Contents

国総研ニューズレター

N I L I M N e w s L et t e r■ Result of Full-scale Fire Experiment of a Three-story Wooden School Building■ Promoting Research to Mitigate Congestion Through Cooperation between Advanced Vehicle
Technology and Road Infrastructure■ Revision of “Specifications for Highway Bridges”■ Development of Life Cycle Environmental Assessment Methodology for Infrastructures-How to calculate CO2 emissions from construction■ 50th Estuarine, Coastal and Shelf Association (ECSA) Conference■ Research on traceability technology for ready-mixed concrete with IC-Tags

No.41

Summer 2012
Result of Full-scale Fire Experiment of aThree-story Wooden School Building
Building Department, Fire Standards Division
In order to revise the Building Standards Law, a fire experiment(preliminary experiment) using a three-story wooden school building
has been conducted.
On February 22 of this year, a preliminary experiment to prepare fora full-scale fire experiment using a three-story wooden school building
was carried out in the presence of many observers on the grounds of theNILIM (purpose and plan were already reported in News Letter No. 39).
The experiment started with the ignition of the fire in the first storyteachers’ room at 9:00 a.m., then about 2 minutes and 50 seconds afterignition, flames burst out of an opening in the room where the fire started,and at about 5 minutes and 20 seconds after ignition, the fire had spreadthroughout the entire room. From the story where the fire started, it spreadthrough exterior openings to the upper stories at a relatively early stage (tothe second story at about 3 minutes 30 seconds after ignition and to thethird story at about 6 minutes 20 seconds after ignition). The timber frame
construction part in the room where the fire started collapsed at about 76
minutes after ignition, followed by the collapse of the wood frame structure
part at about 95 minutes after ignition and of the fire walls at 96 minutes
after ignition (there was a delay between the start of the fire and its spread).
This preliminary experiment, which was an experiment of unprecedented
scale, provided valuable data used to evaluate the spreading routes, state

Promoting Research to Mitigate Congestion
Through Cooperation between Advanced
Vehicle Technology and Road Infrastructure
Research Center for Advanced Information Technology,
Intelligent Transport Systems Division
To mitigate congestion at sag section, where about 60% of congestion
occurs on expressways, the ITS division and auto makers are working
together to formulate new congestion countermeasures by harmonizing
advanced automobile technologies with roadside infrastructure.
Drivers may drive in the overtaking lane because they are eager to drive
faster to keep up with the increasing traffic flow rate. At sag sections,where the gradient of the road changes gradually from a descending toan ascending slope, driving speed tends to slow because drivers may
not realize the gradient is changing. This slowdown may cause headway
fluctuation, disturbing the traffic flow and causing traffic congestion. This
process is considered to be the mechanism of congestion at sag sections.
Therefore, drivers should keep the following time-gap stable and eachlane should be used at the same rate to achieve a stable traffic flow. Since
2010, NILIM and auto makers have been conducting a series of research
projects to formulate new ITS services to mitigate traffic congestion atsag sections: 1) Roadside detectors detect the possibility of congestion
occurring. Then the ITS Spots provide information suggesting how toof collapse, and the impact of the heat on the building’s surroundings:
factors which could not be learned without a full-scale experiment, and also
confirmed the way that sparks were scattered. The fire spread through afire wall at about 18 minutes after ignition on the first story, confirmingthat fire doors installed in fire walls are opened by the increase in pressure
inside a room during the early stage of a fire. An outline of the experimentalbuilding and reported results including typical temperatures inside itsrooms, and video recordings have been published on the NILIM web site.
After adjusting the specifications and experiment methods in light of
the results of this preliminary experiment, a full-scale fire experimentwill be performed based on building specifications which, it is predicted,
will be standardized in 2012.

View 34 minutes after ignition, when the fire had spread to the entire building.

http://www.nilim.go.jp/lab/bbg/kasai/h23/top.htm

drive (e.g. to keep the following time-gap stable, or not to drive in the outerlane). 2) ACC (adaptive cruise control) equipped vehicles might be able tomove appropriately to mitigate congestion at sag sections because theirfunctional features make the following time-gap consistent with that set
by the driver The potential of these services to mitigate traffic congestion
were examined by traffic simulations and field operational tests.
This year, to conduct research in depth to make the services morefeasible, driving tests will be carried out on public roads in order toverify the extent to which ACC vehicles and ordinary vehicles (not ACCequipped) maintaining following time-gap and whether complying withthe rule to keep to the left (outer) lane impacts the surrounding traffic flow.
The ITS World Congress will be held in Tokyo in 2013 and demonstrationsof these services will be given for delegates to the congress.

View of Test Drive on the NILIM Test Track1

Revision of “Specifications for
Highway Bridges”
Road Department, Bridge and Structures Division
In February 2012, the technical standard for highway bridges,“Specifications for Highway Bridges”, was revised for the first time inabout 10 years. This revision completes maintenance related provisions
based on the recent state of highway bridges at the same time as it
reflects the results of research conducted since the previous revision.
Highways are the most basic public infrastructure supporting thelives and the economic activities of the people. During large-scaledisasters such as the Great East Japan Earthquake of 2011, we have been
reminded of the vital roles they play as infrastructure which supports
rescue, recovery, and restoration activities. Japan now has highway
bridge assets equal to about 650,000 bridges. And bridges 15m longor longer (about 160,000 bridges) are aging rapidly, with about 30%
completed more than 40 years ago, and about 50% completed more than
30 years ago. This has been accompanied by increasing damage caused
by deterioration over time. This includes severe damage such as broken
diagonal bridge bracing in steel truss bridges , severe fatigue cracking
of steel main girders, and breakage caused by corrosion of prestressed
concrete bridge tension members. Maintaining this vast quantity of roadassets in good condition for a long period of time under present tightfinancial conditions is a major challenge facing society. Consequently,
it is necessary that newly built bridges be serviced in the future on thepremise that they will be maintained while efforts are made to reduce
maintenance and operation costs through countermeasures such as
preventive maintenance of highway bridges.
This revision to the “Specifications for Highway Bridges” is,considering the above circumstances, focused on certainty and easein bridge maintenance. The revised technical standard is required to
avoid factors which make maintenance difficult. And in this connection,
provisions concerning the maintenance equipment necessary forscheduled maintenance during bridge’s service period in the design
were stipulated.
And because it is recognized that these kinds of information areimportant for measures to diagnose, repair, or reinforce damage toexisting bridges, it is clearly stipulated that various information on
bridges from design stage to construction stage must be preserved toutilize the information at the maintenance stage.
For the design stage, bridge design considering the impact ondamage to overall bridge structure caused by the loss of the functionsof some members was stipulated. In response to the collapse of a decktruss bridge in the United States in 2007 and damage of major bridge
members in Japan.
In addition, this revision reflects the achievements of surveys andresearch conducted in various fields since the previous revision, forexample, revising steel slab thickness allowance in friction connection
joints with high tension bolts, quality control of construction the Design
Earthquake Ground Motion, and so on.

Development of Life Cycle Environmental
Assessment Methodology for Infrastructures-How to calculate CO2 emissions fromconstruction-

Set based on plan and
Set based on thedesign documents etc. environmental load
prepared by project unit table developed
operatorsby the NILIM

Environment Department, Road Environment Division
Life Cycle Assessments (LCA) for infrastructure can assess thecarbon dioxide (CO2) emission from construction works by organizing
quantities written on planning and design documents at each decisionmaking stage (planning, designing, constructing, and materialselection) of a public infrastructure provision project.
The infrastructure LCA developed by the National Institute forLand and Infrastructure Management (NILIM) is an environmental
assessment technology developed to calculate the CO2 emissions fromvarious construction works including infrastructure construction. The
CO2 emissions calculation method is basically to sum up products of“quantities” of materials or work etc., which can be organized based onplanning and design documents, and their respective “environmentalload units (CO2)”.

The provision of infrastructure is conducted by the following
procedure: [1] planning an overall project at the planning stage, then[2] deciding forms of structures at the designing stage, and [3] detailed
construction methods at the constructing stage, and finally by [4]selecting each material according to each construction method.
In order to assess CO2 emissions by an infrastructure, it is necessary
to develop a method applicable to each decision-making stage, but thetypes of quantities organized based on planning and design documents
etc. differ at each decision-making stage. In the case of road construction,

2

Quantity

Load unit

Unit
Materials 1

X1t

E1
3

CO2
emissionsUnit
t-CO2/t

X1×E1
3

Materials 2

X2

m

E2

t-CO2/m

X2×E2

Construction
machinery 1

X3

Machines/.day

E3

t-CO2/Machines
/.day

X3×E3

Fuel 1

X4

m3

E4

t-CO2/m3

X4×E4

…

…

…

…

…

…

CO2 emissions of projects and buildings whose totals are assessed

Image of the calculation of CO2 emissions based on theinfrastructure LCA

the used load unit differs at each stage: at the planning stage it is thelength of each type of road (earthwork road, bridges, tunnels etc.) and at
the constructing stage it is the quantity of materials or the days of use ofconstruction machinery.
The NILIM has developed “formulas” and “environmental loadunits” for all decision-making stages, and at the same time, has devised“unifying system boundaries” of formulas and load units to permit
comparisons of calculation results at different stages.
http://www.nilim.go.jp/lab/dcg/lca/top.htm

50th Estuarine, Coastal and Shelf
Association (ECSA) Conference
Coastal, Marine and Disaster Prevention Department,
Coastal Zone Systems Division
Our researcher won the “Best Student Oral Presentation Award” for apresentation of research results given at the Fiftieth ECSA Conference.
The 50th ECSA Conference, “Today’s science for tomorrow’s
Management”, sponsored by ECSA and Elsevier was held in Venice inItaly from June 3 to 7, 2012.
This conference was held to gather the most advanced scientificknowledge about coastal region environments and ecosystems.
Researchers from various countries presented the results of theirresearch work by giving 389 oral presentations and displaying 238
posters.
We presented the results of two research projects titled, “Numericalestimation of floating macro-debris inflow flux into Tokyo Bay” and“A new technique for detecting colored plastic debris on beaches using
webcam images and CIELUV”. Researcher Kataoka, a doctor course
student at the Toyohashi University of Technology and a member ofour division was awarded the Best Student Oral Presentation Awardfor presenting these two reports.
Photos: (Top) View of the 50th Estuarine, Coastal and Shelf Association(ECSA) Conference and (Bottom) Commemorative Photo Taken afterAward Presentation

Research on traceability technology forready-mixed concrete with IC-Tags
Housing Department, Housing Production Division
We have conducted joint research on technology to ensure thetraceability of concrete by embedding IC tags containing information
about its production and its qualities inside ready-mixed concrete.

The application utilization time measured inside an actual readymixed concrete production plant was about 70 seconds. There were noserious problems operating the system, and the experiment results showthat the time load is small and it is a feasible system.
As results of the joint research, we have confirmed the systemthrough a survey at the same time as we have summarized remaining
challenges and prospects.
http://www.nilim.go.jp/lab/idg/index.htm

Ready-mixed concrete product made using illegal unauthorizedmaterials was shipped and executed in 2008, causing problems for somebuildings and increasing the need for traceability.
IC tags were already introduced in the food products
industry as a tool permitting visualization of informationsuch as what kinds of materials, methods, and processes
were applied to make a product. This use is counted on
to encourage safe and secure purchasing. Aware of thisuse, universities and industry organizations began joint
research intended to study the technical challenge ofensuring traceability of ready-mixed concrete using ICtags.
First, experiments to confirm the communication
performance of IC tags embedded inside concrete weredone using full-size specimens shaped like columns andslabs. The results have shown that even ordinary IC tags
sold on the open market can transmit if they are within
25 to 30cm of the surface of the concrete. In response tothe results, with the cooperation of industry organizations,a traceability system using IC tags achievable at thistime has been proposed and a prototype application has
been developed experimentally in compliance with thisproposal.
Photo 1. Full size specimens being prepared

Photo 2. Full-size specimens

Photo 3. View of experiments in a readymixed concrete production plant3

Schedule of Principal Events (November-December, 2012)
Scheduled Dates

Event Name

November. 10Open House (Public Works Day)

November. 14

The 10th Environmental Research Symposium

December. 42012 Conference of the National Institute for Land and Infrastructure Management

RESEARCH REPORT of National Institute for Land and Infrastructure Management (May-July, 2012)
No.
50

Title of Paper
A Consideration for Precision Improvement of Official Port Cargo Statistics in the World

Names of Divisions
Port Planning Division
Port Systems Division

TECHNICAL NOTE of National Institute for Land and Infrastructure Management (May-July, 2012)
No.

Title of Paper

Names of Divisions

668 The present situation of the road cave in sinkholes caused by sewer systems(FY2006~FY2009)

Wastewater System Division

675

Study of effects on tsunami evacuation safety of the mitigation measures and research of theevacuation building location method

Coastal Disaster Prevention Division

676

Comparative analysis of berth occupancy rateof the world’s leading container terminal by using AIS data

Port Planning Division

677

Damage and Recovery Process of Industries and Logistics in Port Cities Caused by the Great
East Japan Earthquake

Port and Harbor Department

678

Study on International Air-Cargo Traffic from/to East Asia

Airport Planning Division

679

Portfolio analysis of customer satisfaction survey on Airport Terminal

Airport Terminal Division

680 Report on Damages of Pavement at Sendai Airport due to 2011 Tohoku Region Pacific Coast
Earthquake

Airport Department

681

Airport Facilities Division

Effect of Rehabilitation Design Methods on Overlay Thickness of Airport Asphalt Pavement

682 The data analysis regarding the warning and evacuation information against sediment-related Erosion and Sediment Control Divisiondisaster
686 Manual on hydrologic and sediment measurements on mountainous river

Erosion and Sediment Control Division■ Visit the following website for documents published by the NILIM:（http://www.nilim.go.jp/lab/bcg/siryou/index.htm）■ NILIM research activities and achievements are now available on the following website as NILIM Annual Report 2012:（http://www.nilim.go.jp/english/annual/annual2012/ar2012e.html）

National Institute for Land and Infrastructure Management
Ministry of Land, Infrastructure, Transport and Tourism

No.41

Summer 2012

Asahi 1, Tsukuba, Ibaraki, 305-0804, Japan(Tachihara) Tachihara 1, Tsukuba, Ibaraki, 305-0802, Japan(Yokosuka) Nagase 3-1-1, Yokosuka, Kanagawa, 239-0826, Japan
TEL:+81-29-864-2754 FAX:+81-29-864-4322
Edited and Published byhttp://www.nilim.go.jp/english/eindex.htm
National Institute for Land and Infrastructure Management

国 総 研 ニ ューズ レ ター

NILIM News Letter