NGA-West2地震动预测模型对速度脉冲型地震动各分量的适用性  

Applicability of the Next Generation Attenuation-West2 ground-motion models to the components of near-fault velocity pulse-like ground motions

作　　者：赵晓芬 温增平[1] 谢俊举[1] 解全才[2] Zhao Xiaofen;Wen Zengping;Xie Junju;Xie Quancai(Institute of Geophysics,China Earthquake Administration,Beijing 100081,China;Institute of Engineering Mechanics,China Earthquake Administration,Harbin 150080,China)

机构地区：[1]中国地震局地球物理研究所,中国北京100081 [2]中国地震局工程力学研究所,中国哈尔滨150080

出　　处：《地震学报》2023年第2期356-372,共17页Acta Seismologica Sinica

基　　金：中国地震局地球物理研究所基本业务费(DQJB21K44);国家重点研发项目(2020YFA0710603)共同资助。

摘　　要：鉴于传统的地震动预测模型未考虑速度脉冲的影响,可能会低估近断层区域的地震风险,而新一代NGA-West2地震动预测模型对速度脉冲型地震动的适用性有待研究。首先,收集了2013年以来的近断层地震动记录,在充分考虑脉冲方向的不确定性条件下,基于小波方法定量地识别出速度脉冲记录,形成了最新的速度脉冲记录数据库;然后,利用小波提取出速度脉冲记录中的长周期脉冲信号,基于偏差参数分析方法,定量地研究NGA-West2地震动预测模型分别对速度脉冲原始记录和提取长周期脉冲后的残余记录的适用性。研究结果显示,NGA-West2中的四个地震动预测模型均会低估近断层速度脉冲记录,特别是在脉冲周期附近的周期段内速度脉冲观测值远远大于这四个预测模型的预测值,但残余记录观测值与NGA-West2中四个地震动预测模型的预测值较吻合。值得注意的是,CB2014地震动预测模型能更好地预测残余记录。The traditional ground-motion models(GMMs)do not account for pulse effects and may therefore fail to estimate seismic hazards and risk at near-fault sites,where pulse-like ground motions are expected.Thus,the applicability of the NGA-West2 GMMs to the near-fault velocity pulse-like ground motions need to be tested.The near-fault strong ground motions are quantitatively identified from recent earthquakes since 2013 by using wavelet method and tak- ing the uncertainty of pulse orientation into consideration so as to form a new pulse database. Based on the new pulse database,long-period pulses are extracted from the original pulse records by using wavelet method. Based on a quantitative analysis of the epsilon parameter,we quantitatively test the applicability of the NGA-West2 ground-motion model to the near-fault velocity pulse-like ground motions. The results show that the four NGA-West2 models are more suitable for describing the residual recordings in the studied period,but underestimate the original pulse-like ground motions especially around the pulse period. We noted that,among the four NGA-West2 models,the applicability of the CB2018 to the residual ground motions is the best. This study provides an excellent opportunity to quantitatively evaluate the NGA-West2 GMMs and to update these models in the near future,and also provides a basis for incorpora-ting pulse effects into near-fault probabilistic seismic hazard analysis and seismic design.

关 键 词：地震动预测模型 速度脉冲记录 残余记录 适用性 

分 类 号：P315.9[天文地球—地震学]