Near-fault ground motion reconstruction method based on observed data and equivalent pulse model

Abstract:

Near-fault ground motions are critical for assessing seismic damage. However, recorded near-fault ground motion during an earthquake is often limited. To address the challenge of evaluating seismic damage to engineering structures in near-fault regions, particularly for supplementing ground motion at sites without observing stations in near-fault regions, this study proposed a near-fault ground motion reconstruction method based on observed data and an equivalent pulse model. The method initially generated ground motion at sites without observing stations in near-fault regions by interpolating response spectra from observed near-fault ground motion. Subsequently, it employed an empirical equivalent pulse model to recover velocity pulses and permanent displacements of ground motion. By taking the Chi-Chi earthquake in Taiwan, China as an example, examples of ground motion reconstruction at two typical locations in the near-fault region were provided. By comparing them with the observed ground motion data, the effectiveness and rationality of the method were validated. The results demonstrate that the method effectively reconstructs ground motions with near-fault pulse-like characteristics and ground motion at sites without observed data in near-fault regions. This offers a practical approach to meet the need for ground motion in near-fault regions where observed data are lacking.