The amateur videos emerging from the magnitude 7.1 earthquake that devastated Mexico City on Tuesday are grim. In that country’s 1985 earthquake, buildings that were five to 20 stories tall suffered major damage, Jones said, while shorter buildings generally performed better. Why brittle concrete buildings collapseMiyamoto said the types of buildings that have collapsed in Mexico City are what structural engineers would expect: brick structures as well as brittle concrete buildings, especially those with weak first floors. Two concrete buildings at the San Fernando Veterans Administration Hospital crumbled in the 1971 Sylmar earthquake. It was built in the 1960s, before the adoption of modern seismic standards for concrete buildings.

Source: Los Angeles Times September 20, 2017 19:51 UTC