Determination and application of path duration of seismic ground motions based on the K-NET data in Sagami Bay,Japan  

作　　者：Shiyang Chen Xiaojun Li Lei Fu Su Chen 

机构地区：[1]Institute of Geophysics,China Earthquake Administration,Beijing 100081,China [2]Beijing University of Technology,Beijing 100124,China

出　　处：《Earthquake Science》2022年第4期263-279,共17页地震学报（英文版）

基　　金：This study is supported by the National Natural Science Foundation of China(No.U1839202).

摘　　要：Duration models are one of the important parameters in ground-motion simulations.This model varies in different study areas,and plays a critical role in nonlinear structural response analysis.Currently,available empirical models are being globally used in ground-motion simulations,with limited research focusing on path duration in specific regions.In this study,we collected 6,486 sets of three-component strong-motion records from 29 K-NET stations in the Sagami Bay,Japan,and its surrounding areas between January 2000 to October 2018.We extracted the effective duration of 386 pieces of ground-motion records by manually picking up the S-wave arrival time and calculating the significant duration.We then obtained the path duration model of the study area based on the empirical equation of dynamic corner frequency and source duration of Boore(2009).Compared with the results of the available empirical models,the Fourier spectrum of the simulated ground motion from our effective duration model showed higher accuracy in the long-term range,with less fitting residuals.This path duration model was then applied to simulate two earthquakes of M_(W)5.4 and M_(W)6.2,respectively,in the region using the stochastic finite-fault method with a set of reliable source,path,and site parameters determined for the study area.The simulation results of most stations fit well with observation records in the 0-30 Hz frequency band.For the M_(W)5.4 earthquake,the simulated ground motions at KNG005/KNG010/SZO008 stations were relatively weak in the mid to high frequency band(1-30 Hz)because the quality factor and geometric diffusion model used in the simulation were the averages of the entire Sagami Bay region,causing a bias in the results of a few stations owing to local crustal velocity anomalies and topographic effects.For the M_(W)6.2 earthquake,the simulated ground motions were relatively weak at all SZO and TKY stations,mainly because of the close distance from these stations to the epicenter and the complex seismic-wave propagation pa

关 键 词：Sagami Bay path duration effective duration stochastic finite-fault method 

分 类 号：P315[天文地球—地震学]