Scientists say there is a 63% probability of a damaging earthquake in the Bay Area in the next 30 years. Officials in quake-prone California recently took a step toward making the best of the Big One, when it does hit, by installing the densest array of accelerometers in any U.S. skyscraper to date. The 72 sensors, activated recently in the tallest tower in the U.S. built using performance-based seismic design, are expected to yield valuable data about the behavior of PBSD skyscrapers under quake loads.
"The key thing is the calibration and verification of performance-based design for high-rises," says Anthony Shakal, manager of the California Strong Motion Instrumentation Program of the California Geological Survey (CGS).