EPS 20 Lecture Notes - Lecture 18: 1989 Loma Prieta Earthquake, West Valley College
26 Apr 2016
School
Department
Course
Professor
Document Summary
Completed in 1972, 49 stories, 850 feet high. In loma prieta earthquake the top swayed over 30 centimeters. The roof swayed more than expected because it was too exible. New buildings must be built to code, but old buildings do not need to be modi ed. Big changes to building codes: 1973: following 1964 alaska, 1967 caracas and 1971 san fernando earthquakes, 1997: following 1994 northridge and 1995 kobe earthquakes. Building codes are changed based on tenuation relationship (ground shaking in relation to distance from a speci c magnitude earthquake) In san francisco: 4 under construction, 10 approved, and 16 under review. We do not have much data on how skyscrapers fare in earthquakes. During an earthquake the soft story will collapse. In sf building owners are being required to retro t there soft story buildings. Homes can shift off their concrete foundation. Retro t: bolt the house down to the foundation.
