2. Date and time Friday, March 11, 2011
02:46:23 PM - Local Time
Epicentre 38.322oN and 142.369oE
Magnitude 9
Intensity Up to VII
Peak ground
acceleration
2g to 0.34 g
Characteristics
2
3. Peak ground
acceleration
2g to 0.34 g
Foreshocks and
aftershocks
About 50 (5 of magnitude >7)
Energy released Earthquake 1.9 0.5 X 1017 J
Total including tsunami 3.9 X 1022 J
Velocity of
tsunami wave
700 kilometers per hour
Characteristics
3
4. Ring of fire
Plate movement
Pacific plate slipped beneath Eurasian plate
It was moving a few cm every year
4
10. Impacts
• Infrastructure
» Power, nuclear, railway, air port,
ports
• Economic
» Total loss $ 171 to 183 billion
» Total cost of recovery $ 122 billion
10
11. Nuclear crisis
• Crisis at Fukushima
• Level 7 nuclear event
• What happened?
• The height of sea wall was insufficient
• Power system was poorly designed
• IAEA norms – Design to consider events
having probability of 1 in 10,000 years
11
12. Damage to structures
Prestressed Concrete Institute (PCI) report
• No widespread structural damage
• Damages mainly from tsunami, not shaking
• Major damages due to quake suffered by old
buildings built before code revisions.
• Several changes to building codes in last 40
years, after 1968 earthquake
12
13. Code revisions
Review procedure for existing buildings for seismic
safety.
Reduced the spacing of steel ties in columns to 100 mm
Ultimate strength design for shear of beams and
columns
More stringent requirements for shear reinforcement
Two phase design
i. 0.08 g to 0.1 g (can occur several times)
ii. 0.3 g to 0.4 g (Can occur once in the lifetime of
building)
Performance based seismic design introduced in 2000
13
15. Preparedness
Many measures by Japan after 1995 earthquake
World’s first earthquake early warning system
Rapid and systematic and calm reporting by
media
Heavy investment in educating public about
disaster management
One of the most stringent construction
standards
The highest disaster risk aware population
15
16. • Very old timber houses are generally collapsed.
• Damage is generally limited to roof with tiles.
• Damage to timber houses built on a soft ground or
nearby creeks or rivers.
Damages to timber buildings
16
17. Damages to masonry buildings
o Damage is generally limited to roof with tiles.
o As the number of masonry buildings are few, no
major collapses were observed 17
18. Damages to RC buildings
Complete collapse of a few buildings built before
code revisions 18
22. Shiogama Municipal No. 2 Junior High School retrofitted using an
external precast concrete frame braced with tension ties 22
23. 1. Okada Norio et. al. (2011), “The 2011 Eastern Japan Great
Earthquake Disaster: Overview and Comments”, Int. J.
Disaster Risk Sci., 2 (1): 34–42
2. Richard Sause et. al, “Preview of PCI’s Japan earthquake
Reconnaissance Team Report”, www.pci.org
3. Ömer Aydan and HisatakaTano (2011), Shaking – induced
damage to buildings by M 9.0 East Japan mega earthquake
on March 11, 2011
4. Ömer Aydan and HisatakaTano (2011), Liquifaction-induced
damage to buildings by M 9.0 East Japan mega earthquake
on March 11, 2011
5. www.sefindia.org
6. www.jsce-int.org
References
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