Near-Fault and Far-Field Strong Ground-Motion Simulation for Earthquake Engineering Applications Using the Specific Barrier Model

Abstract

Codes for aseismic design may require use of recorded ground motions as input in dynamic analysis. When records are not available, motions must be simulated. The specific barrier model (SBM) is particularly useful in this context because (1) it provides the most complete, yet parsimonious, self-consistent description of the earthquake faulting processes that are responsible for the generation of high-frequency radiation; (2) it has been calibrated to earthquakes of three different tectonic regions; and (3) its key parameter, the barrier interval, is related to the duration of the near-fault pulses (NFP), the most damaging feature of near-fault motions. We carry out “blind” (i.e., using the minimum amount of a priori source information) simulations of strong motions of well-recorded earthquakes of magnitudes between 6.2–7.6. We assess the quality of fit of the simulated time histories to the recorded motions and show that the simulations exhibit close to zero bias over frequencies of 0.1–20 Hz for the data set used. This exercise illustrates that the method will provide earthquake motions that can be used with confidence in aseismic design.