Prediction of near-fault strong ground motion field
近断层强地震动场预测

Taking 1997 Jiashi earthquake (Mw 6.1), Xinjiang, China as an example, a method for predicting near-fault strong ground motion field was introduced in detail. Firstly, the earthquake source model of the earthquake was established based on the finite fault source modeling method. Secondly, acceleration time histories of the three stations above huge thick sediment strata with main-shock records during the earthquake were simulated based on the stochastic method of ground motions with the dynamic corner frequency; and the results were validated by comparison of response and Fourier spectra between simulated and recorded acceleration time histories. Finally, the acceleration field of the earthquake was drawn based on PGA of the predicted acceleration time histories of 77 near-fault nodes. The results show that simulated acceleration time histories are feasible and practical when frequency is more than 0.5 Hz, and the acceleration field shows very obvious hanging wall effects. The maximum PGA area on ground surface corresponds to the maximum asperity area, and this means that buildings and other engineering structures on ground surface corresponding to the maximum asperity area on the earthquake fault may suffer severe damage.