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1. Title

Seismic Retrofitting for School Buildings in Japan- Publication of a Reference Book -

ID: DRH 41 Installing Steel Bracing
Hazard: Earthquake
Category:

Implementation Oriented Technology (IOT)

Proposer: Takayuki Nakamura
Country: JAPAN;
Date posted: 24 September 2008
Date published: 07 November 2008
Copyright © 2008 Takayuki Nakamura (proposer). All rights reserved.

Installing Steel Bracing

Contact

(1) Masao YAMAKAWA (MEXT)
Director, Office for Disaster Prevention, Ministry of Education, Culture, Sports, Science and Technology (MEXT)
m-yama@mext.go.jp, TEL: -81-3-6734-2290

(2) Koichi SHINPO (NIER)
Director, Educational Facilities Research Center, National Institute for Educational Policy Research (NIER)
shinpo@nier.go.jp, TEL: -81-3-6733-6990

(3) Takayuki NAKAMURA (Hokkaido University)
Director, Facilities Department, Hokkaido University
s-bucho@facility.hokudai.ac.jp, TEL: -81-11-706-2063

2. Major significance / Summary

Earthquakes can occur anywhere and at any time in Japan. Improving the seismic resistance of school buildings is a pressing issue, because children spend a large part of their daily lives in school. MEXT published a reference book for retrofitting school buildings under the cooperation with NIER. The book includes many seismic retrofitting examples with various pictures, charts and plans. Even though the readers don’t have enough technical knowledge and information about seismic retrofitting, they can easily understand what are critical for retrofitting existing school buildings.
Readers are encouraged to access the full text of the Reference Book at (http://www.nier.go.jp/shisetsu/pdf/etaishinjirei.pdf )
MEXT: Ministry of Education, Culture, Sports, Science and Technology
NIER : National Institute for Educational Policy Research

3. Keywords

Seismic retrofitting, School buildings


II. Categories

4. Focus of this information

Implementation Oriented Technology (IOT)

5. Users

5-1. Anticipated users: Administrative officers , Municipalities , National governments and other intermediate government bodies (state, prefecture, district, etc.)

5-2. Other users: Policy makers

6. Hazards focused

Earthquake

7. Elements at risk

Human lives , Buildings


III. Contact Information

8. Proposer(s) information (Writer of this template)

(1) Masao YAMAKAWA (MEXT)
Director, Office for Disaster Prevention, Ministry of Education, Culture, Sports, Science and Technology (MEXT)
m-yama@mext.go.jp, TEL: -81-3-6734-2290

(2) Koichi SHINPO (NIER)
Director, Educational Facilities Research Center, National Institute for Educational Policy Research (NIER)
shinpo@nier.go.jp, TEL: -81-3-6733-6990

(3) Takayuki NAKAMURA (Hokkaido University)
Director, Facilities Department, Hokkaido University
s-bucho@facility.hokudai.ac.jp, TEL: -81-11-706-2063

9. Country(ies)/region(s) where the technology/knowledge/practice originated

JAPAN;

10. Names and institutions of technology/knowledge developers

Ministry of Education, Culture, Sports, Science and Technology (MEXT), National Institute for Educational Policy Research (NIER)

11. Title of relevant projects if any

12. References and publications

13. Note on ownership if any


IV. Background

14. Disaster events and/or societal circumstances, which became the driving force either for developing the technology/knowledge or enhancing its practice

In recent years, there have been frequent large earthquakes in Japan, such as the 2004 Mid-Niigata Prefecture Earthquake and the 2005 Fukuoka Seihou-oki Earthquake.  It is hard to tell when and where such earthquakes could occur in Japan.     Improving the seismic resistance of school buildings has become a pressing issue, because children spend a large part of their daily lives in school, and such schools secure the safety of children as well as act as emergency evacuation facilities for local communities. Therefore, the Ministry of Education, Culture, Sports, Science and Technology (MEXT) has taken measures for early application of seismic retrofitting on school buildings.  This was by producing the "Guideline for Promoting the Seismic Retrofitting of School Facilities" to tackle the retrofitting of school buildings.   Furthermore, there is great demand for the effective, efficient and systematic improvement of school buildings under the tight fiscal situation of the government and regional authorities.  There is a need to study methods for more effective improvements, such as by shifting from the replacement of buildings to the seismic retrofitting and refurbishment of buildings in the future.  However, the general public and those in charge of school buildings are usually not acquainted with seismic retrofitting, and there were opinions that it is difficult to imagine what retrofitting is about and how much it would cost. 

Therefore, MEXT commissioned the Research Institute of Educational Facilities in 2005, and performed the "Investigative research on seismic retrofitting of school facilities". Then, MEXT published a reference book on school buildings to resist earthquakes, based on the survey on examples of seismic retrofitting methods throughout Japan. This reference book is intended to make it easier to understand for those who are not specialized in architecture, and to contribute in improving the understanding of the importance of seismic retrofitting as well as for further applications of seismic retrofitting.

 

 

                         

   

            Collapsed  Column                                       Fallen  Roof

 

 

 

               

 

 

                     

 

                       

               Steel  Bracings                                                                       Steel  Bracings (Details)


V. Description

15. Feature and attribute

After introducing some examples of school buildings damaged by recent major earthquakes and explaining about the background information of seismic retrofitting, this reference book shows the following examples of retrofitted school-buildings. - Retrofitting structures with steel bracings and seismic shear walls    - Retrofitting by installing steel bracings and structural slits    - Retrofitting of structures with steel tube bracings    - Retrofitting the structure by replacing the roof    - Retrofitting of structure with steel tube bracings and seismic shear walls- Retrofitting the structure by installing external steel bracings and seismic shear walls    - Retrofitting structures by installing steel frame bracings and bracings along the roof    - Retrofitting structures by installing external horizontal steel truss Each example above-mentioned describes the outline of seismic retrofitting method, the approximate cost, the effectiveness of retrofitting, the design for retrofitting, the explanation of keyword for retrofitting, etc. In addition to these examples, the reference book includes simple description of other 14 seismic retrofitting cases. 

16. Necessary process to implement

Arousing Awareness

In Japan, municipal governments are responsible for public school buildings. Though the national government funds approximately two-thirds of the cost for retrofitting school buildings through grants, the one-third of the costs must be budgeted by local municipalities.  Therefore, it is necessary to arouse awareness of the importance of seismic resistance in school buildings in order to promote them.   For this purpose, the results of the yearly survey done by MEXT concerning the seismic resistance capacity evaluation rates and seismic resistance rates of public schools of each municipality is disclosed.  Also, MEXT urges local authorities to disclose the seismic resistance capacity evaluation results and plans for retrofitting of each school. 

Sufficient and Adequate Information    

MEXT cooperating with architectural experts, conducted research and study of earthquake resistance for school buildings to establish seismic resistance capacity evaluation methods for school buildings, present methods for seismic retrofitting, and also compile examples of seismic retrofitted school buildings that municipalities can use as reference. Also, MEXT established a consultation service where municipalities and school building designers can seek technical advice. 

Budgetary Measures  

Because retrofitting school buildings is costly, budgetary measures is essential for progress.  Not only securing enough budgets for subsidies, but other measures such as reforming the subsidy system for a more flexible use by the local municipality, have also been taken.

17. Strength and limitations

Strength

The purpose of this reference book is to enlighten the general public and those who are in charge of school buildings with understandable manners. There are many pictures, charts and plans in this reference book, so the readers can easily understand what are necessary for retrofitting existing school buildings. 

Limitations

In order to apply the technologies shown in this reference book to other real cases, more detailed investigations and analyses about the real case are necessary. Especially, when these technologies are applied to the cases in foreign countries, more careful attention to the regional characteristics and social backgrounds ought to be paid.

18. Lessons learned through implementation if any

It is costly to retrofit vulnerable school buildings, and municipalities have to address other public needs; therefore there is a difficult condition to assign higher budgets to school buildings. Under these budget constraints, it is critical to develop cheaper technologies for retrofitting existing school buildings.


VI. Resources required

19. Facilities and equipments required

20. Costs, organization, manpower, etc.


VII. Message from the proposer if any

21. Message

It is clear that school buildings should be built to withstand earthquakes. In addition, since school buildings are places where many children spend the most part of the day to study and live, it is also crucial to maintain school buildings safer and more healthy conditions. Therefore, the improvement of educational circumstances ought to be paid attention at the time of retrofitting school buildings.


VIII. Self evaluation in relation to applicability

22. How do you evaluate the technology/knowledge that you have proposed?

It is a technology/knowledge that has high application potential verified by implementation in various field sites.

23. Notes on the applicability if any

The technologies introduced in this reference book are thought to be applicable to other regions in the world. However, in that case, more careful attention to the regional characteristics such as building materials, structural components, skills of construction workers, etc. should be paid.


IX. Application examples

No.1

    E1-1. Project name if available

    Retrofitting Structures with Steel Bracings and Seismic Shear Walls


    E1-2. Place

    Niigata Prefecture, Toukamachi Sougou Senior High School 


    E1-3. Year

    2004-2005


    E1-4. Investor

    Niigata Prefecture


    E1-5. People involved


    E1-6. Monetary costs incurred

    Total Cost: 173.5 million yenCost for retrofitting: Steel bracings: 254,000 yen/ m2, RC Wall: 140,000 yen/m2


    E1-7. Total workload required


    E1-8. Evidence of positive result

    Is value (Structural seismic performance index):  Before: Isx=0.30, Isy=0.69

      After   : Isx=1.01, Isy=0.88

     

     

                   

     

                       

     

               After retrofitting (Inside view)                                Before retrofitting (Outside view)  


No.2

    E2-1. Project name if available

    Retrofitting by Installing Steel Bracings and Structural Slits


    E2-2. Place

    Niigata Prefecture, Toukamachi Senior High School


    E2-3. Year

    2003-2005 (3months/each year)


    E2-4. Investor

    Niigata Prefecture


    E2-5. People involved


    E2-6. Monetary costs incurred

    Total cost: 343.8 million yenCost for retrofitting:    Install steel bracings: 125,000yen/m2, Install RC wall: 88,000yen/m2, Steel jacket reinforcement of columns: 254,000yen/each, Carbon fiber jacket reinforcement of columns: 385,000yen/each


    E2-7. Total workload required


    E2-8. Evidence of positive result

    Is value (Structural seismic performance index):  Before: Isx=0.42, Isy=0.39

      After   : Isx=0.80, Isy=0.75

     

     

     

     

          

                          Installing Steel Bracing                                           Adding Seismic Shear Wall      

     

     

     

     

                       

                    Carbon Fiber Reinforcement                                 Steel Jacket Reinforcement

     

      


No.3

    E3-1. Project name if available

    Retrofitting of Structures with Steel Tube Bracings


    E3-2. Place

    Niigata Prefecture, Kawaguchi Junior- High School Gym


    E3-3. Year

    1997


    E3-4. Investor

    Kawaguchi Town


    E3-5. People involved


    E3-6. Monetary costs incurred

    Total Cost: 101.7 million yenCost for retrofitting:     Steel bracings: 10,000yen/m2


    E3-7. Total workload required


    E3-8. Evidence of positive result

    Is value (Structural seismic performance index):

      Before: Isx=0.08, Isy=0.70

      After   : Isx=0.73, Isy=0.70

     

     

     

     

     

      

                                                  

                              Steel  Tube  Bracings

     

     



X. Other related parallel initiatives if any

Message

Other 19 examples of retrofitting school buildings can be seen at the following website. (http://www.nier.go.jp/shisetsu/pdf/e-taishinjirei.pdf )


XI. Remarks for version upgrade

Message

Attached files:

Similar technologies

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