表征近断层地震动永久位移的基线校正方法  

A baseline correction method for characterizing permanent displacement of near-fault ground motion

作　　者：陈科旭 俞瑞芳[1] 徐建荣 CHEN Ke‑xu;YU Rui‑fang;XU Jian‑rong(Institute of Geophysics,China Earthquake Administration,Beijing 100081,China;Huadong Engineering Co.,Ltd.,Power China,Hangzhou 311122,China)

机构地区：[1]中国地震局地球物理研究所,北京100081 [2]中国电建集团华东勘测设计研究院有限公司,浙江杭州311122

出　　处：《振动工程学报》2024年第12期2012-2020,共9页Journal of Vibration Engineering

基　　金：国家自然科学基金资助项目(51878627);中国电建华东院资助科研项目(KY2018-ZD-02)。

摘　　要：在对近断层原始地震加速度记录的处理中,如何保留真实的地面永久位移信息,是目前地震加速度记录基线校正中需要解决的关键问题。本文在对现有近断层地震加速度基线校正方法的有效性及适用范围分析和讨论的基础上,引入平滑斜坡位移函数模型,建立了能够合理表征近断层地震动永久位移的一种基线校正方法,并通过典型近断层加速度记录的基线处理对该方法进行了校验。结果表明,本文建立的方法改善了位移函数模型与位移时程之间的拟合精度,能减少主观参数选择对基线校正结果的影响,且校正后的地面永久位移与GPS同震位移吻合度较高。本文建立的地震动基线校正方法不仅能够自动处理近断层地震动的基线漂移,且能合理表征由于滑冲效应而产生的地面永久位移。In the processing of near-fault original seismic acceleration records,how to retain the real ground permanent displacement information is a key problem to be solved in the baseline correction of seismic acceleration records.Based on the analysis and discussion of the validity and applicable scope of existing near-fault seismic acceleration baseline correction methods,this study introduces a smooth slope displacement function model and establishes a new baseline correction method that can reasonably characterize the permanent displacement of near-fault ground motions,and the new baseline correction method is verified by analyzing the baseline correction results of typical near-fault acceleration records.The results show that the new method established in this study improves the fitting accuracy between the displacement function model and displacement time history,reduces the influence of the selection of subjective parameters on the baseline correction results,and the corrected ground permanent displacement is in good agreement with the GPS co-seismic displacement.The ground motion baseline correction method established in this paper can not only automatically deal with the baseline drift of near-fault ground motion,but also reasonably characterize the permanent ground displacement caused by fling-step effect.

关 键 词：近断层地震动 基线校正 地面永久位移 GPS同震位移 

分 类 号：P315.91[天文地球—地震学]