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Damage of Bridges Resulted from

March 11, 2011 East-JapanEarthquake

Kazuhiko KawashimaDepartment of Civil Engineering

Tokyo Institute of Technology

April 15, 2011


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Introduction

This slide set shows damage of transportationfacility due to the East-Japan earthquake,March 11, 2011. The field damageinvestigation was conducted on March 29-Arpril 3, 2011 by the author with other 12members of the Japan Society of CivilEngineers reconnaissance damageinvestigation team. The cooperation of the

team members is greatly acknowledged. Theview shown here is that of the author, anddoes not necessarily represent the view of

Japan Society of Civil Engineers.


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After-shock AreaBetween 12:00, March 11 and 12:00, March23 by JMA


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Preliminary Analysis of the Fault

Mechanism by NIEDDirection 195 degree

Dip 13 degreeSize 501kmX

Maximum slipMw=8.9

NIED


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K-NET StrongMotion Records

NIED


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Response Spectrum at Tsukudate whereResponse Spectrum was the highest

A c c e

l e r a

t i o n

( m / s 2 )

Time (s)

-10

0

10EW

-20

0

20 NS

-10

0

10

20UD

0 5 10

Period (s)

EW

NS

UD

R e s p o n s e

A c c e l e r a

t i o n ( m

/ s 2 )

0

20

40

60

80

100

120

140

0 1 2 3 4


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Comparison with 2 typical near-field

ground motions during the 1995 Kobe,Japan earthquake JMA Kobe & JR TakatoriStation

Period (s)

R e s p o n s e

A c c e

l e r a

t i o n

( m / s 2 )

0

20

40

60

80

100

120

140

0 1 2 3 4

JMA-Kobe, 1995 Kobe EQ

Takatori, 1995 Kobe EQ


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0

20

40

60

80

100

120

140

0 1 2 3 4

Type IType IIType III

Comparison with Type II Design

Spectra, JRA Design Specifications ofBridges

Period (s)

R e s p o n s e

A c c e l e r a

t i o n ( m

/ s 2 )


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Tsunami Height measured by JMA

1m

2m

3m

4m

5m Maximum at Soma: 7.3m

Local tsunami height is being investigated.

It is reported that tsunami run up 23 m at asite in Ofunato City.


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Kesen-numa

CityFrom Kesen-numa JuniorHigh School


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Kesen-numa City


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Field damage investigation for

bridges was conducted focusing onthe following issues:

Was the ductility capacity method whichwas enforced in design of road bridges since1990 effective for mitigating damage?

Was the extensive use of elastomericbearings since 1995 Kobe earthquake

effective for mitigating damage of bearings?What types of damage occurred to bridges

due to tsunami?


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Sendai Bridge (Route 4)

Seismic performance of bridges supportedby elastomeric bearings

hin-T nn Bri nrik Ex r w


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Iinogawa Bridge, Route 45

Higashi Matsuyama Bridge, Route 45

Bridges supported by elastomeric

bearings did not suffer damage


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Tenno BridgeRoute 45

Main bridge

Pull-out of

Anchor Bolts

Pedestrian bridge

Existing damage still continued to

occur in the bridges supported byexisting steel bearings


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Rupture of Elastomeric Bearings Occurred

at Two Locations Close Each OtherEast Sendai Road -East


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NEXCO-East


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Bearings Damaged

Separation of a rubber layer and a steel pl

The steel platebent in double

in a complexmanner


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How large shear strain was induced in the

rubber layers?Was the bearing properly fabricated?

Separation of

rubber layersfrom steel platesdid not occur in

the past


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Unretrofitted

Shinkansen columnssuffered extensivedamage


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Extensive Damage of Shinkansen Viaductduring 2003 Miyagi-ken-oki earthquake


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Kesen Bridge

Kesen BridgeRoute 45Rikuzen-Takada City

The superstructure waswashed away 310 m

upstream


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Parapet-wall of

the right abutment

Damage ofparapet-wallresulted when thedeck was washed-

away

Ruptured elastomeric bearing

Failed side-block

Damage of Bearings and Side-Blocks

at the Right Abutment


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Right abutment

Failed elastomeric bearings

Four dampers

Four dampers atthe rightabutment

Damage of Dampers

Installed for SeismicRetrofit


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Utazu BridgeRoute 45Rikuzen-Takada City


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Some cable restrainerswere still alive

Installed in 2005 forseismic retrofit


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Steel stoppers were provided, but theywere ineffective for preventing transversedeck movement & uplift by tsunami

There was an end-blockhere, but it was insufficient

for preventing transversedeck movement RC side blocks were used, butthey were also insufficient


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Koizumi BridgeRoute 45Rikuzen-Koizumi

A1 P1 P2 P3 P4 P5 A2

3-span continuous 3-span continuous

Two 3-span continuous plate girder bridges

P3 was washed away


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Superstructure 1

350 m upstream

Two 3-span continuous superstructureswere washedaway upstream

A h


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Anothersuperstructure waswashed away 450mupstream at the left

side bank

Second bridge

Trace left onthe left dykeshowing thatthe bridge was

washed alongthis line


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A1P1

P2

P3 must be somewhere around here

Damaged steel

bearings on P2


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Support condition of a bridge on A2

abutment

Sliding bearing

Collapsed side block

Cable restrainers

Four dampers forseismic retrofit

Shi Kit k i B idg


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Upstream

Upstream

Shin-Kitakami BridgeRegional Road over Kitakami River


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Full of Debris on the Deck

Deck floors of a side pedestrian bridge


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Deck floors of a side pedestrian bridge(upstream side) uplifted to rotate by 90degree from the girders

Jibbers forconnection

Tsunami flowThey contributedto increasing ofwater pressure

Abutment seat from where the span felt


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Damaged base

plate of aroller bearin

Roller bearing whichsupported the un-collapsed bridge

Abutment seat from where the span felt


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Two piers and the left side abutmentdid not suffered damage

Numata Over Bridge


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Numata Over BridgeRopute 45Rikuzen-Takada City

Six longitudinal stoppers were provided. Theymust be effective to prevent transversemovement of the deck.

Unless the decks were uplifted by tsunami, thisfailure could not happen.

Embankment


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Embankmentwas completelywashed away,and an abutment

was left alone

There were a number of bridges which did


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There were a number of bridges which didnot suffer damage by tsunami, but backsoils & embankment were washed awayKawahara River Bridge

Route 45Rikuzen-Takada City

The two story building


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Abutment

Embankmentwhich waswashed away

Bridge The buildingwhich hit thebridge

Temporal bridge

y ghit the bridge, but the

bridge survived

Embankment was


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Cables embeddedin the embankment

Anchors of cablerestrainers

Kawahara River Bridge

A two storybuilding

completely

washed away

Furukawa Bridge (Pedestrian Bridge)


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g ( g )Takada-no-matsubara Park

Rikuzen-takada City

Nijyu-ichi Hama Bridge


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Nijyu ichi Hama BridgeRoute 45Kesen-numa City

EmbankmentEmbankment

Many short bridges survived tsunami


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y g

A Bridge onRoute 45Shizu-gawa town

Guard Railswere washedaway

Damage of the town around the bridge

Minato Bridge


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150 m downstream of the bridge in the previous

slideShizu-gawa town

This bridge suffered minor damage

Sho-nin Bridge


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Route 45Ofunato City

Damage of the city 100 mupstream the Sho-nin Bridge

Failure Bridges due to Scouring


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Tsunami

Failure Bridges due to ScouringThis failure mode was not observed during

the East-Japan earthquake since foundationswere deep and well constructed

A ibl F il M h i f


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Tsunami hydropressure

A possible Failure Mechanism ofBridges due to Tsunami

b bl l h


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Tsunami hydropressure

Failure ofdownstreambearing due touplift force

Larger hydropressure

Most Probable Failure Mechanismof Bridges due to Tsunami

Preliminary Findings


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Preliminary Findings

Bridges which were constructed or wereretrofitted based on the ductility designmethod (enforced since the 1990 JRA DesignSpecifications) suffered almost no damage. Itcontributed to the enhancement of the seismicperformance of bridges.

Elastomeric bearings including lead rubberbearings and high damping rubber bearingswhich were introduced since 1990s mitigateddamage of bearings. However severalelastomeric bearings ruptured at two locationsof East Sendai Expressway. Reason of thedamage has to be clarified.

Preliminary Findings (2)


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A number of bridges suffered damage bytsunami. Damage was possibly developed by

deck rotation toward upstream side, resultedfrom uplifting force. If failure of bearings(particularly downstream side bearings) due touplifting force can be prevented, damage oftsunami may be mitigated.

It is recommended to install unseating

prevention device for tsunami. Restrainerswhich are widely used for unseatingprevention device for earthquake may be

effective if they are set in the vertical direction.

Preliminary Findings (2)

Acknowledgements


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g

Deep appreciation is given to Nishioka, T.(Hanshin Expressway Co.), Akiyama, M.(Waseda Univ.), Takahashi, K. (Kyoto Univ.),

Watanabe, G. (Yamaguchi Univ.), Matsuzaki, H.(Tokyo Institute of Technology) and Koga, H.(PWRI) as well as Wakamatsu, K. (KantoGakuin Univ.) and other members of JSCEreconnaissance team. Appreciation is extendedto Ministry of Land, Infrastructure andTransportation, Nexco-East, JR-East, Tahahashi,H., Sakamoto, S. & Kimata, K. (ShimizuConstruction Co.), and Yabe, M. (ChodaiConsultants). Support of WFEO Disaster RiskManagement Committee is acknowledged.

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