Courtesy: Living with Risk, 2004, UN ISDR Secretariat

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1 Experiences of Japan for Safer Building Kenji Okazaki Professor National Graduate Institute for Policy Studies (GRIPS)

2 Scariest things in life in Japan (until WW II) 1. Earthquake 3. Fire 2. Lightning/ thunder 4. Father

3 Edo citizens beating the legendary Catfish which was believed to have caused 1855 earthquakes

4 Japan is prone to natural disasters A show case of disasters Heavy rain in summer, causing floods, land slides, and mud flow Several typhoons in autumn Heavy snow in winter - accumulation would reach 4-5 ms high h Volcanic eruptions Strong earthquakes and tsunamis - 10% of whole earthquake energy in the world is released around Japan.

5 Courtesy: Living with Risk, 2004, UN ISDR Secretariat

6 Casualties due to Natural Disasters in Japan Mikawa Earthquake Makurazaki Typhoon Fukui Earthqu ake 5868 The Great Hanshin-Awaji Earthquake Torr enti al Rain Toyamaru Typhoon Isewan Typhoon

7 Earthquakes hit Japan frequently The 1891 Nohbi Earthquake (M 7.9) ) The 1923 Kanto Earthquake

8 1896 Meiji Sanriku Earthquake Tsunami

9 History of major earthquake disasters Earthquakes with more than 1,000 deaths in the past 100 years Earthquake year Magnitude Deaths Kanto Kita-tango ,000 2,900 Sanriku ,000 Tottori ,100 Mikawa ,000 Nankai ,300 Fukui ,900 Hanshin-Awaji ,400

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11 Seismic Hazard Map A Seismic Hazard Map shows the predicted likelihood of a strong ground motion occurring in a given area within a set period of time. Probabilities of intensity 6 and over Within 30 years The intensities with 3 % probability within 30 years

12 Estimated earthquake intensity of Tokai Earthquake 1707: Hoei Earthquake 1854: Ansei Earthquake

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14 Estimation of intensity of Tokyo Inland EQ Estimation of damage to houses and buildings in Central Tokyo

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16 The Japan Meteorological Agency (JMA) Earthquake Monitoring Earthquake Prediction Issuance of Information Seismic Intensity Map Date: Aug. 18, 2000 Time: a.m. (JST) M: 3.6 Depth: 36km Station Distribution in Japan

17 Earthquake observation by NIED National Research Institute for Earth Science and Disaster Mitigation K-Net A system which sends strong-motion data on the Internet, data obtained from 1,000 observatories Hi-Net High sensitivity i i Seismograph network

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19 Real-time Earthquake Warning It estimates arrival times of principal seismic waves, seismic intensities before the seismic wave reaches. The information is issued from few seconds after the occurrence of an earthquake based on the limited number of data from the source region of the earthquake. This information is expected not only to quicken the issuance of tsunami forecast but to give time to stop plant operation, elevators, railways etc. to reduce damage.

20 Great Hanshin-Awaji Earthquake AM 5:46 17 Jan Magnitude 7.3 Intensity 7 (JMA scale)

21 Death: 6,434 people Injured: j 43,792 people p Buildings damaged: 640,000 buildings (severely damaged: 250,000 buildings for 460,000households Buildings burnt by fire: 7,500 buildings for 9,000 households in 70 ha Evacuees: 319,000 people at peak Number of evacuation areas at peak: 1, Financial damage:jpy 9.9 trillion ($ 87 billion, 2.5% of GDP) Building damage: JPY 5.8 trillion (60% of damage)

22 Lessons from 1995 Kobe (Great Awaji) Earthquake Hanshin-Awaji) Ear Focusing on Building and Housing Damage beyond imagination The more a city develops, more complicated a disaster becomes.

23 Vulnerable houses magnified the disaster Most of immediate deaths were caused by the vulnerable conventional (wooden) houses Cause of Death (1) Collapse of Buildings No. of death 4,831 88% (2) Fire % (3) Others (Slide, Transportation) 121 2% Total 5, %

24 Most of indirect deaths were also caused by the vulnerable houses - Approx. 900 people died within several years after the earthquake. - They died because of the bad conditions of refugee life (overcrowded, prolonged, no privacy, loneliness, li etc.) Collapsed houses blocked roads, and hampered evacuation, relief, and fire fighting activities

25 Old wooden houses were severely damaged 100% Minor damage and no damage 80% 60 60% 40% medium damage % % 0% Larger damage Acceleration(gal) Before 1971 Before 1981 After 1981

26 Expenditure of the government directly attributed t to housing collapse is huge Total: more than $15 billion (the national government) = $150,000 / destroyed house (almost equal to construction cost) 2.9 $ 1 = 100 yen (1995) Housing Temporary Debris Aid Others

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28 Uncontrolled fires (Approx. 7,000 buildings and 70 hectares were burnt out) - Number of fires overwhelmed the fire fighting ability - Available water was not sufficient -Fire fighters arrived late on the sites - Fire fighting operation was not sufficient (where to go?)

29 Disposal of debris

30 Impact to environment Disposal of debris/waste (20 million tons from 20 municipalities 8 times of usual year) Chemical subsistence burnt during fires Scattering asbestos used in the demolished buildings Dioxin emitted from incineration

31 Evacuation and Temporary housing ,000 people evacuated in 1,153 places. - Many people lived at schools for long period. Living i conditions i were poor and harsh. h - Smaller facilities are more serviceable and comfortable for people to live in for long term. Local communities were destroyed by geographic mismatch of temporary housing - Difficulties to find location for temporary housing - Priorities were given to the weak who were moved to remote areas

32 Temporary housing

33 Evacuation and Temporary housing ,300 temporary houses were constructed within 7 months. - Delay was caused as their construction is approved only on public lands and it took time to secure the construction sites. - Poor livability - People did not know each other.

34 Reconstruction ti of housing Public housing-orientedoriented - Publicly operated 71,600 units were constructed, still short for the needs. - Geographical mismatch of housing provision. - Double housing loans Loss of community - Number of suicides remains high Reconstruction rather than repair

35 Towards safer housing Many old vernacular wooden houses collapsed. - 80%of victims were killed by their own houses. - Appropriate structural planning, diagonal bracing, and horizontal rigidity are essential. Buildings should not collapse or burn Repair rather than demolition and rebuilding - Repair cost is 15% or less of reconstruction. Public support is necessary for retrofitting of existing vulnerable houses

36 Lessons from earthquake disasters in the world Earthquakes do not kill people, buildings do. To reduce damage caused by earthquakes, particularly casualty, existing vulnerable houses must to be reinforced/retrofitted. Newly built houses must meet building codes/guidelines.

37 Vulnerable houses

38 Kathmandu Valley: Urban Area

39 Enforcement of Building Codes (BSL) It is supposed that all the buildings newly constructed comply py with BSL in Japan However, it turned out that many existing houses did not meet the current technical requirements. It is the biggest issue how we can convince people that investment in retrofitting would be worthwhile.

40 Conventional houses in Japan Historically, wooden houses (post-and-beam) are dominant. S/RC 33% Wooden 64% Wooden S/RC Others Others 57% Wooden 43% Wooden Others Total number (existing): approx. 47 million units (2003) Annual construction: approx. 1.3 million units (2005)

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42 Effect of retrofitting before retrofitting after retrofitting

43 Simplified Seismic Diagnosis for wooden houses

44 To better understanding gy your own risk Simplified seismic diagnosis

45 E-Defense, NIED A full size three-dimensional vibration destruction facility since 2005

46 Shake Table Testing (full scale at E-Defense)

47 Development of technologies for retrofitting Examples of methods for seismic reinforcement of wooden houses puncheon strapping plywood Examples of seismic reinforcement of apartment houses Installation of earthquakeresisting walls and braces Reinforcement of joints Damper hardware for seismic control Example 1 of reinforcement of pilings Example 2 of reinforcement of pilings

48 External Energy Dissipation Braces

49 Tokyo Densely inhabited areas of Tokyo and Osaka Densely urbanized areas (about 6,000ha) Center frame axes running through densely urbanized areas 東京都豊島区 de se y u ba ed a eas Toshima Ward, Tokyo Osaka Densely urbanized areas (about 6,000ha) 大阪府寝屋川市 Neyagaya-shi, Osaka

50 Measures for promoting Fireproof Buildings and the Urban Structure Before Fire-proof Improvement After Fire-proof Improvement