thThe 14 World Conference on Earthquake Engineering
October 12-17, 2008, Beijing, China

WEBGIS SIMULATOR FOR PROMOTION OF SEISMIC RETROFITTINGAND COMMUNITY DISASTER MITIGATION ACTIVITIES
1

2

1

3

4

J. Tobita , N. Fukuwa , M. Mori , H. Sakaue , H. Takahashi and T. Hanai
1

5

Associate Professor, Graduate School of Environmental Studies, Nagoya University, Nagoya, Japan
2
Professor, Graduate School of Environmental Studies, Nagoya University, Nagoya, Japan3
Falcon Corporation, Nagoya, Japan
4
Oyo Corporation, Chubu Branch, Nagoya, Japan
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President, Ebisu Building Laboratory, Tokyo, Japan
Email: tobita@sharaku.nuac.nagoya-u.ac.jp, fukuwa@sharaku.nuac.nagoya-u.ac.jp,
m.mori@sharaku.nuac.nagoya-u.ac.jp, hsaka@fal.co.jp, takahashi-hiroto@oyonet.oyo.co.jp,
hanai@ebi-ken.co.jp

ABSTRACT :One of the most important aspects of disaster mitigation in urban areas is the preparations residents take tomake their own houses, towns and their living environments safer. This paper describes a newly-developed
information system dedicated to promoting such actions and describes its application to the community disastermitigation practices of the residents themselves. The system is based on a simulator that provides realistic
scenarios, based on actual seismic hazards, in order to help each resident gain awareness of his/her own hazard
level, and to comprehend the need and methodology for preparations. The simulator is built around a web-based
online geographic information system (WebGIS) and integrates a series of subsystems to provide features
including a high-resolution hazard map system capable of making three-dimensional birds-eye overviews, asystem for evaluating earthquake ground motion at a specific location as well as a system for simulating theearthquake effects and the possible collapse of a wooden house at the site, including risks of falling indoor
furniture. Furthermore, to provide additional information on seismic hazards and disaster mitigation, various
related programs that utilize online systems including WebLog, Wiki and other interactive interfaces have been
incorporated. The system is also designed to assist user-groups that want to discuss and make preparations
against disasters. The WebGIS-based system also makes it possible for user-groups to create and maintain theirown disaster maps, and use those maps for disaster mitigation activities in their community. The system isalready in use by various local communities and continuous development is projected.
KEYWORDS:

Hazard maps, Wooden house, Geographic information system, E-learning, Workshops

1. INTRODUCTION
In seismically active areas, it is impossible to protect people without making efforts to mitigate earthquake
damage. As the greatest amount of damage resulting from earthquakes has historically been caused bycollapsing buildings, it is necessary to make buildings as safe as possible, as soon as possible. Ideally, this is the
responsibility of building engineers, but since most buildings are private assets, the effectiveness of a building’s
retrofit also depends on the level of each resident’s awareness.
Disaster mitigation can be considered from the following four viewpoints: people, knowledge, possessions, andmoney. For example, the promotion of seismic retrofitting requires the development of resident awareness(people), the establishment of laws and systems that promote seismic retrofitting (knowledge and systems), thedevelopment of inexpensive and effective reinforcement methods (possessions and technology), and thecreation of programs and economic incentives (money). The most important and difficult factor is the creationof awareness, especially in developed countries, because other three viewpoints have almost overcome in suchcountries. To develop resident awareness, it is important to train leaders tasked with the dissemination of
information (people), develop effective methods for dissemination of an effective education curriculum for

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The 14 World Conference on Earthquake Engineering
October 12-17, 2008, Beijing, China

disaster prevention (knowledge), create educational materials for dissemination (possessions), and convince
people that the process is affordable (money).
However, because the number of disaster prevention experts is relatively small, it is difficult to reach eachresident directly. This is because, as shown in Figure 1, the development of each resident’s awareness requires
not only the cooperation and efforts of various experts; the participation of mediators that have the ability tocontact local residents is also needed. (These include volunteers, community leaders, non-profit organizations,mass media, teachers, cooperatives, enterprise groups, and student circles.) To motivate such people toparticipate in disaster prevention activities, it is necessary to cultivate awareness and create environments where
the mediators can actively assist in the development of resident awareness. One way to create such anenvironment is to develop useful educational materials.
Disaster prevention activities start with the awareness of one’s own risks regarding earthquakes. If people areaware of the risks they face, they can learn the causes of such risks and find ways of avoiding them. At thatpoint, each organization or family can plan and implement countermeasures. After that, it is a good idea torepeat the PDCA (Plan-Do-Check-Action) cycle as shown in Figure 2. The difficult part is creating anenvironment where people can become fully aware of how earthquakes occur. This step requires the efforts ofpeople who can motivate residents into obtaining a proper level of awareness as well as the production of usefuleducational materials. In response to that need, this paper describes a newly-developed information systemdesigned to promote such actions, and describes their applications to the community disaster mitigation
practices by the residents themselves.
Awareness

EXPERTSMEDIA & MEDIATORS

Universities
Researchers
Engineers
Administration

Learning

PEOPLE

Volunteers
Community Leaders
NPO
Mass Media
Teachers and others.

Measures(Plan)
Improvement(Action)

Do

Check

Figure 1

Development of resident awarenessby experts and media cooperation

Figure 2

Procedure for disaster prevention
activities

2. OUTLINE OF WEBGIS SIMULATOR AND ITS APPLICATIONS
Figure 3 shows the procedures for improving community disaster mitigation activities by use of the proposeddisaster information and education system. The system is based around a simulator that provides realistic
appraisals of hazardous conditions in order to help each resident become aware of the hazards in his/her own
environment and learn both the necessity for, and the actual steps involved, in preparing for those hazards.
While the system can also be used as a tool to assist facilitators in carrying out disaster prevention activities, its
primary purpose is to encourage residents to carry out disaster prevention activities themselves by providingthem with the education materials that will help them regard earthquake dangers as familiar and solvableproblems.
A series of subsystems have been integrated using WebGIS to provide the following tools: a high-resolution
hazard map system capable of showing expected earthquake shaking intensity and liquefaction based on theactual geological conditions of an individual site; a three-dimensional birds-eye view system that shows thehistory of specific areas; a simulation system for earthquake ground motion utilizing high-resolution surface
soil models; a system for simulating the possible collapse of a wooden house after considering the site’spredicted earthquake ground motion (as well as a simulation system that shows the risks posed by fallingfurniture). To provide additional information on seismic hazards and disaster mitigation, various other online
e-learning tools based on WebLog, Wiki and other interactive interfaces have been developed and introduced.

th

The 14 World Conference on Earthquake Engineering
October 12-17, 2008, Beijing, China“I’m afraid of a big
earthquake. How
should I prepare forit ?”Choice of address

Animated menu window

Community information

Hazard map & aerial photo

Hazard map & topography

Aerial photos

3D cutting/filling
distribution

Animated menu for hazard maps
Ground motion simulator

House damage simulator

Furniture falling simulator

E-learning contents

Links to web-pages
for seismic retrofitting

Conversation interface

Knowledge baseusing Wiki interface“BURURU” :education materials

Town watching
Hazard mapping
Town map on WebGIS

Children’s disaster mitigation workshop

Figure 3

Outline of procedure for improvement of community disaster mitigation potentials and activities

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The 14 World Conference on Earthquake Engineering
October 12-17, 2008, Beijing, China

With these systems, residents can easily acquire knowledge on earthquake hazards, seismic activity evaluation
methods, and practical ways of retrofitting their houses and securing their furniture. Web-based technologies
make possible not only the integration of the subsystems, but also easy and interesting ways to utilize thesystem at any time.
The system is also designed to be available for user-groups that want to discuss and make preparations against
disasters using the WebGIS map system. This system is designed to make it possible for users to create,
maintain and use their own disaster response maps for disaster mitigation activities. The function is an effective
way to support residents who wish to lead community disaster mitigation activities.
3. WEBGIS-BASED SIMULATOR FOR PROMOTION OF SEISMIC RETROFITTING
3.1. WebGIS high-resolution hazard maps
Figure 4 shows examples of the WebGIS view windows. Figure 4 (a) is a start window. The two maps show
different (yet related) features for the same area and are connected in terms of movement andmagnification/reduction. Using them, it is possible to analyze various damage prediction results by comparing
aerial photos and topographical data. With this system, residents can also readily understand earthquake damage
predictions.
Community disaster prevention starts with learning about the community. Users can select the information
he/she wants to study from the menu on the left side of the window, while referring to the map. The map scaleand display area are selected by mouse operations. For example, if a resident clicks on the location where
he/she lives, the window shown in Figure 4 (b) displays the address and an information outline of the selectedarea with details such as: estimated seismic intensity, liquefaction risk, characteristics of the topography and theground, industrial, commercial, and residential characteristics, building characteristics, and the age distributionof residents.
Figure 4 (c) shows 40 years of change for an area using aerial photos while Figure 4 (a) shows a comparison of
the predicted seismic intensity and an aerial photo. Figure 4 (d) shows a comparison of the predictedliquefaction and a topographical classification map. The sample area is located on a hill where a valley and aridge meet. Examining these figures help residents comprehend the risk of seismic shaking and potential
liquefaction (which are strongly related to topographical features) and observe how things have changed overthe past decades.
Changes in the area’s topographical features are also shown in figure 4 (e) and 4 (f) using a three-dimensional
birds-eye view. The view is a composite of aerial photos that takes into consideration data on sea level states.
Observing changes to the sea level over the past 40 years, at each point, make it possible to show the
distribution clearing and filling (in the lower right of Figure 4 (f), the blue area shows clearing and the red areashows filling). This view is created by real-time three-dimensional programming, which is a common techniquein the field of dynamic and interactive web content development. As shown in Figure 4 (f), it is possible tochange the screen by moving the mouse and to make position changes (including moving, revolving, zooming
in and out on the screen and changing the point of view) by dragging the mouse. It is also possible to review
past history of the area by dragging the time bar. Because residents can easily visualize the changes in
topography around their houses, they can more fully understand the relation between seismic activity andtopography.
3.2. Simulator of seismic ground motion at a specific site
We developed algorithms for estimating the soil velocity structure shallower than the engineering bedrock andestimated seismic ground motions at the position of the engineering bedrock by the statistical Green’s function
method. We used this information to estimate the surface soil structure at a certain point and then constructed anearthquake response simulation system. As shown in Figure 5, if a point on the GIS is clicked, the system gives
soil model estimates for that point. After the soil response is calculated, the system displays an animation ofth

The 14 World Conference on Earthquake Engineering
October 12-17, 2008, Beijing, China

Connected WebGIS windows
二画面の連動するウェブGIS(b) Outline of selected area (in Japanese)(a) WebGIS window example(c) Aerial photos (left:1963, right:1998)(d) Potential liquefaction(left), topological classification (right)
1955

1939

1998

(e) Three-dimensional birds-eye view of WebGIS(f) Changes to topographic features over 40 years

Figure 4 High-resolution hazard map created via WebGIS and its effective application from a three-dimensional
birds-eye view

earthquake occurrence and the soil response for the site, as shown in the right side figure. This simulation
enables residents to see the vibrations applied to their houses and comprehend the relation between soil
hardness and its response. Photo 1 shows a specially-developed shaking table facility that allows a realistic
experience of simulated ground motions and building responses.

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The 14 World Conference on Earthquake Engineering
October 12-17, 2008, Beijing, China

Simulated ground

地震波形を表示response and input（地表と基盤のNS、EW）
waves

Animation of

地盤応答アニメーション
ground response
Fault process and earth-

震源過程と波動伝播の様子
quake wave propagation
Soil structure

Figure 5 Earthquake response simulator for the ground surface of a selected site

Photo 1 Shaking experience3.3. Simulator for earthquake damage to wooden houses and falling furnitureThis system was developed as a way for residents to check the seismic capacity of their own houses. There are
two input methods for two-story wooden houses. One, shown in Figure 6 (a), is a relatively simple method thatallows residents to input basic details on their houses, such as the year of construction, using web-based
choices. The other, shown in Figure 6 (b), is a more detailed input method and takes into consideration theactual plans of the house using an online Web-based CAD system. For both methods, as described in section
3.2., earthquake response analysis will be performed for the generated model subjected to the simulated
earthquake ground motion at the site. Figure 6 (c) shows the animated result of response analysis. Simulation
results that show house collapses will be referred to websites dedicated to seismic activity evaluation andretrofit in order to encourage the user to begin countermeasures. If the house does not collapse, the fallingfurniture simulator begins. The user will then be asked to input the floor on which the furniture is placed, theOuter wall

Plan
入力要素
Parts
list
補助パーツ

入力要素説明Instructions(a) Simple input method using webpage-based choices
Earthquake
wave
波動伝播と
propagation
緊急地震速報Outer
建 物 view
外 観

Furniture
家
具転倒
falling(b) Detailed input method using Web-based CADnd

2 floor2 階
furniturest

1 floor
1 階
furnitureview
建Inner物 内部(c) Animated response simulation results(d) Input window and the results of the furniture falling simulator
Figure 6 Simulation of house damage and falling furniture based on an individual’s house and furnitureth

The 14 World Conference on Earthquake Engineering
October 12-17, 2008, Beijing, China

size and weight of the furniture, the type of floor furnishings, etc. Once this is done, the furniture’s response isanalyzed based on the response waveform and displayed as an animation, as shown in Figure 6 (d), after which,the user is guided to websites promoting the safety of indoor environments.

4. LEARNING TOOLS WITH EFFECTIVE INTERFACES
The next step for residents who have become aware of their seismic risks and the importance of disastermitigation action is education. To facilitate this, we have developed and tested various learning tools andmaterials regarding ground vibration and building responses, seismic capacity and effectiveness of retrofit, andother related knowledge. These include a series of vibration experiment education materials collectively known
as “BURURU” (Fukuwa et al. 2008), which demonstrate fundamental and important points by use of simple
physical tools and online simulation software. One of the most popular examples of the BURURU series is apaper model two-story house kit and user manual that can easily be downloaded and printed. The paper model
can be used to explain the importance of roof weight, the effects of cross bracing, and the balance of walls.
Such hands-on educational materials are effective for supplementing virtual information systems. Other types of
e-learning assets have also been prepared concerning disasters and disaster mitigation. For example, in order toshow the effectiveness of furniture falling countermeasures, videos showing comparative experiments on
shaking tables (using by various prevention methods) can be viewed on the Internet. These tools make it easy toconfirm the effects of falling furniture prevention measures.
To assist in the development of such e-learning materials, we have utilized new technologies to create andnavigate between numerous online resources. One such is an application of the “Wiki” system, which we haveused as the foundation of a disaster mitigation knowledge database. Figure 7 shows an example. The Wikisystem is widely used on the Internet and has proved to be an effective method of building databases because it
operates by soliciting the collaboration and contributions of many users. Another example is an interactive
conversation interface designed to provide easy access to the web-based e-learning system. If a user verballyasks the system for answers to even vague questions, an appropriate reply will be generated using familiar
web-address navigation tools (Figure 8).

Teacher
教える役割

Questions
Input
box
質問入力欄

質問を
Guidance
誘導する役割Communication
ユーザを含めたlog

三者の会話ログ

Figure 7 Wiki for disaster mitigation knowledge base

Figure 8 Bururu interactive conversation interface

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The 14 World Conference on Earthquake Engineering
October 12-17, 2008, Beijing, China

5. SUPPORT SYSTEM FOR COMMUNITY DISASTER MITIGATION ACTIVITIESDeveloped systems have been tested during actual community disaster mitigation activities. One of the mostpopular uses of the system is the creation of hazard maps by residents that are based on their own knowledge
and information. Figure 9 shows an example of an online community hazard map created by the proposedsystem in conjunction with a newly developed input interface based on “WebLog.” WebLog is a popularinterface for making web-based diaries known as “blogs”, and can provide an effective foundation for thecontinuous activity needed to make and use such maps. Photo 2 shows active discussions during a workshop ofcommunity members. If facilitators or leaders can guide the group discussions, it is not necessary for eachparticipant to use the computer system individually.

Figure 9 Community disaster mitigation map systemproduced by WebGIS with WebLog interface

Photo 2 Community disaster mitigation workshop
using newly developed systems

6. CONCLUSION
In this paper, we discussed the development of a disaster information system built around a simulator thatprovides realistic seismic hazard scenarios in order to help each resident become aware of his/her own hazard
level and learn the need for, and methods of, home seismic retrofitting. It is clearly shown that WebGIS-based
systems are capable of providing a hazard map database in an easy-to-understand interface. Furthermore, it canbe easily seen that the simulator is effective in helping individuals evaluate their own environments as they
pertain to ground shaking, earthquake response, possible house collapse and indoor safety. The system has also
proved to be an effective part of community disaster mitigation activities.
In April this year, a fully-active version of this system was activated on the Internet website of Japan’s Aichi
Prefecture government, and a separate institution was also opened in Aichi prefecture to provide information on
disasters and disaster mitigation activities utilizing the proposed system along with various other kinds ofrealistic educational materials. Application of the system to various communities is ongoing and new
developments are expected for the future.
ACKNOWLEDGMENTS
The authors would like to express their thanks to: Member of the ATACK Conference, Prof. Y. Suzuki of
Nagoya University, Mr. K. Kurata and Mr. Y. Furuse of Falcon Corporation, Mr. T. Minagawa of Ebisu
Building Laboratory and Mr. I. Kawajiri of Nihon System Sekkei Co., Ltd. for their cooperation.
REFERENCES
Fukuwa, N., Hara, T., Hanai, T., Tobita, J. and Mori, M. (2008). Development of vibration experimenteducation materials for structural and soil dynamics. Proc. 14WCEE.