PEER Reports

The magnitude 6.0 South Napa Earthquake of August 24, 2014, took the lives of two people, injured 300 others, and caused moderate to severe damage to more than 2,000 structures. It is one of the first damaging earthquakes to strike a major metropolitan area in the State of California in over two decades. During that time period, California’s population has grown by over 25%, the state’s economy has tripled, and a great many of the state’s new residents and businesses have never experienced a major earthquake. It is almost guaranteed that there will be a major damaging earthquake somewhere...

Construction or detailed evaluation of transportation infrastructure requires site-specific ground motions for input into nonlinear structural models. These site-specific ground motions are generally selected based on the magnitude, distance, and site condition of the recorded ground motion. A preliminary study performed by Slate Geotechnical Consultants found that duration and spectral acceleration are negatively correlated for large-magnitude earthquakes recorded on soft-soil sites (Vs30<360 m/s). This means that if the target spectral acceleration is above average, then the average...

The UC San Diego Large High-Performance Outdoor Shake Table (LHPOST), which was commissioned on October 1, 2004 as a shared-use experimental facility of the National Science Foundation (NSF) Network for Earthquake Engineering Simulation (NEES) program, was upgraded from its original one degree-of-freedom (LHPOST) to a six degree-of-freedom configuration (LHPOST6) between October 2019 and April 2022. The LHPOST6 is a shared-use experimental facility of the NSF Natural Hazard Engineering Research Infrastructure (NHERI) program. A mechanics-based numerical model of the LHPOST6 able to capture...