Building owners commonly believe good performance of their building during the 1989 Loma Prieta earthquake validates a building as being safe to withstand a major earthquake. However, the Loma Prieta earthquake registered a magnitude 6.9 with an epicenter located approximately 60 miles from San Francisco. For comparison, the Great Earthquake of 1906 registered a magnitude of Approximately 7.8 with an epicenter estimated to be approximately 2 miles from San Francisco. The estimated intensity of shaking in the 1906 earthquake was approximately 10 times that of the 1989 earthquake. A major earthquake occurring near San Francisco along the San Andreas, Hayward, or other known or unknown local faults, could cause significant damage in buildings that may have suffered little or no damage during the 1989 Loma Prieta Earthquake. Please keep this in mind when considering building safety and your retrofit needs.
Common Misconception: My Building Survived 1989 Earthquake So I Don’t Need A Retrofit
Posted by admin on January 24, 2014
http://enginious-structures.com/softstoryblog/?p=415