Evaluation of IM Efficiency for a Typical Highway Bridge Embankment

Estimation of the seismic performance of bridge embankments is an important application of advanced soil constitutive models to evaluate the potential damage to the bridge systems caused by earthquake induced liquefaction. The study presented in this paper revisits a typical highway bridge embankment using the newly implemented PM4Sand and PM4Silt constitutive models in OpenSees to study the efficiency of various Intensity Measures (IMs). This study follows the Pacific Earthquake Engineering Research Center (PEER)'s probabilistic framework for Performance Based Earthquake Engineering (PBEE) to evaluate the risk associated with earthquake shaking at this PEER testbed. Four different hazard levels of near-fault motions are considered and used in OpenSees simulations. Besides record-to-record uncertainty, spatial variability is also considered. Using OpenSees simulations, the relative efficiency of several IMs, including PGA, PGV, CAV5, and magnitude corrected PGA, is investigated to shed lights on reducing demand parameter uncertainty. Efficiency of IMs was examined, and the results show CAV5 is the most efficient IM in predicting liquefaction induced lateral displacements in the studied case.