Baseline correction for digital strong-motion records by using the pre-event portion  

作　　者：Li Heng Yao Yunsheng Zheng Shuiming Cai Yongjian Lei Dongning 

机构地区：[1]Institute of Seismology, China Earthquake Administration, Wuhan 430071, China [2]Wuhan Institute of Earthquake Engineering, Wuhan 430071, China

出　　处：《Geodesy and Geodynamics》2011年第1期43-46,共4页大地测量与地球动力学（英文版）

基　　金：supported by the National Natural Science Foundation of China( 41004020);the Director Foundation of Institute of Seismology,CEA(IS200926044)

摘　　要：Baseline offset in digital strong-motion acceleration record and initial velocity can produce unrealistic results for ground velocity and displacement derived from the acceleration by integration. A new method is proposed for the baseline correction and initial velocity calculation. It is based on linear least-squares fitting of the pre-event portion of velocity derived from the uncorrected acceleration data. Compared with the conventional method,which is based on removing the mean values of the pre-event portions of the acceleration and velocity traces,this method has clearer physical meaning and better stability.Baseline offset in digital strong-motion acceleration record and initial velocity can produce unrealistic results for ground velocity and displacement derived from the acceleration by integration. A new method is proposed for the baseline correction and initial velocity calculation. It is based on linear least-squares fitting of the pre-event portion of velocity derived from the uncorrected acceleration data. Compared with the conventional method,which is based on removing the mean values of the pre-event portions of the acceleration and velocity traces,this method has clearer physical meaning and better stability.

关 键 词：baseline offset CORRECTION acceleration records initial velocity least-square fitting 

分 类 号：P315.7[天文地球—地震学] TN929.12[天文地球—固体地球物理学]