Preliminary Information on the 2003 Tokachioki Earthquake

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Preliminary Information on the 2003 Tokachi-oki
Earthquake

• Yohsuke Kawamata and Professor Scott Ashford
• Department of Structural Engineering
• University of California, San Diego

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References for Slides
1, 3 http//earthquake.usgs.gov/ USGS
2, 4 http//www.k-net.bosai.go.jp/k-net/
Khoshin Network, K-Net, National Research
Institute for Earth Science and Disaster
Prevention, Japan
http//www.hkd.mlit.go.jp/ Hokkaido Regional
Development Bureau for background information.
Acknowledgement
We are indebted to Dr. Sugano, head of
Structural Dynamics Division in Port and Airport
Research Institute (PARI) , Japan, and Dr.
Kohama, researcher of Structural Dynamics
Division in PARI for some pictures and data. We
would like to express sincere gratitude to
them.Web-site of PARI, Japan
http//www.pari.go.jp/
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Tokachi-oki Earthquake, 2003
Basic Information Time (in JAPAN) 450a.m.
Sep. 26/2003 Location of epicenter
Latitude 41.827N Longitude 143.830E Depth of
focus 33km Magnitude 8.3
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Peak Acceleration in each Region
Peak Acceleration (Gal)
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The second largest Earthquake
Basic Information Time (in JAPAN) 608a.m.
Sep. 26/2003 Location of epicenter
Latitude 41.831N Longitude 143.496E Depth
of focus 33km Magnitude 7.4
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Peak Acceleration in each Region
Peak Acceleration (Gal)
7
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Mechanism of Tokachi-oki Earthquake, 2003
Focus
Plate (Land-side)
Sea
Trench
The Pacific Plate
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The Damage of Sewerage Structures
Toyokoro
Trace of Sand Boilingnear Lifted-up Manhole
Lifted-up Manhole
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The Damage of Sewerage Structures
Kushiro (town)
Lifted-up Manhole and gushed Soil during
Liquefaction
Lifted-up Manhole
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The Damage of Sewerage Structures
Place where Lift-up of Manhole is observed
Kushiro
Akan (4)
Hamanaka (several, about 20cm)
Kushiro (dozens, 30-100cm)
Ombetsu (25)
Kushiro(town) (dozens, max
about 200cm)
Taiki
Urakawa
Toyokoro (30, max90cm)
(the number, height of lift-up)
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The Damage of Sewerage Structures
Failure Mode (notice this is only concept)
Sand Boiling
Sand Boiling
Flexible Pipe
Manhole
Crack or Residual Strain
Residual Strain
Original Soil (Liquefied)
Rigid Pipe
Lift-up Force
Replaced Soil (Liquefied)
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The Damage of Embankment Structures
Toyokoro
Collapsed Embankment
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The Damage of Embankment Structures
Collapsed Embankment
Liquefied Soil
Liquefied Soil
Toyokoro
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The Damage of Embankment Structures
Place where Embankment was collapsed
Lateral Spread was observed
Under investigation
( ) the number of collapsed points
Abashiri River (1)
Shibetsu River (6)
Kushiro River (5)
Tokachi River
Kiyomappu River (2)
Tokachi River (66)
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The Damage of Embankment Structures
Failure Mode (notice this is only concept)
Settlement
Embankment
Land Slide
Liquefied Stratum
Lateral Spread
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The Damage of Port Structures (at Kushiro Port)
Kushiro
Settlement behind Quay Wall
Crack
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The Damage of Port Structures (at Kushiro Port)
Kushiro
Trace of Sand Boiling
Settlement behind Quay Wall
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The Damage of Port Structures (at Tokachi Port)
Tokachi
Settlement around Terminal Building
Sand Boiling
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The Damage of Port Structures (at small Fishing
Port)
Taiki
Face Line of Quay Wallmoved to sea-side
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The Damage of Port Structures
Port where Liquefaction was observed (excluding
small fishing port)
Tokachi Port
Nemuro Port
Kiritappu Port
Kushiro Port
Tomakomai Port
Shiraoi Port
Tokachi Port
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The Damage of Port Structures
Failure Mode (notice this is only concept)
Crack
Sand Boiling
Settlement
Displacement
Reclaimed Soil(Liquefied)
Caisson
Back-filled Gravel
Mound (Gravel)
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The Damage of Bridge Structures
Tokachi-kako Bridge
Toyokoro
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Introduction of other Web-sites
on Tokachi-oki Earthquake
The Hokkaido Shimbun Press http//www.hokkaido-n
p.co.jp/