1. Seismology and Earthquake Engineering :Introduction

2. Engineering for Earthquakes Earthquake Seismic Waves Geologic Effects Structural Response Losses Hazard Analysis Seismologists Geotechnical Engrs Response Analysis Geotechnical Engrs Structural Engrs Loss Analysis Structural Engrs Loss Analysts

3. The Earth (outside)

4. The Earth (inside) Hot Cold

5. Convection

6. Convection

7. Plates 6 continental size 14 sub-continental size

8. Plates White: Political boundaries Yellow: Plate boundaries Red: Epicenters

9. Based on continental shelves Plates

10. Plates

11. Plates

12. Plates

13. Plate Boundaries Spreading Ridge Boundary

14. Spreading Ridge

15. Eastern Pacific Ridge

16. Spreading Ridge Thingvellir

17. Plates Subduction Zone

19. Plates Transform Boundary

20. Transform Boundaries Carrizo Plain Crystal Spring Reservoir

21. Faults Main types: Normal Faulting

22. Faults Main types: Reverse Faulting

23. Faults Main types: Strike Slip Faulting Calaveras Fault

24. Basic Concepts of Seismology Elastic rebound theory Plates are in continuous motion Stresses and strains build up near boundaries Strain energy stored in crust near faults, then released Aseismic movement - slow creep in ductile rock Seismic movement - rupture of brittle rock

25. San Francisco Portola Valley Loma Prieta Gap Parkfield San Juan Bautista Loma Prieta Basic Concepts of Seismology Seismic Gaps 1969-89 seismicity

26. San Francisco Portola Valley Loma Prieta Gap Parkfield San Juan Bautista Loma Prieta Loma Prieta earthquake and aftershocks Loma Prieta earthquake and aftershocks Basic Concepts of Seismology Seismic Gaps

27. Basic Concepts of Seismology Seismic Gaps

28. Basic Concepts of Seismology Near-field effects “Fling” Rupture moving away from observer Rupture moving away from observer Rupture moving toward observer Rupture moving toward observer

29. Basic Concepts of Seismology Near-field effects “Directivity” Fault parallel Fault parallel Fault normal Fault normal Fault normal accelerations exceed fault parallel accelerations Fault normal accelerations exceed fault parallel accelerations

30. Basic Concepts of Seismology Earthquake size Intensity - qualitative measure of observed effects Modified Mercalli Intensity (MMI) MMI IV During the day felt indoors by many, outdoors by few; at night some awakened; dishes, windows, doors disturbed; walls make cracking sound; sensation like heavy truck striking building; standing motor cars rocked noticeably MMI IV During the day felt indoors by many, outdoors by few; at night some awakened; dishes, windows, doors disturbed; walls make cracking sound; sensation like heavy truck striking building; standing motor cars rocked noticeably

31. Basic Concepts of Seismology Earthquake size Intensity - qualitative measure of observed effects Modified Mercalli Intensity (MMI) MMI IV During the day felt indoors by many, outdoors by few; at night some awakened; dishes, windows, doors disturbed; walls make cracking sound; sensation like heavy truck striking building; standing motor cars rocked noticeably MMI IV During the day felt indoors by many, outdoors by few; at night some awakened; dishes, windows, doors disturbed; walls make cracking sound; sensation like heavy truck striking building; standing motor cars rocked noticeably MMI VII Everybody runs outdoors; damage negligible in buildings of good design and construction, slight to moderate in well-built structures, considerable in poorly built or badly designed structures; some chimneys broken; noticed by persons driving motor cars MMI VII Everybody runs outdoors; damage negligible in buildings of good design and construction, slight to moderate in well-built structures, considerable in poorly built or badly designed structures; some chimneys broken; noticed by persons driving motor cars

32. Basic Concepts of Seismology Earthquake size Intensity - qualitative measure of observed effects Modified Mercalli Intensity (MMI) MMI IV During the day felt indoors by many, outdoors by few; at night some awakened; dishes, windows, doors disturbed; walls make cracking sound; sensation like heavy truck striking building; standing motor cars rocked noticeably MMI IV During the day felt indoors by many, outdoors by few; at night some awakened; dishes, windows, doors disturbed; walls make cracking sound; sensation like heavy truck striking building; standing motor cars rocked noticeably MMI VII Everybody runs outdoors; damage negligible in buildings of good design and construction, slight to moderate in well-built structures, considerable in poorly built or badly designed structures; some chimneys broken; noticed by persons driving motor cars MMI VII Everybody runs outdoors; damage negligible in buildings of good design and construction, slight to moderate in well-built structures, considerable in poorly built or badly designed structures; some chimneys broken; noticed by persons driving motor cars MMI X Some well-built wooden structures destroyed; most masonry and frame structures destroyed with foundations; ground badly cracked; rails bent; landslides considerable from river banks and steep slopes; shifted sand and mud; water splashed over banks MMI X Some well-built wooden structures destroyed; most masonry and frame structures destroyed with foundations; ground badly cracked; rails bent; landslides considerable from river banks and steep slopes; shifted sand and mud; water splashed over banks

33. Basic Concepts of Seismology Seismic waves p-waves s-waves Love waves Rayleigh waves Body waves Body waves Surface waves Surface waves

34. Basic Concepts of Seismology Earthquake size Magnitude - quantitative measure of size of event Several types Local magnitude Body wave magnitude Surface wave magnitude All based on instrumental measurements All based on instrumental measurements

35. Basic Concepts of Seismology Earthquake size Seismic moment - measure of work done by eq. M o =  A D where  = shear modulus of rock A = rupture area D = average displacement over rupture area Units = F/L 2 x L 2 x L = F x L Work Energy

36. Basic Concepts of Seismology Earthquake size Moment magnitude M w = ------------ - 10.7 log M o 1.5 Moment magnitude Magnitude mbmb MLML MsMs M = M w Magnitude saturation Magnitude saturation

37. Earthquake Size

38. Shakes ground horizontally and vertically Wave damages structures Shakes ground horizontally and vertically Wave damages structures Similar to “S” wave Moves ground horizontally Similar to “S” wave Moves ground horizontally Like rolling ocean wave Shakes ground vertically and horizontally Like rolling ocean wave Shakes ground vertically and horizontally Arrives first Sometimes audible Arrives first Sometimes audible Seismic Waves

39. Strong motion seismograph Alcott Elementary, Redmond November 15, 11:10 am

40. Seismic Waves Triaxial accelerometers 3 components Horizontal motions are very important

41. So What? Deaths and injuries Economic loss

42. Hall of Fame (famous earthquakes) 1906 San Francisco

43. Hall of Fame (famous earthquakes) 1964 Niigata

44. Hall of Fame (famous earthquakes) 1964 Alaska

45. Hall of Fame (famous earthquakes) 1960 Chile

46. Hall of Fame (famous earthquakes) 1971 San Fernando

47. Hall of Fame (famous earthquakes) 1985 Mexico City

48. Hall of Fame (famous earthquakes) 1989 Loma Prieta

49. Hall of Fame (famous earthquakes) 1994 Northridge

50. Hall of Fame (famous earthquakes) 1995 Kobe

51. Hall of Fame (famous earthquakes) 1999 Chi Chi (Taiwan)