor: U.S. Army

All branches of the military use lightweight, air transportable, rigid

structures that serve as combination shipping containers and shelters for many

types of tactical and life-support services. The use of these shelters has

increased rapidly in recent years and life-cycle costs have become a major

consideration. The shelters are fabricated from either paper honeycomb core

or foam-plastic sandwich panels. While honeycomb panels have several potential advantages, field experience has shown many problems. Debonding of panel

components, stemming from poor adhesive performance, is a frequently observed

problem. To address poor adhesive performance, there is a need to develop

improved accelerated tests and probabilistic models to aid in predicting

service life.

This research will provide the technical bases for standards for

adhesives used in honeycomb sandwich panels. These standards will contribute

to the technical basis for the expansion of the military shelter program that

is to take place in the 1980's under the newly formed Joint Committee on Tactical Shelters. The benefits will be improved performance of military shelters

and spinoff benefits for civilian shelters.

58
LABORATORY ACCREDITATION: SOLAR COLLECTOR TESTING

Robert D. Dikkers

(301) 921-3285

Building Equipment Division

Sponsor: Department of Energy

This project will document the need for a solar collector laboratory

accreditation program. This documentation will be based in discussions with

solar collector manufacturers, collector testing laboratories, various

agencies and research organizations working in solar energy, and state solar

energy offices. The results of this work will be vital to further solarcollector testing and certification programs.

59
AASHTO MATERIALS REFERENCE LABORATORY (AMRL)

James H. Pielert

(301) 921-3481

Building Materials Division

Sponsor: American Association of State Highway and Transportation Officials

Under this project, with the support of AASHTO research associates

working under CBT supervision, measurement services are provided to both

public and private laboratories working on transportation studies. At present,

attention is focused on the testing of soils and bituminous materials and the

measurement of frictional properties of highways. Procedures used in performing conventional quality assurance tests are observed for conformance to applicable national standards. Related test apparatus is checked with inspection

equipment calibrated by CBT personnel or by AMRL personnel using CBT calibrated

devices. Deficiencies noted during inspections are brought to the attention

of laboratory managers. In addition, proficiency test samples are distributed

at regular intervals to obtain information on laboratory performance. Plans

for FY 1983 envision the distribution of 125 pairs of asphalt reference samples

three times during the year, 200 pairs of soil reference samples and 140 pairs

of aggregate reference samples two times each during the year, and 90 pairs of

bituminous concrete samples once during the year. Inspections of laboratories

and proficiency testing provide information about problems with test methods;

the AMRL staff participates in standards writing activities to bring these

problems to the attention of outside groups. At the request of the AASHTO Subcommittee on Materials, an annual listing of comments on the AASHTO standards

is forwarded for consideration by selected technical sections of the subcommittee. Coverage of apparatus and procedures used in the testing of cement and

concrete is delegated to the Cement and Concrete Reference Laboratory.

60
CEMENT AND CONCReTE REFERENCE LABORATORY (CCRL)

James H. Pielert

(301) 921-3481

Building Materials Division

Sponsors: American Society of Testing and Materials, U.S. Army Corps of

Engineers

Over $4 billion of hydraulic cements are produced in the United States

each year. The value of the concrete construction in which these cements are

used is estimated to be on the order of $20 billion. Because of the large

amounts of money and critical construction materials involved, standardization of testing to enhance the reliability of quality assurance measurements

is most important. The CCRL contributes to this standardization through onsite inspections of apparatus and procedures used in the testing of cements

and concretes, the distribution of proficiency test samples, laboratory

investigations of testing problems, and participation in the activities of

standards development groups. This work is performed by ASTM Research

Associates working under CBT supervision.

Plans for FY 1983 envision the distribution of 250 pairs of portland

cement reference samples and 170 pairs of concrete reference samples twice in

the year; and 150 pairs of blended cement reference samples and 100 pairs of

masonry cement reference samples once in the year. Inspections of laboratories

and proficiency testing provide considerable information about problems with

test methods; the CCRL staff participates in standards writing activities to

bring these problems to the attention of industry and regulatory groups.

61
CRITERIA AND

STANDARDS

standards Interface for Computer-Aided Structural Design

Representation and Analysis of Construction Standards and Specifications

Format for Model Building Codes

Documentation and Assessment of PBS Building Systems Program

Office Automation Impact on Interior Environments

Economic Methods for Building Standards

Development of a Solar Regulatory System

62
STANDARDS INTERFACE FOR COMPUTER-AIDED STRUCTURAL DESIGN

Frederick I. Stahl

(301) 921-2140

Structures Division

Sponsor: National Bureau of Standards

Computer-aided design (CAD) is critical to the improvement of

construction productivity. Computers have been used in a signfleant way to

aid engineering analysis for many years, and are now being used to aid in the

production of project drawings. However, major technical problems still lie

at the juncture between generic structural standards and project-specific

design conditions. Indeed, most of the computational effort involved in automated structural design concerns the checking of design properties against

constraints imposed by standards, building codes, specifications, and other

criteria. Researchers refer to this checking function as constraint processing, and agree that the efficiency and quality of constraint processing in

automated structural design can be enhanced by separating generic standards

data from project descriptive data and by linking these through a constraint

processor, or standards interface. In contrast, commercially available structural design software treats standards data as an integral part of proportioning and checking algorithms. An important shortcoming of this approach is

that entire software packages may be rendered obsolete whenever standardswriting bodies alter the contents of standards databases. By separating these

databases, software maintenance costs are expected to decrease significantly.

In addition, standards-writing organizations will be encouraged to test the

ramifications of changes they consider, by "swapping" standards data modules,

and simulating the benefits and costs associated with each in relation to

some standard building design.

GET research on the standards interface for CAD suggests a model for

design automation based on these objectives. However, an effective constraint

processor and an appropriate structure for organizing project-descriptive

structural design data remain to be developed. This project will eventually

speed-up and optimize the design of buildings. It has the additional benefit

that future CAD systems will be less costly to develop and maintain, and will

enable designs to be compared for alternative versions of building standards.

63
REPRESENTATION AND ANALYSIS OF CONSTRaCTION STANDARDS AND SPECIFICATIONS

Frederick I. Stahl

(301) 921-2140

Structures Division

Sponsor: National Bureau of Standards

CBT has sponsored with the Office of Product Safety Policy the development

of Standards Analysis, Synthesis and Expression Software (SASE). The SASE is

built upon the work of CBT researchers and others, and is a systeraatic method

for the analysis of standards, codes, and specifications. Now available for

use, SASE can support the analysis and formulation of a wide range of building

regulatory documents.

The initial software product delivered to CBT contained the minimal user

and technical documentation sufficient for use by experts, and contained no

tutorial materials necessary to train standards analysts in applying the system. Under contract with Carnegie-Mellon University, Dr. S. J. Fenves has

produced for CBT during FY82 and early FY83 a set of educational and training

documents built around SASE. These materials provide the basis for a series

of training seminars, and for the use of SASE by standards committee members

and other professionals. Wide dissemination of the new user-oriented technical documents and training aids, and for the software package itself, is a

high priority. An important forerunner of the kind of seminar envisioned is

the international workshop by correspondence on the rational analysis, formulation, and expression of standards, begun by CBT during FY82 , and endorsed

by CIB and ISO. With the delivery during FY83 of course outlines and other

training materials, it will be possible to plan training seminars specifically

oriented toward the needs of standards-writing organizations.

Work this year will include modifications or adjustments to the software.

Links to an available database management system also remain to the developed,

thus permitting the installation of SASE on a computer at NBS.

In the end, the SASE will provide a rational and systematic approach to

achieving standards that are clear, complete, and consistent. It also will

provide a basis for CBT research on the application of design criteria in

computer-aided design

.

64
FORMAT FOR MODEL BUILDING CODES

Frederick I. Stahl

(301) 921-2140

Building Physics Division

Sponsor: Federal Trade Commission

The three U.S. model codes exist in three formats. These

differences tend to increase costs and risks for designers, builders, and manufacturers working in multiple code jurisdictions; increase regulatory barriers

to the introduction of new technology; increase costs and risks of losses for

building owners; make comparisons of technical requirements in the model codes

extremely difficult; and provide barriers to reconciliation of differences in

the model codes. In addition, imperfections in the format of each individual

code make it difficult to find provisions applicable to specific technical

situations. As a result, the user is often unsure if all provisions have been

found, and whether relationships among the provisions have been interpreted

correctly. Such imperfections tend to increase errors and costs in construction, and create costly barriers to the introduction of new and improved

technologies.

As part of this project, Codes Community Committee (CCC) , including

persons knowledgeable in model code development and use, will be organized,

with support from the Federal Trade Commission. The CCC's function is to

develop a consensus recommendation for a uniform model code format. CBT will

provide technical support for the project in: analyzing the qualities required

of the format; providing information for defining the scope to be reflected

in the model codes; providing alternative organizations from which the CCC

may select one or more fitting the needs of model code users; and providing an

index that will define the location of all attributes and entities covered by

the scope of each of the three model codes.

Improved format for model building codes offers possibilites for

improving the quality of building regulations, enhancing opportunities for

the introduction of new building technology, and reducing building cost.

65
DOCUMENTATION AND ASSESSMENT OF PBS BUILDING SYSTEMS PROGRAM

Francis T. Ventre

(301) 921-3448

Center for Building Technology Headquarters

Sponsor: General Services Administration

This project will: assess how well the PBS Building Systems Program

(PBS/BSP) objectives were met in six facilities built to the program's specifications, recommend for PBS implementation opportunities for improved building technology and building procurement practices, report on the advisability

of implementing a prequalification approach to building procurement, and identify significant building technology and procurement issues whose resolution

will require further research.

The PBS Office of Design and Construction reported, in a professional

journal, that it was exceedingly difficult to evaluate virtually all existing

and proposed Federal office buldings because, at the time they were designed,

no description of what they were intended to accomplish had been prepared.

In the absence of such a description, reported the Senate Committee on Environment and Public Works, it is impossible "to later compare results with

inventories and learn what went right and what went wrong." The six buildings completed under the PBS/BSP are exceptions to the foregoing because

documentation on the intended technical objectives was prepared in advance.

The object of this project is to "compare results with intentions and learn

what went right and what went wrong." This project will define the PBS

Building Systems Program in terms sufficiently precise to permit subsequent

CBT assessment by using physical field measurements. Measurements will be

made at "systems" buildings selected from among the six actually built under

the program.

66
OFFICE AUTOMATION IMPACT ON INTERIOR ENVIRONMENTS

Arthur I. Rubin

(301) 921-2246

Building Physics Division

Sponsor : General Services Administration

The state-of-the-art of office automation (and plans for future

developments) will be compiled by means of a literature search, interviews,

and a conference. The data will be analyzed to identify environmental characteristics of offices required for the most effective use of automation, e.g.,

acoustics, lighting, thermal, etc. The goal is to identify the characteristics of the physical environment that should be considered in the design of

automated offices — those which are most likely to influence the performance

of office workers.

Using this information, and a review of documents concerned with the

development of design guidelines for buildings and interior spaces, an interim

guideline for the environmental design of automated offices will be prepared.

A sample of automated office tasks will be studied under field conditions to

evaluate the relationship of a limited number of environmental factors with

the performance of automated office tasks. The particular tasks and

environmental factors to be studied will be determined jointly by GSA and CBT.

67
ECONOMIC METHODS FOR BUILDING STANDARDS

Harold E. Marshall

(301) 921-3701

Center for Applied Mathematics

Sponsor: National Bureau of Standards

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 to help

the building community achieve affordable buildings that meet performance

objectives stems in large part from the rising costs of building materials,

the high costs of construction due to safety/environmental regulations, the

alleged decline in construction productivity, and the uncertain costs of

energy.

In this project, economic methods will be developed for application to

building problems. A report will be prepared on how to calculate discounted

payback and simple payback for building investments. This report will be used

by the ASTM EO6.8I Subcommittee on Building Economics in developing the fourth

in a series of recommended standard practices for evaluating the economics of

buildings and building components. Services will be provided to the ASTM

EO6.8I Subcommittee to transform techniques already published by CBT/CAM into

three additional ASTM-recommended standard practices for measuring the cost

effectiveness of buildings and building components. One is on the internal

rate of return; a second is on life-cycle costing; and a third is on benefit/

cost and savings-to-investment ratios. An important element in the work is

integrating ASTM and CBT inputs so that the resulting standard is useful and

consensus can be reached by ASTM,

Technical support will also be provided to the CIB W.55 Working

Commission on Building Economics and the CIB W.67 Working Commission on Energy

Conservation in the Built Environment. For W.55, contributions will be made

in developing measurement methods in three areas: life-cycle costs, construction productivity, and impact of building regulations. Technical leadership

will be provided the U.S. Committee of CIB Counterpart Working Commission W.55

in bringing CBT and ASTM work on building economics to the attention of CIB

W.55 and CIB W.67.

68
DEVELOPMENT OF SOLAR REGULATORlf SYSTEM

Francis T. Ventre

(301) 921-3448

CBT Headquarters

Sponsor: Department of Energy

A viable building regulatory system must be developed to accelerate solar

energy heating and cooling applications in housing and buildings and also to

protect the consumer. This solar regulatory system must complement the existing regulatory system and provide a mechanism to accominodate the acceptance

of a variety of solar systems, components, and modes of operation. In addition, a number of states and other jurisdictions are developing their own

solar regulatory systems and a multitude of uncoordinated, nonuniform regulations may slow the development of an efficient solar industry. Successful

completion of this program will discourage proliferation of these separate,

nonuniform solar codes.

Model solar building regulatory provisions were developed under the

sponsorship of the Council of American Building Officials (CABO) using the

ANSI "accredited organization" approach and published by DoE in June 1980

as "Recommended Requirements to Code Officials on Solar Heating, Cooling and

Hot Water Systems — Model Document for Code Officials on Solar Heating and

Cooling of Buildings." CBT, together with DoE and HUD, will provide oversight assessments regarding the progress of the program toward meeting its

overall goals.

69
THERMAL

INSULATION

Thermal Analysis and Modeling

Calibrated Hot-Box Measurements

Guarded Hot Plate and Heat-Flow Meter
THERMAL ANALYSIS AND MODELING

Frank J . Powell

(301) 921-3501

Building Physics Division

Sponsor: National Bureau of Standards

Under this project, the techniques of finite-element and response-factor

modeling will be used and developed in the analysis of the Calibrated Hot Box

apparatus and composite walls. The modeling of "flanking" loss through the

test-specimen holding frame and within complex walls is of highest priority.

Error analyses on the 1 -meter Guarded Hot Plate, Heat-Flow Meter, and Calibrated Hot Box will be done. Both analytical and finite element techniques

will be used to model losses and edge effects. In addition, the parametrical

dependence on the specimen thermal properties and physical dimensions will be

determined by statistical analysis. The insulation manufacturers and testing

community should welcome this improvement of the accuracy of their calibration

standards, so that lower-cost insulation can result and fairness among

manufacturers and between manufacturers and consumers will be enchanced.

71
CALIBRATED HOT-BOX MEASUREMENTS

Frank J. Powell

(301) 921-3501

Building Physics Division

Sponsor: Department of Energy

In the development of performance standards and specifications, the

need for better technical data and improved test methods for building materials and envelope systems is critical. This activity is a key element in

the DoC/DoE National Program for Building Thermal Envelope Systems and Insulating Materials. This year, assembly of the box will be completed and tests

for acceptance of the equipment from the contractor will be finished. Specimen walls constructed of materials selected for the ASTM C-16.30 Round Robin

(4-inch thick expanded polysytrene insulation board) will be used for these

tests. This project will help improve the technical base and test methods

needed by industry to reduce energy requirements of the envelopes of new and

existing buildings by 40 to 50 percent.

72
GUARDED HOT PLATE AND HEAT-FLOW METER

Brian Rennex

(301) 921-3195

Building Physics Division

Sponsor: National Bureau of Standards

This project will use the newly developed CBT line-source guarded hotplate and heat flow meter apparatus to experimentally obtain quantitative

data on the heat and mass transfer behavior of thermal insulation and building materials including the effects of moisture on thermal performance. The

designers and manufacturers of products that constitute the building materials

market will use the information to produce at lower cost with improved performance. An understanding and quantification of the phenomena occurring within

materials such as convection and/or moisture will also allow designers to

negate undesirable effects by designing around them. Further, research of

this type acts as a catalyst for innovative change to produce new and more

efficient materials and applications.

73
THERMAL

PERFORMANCE

Field Measurements of Wall Thermal Mass

Multi-Room Thermal Modeling

Underground Heat Distribution Systems

Earth Contact Heat-Transfer Modeling

Heat Loss through Thermal Bridges

Energy Analysis For ASHRAE-90A Revision

Energy Analysis Procedures

Air Infiltration in Large Buildings

Diagnostic Procedures for Federal Building Envelopes

Thermographic Mapping of Down Spouts in Treasury Building

Transient Performance of Building Defects

Laboratory Tests for Thermographic Standards

Energy Performance of Residences

Thermal Test Methods—Solar Collectors

Thermal Test Methods—Passive Components

Solar Hot Water Test Program

Response of Radiometric Converters to Sky-Radiance Distributions

Response of Radiometric Converters to Extended, Close Sources

74
FIELD MEASaREMENTS OF WALL THERMAL MASS

Douglas M. Burch

(301) 921-3754

Building Physics Division

Sponsor: Department of EnergySix 20-ft wide and 20-ft long, one-room test buildings have been

constructed at the NBS Nike Site. All six test modules have the same floor

plan, orientation, and other common features, but with differing wall constructions. During FY83, a one-week special-purpose test to measure the thermal time constants for the test buildings will be carried out. For this test,

the heating plants for the buildings will be turned off, and the decay of

indoor temperature will be monitored. The time constant is the time required

for the indoor temperature to decay to within 63 percent of its final steadystate value. The time constant is equal to the ratio of the envelope heattransfer coeffioient to the active envelope heat-capacity coefficient. The

purpose of the test is to permit the heat-capacity coefficients for the

buildings to be determined and subsequently used to correlate the "thermal

mass effect."

During the remainder of FY83, winter night temperature setback tests and

additional summer night ventilation tests will be carried out using the four

insulated test buildings. For the winter night tests, the thermostat set

temperature will be set back ten degrees during an 8-hour night period. The

effect of wall mass on the energy savings for night temperature setback will

be evaluated. For the summer night ventilation tests, the test buildings will

be naturally ventilated during cool night periods, and the cooling energy consumed by the test buildings during this mode of operation will be compared

with that consumed for the constant temperature thermostating mode of operation and with that for the FY82 night ventilation mode when power ventilation

was used as opposed to natural ventilation.

The experimental field data reported will provide a preliminary

validation of calculation procedures for predicting the impact of wall thermal

mass on residential heating and cooling requirements. When supplemented with

validating tests of full-scale residences in selected climates, the results

will enable HUD, ASHRAE, building designers, and materials trade associations

to perform credible evaluations of the cost-effectiveness of various design

and material strategies.

75
MULTI-ROOM THERMAL MODELING

George Walton

(301) 921-3633

Building Physics Division

Sponsor: National Bureau of Standards

This project will develop a comprehensive modeling technique for

predicting simultaneous transfer of air, moisture, and heat in and through

multi-room buildings. Although numerous building thermal modeling techniques

and computer programs exist throughout the United States, none of them can

handle the following processes simultaneously: envelope heat transfer,

envelope air leakage, envelope solar heat gain, room-to-room heat transfer,

room-to-rooffl air and moisture transfer, intra-roora air movement, energy consumption by the heating/cooling equipment, indoor comfort, water-vapor condensation, and contaminent migration. Existing models are virtually single-room

models and dynamic coupling between the heated/nonheated spaces and/or the

cooled/noncooled spaces are ignored.

Under this project, then, a comprehensive computer program package

similar to the NBS BSS 69 report on the NBSLD will be prepared. Also expected

are several technical and scientific papers on room air convection and interroom heat and mass transfer. By advancing the state-of-the-art of building

energy analysis, this project will assist the energy conservation design of

buildings. Especially improved will be design procedures for passive solar,

indoor air pollution, and smoke control.

76
UNDERGROUND HEAT DISTRIBUTION SYSTEMS

Tamami Kusuda

(301) 921-3501

Building Physics Division

Sponsor: Department of Defense Tri-Services Committee

Many underground heat distribution systems in military installations are

failing because of the corrosion of the conduit system that covers the thermal

insulation around the carrier pipe. Since it is an extremely expensive proposition to replace the entire underground system, it is desirable to have an

accurate and easy-to-use instrument that will detect only the segments of the

system that have failed. A simple heat transfer theory exists to translate

the ground temperature profile over the underground heat source if the thermal

properties of the earth and depth of the earth cover are unknown. This project

will develop a practical technique to measure the thermal conductivity and

temperature of the soil. This measurement system will be connected to a microcomputer for data analysis. When tested and validated, this technique is

expected to assist in the development of innovative underground heat systems

and encourage wider usage of existing underground systems.

77
EARTH CONTACT HEAT-TRANSFER MODELING

Tamami Kusuda

(301) 921-3501

Building Physics Division

Sponsor: National Bureau of Standards

CBT is currently developing a Green's function approach to solving the

slab-on-grade heat transfer problem. This method was able to prove that the

slab-on-grade problem can be analyzed by a combination of two analytical solutions, one dealing with a steady potential flow solution between the heated

plane segment and the surrounding earth; the second is the two-dimension perimeter zone solution dealing with the periodic temperature fluctuation developed

by Delsante. The combination of these two solutions permit the frequency

domain analysis of the slab-on-grade floor heat-transfer problem. This solution can be combined with the conduction-transfer function for the onedimensional multilayer slab structure to complete the solution for the composite slab-on-grade floor system where the effective slab insulation can be

studied. It is further proposed that this frequency-domain solution technique

for the floor slab be extended to the basement wall/floor problem. The new

algorithms developed under this research will be submitted to the AHSRAE Technical Committee on Load Calculations TC 4.1 and Energy Calculations TC 4.7 for

their adaptation to proposed procedures for building heat transfer analysis.

78
HEAT LOSS THROUGH THERMAL BRIDGES

Richard A. Grot

(301) 921-3470

Building Physics Division

Sponsor: Department of Energy

Infrared thermographic inspection of the exterior and interior of a

building envelope can reveal the locations and extent of thermal bridges in

most classes of structure. However, thermography is not capable of quantifying the heat loss from such thermal bridges. This project will classify the

types of thermal bridges occurring in typical commercial structures. Twodimensional and three-dimensional heat flow models for each class of thermal

bridge will be used to determine the location at which temperature and heat

flow probes must be placed on the structure to measure the heat losses due to

the thermal bridges and also to determine the minimum duration of measurements

which will allow a reasonable estimate of the annual heat loss from the thermal

bridge. A thermal bridge in an existing building will be monitored using the

developed technique to assess the accuracy of the method. The results of

this study can be used to decide whether it is economically sensible to fix

a thermal bridge and to determine the long-term energy costs of thermal bridges

about to be incorporated in new buildings.

79
ENERGY ANALYSIS FOR ASHRAE 90A REVISION

J. P. Barnett

(301) 921-3633

Building Physics Division

Sponsor: Department of Energy /

In this project, CBT will conduct a comprehensive set of annual energy

consumption analyses for ten different commercial buildings under five different climatic conditions with respect to seven different designs: 1) ASHRAE

90-75 design, 2) ASHRAE 90A-80 design, 3) ASHRAE 90A-80 design with new

chapter on systems and equipment, 4) ASHRAE 90A-80 with upgraded lighting

criteria, 5) ASHRAE 90A-80 with upgraded envelope criteria, 6) ASHRAE 90A-80

with all upgraded criteria, and 7) same as (6) with daylighting application.

These energy analyses will be conducted using the hourly simulation computer

program D0E-2.1B.

80
ENERGY ANALYSIS PROCEDURES

Taraami Kusuda

(301) 921-3501

Building Physics Division

Sponsor: Department of Energy

The success of the Building Energy Performance Standard hinges on the

availability of accurate, yet easy-to-use energy analysis procedures. Although

DoE has identified the DoE-2 program as the standard benchmark energy analysis

procedure, this program is often cumbersome for use by practicing engineers and

energy officials because it is complex and requires large computers. To make

effective use of DoE's BEPS, it is necessary to have manual energy-analysis

procedures, which CBT was asked to develop and validate. A step-by-step

procedure suitable for microcomputers was developed for performing simplified

energy analysis for commercial and residential buildings.

CBT also developed simplified and comprehensive slab-on-grade and basement

heat-loss calculation procedures for use in the hourly energy calculations.

The algorithms will be tested on NBSLD before application to the DoE-2.1B

computer program.

81
AIR INFILTRATION IN LARGE BUILDINGS

Richard A. Grot

(301) 921-3470

Building Physics Division

Sponsor : Department of Energy

Compared with single-family dwellings, there is very little experimental

data on the air-exchange behavior of large buildings. This is one of the

crucial parameters in modeling energy usage, because heat transfer due to

uncontrolled air leakage effectively bypasses insulation provided in the

building envelope. In some buildings, more than one-third of the building

thermal load is due to air leakage. Under this project, instrumentation for

measuring the air exchange rate in the Collins Building in Glasgow, Scotland,

and for the Park Plaza Building in New Jersey has been installed. These

systems monitor the air exchange rate, the operation of HVAC and exhaust system fans, interior and exterior environmental parameters, and the surface

pressure distribution across the envelope of the building. The FY83 effort

will consist of gathering detailed air infiltration rates in eight additional

buildings. CBT automated air infiltration equipment will be installed for

one or two weeks in each of the major climatic seasons for these buildings.

Better knowledge of infiltration rates and air leakage characteristics of

large buildings will provide much needed information for modeling of buildings. Better modeling will lead to energy savings through improved construction to reduce unwanted infiltration, better accounting of irreducible

infiltration for use in lieu of part of the mechanical ventilation load, and

an economically effective design through balanced consideration of insulation

and infiltration.

82
DIAGNOSTIC PROCEDURES FOR FEDERAL BUILDING ENVELOPES

Richard A. Grot

(301) 921-3^470

Building Physics Division

Sponsor: General Services Administration

This project will recommend diagnostic inspection procedures,

measurement techniques, and intepretation methods for use in assessing the

thermal integrity of Federal buildings. The product of this effort will be

an interim technical report describing diagnostic procedures for Federal

buildings and eight case histories of defects found in field tests. Practical

and timely methods of pinpointing specific corrective actions will not only

reduce the cost of eliminating energy-wasteful deficiencies, but will provide

GSA with information feedback of great value in improving construction and

retrofit practices.

83
THERMOGRAPHIC MAPPING OF DOWN SPOUTS IN TREASURY BUILDING

Richard A. Grot

(301) 921-3470

Building Physics Division

Sponsor: General Services Administration

Many old historical buildings have roof drainage systems whose locations

are unknown. These drainage systems often leak and cause damage to the building. A non-destructive method is needed for locating these drainage systems

30 that repairs can be made.

CBT will use thermographic methods to produce a map of the down spouts and

roof draining system in the treasury building. The down spouts will be mapped

by blowing hot air into the roof drains on a section of the building. CBT

will perform a thermographic survey of the building from the exterior to determine where the down spouts are and translate this information to architectural

drawings. If parts of the drainage system are not observable by exterior

thermographic scanning, interior scanning will be performed. Two representative sections of the roof drainage system will be removed for NBS chemical

analysis to determine the deterioration of the materials.

84
TRANSIENT PERFORMANCE OF BUILDING DEFECTS

Jin B. Fang

(301) 921-2278

Building Physics Division

Sponsor: STRS

Theoretical models of transient performance of building defects will be

developed to aid in quantitative interpretation of thermographic data.

Included are surface models for each class of defect in the thermal envelope

(voids, cracks, corners, thermal by-passes, moisture under solar loading, etc.)

typically observed during the thermographic inspection of buildings. The

models will be used with image processing equipment to generate theoretical

thermograms of these defects under various transient conditions. Transfer

functions representing the physical performance characteristics of the various

types of thermographic equipment will be used with the theoretical thermograms

to assess the ability of the equipment to observe and quantify the heat loss

caused by a defect under transient conditions.

Thermography has proven useful for qualitative assessment of the building

envelope. The extraction of quantitative data from thermographic surveys

requires a more detailed analysis of the physical processes in buildings which

produce the thermal patterns observed during thermographic inspections. A

series of guidelines will be developed for quantitative assessment of data

obtained from thermographic inspections of buildings. In FY83 the theoretical basis for such guidelines will be established. The guidelines from this

project will be used by ASTM and ISO subcommittees in developing standards

for the thermographic inspection of building envelopes.

85
LABORATORY TESTS FOR THERMOGRAPHIC STANDARDS

Richard A. Grot

(301) 921-3470

Building Physics Division

Sponsor: Department of Energy

In this project, ground-based infrared imaging systems and inspection

techniques will be evaluated for their application to building heat loss

detection. The adequacy of various standards for thermographic inspections

such as the ASHRAE standard, the draft ASTM standard, and the ISO standard

will be assessed. CBT will perform the laboratory test procedures suggested

in these standards. The evaluation of the equipment specifications for

spatial resolution, thermal resolution, noise characteristics, geometrical

response, signal transfer function, and summary measures will be carried out

in the laboratory on candidate infrared sensors used for building inspections.

The laboratory evaluations will be performed in CBT environmental chambers to

assess the effect of both object temperature and ambient temperature on the

equipment parameters. The results of these laboratory tests will be correlated

with observed building defects to determine the importance of each equipment

parameter on the conditions under which the equipment is used for heat loss

detection. This project will lead to guidelines for assessing the benefits of

thermographic inspections of buildings and the relative advantages of various

classes of thermographic equipment.

86
ENERGY PERFORMANCE OF RESIDENCES

Richard A. Grot

(301) 921-3470

Building Physics Division

Sponsor: Department of Energy

This project will use the data obtained from more than 100 houses in the

CSA Optimal Weatherization Demonstration project to assess various combinations

of simplified test methods that could be used to predict the whole-house performance of the dwelling and to signal changes in the energy performance. The

techniques which will be assessed are: air infiltration rate measurements by

both the pressurization method and the tracer gas method, electric co-heating,

infrared inspections of the building envelope, methods for measuring the seasonal efficiency of the building heating and cooling systems, and methods for

data handling, analysis and prediction of the energy losses due to the defects

detected. The assessments resulting from this project will be presented at

various meetings of building and utility trade associations and professional

societies such as ASHRAE and A3TM.

87
THERMAL TEST METHODS— SOLAR COLLECTORS

Kent A. Reed

(301) 921-3465

Building Equipment Division

Sponsor : Department of Energy

It is critical to establish the conditions required to maintain

comparability in solar simulator testing, and to determine what measurements

must be made to understand the differences that do occur, before solar simulator testing becomes too well entrenched. There are already three commercial

solar simulator test facilities in the United States, a large Federal facility

in Canada, and there are or soon will be as many a thirty in Europe. Under

this project, the solar simulator facility built for DoE at Marshall Space

Flight Center is being recreated at NBS. Short engineering research studies

will be conducted with representative generic collectors including flat plate

and evacuated tubular types to characterize the effects of spectral quality,

collimation, nonbeam radiation, and effective sky temperature. Other solar

simulator facilities will be used as appropriate.

88
THERMAL TEST METHODS—PASSIVE COMPONENTS

Michael McCabe

(301) 921-2308

Building Equipment Division

Sponsor: Department of Energy

Surveys to identify commercially available passive solar products based on

advertising in solar product directories and review of papers presented at

technical conferences and symposia will be continued to identify new products

being marketed. Thermal performance test procedures and test data for these

products will be reviewed, when available, and compared for generic groupings

of these products to establish a common basis for thermal performance testing.

Potential users of these products will be surveyed to determine the thermal

performance test data and required reporting format.

Passive solar components have been classified into generic groupings

according to their fundamental roles and a proposed thermal test procedure

will be developed for each grouping. Analytical computer models will be

developed for each grouping and representative components will be purchased.

Thermal performance testing under both laboratory conditions at other facilities and under field conditions at the NBS Passive Solar Calorimeter Facility

will be performed. The test data combined with the thermal modeling will be

used to assess the ability of the proposed test procedures to provide

appropriate thermal performance data.

89
SOLAR HOT WATER TEST PROGRAM

A. Hunter Fanney

(301) 921-3620

Building Equipment Division

Sponsor : Department of Energy

Experimental investigations are being carried out to test the thermal

performance of innovative water-heating systems. Electric strip heaters

attached to the absorber plates will be used to simulate the solar input. At

least one system will also be tested in a solar simulator. These experiments

will establish the testing procedure required for these systems and provide

detailed system performance data required to validate performance models. To

complete this research, the test methods and evaluation procedures must be

extended to include systems where circulation is driven by solar input such as

thermosyphon and refrigerant-charged water heaters.

90
RESPONSE OF RADIOMETRIC CONVERTERS TO SKY-RADIANCE DISTRIBUTIONS

Kent A. Reed

(301) 921-3465

Building Equipment Division

Sponsor: National Bureau of Standards

Existing test and evaluation procedures for building thermal equipment

using solar radiation assume either that there is no diffuse sky radiation

or that the diffuse sky radiation present is isotropic. Neither assumption

is correct. A sizeable portion of the prevailing uncertainty in equipment

testing can be attributed to the fact that the diffuse sky radiance is nonisotropic. The problem is particularly severe in testing innovative equipment

that responds to nonisotropic radiation in ways different from the instruments

used to measure the radiation. Since the equipment and the instruments are

just different kinds of radiometric converters, some with electrical outputs,

some with thermal outputs, the generic problem is one of characterizing the

response of radiometric converters to sky radiance distributions.

Completion of this work will remove a major roadblock in the development

of realistic rating procedures. It will provide the model for simulating

long-term performance for the purpose of evaluation and rating. Working from

the rating requirements, it will establish required modifications to current

standard test methods.

91
RESPONSE OF RADIOMETRIC CONVERTERS TO EXTENDED, CLOSE SOURCES

Kent A. Reed

(301) 921-3465

Building Equipment Division

Sponsor: National Bureau of Standards

Testing and evaluating building thermal equipment in environmental

simulation chambers is oommon practice. These chambers establish controlled

conditions of temperature, humidity, and air flow appropriate for a test.

Better test results can be obtained in less time in these controlled, stable,

conditions. Recently, some laboratories have added another dimension to the

controlled environment by installing large-area lamp arrays that simulate

solar radiation. It is relatively easy to reproduce typical outdoor levels

of irradiance using these arrays. However, the equipment under test and even

the instruments used to measure the optical and thermal radiation often behave

differently in these environmental/solar simulation chambers than they do outdoors because the lamp arrays are extended, close sources. Test methods and

evaluation procedures must be developed that properly account for these differences. The instruments and equipment are just different kinds of radiometric converters, some with electrical outputs, some with thermal. Thus, the

problem is one of characterizing the optical and thermal interaction of

radiometric converters with extended, close sources.

This work will establish the technical basis for developing test methods

and evaluation procedures for appropriate testing in environmental/solar simulation chambers. The immediate impact will be on the standards organizations

developing such procedures for building thermal equipment.

92
BUILDING ACOUSTICS

AND LIGHTING TECHNOLOGY

Acoustic Measurements for Buildings

Prevention of Traffic-Noise Problems

Visual Criteria

Task-Lighting Criteria

Illumination System Measurements

Optimized Model for Brightness

New Definition of Photometry

High-Efficiency Lights and Chromatic Response

Opponent-Color Approach to Color Appearance

Daylighting Studies

CEL-1 Lighting Program

The Use of Hazard Pictorials/Symbols in Mines

Hazard Pictorial Signage for Sand and Gravel and Crushed Stone Mines

93
ACOUSTIC MEASUHEMENTS FOR BUILDINGS

Simone L. Yaniv

(301) 921-3783

Building Physics Division

Sponsor: National Bureau of Standards

The acoustical properties of building materials, spaces, and systems and

the acoustic power emitted by sources are currently inferred from far-field

measurements of sound pressure levels using diffuse sound field theory — a

theory inappropriate for most situations. As a result, laboratory and field

data are inaccurate and predictions of in-situ performance from laboratory

data unreliable. A recent ASTM round robin showed that absorption coefficients of specimens tested in 16 laboratories vary by as much as 14 to 90

percent depending on frequency. Sound insulation data on nominally identical

structures varied by a factor of 3 to 10. Transmitted sound energy measured

in the field was 10 to 100 times greater than predicted. Unreliable data

bases and test methods and reliance on diffuse sound field theory can result

in costly overdesign or corrections after the fact. An error by a factor of

2 in sound insulation can result in a panel specification that is 90 percent

more massive than required and costs 60 percent more.

Poor measurement and prediction technology in building acoustics is

becoming a significant problem to the building industry since the number of

cities having enacted laws containing quantitative acoustic requirements

jumped from 50 in 1971 to 500 in I98O and the number of building codes incorporating acoustic specifications jumped during the same period from 10 to 100.

As more architects and developers are held responsible for meeting acoustic

specifications, the need for accurate test methods, data bases and reliable

predictions are sharply increasing. The results of this study may reduce

measurement uncertainties by a factor of 2. Further, work on the properties

of sound absorptive materials may reduce reliance on expensive acoustical

absorbers while at the same time opening the market to new inexpensive or

innovative materials.

9h
PREVENTION OF TRAFFIC NOISE PROBLEMS

Siraone Y . Yaniv

(301) 921-3783

Building Physics Division

Sponsor: Federal Highway Administration

The purpose of this project is to provide local government staffs with a

simple method and a handbook, based upon available technology, including

individual steps required to plan land use and building construction compatible with expected noise. The proposed handbook would integrate transportation noise prediction, site noise exposure, building envelope noise isolation,

and building occupants' noise exposure. The document will provide a stepby-step description of the design process indicating how local data are incorporated into the evaluation of the building envelope noise isolation and the

technical feasibility of achieving an acceptable environment through land use

planning and control. Numerous examples will be presented to illustrate the

use of the methodology. The text will be written in a "how-to-do-it" format

using examples and graphics to illustrate the concepts embodied in the method

developed. Technical details will be presented in a series of appendices.

95
VISUAL CRITERIA

Gary T. Yonemura

(301) 921-2680

Building Physics Division

Sponsor: National Bureau of Standards

This project will develop a methodological basis and supporting data for

standardizing lighting criteria for buildings. Laboratory research at CBT

indicates that when visual sensitivity is measured by conspicuity of details

(suprathreshold) , the function relating luminance with contrast is different

from that obtained when the visual task is threshold detection. An apparatus

to assess conspicuities of office tasks relative to a reference five-bar

target at suprathreshold levels has been constructed, tested, and calibrated.

By direct comparison methods, the relative difficulty of two-dimensional

office tasks will be assessed by varying the contrast of the five-bar reference task for equality in conspicuity. This project will contribute standardizing procedures, an apparatus, and a data base for evaluating visibility that

is applicable to real-world interior lighting.

96
TASK LIGHTING CRITERIA

Gary T. Yonemura

(301) 921-2177

Buildings Physics Division

Sponsor: Lawrence Berkeley Laboratories

Laboratory research at GET indicates that when visual sensitivity is

measured by conspicuity of details, the function is different from that

obtained when the visual task is threshold detection or suprathreshold contrast sensitivity. A visibility meter (conspicuity apparatus) was designed

and built at CBT. Using this apparatus, the legibility of typical office

tasks, as encountered in the real world (suprathreshold), will be assessed to

a reference five-bar reference task. The simultaneous effect of the many task

variables (e.g., contrast, color, size, blur, gloss, form and conspicuity)

will be assessed to obtain the relative visual difficulty of various office

tasks. These research findings are being presented to the Illuminating Engineering Research Institute (lERI) Energy Management Committee and the Recommendation of Quality and Quantity of Light Committee of the Illuminating

Engineering Society of North America (lESNA) and in articles in the United

States and European lighting journals.

97
ILLUMINATION SYSTEM MEASUREMENTS

A.T. Hattenburg

(301) 921-2680

Building Physics Division

Sponsor: National Bureau of Standards

Building illumination practice has historically relied upon simplistic

measurements of illumination levels, poorly defined reflectance values, and

complex calculation schemes based upon inadequate data. New requirements for

more cost-effective, energy conserving illumination systems are creating a

demand for more precise, valid physical measurement techniques to guide systems design, evaluate the effectiveness of prototype and installed lighting

systems, and contribute to the physical basis of vision research.

This year the performance of several potential near-field photometry

methods will be evaluated in the laboratory for accuracy in measuring luminance distribution for office-sized workspaces. Methods for reflecting determinations of room enclosure materials will be investigated to contribute to

second-generation design computations. The most promising method will be

developed and more fully evaluated next year. The development and acceptance

of these physical measurement methods will significantly contribute to the

provision of more economical and productive lighting systems in buildings.

98
OPTIMIZED MODEL FOR BRIGHTNESS

Gerald L. Howett

(301) 921-2670

Building Physics Division

Sponsor: National Bureau of Standards

This project will contribute to a redefinition of photometry by

developing a new formula that more accurately predicts the perception of

brightness. Experiments have shown, for example, that when a very saturated

red light is matched in brightness to a white light, the luminance of the

white light is twice—or, in another experiment, four times—that of the red

light, for the average observer.

The output of this research, the new formula for brightness, will be

offered to the vision/lighting community for adoption. Its impact could be

great: following a redefinition of photometry, DoE will presumably rewrite

the regulations governing maximum permissible lighting levels in various

types of buildings in terms of the new measure of amount of light. The CIE

and lES will presumably also redefine the energy efficiency (luminous efficacy)

of lamps in terms of the new definition of light output.

99
NEW DEFINITION OF PHOTOMETRY

Gerald L. Howett

(301) 921-2670

Building Physics Division

Sponsor: Department of Energy

This project will contribute to a redefinition of photometry by

developing new formulas that agree more accurately with perceptions of brightness. Several multi-channel brightness models have already been published by

vision scientists. In addition, a number of experiments yielding brightnessmatching data for various viewing conditions are in the literature, although

no such data set is considered definitive. A full-scale effort in this area

will require the collection of extensive visual data, radiometric measurements,

and computer modeling. CBT is already working in this area, with a project

called "Optimized Model for Brightness." That project involves optimizing a

generalized linear model of brightness so as to agree as well as possible

with the most extensive single body of brightness-matching data currently

available (a study done at the National Research Council of Canada). This

project is a desirable extension of that effort. In this work, an existing

nonlinear model will be generalized and optimized to best fit the same body of

data. Since the nonlinear model is more elaborate than the linear one, the

expectation is that a significantly better fit will result.

The development of a generally accepted redefinition of photometry would

provide the basis for possible redefinition of the candela, an SI unit, the

revision of lES Handbook and standards used by illumination system designers;

the redefinition by CIE and lES of the light output and the energy efficiency

(luminous efficacy) of lamps; and upgrading of performance standards for

energy efficient building illumination systems (e.g., ASHRAE/IES Standard 90A)

for reference by building designers, state and local building code officials,

and agencies concerned with construction and operation of Federal buildings.

100
HIGH-EFFICIENCY LIGHTS AND CHROMATIC RESPONSE

Belinda L. Collins

(301) 921-2670

Building Physics Division

Sponsor: National Bureau of Standards

Many high-efficiency light sources are known to alter color appearance.

The magnitude and duration of the distortion have not been determined. Pilot

research at CBT has suggested that color sensitivity may be altered (chromatic

adaptation occurs) significantly for up to 0.4 hours. Such shifts alter the

appearance of colors even after exposure to the illurainant has ceased thus

reducing ability to make accurate color judgments. Data on the extent of

sensitivity shifts and changes in color appearance are required for making

decisions about the types of lighting to be used in a building. Where transitions between different colored illuminants are experienced, for example,

the effect on color appearance is greatly increased.

In this study, laboratory experiments assessing the magnitude and

duration of shifts in the color sensitivity function following adaptation to

a variety of illuminants will be conducted. Later, a series of experiments

will be conducted to quantify the effects of the illuminants upon color

appearance. These experiments will provide basic information on the effects

of specialized illuminants upon color response in terras of changes in visual

sensitivity and in color appearance. The results of all this will provide

useful, quantitative data to the lighting practitioner. The results will

also be used in guidelines for the use of colors and various high-efficiency

light sources.

101
OPPONENT-COLOR APPROACH TO COLOR APPEARANCE

James A. Worthey

(301) 921-2177

Building Physics Division

Sponsor: National Bureau of Standards

There are only three types of color receptors in the eye, and their

spectral sensitivities are broad and smooth. Also, colored objects generally

have smooth reflectance spectra. It follows that certain broad features of

an illuminant's spectrum should be more important than the fine details.

Luminance and chromaticity are "broad features" routinely computed for lights.

The goal of this project is to define a larger set of color-rendering features

that may be calculated from simple formulas like those for chromaticity. A

logical way to do this is by the method of generalized Fourier analysis.

Within the framework of this mathematical method, enough freedom remains that

the definitions can have data regarding the eye, natural lighting, and even

common object colors worked into them. This will make the results more useful

without complicating the calculations. In fact, it is the effort to work in

data from the literature that will take up most of the time. Data regarding

color vision will appear within the method as opponent-color sensitivity

functions.

This project will show how to compute the main effects on object color

of a change in lamps, and will make more clear why color rendering is important. It will provide explicit guidance to designers of building illumination

systems.

102
DAYLIGHTING STUDIES

Stephen J. Treado

(301) 921-2758

Building Physics Division

Sponsor: National Bureau of Standards, Tri-Service, and Naval Civil

Engineering Laboratory

The type, size, and configuration of window openings have a strong

impact on building lighting, heating, and cooling loads. Daylight has been

shown to have good potential for reducing lighting energy requirements; however, the effect of daylighting schemes on building heating and cooling energy

requirements must also be considered. Since the luminous efficacy of solar

radiation is typically two to three times that of electric light sources, the

substitution of the proper levels of daylight for electric lighting can reduce

heating and cooling loads substantially, while providing psychological and

aesthetic benefits.

This year work will begin on collecting daylight availability data for

vertical surfaces under partially cloudy sky conditions; data which are virtually non-existent and badly needed. Researchers also will validate the prediction routines against measured data for a variety of fenestration systems.

Other work will improve the capabilities of prediction routines to enable

evaluation of innovative fenestration designs and complex building configurations, such as are typically found with passive solar designs. Eventually,

this project will produce a computer simulation program on daylighting/

skylighting and technical reports with recommendations for energy-efficient

daylighting practices, fenestration designs, and skylight use.

103
CtlL-l LIGHTING PROGRAM

Stephen J . Treado

(301) 921-2758

Building Physics Division

Sponsor: Naval Civil Engineering Laboratory

The Conservation of Electric Lighting computer program (CEL-1) was

developed as a tool to assist the building designer in determining energyefficient fenestration and lighting configurations. However, at its present

state of development only the lighting energy, daylight illumination, and

visual performance aspects of fenestration use can be evaluated. In addition, calculations can only be made for a single point in time (static

analysis) as opposed to the annual dynamic analysis required to determine

the impact of fenestration systems on net building energy requirements for

the entire year.

In contrast, the BLAST program can be used to perform building energy

and system loads analyses on an annual basis using hourly increments. However, the BLAST program does not consider the impact of daylighting, so it

does not allow for complete evaluation of the effect of different fenestration systems on building thermal and lighting loads and energy. This project

will result in a computer simulation program incorporating a hybrid version

of CEL-1 and BLAST to enable complete evaluation of fenestration systems on

building energy and loads.

104
THE USE OF HAZARD PICTORIALS/SYMBOLS IN MINES

Belinda L. Collins

(301) 921-2237

Environmental Design Research Division

Sponsor: U.S. Bureau of Mines

In the first phase of this project, current practice in safety symbol

signage in mines will be documented and analyzed. This includes collection

and review of existing symbols and sign systems, as well as compilation of all

applicable standards. In addition, the need for safety symbols shall be documented and categorized through visits to mines and mills, a mine-hazard analysis, review of pertinent research literature, and discussions with mine

experts. Existing practices, symbology, and standards will be reviewed and

compared to determine gaps and needs. Later, both laboratory and field-based

research methods will be developed and applied with the goal of determining

the characteristics of effective symbols under normal and reduced visibility.

A set of mine safety symbol signs will also be evaluated by a selected sample

of users at the Lake Lynn Experimental Mine Site and at another mine. A

handbook of recommendations will be prepared as a chapter in the final report.

Documentation and detailed analysis of the results from this research

program will provide the needed experimental base for hazard warnings in

mining environments. Furthermore, because the principal investigator chairs

the ANSI Z535.3 Subcommittee on Safety Symbols, CBT and BOM are in a position

to transmit the research results to the standards community and prompt more

effective hazard warnings.

105
HAZARD PICTORIAL SIGNAGE FOR SAND AND GRAVEL AND CRUSHED STONE MINES

Belinda L. Collins

(301) 921-2237

Building Physics Division

Sponsor: Bureau of Mines

Symbols used to provide emergency and safety information in building and

mining/milling environments must communicate effectively under a wide range of

visual conditions which can include poor illumination, dust, and glare. These

symbols and pictorials must be legible, conspicuous, and understandable to all

those who encounter them, even over a period of time. There is little agreement on the characteristics of symbol signs which contribute to legibility

and Gonspicuity, as well as understandability

.

This research will focus on studying the overall effectiveness of safety

symbols under in-raine conditions including poor legibility. During the inraine evaluation, physical variables such as contrast, luminance, and general

degradation will be assessed for a set of hazard pictorials at two aggregate

mines. (These mines typically have problems with dust, thus affording an

opportunity to study legibility problems first hand.) In addition, the conspicuity and understandability of the symbols will be assessed with mine

personnel following installation of the signs. A report summarizing the

analysis of symbol effectiveness in in-mine applications will be prepared.

It will document the conspicuity and understandability data as well as the

physical measurement data for the set of installed hazard pictorials.

106
BUILDING

THERMAL EQUIPMENT

Evaluating the Performance of Heat Pumps

Heat Pump and Air Conditioner Test Procedures

Examination of Non-Azeotropic Mixture Refrigerants for Heat Pumps

Refrigerant Mixture Measurements in Two-Phase Flow

Refrigerator and Freezer Studies

Water Heater Studies

Furnace, Boiler, and Household Appliance Test Procedures

Appliance Standards

Household Appliance Data Update

Thermal Test Methods — Solar Assisted Heat Pumps and Cooling Components and

Systems

Experimental Evaluation — Solar Test Cells

Technical Support to DoE

10T
EVALUATING THE PERF0R^4ANCE OF HEAT PUMPS

David Didion

(301) 921-2994

Building Equipment Division

Sponsor: Department of Energy

The Department of Energy has undertaken an extensive heat pump

development program for the past several years. The entire program involves

several million dollars annually and has the development of several prototype

innovative heat pumps as its goal. These prototypes may be segregated into

two major categories: electric and heat actuated. The machinery development

work is being conducted by several different industrial firms and the CBT

role is one of independent technical evaluation of performance. CBT will

develop the test and rating procedure under which each generic type of

prototype can be evaluated in a laboratory.

For the advanced electric heat pumps, the test and rating procedure

developed for DoE under the appliance labeling program appears to be adequate.

Under the heat-actuated heat pump category, there are two subcategories:

engine-driven heat pumps and absorption heat pumps. Under this program, CBT

has already developed a test procedure covering the engine-driven units. The

current fiscal year's efforts will focus on an evaluation procedure for

absorption heat pumps. The data produced and techniques developed are essential if the true performance of equipment operating in the field is to be

understood. This knowledge is then available for future use as the basis for

improved equipment design, life cycle costing analysis, and establishment of

minimum standards.

108
HEAT PUMP AND AIR CONDITIONER TEST PROCEDURES

David Didion

(301) 921-2994

Building Equipment Division

Sponsor: Department of Energy

The Energy Policy and Conservation Act (PL 9^-163) and the National

Energy Conservation Policy Act (PL 95-619) require the Department of Energy

to prescribe test and rating procedures and minimum performance standards for

various residential appliances, including central heat pumps and air conditioners. DoE has, since 1975, relied on CBT to assist in the development of

the test procedures. Since then, DoE has been interested in verifying these

test procedures and extending their scope to include new designs coming onto

the market. Also, since the current procedures have caused a significant

increase in the manufacturer's cost of testing, DoE is sponsoring a continuing

CBT effort to simplify the procedures through better understanding (both analytical and empiricial) of this equipment's dynamic performance. This work

encourages energy conservation affecting virtually all new-production

residential heat pumps and air conditioners in the U.S.

109
EXAMINATION OF NON-AZEOTROPIC MIXTURE REFRIGERANTS FOR HEAT PUMPS

David A. Didion

(301) 921-2994

Building Equipment Division

Sponsor: Electric Power Research

Conventional vapor-compression heat pumps employ single-component

refrigerants or azeotropic mixtures (those which have a single boilingcondensing temperature-composition phase diagram) as their working fluid. The

use of non-azeotropic mixtures as the working fluid offers at least three potential energy performance advantages without major changes in the manufacturing

process of existing heat pumps. These advantages are an improved capacity-topower ratio, a reduction in irreversibilities in the heat exchangers, and an

increase in capacity at lower evaporator temperatures. The quantification of

each of these advantages can be estimated theoretically; however, the costeffectiveness of the design changes can only be done by optimization studies by

manufacturers who are thoroughly familiar with manufacturing costs. A tool for

predicting the energy performance as well as the operating costs of a design is

the simulation model being developed in this study.

110
REFRIGERANT MIXTURE MEASUREMENTS IN TWO-PHASE FLOW

David A. Didion

(301) 921-2994

Building Equipment Division

Sponsor: National Bureau of Standards

The conveotlve heat transfer coefficient is the single most important

property for the design of heat exchangers. For those heat exchangers which

have internal boiling or condensation coupled with forced convection (e.g.,

refrigerant systems, steam power systems), the complexity of flow conditions

are such that coefficient values are normally completely empirically based.

Since this study focuses on binary mixtures which are non-azeotropic (different boiling/condensation points), the problem is complicated even further.

In single-component fluids it is typical to establish an empirically based

functional relationship between the convective heat transfer coefficient and

the other transport properties (e.g., conductivity, visocity) for a given

range of flow patterns and thermodynamic conditions. Once these relationships

are established for categories of fluids, it is possible to predict the heat

transfer coefficient based on the measurements of other transport properties

that are significantly easier to make. In the area of nonazeotropic mixtures,

virtually no such relationships among the transport properties exist.

The specific group of fluids that will be studied are fluorocarbons that

are used or intended to be used as refrigerants. The apparent advantages of

using non-azeotropic mixtures in refrigerant systems are improvement in efficiency, less environmental (ozone) impact, multi-level evaporators, and selflubricating working fluids. The evaluation of any of these possible advantages

entails an overall performance evaluation of the refrigerant system, which in

turn requires knowledge of the transport properties of the refrigerant.

The heat transfer data and relationships that evolve from this study

will be used by researchers in the refrigeration industry to quantify the

advantages of binary mixtures in their future refrigeration systems design.

Also, it will provide CBT with a measurement facility that is equally

applicable to the wide variety of binary mixtures found in chemical plants.

Ill
REFRIGERATOR AND FREEZER STUDIES

Robert A. Wise

(301) 921-2935

Building Equipment Division

Sponsor: Department of Energy

DoE's effort in energy use labeling for household appliances requires

that they have standard test procedures for accurate determination of energy

efficiency, that the procedures are repeatable, and the procedures are not

burdensome to perform. The objectives of this project then are to expand or

modify the DoE test procedures for refrigerators and freezers where required

and to provide laboratory data, analyses, and recommendations related to the

new tests.

1 12
WATER HEATER STUDIES

James E. Harris

(301) 921-2935

Building Equipment Division

Sponsor: Department of Energy

The Energy Policy and Conservation Act (PL 94-193) has mandated that

household appliances, including water heaters, be labeled for energy use

using standardized testing methods. Thus, it is necessary to establish

standard test procedures that allow the accurate determination of energy

efficiency, are repeatable, and not burdensome to perform. The objectives of

this project are to expand and/or modify the DoE water heater test procedures

where required and to provide laboratory data, analyses, and recommendations

related to the test procedures.

113
FURNACE, BOILER, AND HOUSEHOLD APPLIANCE TEST PROCEDURES

Esher R. Kweller

(301) 921-2935

Building Equipment Division

Sponsor: Department of Energy

This project will provide industry, via DoE, with an equitable testing

and rating procedure for determining the seasonal energy performance of central residential furnaces and boilers. The Energy Policy and Conservation

Act (PL 9'+-193) and the National Energy Conservation Policy Act (PL 95-619)

require the Department of Energy to prescribe test and rating procedures and

minimum performance standards for various residential appliances, including

furnaces and boilers. DoE has, since 1975, relied on CBT to assist in the

development of these procedures. A draft test and rating document for furnaces and boilers was delivered to DoE in 1977. Final publication in the

Federal Register was in May 1978. Since then, DoE has been interested in

expanding the procedures to include new furnace designs coming on the market

(i.e., condensing units) and adapting the test procedures to fit unusual

designs (i.e., sealed combustion installations). During the course of this

development, CBT has supported DoE in defending or modifying the procedures

according to suggestions made by industry, who were concerned about every

detail since virtually every furnace or boiler model sold in the United States

will nave to be rated in accordance with these procedures. This work will

encourage energy conservation through the production of more efficient

furnaces, boilers, and household heating equipment for residential space

heating.

114
APPLIANCE STANDARDS

Joseph Greenberg

(301) 921-3293

Building Equipment Division

Sponsor: Department of Energy

The Energy Policy and Conservation Act as amended by the National Energy

Conservation Policy Act has mandated that national minimum efficiency standards be established to reduce energy usage. The legislation gives priority

for establishing standards for eight products including refrigerators, freezers, room air conditioners, central air conditioners, furnaces, water heaters,

clothes dryers, and kitchen ranges/ovens. Standards for the remaining product types are then to be established. These standards are crucial to the

nation's goal of lower energy consumption. Technical support will be provided

to DoE in their effort for developing energy efficiency standards for

appliances.

115
HOUSEHOLD APPLIANCkl DATA UPDATE

Joseph Greenberg

(301) 921-3293

Building Equipment Division

Sponsor: Department of Energy

The Energy Policy and Conservation Act as amended by the National Energy

Conservation Policy Act requires the development of test pocedures, labeling

rules, and energy efficient standards for consumer appliances. These requirements must be established using representative data when reflecting such items

as energy efficiency, energy use, etc. Many of the parametric values used in

the initial rulemaking have changed due to energy price increases, changed

consumer behavior, availability of more efficient appliances, etc. This project will develop the data needed to update the various rules promuglated by

the Energy Conservation Program for Consumer Products using the most

currently available data.

116
THERMAL TEST METHODS ~ SOLAR ASSISTED HEAT PUMPS AND COOLING COMPONENTS AND

SYSTEMS

Kent A. Reed

(301) 921-3465

Building Equipment Division

Sponsor: Department of Energy

This task draws on previous efforts in solar equipment and building

equipment to develop viable test methods and evaluation procedures for solarassisted heat pumps and solar cooling components and systems. Based on reviews

of the work performed at CBT and elsewhere, as well as the eixsting industry

consensus standards issued by ASHRAE and the Air-Conditioning and Refrigeration Institute (ARI), modified test methods and evaluation procedures will be

drafted. Bench tests on candidate equipment will be conducted to verify the

draft methods and to provide performance data for checking the evaluation

procedures. An interagency report will be prepared for the sponsor summarizing the recommendations for test and evaluation procedures for these solar

components

.

117
EXPERIMENTAL EVALUATION — SOLAR TEST CELLS

Bal M. Mahajan

(301) 921-3293

Building Equipment Division

Sponsor : Department of Energy

The objective of this project is to acquire data for use in

1) establishing performance monitoring procedures for passive solar heating

and cooling systems; 2) performance characterization of various passive subsystems (e.g., clerestory, direct gain, sunspace, and collector/storage wall);

3) detailed passive solar building energy analysis and algorithm validation.

Determination of the thermal performance of passive solar-heated and cooled

buildings is important for designers and consumers to improve building energy

efficiency, and for the Federal and State Governments to develop fair and

effective regulatory and incentive programs. Passive solar thermal performance

is inseparable from building thermal performance, which is complex and as yet

not fully understood. Its determination can require instrumentation and analysis techniques. Improving consistency and uniformity will make performance

evaluation results more credible to designers and consumers and more useful in

estimating relative benefits between designs.

A passive solar test facility, for Class A level monitoring, has been

constructed at the NBS annex in Gaithersburg , Maryland. This test facility

has been especially designed to be reconfigurable so that different passive

hybrid designs can be installed with minimum cost and effort. The current

configuration hosts a direct gain cell, a control cell (i.e., no passive

features), a trombe wall cell, and a cell housing the data acquisition system

and a component testing calorimeter. The test facility has been operational

since October 1981 with the direct gain cell completely instrumented and the

control cell and trombe wall cell only minimally instrumented. Preliminary

performance data for the direct gain cell for three different time sequences

and test conditions have been gathered, reduced, and distributed to the

participants of the Class A monitoring program.

Continuous air infiltration measuring equipment will be procured and

installed at the test facility, and the instrumentation of the trombe cell

will be completed. Carefully measured performance data for selected time

sequences and test conditions will be acquired, reduced, and distributed to

the participants of the Class A monitoring program.

118
TECHNICAL SUPPORT TO DoE

Robert Wise

(301) 921-2935

Building Equipment Division

Sponsor: Department of Energy

The Energy Policy and Conservation Act provides for the granting of

waivers from testing for products which cannot be tested in accordance with

the currently prescribed DoE test procedure. For DoE to respond to petitions

from manufacturers for wavier, DoE must first resolve the question of applicability of currently prescribed test procedures to the products in question and

then decide if waivers are to be granted or if testing under present test procedures is in order. CBT will provide DoE with the technical bases to make

such decisions.

119
MECHANICAL SYSTEMS

AND CONTROLS

Systems and Controls Laboratory

Controls Dynamic Modeling

Energy Monitoring and Control System Measured Performance

Energy Analysis of Control Strategies

Energy Monitoring and Control System Algorithms

Unsteady Hydraulics of Branch Drains and Soil Stacks

Existing Building Wiring Systems

Air Quality Criteria for Archival Storage

120
SYSTEMS AND CONTROLS LABORATORY

George E. Kelly

(301) 921-2144

Building Equipment Division

Sponsor: National Bureau of Standards

The focus of this program will be developing mathematical models and

measurement techniques for evaluating the performance of building systems and

controls, encouraging energy conservation in buildings through improved control strategies and software, and developing guidelines for automated building management systems. This research effort will complement CBT's current

DoE-sponsored research program aimed at documenting the energy saving potential of the most commonly employed HVAC control strategies, developing algorithms for building control systems, evaluating the reliability of automated

building management systems, and studying the application of sensors in

energy monitoring and control systems.

This year's effort will involve the development of a second-generation

building/HVAC/control system simulation program for evaluating systems

dynamics, algorithms, and strategies; the completion and use of an HVAC Test

Facility for verifying and refining models and control algorithms; and the

partial installation of CBT's own Energy Management and Control Systems in

Building 101. Ultimately, the results of this work will be incorporated in

future concensus standards, guide specifications, and design/operating aids

for building designers, owners, and operators.

121
CONTROLS DYNAMIC MODELING

George E. Kelly

(301) 921-2144

Building Equipment Division

Sponsor: U.S. Navy and Department of Energy

None of the building simulation programs (e.g., BLAST 2, DOE 2) in

existence today account for HVAC control dynamics. As a result of this,

there exists very little reliable data on the amount of energy waste in

buildings due to control dynamics and absolutely no information on how to

design and operate building control systems to optimize dynamic performance.

This project will concentrate on developing simulation models that can be

used to predict the dynamic, "minute-by-minute" performance of control systems for building air handlers and heating/cooling plants. This will cover

controls for the most common types of HVAC systems and build upon on-going

CBT research to develop simulation models for building equipment and systems.

Research in future years will involve building dynamics, heating/cooling

plant dynamics, and the simulation of the entire building/HVAC/control systems. New dynamic models and the information developed on HVAC/systera control

dynamics will lead to better building control system design.

122
ENERGY MONITORING AND CONTROL SYSTEM MEASURED PERFORMANCE

C. Warren Hurley

(301) 921-3839

Building Equipment Division

Sponsor: U.S. Navy

This project will help the Navy in studying and improving the performance

of EMC systems installed at naval facilities. Between 30 and 70 percent of

the EMC systems installed in the U.S. are unreliable. This is due to many

factors; one of the most significant problems is lack of knowledge by field

personnel on how to purchase, install, calibrate, and maintain sensors and

measurement instrumentation. Under this project, procedures for calibrating

and verifying the accuracy of EMCS sensors in the field will be completed, and

guidelines for the field calibration of building humidity, flow, and temperature sensors will be published. A sensitivity study on typical sensor errors

will be completed and presented as an EMCS conference paper. Assistance will

be provided the Navy in the review of work completed by an independent contractor in the development of an EMCS Inspection Testing Device. A study will

also be undertaken to evaluate and document the effect of some typical HVAC/

sensor/control system interactions on building energy consumption. Some typical interactions which might be investigated are: the effect of cooling coil

throttling range on heat systems using economizer cycles; the application of

economizer cycles to duel duct, multi-zone and variable air volume systems;

the effect of pressure sensor error on the energy consumption of variable air

volume systems; the retrofit of constant volume systems to VAV systems and

correct pressure sensor location; and the effect of temperature sensor error

on the control of hot and cold decks in multi-zone systems.

123
ENERGY ANALYSIS OF CONTROL STRATEGIES

James Kao

(301) 921-3844

Building Equipment Division

Sponsor: Department of Energy

A study is urgently needed to independently document the potential energy

savings of different commonly used strategies. In FY82 , CBT used the computer

program BLAST 2 to evaluate control strategies for a variety of HVAC systems

in a large office building and a large retail store in different regions of

the country. Typical strategies studied were dry bulb economizer cycle,

enthalpy economizer cycle, hot and cold deck temperature reset, zone control,

floating space temperature, and scheduled setback. In FY83, this work was

extended to cover control strategies for one additional building type (an

education building). The building's performance is being simulated for several different types of HVAC systems and for seven different geographical

locations, representing typical U.S. climatic regions. This study will encourage energy conservation by providing design engineers and building owners with

factual information on the benefits of the most commonly employed control

strategies. It will also lay the groundwork for the future development of an

advanced analysis tool for evaluating control dynamics and advanced control

strategies.

124
ENEflGI MONITORING AND CONTROL SYSTEM ALGORITHMS

William B. May

(301) 921-3839

Building Equipment Division

Sponsor: U.S. Navy and Department of Energy

At present, there are no standardized, nonproprietary EMCS application

algorithms available for use by companies entering the building controls field.

Many of these companies lack training and experience in HVAC systems, building

controls, and algorithm development. As a result, the building owner or manager who purchases their system is often stuck with an EMC system that either

doesn't work or only partially works.

To assure a minimum level of performance of EMC systems, CBT plans to

develop public-domain algorithms for HVAC/building applications. Work will

concentrate on the completion of algorithms for the control of building air

handlers, including optimal start/stop, scheduled time of day stop/start,

duty cycling, demand limiting, temperature reset, and economizer cycle. In

the second half of FY83 , this effort will be expanded to development of

algorithms for the control of heating and cooling plants.

The development of public domain algorithms for EMCS systems should

greatly improve their performance, especially for systems made by small manufacturers, and lead to increased energy conservation in commercial buildings.

Specification of such algorithms will help to assure that future energy measurement and control systems provide at least this minimum level of

capability.

125
UNSTEADY HYDRAULICS OF BRANCH DRAINS AND SOIL STACKS

Lawrence S. Galowin

(301) 921-3293

Building Equipment Division

Sponsor: National Bureau of Standards

The investigation of flows at the junctions between multistory drainage

stacks and horizontal branches requires experimental measurements to determine inlet characteristics and the subsequent pipe flow conditions. Testing

was begun during FY 1982 to provide soil stack exit and junction boundary

conditions for later mathematical modeling. Numerical solutions of the flow

equations of continuity and momentum as a function of dynamic load are to be

obtained by expansion of the computer program for partially filled pipe flows,

upstream and downstream of junctions; computations from the expanded program

will be compared with experimental results.

The results will provide model plumbing code officials and plumbing

design engineers with a new basis for code requirements and analysis of plumbing drainage systems. Traditional plumbing code requirements and design practices are based upon overly conservative tabulations of permissible pipe size

loading tables derived from empirical factors for the hydraulic capacity. The

American Society of Plumbing Engineers Data Book, "Fundamentals of Plumbing

Design," does not provide an analytical technique for determining pipe size

and slope for drains with low-water-usage fixtures. Dissemination of CBT

reports and articles for inclusion in the Data Book can establish a broad

capability to conduct trade-off studies to optimize drainage system installations, and through computer-aided graphics permit rapid determination of the

performance of design variations.

126
AIR QUALITY CRITERIA FOR ARCHIVAL STORAGE

Robert Mathey

(301) 921-2629

Building Materials Division

Sponsor: General Services Administration

The National Archives Building, which houses many of the nation's basic

documentary materials, was constructed in the early 1930 's and was one of the

first buildings in Washington to provide all-season environmental control.

The controlled environment was prescribed to protect the nation's valuable

records from the effects of extreme temperature and relative humidity, and

from pollutants such as sulfur dioxide and nitrogen oxides. The original

system, although designed to meet these objectives, has been modified over the

years and has had a history of less-than-satisfactory performance.

Under this project, CBT will measure pollutants in the air at selected

locations in the stack area of the National Archives Building to determine

baseline performance of the existing environmental control system. Measurements will also be made in other buildings. Existing data of temperature and

relative humidity conditions in the spaces used for records storage will be

reviewed and additional data taken, if necessary, to determine current

performance for thermal and humidity control.

A search will be made to determine the most up-to-date standards and

"operating procedures" used in the design and maintenance of records storage

facilities. Experts in the field of gaseous and particulate pollutants will

be consulted to obtain their advice on the availability and acceptability of

existing standards or the need to establish new limits for contaminates that

accelerate degradation of historic artifacts and records. As a result of the

investigation, criteria will be drafted for review by the National Archives

v/hich give recommended limits for control of environmental conditions. These

criteria could be used as the basis for a GSA contract for upgrading the

mechanical system of the building.

127
EXISTING BUILDING WIRING SYSTEMS

Thomas K. Faison

(301) 921-3465

Building Equipment Division

Sponsor: Consumer Product Safety Commission

Existing wiring systems do in fact exceed the National Electric Code

temperature limit of 60 °C when covered with thermal insulation. The Consumer

Product Safety Commission is concerned that long-term exposure to elevated

temperature may pose a safety hazard for branch circuit wiring in homes. Following recommendations developed through an associated effort with CPSC, specimens of aged wire (rubber, polyvinyl chloride, armored cable, nonmetallic

sheathed, and single strand) were identified. The ages of specimens' were

divided into three categories: pre 19^0, 19^0-1960, and post-1960. Before

1910, the wire was primarily rubber coated. From 1910 to I960 there was a

transition from rubber to PVC and since I960 almost all production has been

PVC. The Underwriters Laboratories under contract to CBT has been conditioning and testing the specimens, provided by CBT. The specimens are being conditioned at 60°, 75°, and 90°C. Measurement of tensile strength and elongation are made as a function of time and temperature. The data will be

analyzed to determine if trends can be identified for the types of wire covering as the specimens are aged under the described conditions. If the data and

the analysis produce results to indicate that at 60° C the dielectric insulating

material is losing critical physical properties, a basis will exist for making

recommendations for a code change.

<r U.S. GOVERNMENT PRINTING OFFICE: 1983-380-997/5117

128



U.S. DEPARTMENT OF COMMERCE

National Bureau of Standards

National Engineering Laboratory

Center for Building Technology