Building Damage by the 2011 Off the Pacific Coast of Tohoku Earthquake and Coping Activities by NILIM and BRI Collaborated with the Administration
1
Building damage by the 2011 off the Pacific coast of Tohoku earthquake and coping activities by NILIM and BRI collaborated with the administration
Isao Nishiyama (NILIM), Hiroshi Fukuyama ((),BRI), Yasuo Okuda (BRI), and Izuru Okawa (BRI).
NILIM : National Institute for Land & Infrastructure Management BRI :Building Research Institute
This material was presented at UJNR ‐ Wind and Seismic Effects held at PWRI on August 29, 2011. 2
1. Outline By Nishiyama, Isao 3
Field Survey
Quick Report (in Japanese) was published on May, 2011 and Summary Report (in English) will soon be available.
Isao Nishiyama 4 JMA SiSeismi c IItntens ity & HtlHypocentral RiRegion
Tooouhoku eart hqua ke Mw=9.0 (14:46 JST on March 11, 2011) ★
Isao Nishiyama 5 Fie ld SdSurveyed Cities and Towns
Tono City Miyako City
Yamada Town Kitakami City Otsuchi Town Hiraizumi Town Kamaishi City
Ohunato City Kurihara City Rikuzentakata City Kesennuma City Tsunami‐inddduced Minamisanriku Town
Ishinomaki City damage Onagawa Town Higashimatsushima City Matsushima Town Shiogama City Shichigahama Town Tagajo City Sendai City Motion‐induced Natori City Iwanuma City damage Watari Town Yamamoto Town Shiroishi Town Nasu Town Fukushima City Fukushima Daiichi Nuclear Nihonmatsu City Yaita City Miharu Town Power Station Koriyama City Shirosato Town Sukagawa City Kasama City Shirakawa City Hitachiota City Chikusei City Hitachi City Shimotsuma City Naka City Hitachinaka City Mito City Koga City Liquefaction‐induced Oarai Town Bando City Omitama City Joso City damage of houses Hokota City Tsuchiura City Kashima City Ryugasaki City Itako City Surveyed Cities and Kamisu City Towns Sakae Town Inashiki City Urayasu City Isao Nishiyama 6 SdSurveyed Items
∗ Motion‐induced damage ∗ Wood houses, steel buildingg,s, reinforced concrete buildings, residential land, non‐structural elements, seismically isolated buildings,…etc. ∗ Tsunami‐induced damage ∗ Wood houses, steel buildings, reinforced concrete buildings. ∗ (Fire‐induced damage...)
Isao Nishiyama 7 Damage Sta tisti cs (To hok u vs. KKb)obe)
60,000 People injured People Death People missing 50,000 People death Tohoku: 15,700 40,000 Kobe: 6,434
30,000
20,000
10,000
0 3/12 3/19 3/26 4/2 4/9 4/16 4/23 4/30 5/7 5/14 5/21 5/28 6/4 6/11 6/18 6/25 7/2 7/9 7/16 7/23 Kobe EQ 500,000
450,000 Half collapsed (house) 400,000 Total collapsed include washed away (house) 350,000
300,000
250,000
200,000 Total Collapsed Buildings 150,000 Tohoku: 114,000 houses 100,000 Kobe: 186,175 housing units 50,000 0 3/12 3/19 3/26 4/2 4/9 4/16 4/23 4/30 5/7 5/14 5/21 5/28 6/4 6/11 6/18 6/25 7/2 7/9 7/16 7/23 Kobe EQ (housing Isao Nishiyama units) 8
Coping Activities
Isao Nishiyama 9 Four IttImportant Issues
∗ Tsunami Damage ∗ Non‐structural Elements Damage, esp. Ceiling ∗ Long‐period, Long‐duration Ground Motion Effects ∗ Liquefaction Damage ∗ (Damper Damage in Seismically Isolated Building)
Isao Nishiyama 10 TiTsunami
Out of plain deformation, RC
AhArahama, WkbWakabayas hi, Sen da i IidInside, ditto ∗ Study on the design of tsunami evacuation buildings, i.e. estimation of tsunami load More than half of the total inundation area was subjected to inundation height of 2m or less.
Isao Nishiyama 11 Non‐sttltructural Element s, esp. CiliCeiling
Structures
Structures
Ceiling Braces Clearance
Clearance between ceilings Earthquake induced motion Ceiling is contacting to Structural Members
Stiffness difference between Earthquake induced ceilings in different levels motion
Previous technical advice (MLIT, 2003.10) ∗ Review of previous technical advice (right), and study on practical structural calculation methods
Isao Nishiyama 12 Long‐pp,eriod, Long‐duration Ground Motion
Pseudo Vel. Resp. Spectrum (h=5%) Disp. Response Spectrum (h=5%) 50 60 00 1 100001F(NS) 01F(NS) 01F(EW) 01F(EW) 01F(UD) 01F(UD)
0 )
m/s) 1 mm cc 10 40 10
5 elocity Response ( cement Response (c VV aa 20 Displ /s/s) Pseudo 1 1(cm 0. 1 1(cm) 0.5 0 0.1 0.5 1 5 10 0510 Period (sec) Period (sec) Pseudo‐velocity Displacement Osaka prefectural government building (Sakishima) ∗ Tentative new proposal by MLIT and NILIM was announced for public comments Dec. 21, 2010. 3 months before Tohoku EQ. ∗ Background information was published in BRI.
Isao Nishiyama 13 Liquef acti on
Nisshiro, Inashiki, Ibaraki
Fukashiba, Kamisu, Ibaraki ∗ Study on possible indication of expected performance w/wo countermeasures for residential houses (from the view of consumer prottitection)
Isao Nishiyama 14 (Damper in SiSeism icall y IltdIsolated Bldg. )
∗ LRB (Lead rubber bearing) ?
Fracture of Lead damper Isao Nishiyama 15 CtCountermeasures in CdCodes /Std/Standar ds
Building Structural Codes/Standards Committee Draft of Chaired by Tetsuo Kubo, Tokyo University Building Field Survey on the Earthquake on April 21 and 22 Structural First meeting was on June 8, second on August 18 Codes Public comments on Tentativ e WG on Long‐period New Proposal of earthquake ground motion countermeasures for long‐period First meeting was on July 20 motion Collection of information by Secretariat for supportin g using grant‐in‐aid for Committee and WG maintenance and promotion TG on Building Structural Codes of building standards Public and Standards in general 42.Effect of long‐period comments or First meeting on July 26 motion on super high‐rise proposal of buildings building structural 21. Needs and seeds codes from collection private Isao Nishiyama 16
2. Building Damage due to Earthquake Ground Motions By Fukuyama, Hiroshi Damage to buildings caused by seismic motion 17
• Wood Structure：Typical seismic damage was observed • RC Structure, Steel Structure：Significant difference appears between before and after the new seismic design code (1981). Typical seismic damage was observed • NonNon--structuralstructural Elements：Fall of suspended ceilings in largelarge--scalescale spaces, exterior walls, and interior materials were observed • Residential Land：Damage to developed grounds and sloping for residential houses were observed. Severe liquefaction damage occurred in very wide areas.
Hiroshi Fukuyama In Kurihara City, City, JMA seismic intensity of VII was recorded, 18 predominant spectrum is observed in short period, i. e. less than 0. 3s. But the power of spectrum in long period is lower than the limit value regulated in Building Standard Law of Japan for seismic design. Building damage was not so significant on the whole even in the areas where seismic intensity of more than VI was recorded 500 築館 KuriharaMYG004 (IJMA=VII) h=0.05 400 仙台 + Building SendaiMYG013 (IJMA=VI ) Standard law of 300 Shiogama塩竈MYG012 (I =VI+) JMA Japan (cm/s) vv 200 (So il type III) pS (Soil type II) 100
0 000.0 050.5 101.0 151.5 202.0 252.5 Pid()Perio303d(.0s ) PseudoPseudo--velocityvelocity response spectrum at some KK--NETNET observe points Hiroshi Fukuyama Typical seismic damage to Wood Structures 19
Damage of houses with store Damage due to (Inclination of 1st story) Bio‐deterioration
Damage of Dozo (Japanese traditional wood Collapse of 1st story Collapse of19 2nd story storehouse coated with clay and plaster finish) Hiroshi Fukuyama Typical seismic damage to RC Structures 20
Collapse of soft‐1st story Shear failure of by shear failure of columns non‐structural walls
Pullout of anchor bolts of the exposed‐type SRC Shear filfailure of Shear filfailure due to column base link‐beam20 opening of shear wall Hiroshi Fukuyama 21 Typical seismic damage ––RCRC structure (1)
• More than 10 local government office buildings designed by the old seismic code suffered from significant structural damage, shear failure of short columns and loss of axial load bearing capacity . These building could not be used as an emergency operation center.
• Damage mitigation for functional continuity is strongly required.
Kasama City hall building Sukagawa City hall building Hiroshi Fukuyama 22 Typical seismic damage ––RCRC structure (2)
• Most of the retrofitted buildings performed well to secure human lives by preventing collapse.
• Damage were observed in some retrofitted buildings
Hiroshi Fukuyama 23 Typical seismic damage ––RCRC structure (3)
Damage to non‐structural walls of residential buildings retrofitted by oil damper
Courtesy of Mr. K. Watanabe of U.R.
23 Hiroshi Fukuyama Typical seismic damage to Steel Structures 24
Buckling of brace Rupture of horizontal brace Spalling of concrete at joint
コンクリート剥落
Rupture of Buckling of diagonal Dropping of extensive ceiling brace at joint member of latticed materials and exterior finish column 24 materials Hiroshi Fukuyama Typical seismic damage to Residential Land25
Tilted 3 degrees
Large‐scale liquefaction and settled or tilted structures Sand boiling and tilting of house
FilFailure of htighooting caused LdLand slidin g on the slope Damage of by the ground damage of the developing25 hill retaining wall and house movement Hiroshi Fukuyama Typical damage to Non-Non-structuralstructural Elements26
Cracking and Failure of glass Fall of exterior wall panels spalling of tile
Damage and fall of suspended26 ceiling Hiroshi Fukuyama Typical damage to Seismically Isolated Buildings27
Damage to cover‐panels Damage to Peeled off of paint on for fire protection expansion joint U‐shape dampers
Lead damper and crack27 on the surface Hiroshi Fukuyama 28 CtCountermeasures
Most of the damage classified were observed in the previous earthquakes. Then previous revising of codes (or handbook) are effective for preventing the damage.
However, fall of suspended ceilings in largelarge--scalescale spaces, liquefaction damage, and damper damage in seismically isolated building are forced to take prompt measures.
Detailed investigation on damage to retrofitted buildings and government office buildings are now onon--going.going.
Hiroshi Fukuyama 29
3. Damage to Buildings in IdtiInundation Areas due to Tsunami By Okuda, Yasuo Purpose of Investigation 30
The purpose of this investigation is 1) To understand an overview of buildings damaged by tsunami, 2) To obtain basic data and information required to evaluate mechanisms for causing damage to the buildings 3) To contribute to tsunami load and tsunami‐resistant designs for buildings such as tsunami evacuation buildings
by means of 1) collecting building damage cases by tsunami 2) classifying the damage patterns for different structural categories, 3) making a comparison between the calculated tsunami force acting on buildings and the strength of the buildings
Yasuo Okuda Investigation Team for Tsunami 31 Damage
NILIM: 8 members BRI: 19 members Isao Nishiyama Juntaro Tsuru Nobuo Furukawa Akiyoshi Mukai Masanori Iiba Shoichi Ando Ichiro Minato Wataru Gojo Hiroshi Fukuyama Atsuo Fukai Yasuo Oku da TikiTaiki SitSaito Bun‐ichiro Shibazaki Koichi Morita Shuichi Takeya Hiroto Kato Tsutomu Hirade Hitomitsu Kikitsu Takashi Hasegawa Tadashi Ishihara Hiroshi Arai Norimitsu Ishii Yushiro Fujii Tomohiko Sakata Haruhiko Suwada Yasuhiro Araki Toshikazu Kabeyasawa
Yasuo Okuda Human Damage House Damage
Complete Below Prefecture City, Town, Village Partial Dead Missing Injury Destruction Partial Fire Damage or Missing Damage 32 Hachinohe 1 1 17 250 769 2 Summary of Damage Aomori Hashikami 0 0 0 12 8 1 Total 1 1 17 262 777 1 2 Hirono 0 0 0 10 16 5 Kuji 2 2 8 65 210 in Inundation Area Noda 38 17 309 169 1 Hudai 0 1 1 Tanohata 14 19 8 225 45 4 Iwate Miyako 420 124 33 3,669 1,006 176 6 Yamada 597 256 Unknown 2,7893,677 395 120 2 Due to Tsunami Otsuchi 796 653 Unknown 2 Kamaishi 881 299 Unknown 3,188 535 120 3,629 Ofunato 331 118 Unknown Unknown 2 Rikuzentakata 1,546 569 Unknown 3,159 182 27 Total 4,625 2,041 67 20,720 2,558 452 13 1. about 106,000 houses were Kesen-numa 1,004 410 Unknown 8,533 2,313 3,248 8 Minamisanriku 550 437 Unknown 3,167 144 Unknown 5 gawa 535 414 2 2,939 337 640 5 Ona completely destructed or Isinomaki 3,153 890 Unknown 19,065 3,354 10,199 23 Higashimatsushima 1,044 104 Unknown 4,589 4,672 2,471 1 Matsushima 2 0 37 213 1,321 1,184 2 Rifu 1 1 1 59 508 1,732 missing mainly in Iwate, Miyagi Shiogama 20 1 10 682 2,784 3,973 8 Shichigahama 66 6 Unknown 729 460 1,067 Tagajo 188 3 Unknown 1,662 2,993 5,097 15 Miyygagi and Fukushima Sendai 704 33 2,276 19,922 41,344 56,347 39 Natori 911 82 Unknown 2,786 922 8,060 12 Iwanuma 183 1 293 720 1,545 2,403 1 prefectures Watari 256 5 44 2,459 1,032 1,985 3 Yamamoto 670 23 90 2,200 1,042 1,086 2 Total 9,287 2,410 2,753 69,725 64,771 99,492 124 Shinchi 107 3 3 548 Unknown 2. about 100,000 houses were Soma 454 5 71 1,049 643 3,092 Minamisoma 633 38 59 4, 682 975 Namie 141 43 Fukushima Futaba 29 6 1 58 5 partially damaged Okuma 73 1 30 Tomioka 19 6 Naraha 11 2 5 50 3. about 106,000 houses were Hirono 2 1 Unknouwn Unknown Iwaki 308 39 4 6,585 18,931 21,800 3 Total 1, 777 144 143 13, 002 20, 554 24, 892 3 Kitaibaraki 5 1 188 339 1,569 5,745 3 below partially damaged Takahagi 1 19 131 728 3,213 Hitachi 166 403 3,016 11,229 4 Tokai 4 5 56 104 3,150 2 Ibaraki Hitachinaka 2 27 79 720 5,863 1 Oarai 1 6 10 268 1,087 Hokota 15 96 524 4,863 3 Kajima 1 368 1, 726 2, 567 4 Total: about 370,000 Kamisu 6 139 1,660 3,011 3 Total 14 1 432 1,621 10,315 40,728 20 Choshi 19 23 105 1,938 Chiba Asahi 13 2 12 336 931 2,358 Total 13 2 31 359 1,036 4,296 0 Yasuo Okuda Sum Total 15,717 4,599 3,443 105,689 100,011 169,861 162 33 Classification of Damage Patterns Reinforced Concrete Buildings (1) Collapse of first floor
A case where column capitals and bases on the first floor in a building were subject to flexural failure and subsequently to story collapse was seen in two‐story Yasuo Okuda buildings. 34 (2) Overturning
Overturning was observed in 4‐story or lower buildings. In all overturned buildings, the maximum inundation depth exceeded their height. Overturning types include building that felt sidelong and buildings that turned upside down.
Yasuo Okuda 35 (3) Movement and washed away
Most of the overturned bbildiuildings were moved from thiheir original positions. It is estimated that large buoyancy acted on the buildings. Moved and overturned buildings left no dragged traces on the ground.
Yasuo Okuda 36 (4) Tilting by scouring
When tsunami acted on a building, a strong stream was generated around the corner of the building, resulting in many large holes on the ground that were bored by scouring. In one case, a building on mat foundation fell into a hole bored by scouring.
Yasuo Okuda 37 (5) Fracture of wall
In one damaged building, a 300 mm‐thick shear wall with double layer bar arrangement and a support span of more than 10 m and without no 2‐story floor was bent inside by a tsunami wave pressure.
Yasuo Okuda 38 (6) Debris impact
Debris impact was seen in most of the non‐structural members such as window and ceiling materials. The number of cases of clear damage to skeletons was not large, but in one observed case, a multi‐story wall in an apartttment house was probbblably bored by debris impact . Yasuo Okuda Classification of Damage Patterns Steel buildings 39 (1,2) Movement and washed away
Debris impact was seen in most of the non‐structural members such as window and ceiling materials. The number of cases of clear damage to skeletons was not large, but in one observed case, a multi‐story wall in an apartment house was probably bored by debris impact .
Yasuo Okuda 40 (3) Overturning
One case, in which a whole building including foundation is overturned, was confirmed. Most of the ALC panels of claddings were left.
Yasuo Okuda 41 (4) Collapse
Damage cases of skeleton collapse include story collapse of the first floor in a 2‐ story steel building and partial collapse of a warehouse on the coast.
Yasuo Okuda 42 (5) Large residual deformation
Slight tilting was often observed in steel buildings with only a skeleton left. In one case, a gabled roof frame building did not collapsed despite large residual deformation. Yasuo Okuda (6) Full fracture and washed away of 43 cladding and internal finishing materials
Cladding materials such as ALC panel were almost fully fractured and washed away, and a steel frame as a skeleton was left. This case was often seen.
Yasuo Okuda Damage to wood houses (1) 44
In the case of a maximum inundation depth more than about 6 m (equivalent to a height of eaves of 2‐story wooden house), the number of 1‐story and 2‐story Wood Houses that remained was almost zero. In the case of a maximum inundation depth of about 1 m, most of wood houses remained.
Yasuo Okuda Damage to wood houses (()2) 45
GSI
A tsunami wave force was reduced possibly due to many openings in the direction affected by tsunami or on the whole plane, or a wooden house remained despite washout of columns and external walls in the corner of the building. Yasuo Okuda Database for Investigated Buildings 46
Outer dimensions of about 100 buildings and dimensions of their skeletons were measured in the site investigation. Building name, address, purpose, construction year, designation as tsunami evacuation building, structure category, number of stories, outer dimension, distance from seacoast (river), GPS posiiition, aliltitud e, surrounding circumstances, damage situations, etc., were included in the database.
Yasuo Okuda Discussion on Guidelines for Tsunami Evacuation47 Buildings by the Cabinet Office, Japan
In the Cabinet Office guidelines, the design tsunami load for the tsunami evacuation buildings was adopted as the tsunami wave pressure eq. (1), hydrostatic pressure of 3 times design inundation depth, based on the maximum envelope of the experimental result in Japan. Yasuo Okuda Damage Situations of Buildings and Structures 48 with Some Obstacles for Tsunami Effect A depth ratio is defined as eq. (2).
ηe (2) a = ηm
a : depth ratio
ηe : depth of the hydrostatic pressure equivalent to the strength of the buildings and structures (m)
ηm : measured inundation depth (m)
This figure plots damage situations of buildings and structures with some
obstacles for tsunami effect for a and ηm. A boundary line of damage situations of buildings and structures can be drawn at the depth ratio a =1 where ηm<10m. Yasuo Okuda 49 CliConclusions
This section’ s conclilusions are as fllfollows; 1) The damage patterns for different structural categories were classified and the factors that had caused various types of damage were briefly discussed. 2) The database of the investigated buildings and structures was made. 3) Based on the database, we plotted the damage situations of the investigated buildings and structures for the measured inundation depth and the depth ratio. A boundary line of damage situations of buildings and
structures can be drawn at the depth ratio a =1 where ηm <10m.
Yasuo Okuda 50
4. Ground Motions of the Tohoku earthquake and Recent Activity on Long‐period Motions for Design of Building Structures By Okawa, Izuru 51 The 2011 off the Pacific coast of Tohoku Earthquake 44˚
43˚ IJMA 7 6 5 42˚ 4 3 2 1 41˚
40˚
39˚
38˚ Mainshock 37 2011/03/11 14:46 ˚ (h=24km, Mw9.0)
36˚
km 35˚ 0 100 200 34˚ 1 ˚ 34˚ 135˚ 136˚ 137˚ 138˚ 139˚ 140˚ 141˚ 142˚ 143˚ 144˚ 145˚ 146
Izuru Okawa Examples of observed motions 52
3000 Acceleration 500 Pseudo Vel. Resp.Spectrum (h=5%) 2 0 0 N-S (peak: 2679 cm/s ) 00 00 0 1 ) 1 2 138˚ 139˚ 142˚ 143˚ 0 140˚ 141˚ 0 (cm/s 10
40˚ 100 10 -3000 0 3000
E-W (peak:- 1285 cm/s2) onse (cm/s)
) 50 2 0 (cm/s
) /s -3000 /s cm 3000 10 ( 1 U-D (peak: 1886 cm/s2) 10 0 ) 2 Pseudo Velocity Resp 39˚ 0 5 N-S 0
(cm/s .1 E-W ( cU-Dm 1 -3000 2 ) 0 20 40 60 80 100 120 140 160 180 200 0.1 0.5 1 5 10 K-NET Tsukidate (7) Time (sec) Period (sec) MYG004: K-NET Tsukidate Pseudo Vel. Resp. Spectrum (h=5%) 3000 Acceleration 500 2 0 00 N-S (peak: 1520 cm/s ) 00 0 0 1 ) 1 2 0 38˚ 0 (cm/s 10
100 10 -3000 0 3000
E-W (peak: 987 cm/s2) onse (cm/s) K-NET Sendai (6+ ) pp
) 50 2 0 (cm/s
) /s -3000 /s 3000 cm 10 0( 1 37˚ U-D (peak:- 299 cm/s2) 1 0 ) 2 Pseudo Velocity Res 0 5 N-S 0 K-NET Hitachi (6+ ) (cm/s .1 E-W ( cU-Dm 1 -3000 2 ) 0 20 40 60 80 100 120 140 160 180 200 0.1 0.5 1 5 10 Time (sec) Period (sec) MYG013: K-NET Sendai Pseudo Vel. Resp. Spectrum (h=5%) 3000 Acceleration 500 2 00 00 N-S (peak:- 1599 cm/s ) 0 0 0 1 ) 1
36˚ 2 0 0 (cm/s 0 1
100 10 km -3000 0 3000 E-W (peak:- 1187 cm/s2) ponse (cm/s) 50 )) ss 2 0 50 100 0 (cm/s
) /s 35 ˚ -3000 /s 3000 cm 10 0( 1 U-D (peak: 1159 cm/s2) 1 0
138˚ 139˚ 140˚ 141˚ 142˚ 143˚ ) 2 Pseudo Velocity Re 0 5 N-S 0
(cm/s .1 E-W ( cU-Dm 1 -3000 2 ) 0 20 40 60 80 100 120 140 160 180 200 0.1 0.5 1 5 10 Time (sec) Period (sec) IBR003: K-NET Hitachi
Izuru Okawa 53 BRI Strong motion observation network (Instrumentation in Buildings)
44˚
43˚ HKU KGC HRO 36˚20' 42˚ HKD 41˚ ANX, BRI HCN2, HCN TKC 40˚ HRH NIT 36˚00' AKT MYK 39˚ SITA, SIT2 TUS TRO UTK, 2011/03/11 NMW, TDS MST 38˚ NIG 14:46(JST) AKB THU, SMD ADC SND h=24 km, M9.0 EDG KDI NKN YCY FNB 37˚ IWK 35˚40' TKD ICK CGC, CHB NGN CG2, TUF 36˚ CG3 MIZ KWS KSO YMN km 3 NGY 5˚ OSK, SMZ km SKS 0 50 MTS SMS 0 100 200 35˚20' 34˚ 139˚20' 139˚40' 140˚00' 140˚20' 140˚40' 1 ˚ 34˚ 135˚ 136˚ 137˚ 138˚ 139˚ 140˚ 141˚ 142˚ 143˚ 144˚ 145˚ 146 Izuru Okawa 80 60 1978.6 Miyagi-ken-oki Eq 54 Tohoku 40 cm/s) 20 university 0
Velocity ( -20 2011.3 .11 Tohoku Eq Eq. (main (main shock) shock) -40 0 50 100 150 200 250 300 time (s)
1000
) (a)Acc.inTrans.Dir. 09F(Trans.) 2 01F(Trans.) 0 Acc (cm/s −1000 1000
)) (b) Acc. in Long. Dir. 09F(Long.) 2 01F(Long.)
cm/s 0 Acc ( −1000 40 (c) Bldg. Disp. in Trans. Dir. ) mm 0 Disp (c −40 40 (d) Bldg. Disp. in Long. Dir. ) mm 0 Disp (c −40 2.0 (e) Transition of natural periods 1.5 s) ((
T 1.0 Trans Long. 0.5 0 50 100 150 200 Izuru Okawa Time (s) 50 Displacement 01F S-N (peak:- 20.5 cm) 0 55 Disp. (cm) -50 50 01F W-E (peak:- 17.6 cm) 0
Disp. (cm) -50 50 ) 37F S-N (peak:- 32.1 cm) mm 0
Disp. (c -50 50 37F W-E (peak:- 27.9 cm) (cm)
.. 0
Disp -50 50 37F-01F S-N (peak:- 14.7 cm) 0 sp. (cm) ii D -50 50 37F-01F W-E (peak:- 16.7 cm) 0
Disp. (cm) -50 0 100 200 300 400 500 600 700 Time (s)
Skyscraper on Tokyo Bay Izuru Okawa 56 Skyypscraper on Osaka Bay, tallest in western Japan, with more than 700 km epic. distance.
Osaka Sakishima office
Izuru Okawa 57 Skyscraper on Osaka Bay
52 fl. Osaka Sakishima office
38 fl. 256m
Y
18 fl.
1fl1 fl. Sensor locations on the plan accelerometer Izuru Okawa Osaka Sakishima Office Building
) 58
2 2011 off Pacific coast of Tohoku Eq. s Max.126 gal
// 100 52F 0 -100 ACC(cm 0 200 400 600 800 1000 （秒） ) 2 100 Max. 86 gal 38F 0 (cm/s
CC -100 AC 0 200 400 600 800 1000
（秒） X )) 2 100 0 Max. 41 gal
18F C(cm/s -100 CC A 0 200 400 600 800 1000 )
2 （秒） s 100 Max. 34 gal 0 -100
1F ACC(cm/ 0 200 400 600 800 1000
accelerometer (s) Izuru Okawa 140 h=0.05 59
Akita pref. office B1F Pseudo velocity spectrum 120 Hachinohe city hall GL Iwaki city hall B1F Miyako city hall GL 100 Niigata city hall B1F of observed motions Sendai Gov. Bldg B2F BSL design bedrock motion
city (cm/s) city 80 oo
60 44˚ 40 Pseudo Vel Pseudo 43˚ HKU KGC 20 HRO 42˚ HKD 0 41˚ 0 2 4 6 8 10 Period (s) HCN2, HCN HRH 40˚ 120 AKT MYK Adachi Gov. Bldg, 01F 39˚ University Bldg, Kasukabe_GL TRO 100 Saitama Gov. Bldg No.2, 01F 2011/03/11 Misata cit y hall, GL 38˚ NIG THU, 14:46(JST) TUS, Noda, 01F SND h=24 km, M9.0 BSL design bedrock motion 80 37˚ IWK NGN 60 36˚ (cm/s) locity MIZ ee KSOYMN 3 NGY 5˚ OSK, SMZ km 40 SKS SMS 0 100 200 MTS v Pseudo 34˚ 1 ˚ 20 34˚ 135˚ 136˚ 137˚ 138˚ 139˚ 140˚ 141˚ 142˚ 143˚ 144˚ 145˚ 146
0 0 2 4 6 8 10 Izuru Okawa Period (s) MLIT & NILIM proposal for tentative measures for 60 the safety of hhhigh‐rise bldbuildings Background ∗ Fire of large oil storage tank due to the effect of long‐period earthquake motions ∗ Concerns of the effect of Long‐period earthhkquake ground motions to high‐rise and SI buildings ∗ Earthkhquake occurrence probbbiliability is high for major subduction‐zone earthquakes such as Nankai, Tonankai and Tokai earthquakes ∗ Various projects on earthquake damage evaluations for subduction‐zone earthquakes ∗ MLIT funding for safety measures for long‐period buildings (Selected Research Group + BRI)
Izuru Okawa Design earthquake motions for high‐rise buildings 61
'50 '6 '70 '8 '9 '0 '10 0 0 0 0 EQ. Recordings
1968 Tokachi 1978 Miyagi‐oki 1995 Kobe 2003 Tokachi
Building Standard New Design method Revision
Design Seismic force Design Motions
Design High‐rise buildings motions for Base‐isolated buildings high‐rise Time history buildings Design spectra Notification wave
Recorded motions Max. velocity Regional design motions Level 1 Max. acc. 25 cm/s BCJ Guidelines Level 1 Level 2 Site‐specific design motions 200～300 gals 50 cm/s Long‐period Impulse Level Long period wave 300～500 gals Long duration Design criteria （Story drift angle, Ductility factor, etc） El Centro, Taft, Hachinohe Energy StSpectra Prediction method (long and short period) Empirical method Fault Rupture (asperity etc.) Precise methodology Damage Estimates
Probabilistic Map
Long‐period Map 62 ∗ Design Motions Currently Used for Tall Buildings (>60m) 1. BSL Notification spectrum compatible motions (Fig.1) 2. Modified Recorded motions (Vmax=25,50cm/s) 3. Site‐specific motions
2 h=0.05
100 /s) 8 mm 6
4 4 BCJ L2 Engineering Bedrock BSL E.B.
elocity (c elocity 2 BSL Soil 1 2 m/s)
VV BSL Soil 2 BSL Soil 3 10 0 8 6 Pseudo Pseudo 4 -2 Acceleratio ( Acceleratio
2 -4 5 6 7 2 3 4 5 6 7 2 3 4 5 6 7 0.1 1 10 0 20 40 60 80 100 120 Period (s) time (s) Fig.1 BCJ (L2) and BSL Design Spectra and BSL wave for Engineering Bedrock
Izuru Okawa 63 GGoudround motio n para mete r s aadnd ppedctorediction model
1. Spectral Properties 1) Acceleration response spectrum (h=0.05, 0.01) 2) Energy Spectrum (h=0.10) 3) Site amplification coefficient 2. Time history Properties 1) Site factors with phase properties controlling waveforms and duration time
Izuru Okawa 64 Used Earthquake Data（Subduction, Crustal Eqs.）
Subduction Crustal ・Subduction：Mj≧656.5, Hypocentral dist.≦400km ・Crustal：Mj≧606.0, Hypocentral dist. ≦350km ・Focal depth≦60km Mj：JMA magnitude
K‐NET, KiK‐net, JMA data were used in this study
64 Izuru Okawa Site amplification 65 coefficient Cj(T)
OSKH02
Site amplification coefficient at T=5 sec.
Izuru Okawa 66 Site amplification factors for Sa(5%) horizontal components
3 sec. 7 sec. 9 sec.
Izuru Okawa 67 Simulated ground motion for large earthquakes
Mw8.0
Mw8.2 Mw8.2 Mw8.4
(a)(a) Nankai 想定南海地震 earthquake (b)(b) 想定東海・東南海地震 Tokai‐Tonankai earthquake
Izuru Okawa Simulated ground motion for Nankai earthquake68
h=5% BSL : Notification spec Case 2 : Average+ ERR Case 1 : Average+ ERR Case 2 : Average Case 1 : Average Kamae Tsurugi Sekiguch i
(a) 既往の予測波 (b) 本研究の予測波
速度波形：乱数 1 釜江波Kamae
速度波形：乱数 2
鶴来波Tsurugi
関口波Sekiguchi 加速度波形：乱数 1
Izuru Okawa Simulated ground motion for Tonankai‐Tokai earthquake69
NST site (Sato,200 6)
佐藤・他(2006)：NST 工学的基盤
回帰式の平均値を用いた場合：乱数Case 2 : Average 2
本研究：AIC004AIC004 Surface 地表
群遅延時間の平均値と標準偏差の回帰式のCase 2 : Average +ERR (a)NST 既往の予測波 site (佐藤・他,2006) This(b) 本研究の予測波 study 平均値－ 回帰誤差 e を用いた場合：乱数 2 (Sato,2006)
AIC004本研究： AIC004Surface地表 Mw8.0 Mw8.2
Izuru Okawa 70 MLIT ppproposal for tentative measures for the safety of high‐rise buildings ∗ With MLIT ffdunding, the methdlhodology is constructed. ∗ Long‐period earthquake ground motions for specific sites can be evallduated ildiincluding time histori es. ∗ Earthquake motions for verification generated for three major subducti on‐zone earthquak es →Nankai, Tonankai and Miyagi‐oki earthquakes ∗ Long‐period earthquake motions for 9 zoning sites in urban area were proposed for existing and new ones. ∗ Public comments to this proposal were invited. ∗ The 2011 Tohoku earthquake occurred.
Izuru Okawa 71 Nine Zonings in Urban Areas
Osaka Nagoya Tokyo
Izuru Okawa 72 Area 9 (ti(representing TTkokyo Bay area)
Izuru Okawa 73 MLIT ppproposal for tentative measures for the safety of high‐rise buildings ∗ With MLIT ffdunding, the methdlhodology is constructed. ∗ Long‐period earthquake ground motions for specific sites can be evallduated ildiincluding time histori es. ∗ Earthquake motions for verification generated for three major subducti on‐zone earthquak es →Nankai, Tonankai and Miyagi‐oki earthquakes ∗ Long‐period earthquake motions for 9 zoning sites in urban area were proposed for existing and new ones. ∗ Public comments to this proposal were invited. ∗ The Tohoku earthquake occurred.
Izuru Okawa 74
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