What happens during liquefaction (Soil Liquefaction web site, University of Washington)

1. What happens during liquefaction (Soil Liquefaction web site, University of Washington)

2. Liquefaction, 1964 Niigata earthquake, Japan (Soil Liquefaction web site, U-Wash)

11. Liquefaction damage, Marina District, San Francisco

12. Liquefaction damage, Marina District, San Francisco Sand boil

13. Resonance

16. Period (seconds) ~ 0.1 × Number of floors

17. 5 floors 1 floor

19. 1985 Mexico City earthquake 10,000 deaths 50,000 injuries $5 billion damage Maximum Intensity IX 350 km away! MW≈ 8.0

20. Attenuation High frequency: treble Low frequency: bass

21. Amplification

22. 8-18 stories most damage 1-2 Hz vibrations Resonance Visuals Unlimited

23. Liquefaction

24. Earthquake Prediction

25. Gap Gap filled by earthquake Seismic Gap Theory

26. Elastic Rebound Theory

27. Elastic Rebound Strain No strain built up, quakes unlikely

28. Elastic Rebound Strain Strain building up, quakes more and more likely

29. Elastic Rebound Strain Long time since last quake; quake likely

30. Elastic Rebound Strain Quake!Occurs as strain is released by rocks breaking

31. No strain in rocks, quakes unlikely Elastic Rebound Strain

32. Same fault, different segments; behave differently

33. Earthquakes in past 50 years Seismic Gap

34. Earthquake and aftershocks: gap filled

35. San Andreas Fault segments have different quake probabilities Probability of quake USGS

36. Creeping Faults

37. Earthquakes triggering Earthquakes North Anatolian Fault, Turkey

41. The Most Damaging Earthquakes

49. Bam, Iran, prior to 2003 M=6.6 earthquake

50. Bam, Iran, after 2003 M=6.6 earthquake