基于宽频带混合法的跨断层地震动模拟研究  

Research on simulation of cross-fault ground motion based on broadband hybrid method

作　　者：陈何煜 陈力波[1] 栗怀广[2] 金洋 谷音[1] CHEN Heyu;CHEN Libo;LI Huaiguang;JIN Yang;GU Yin(College of Civil Engineering,Fuzhou University,Fuzhou 350108,China;College of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China)

机构地区：[1]福州大学土木工程学院,福建福州350108 [2]西南交通大学土木工程学院,四川成都610031

出　　处：《地震工程与工程振动》2024年第5期125-138,共14页Earthquake Engineering and Engineering Dynamics

基　　金：国家自然科学基金项目(52278159);福建省自然科学基金面上项目(2020J01478);福州大学可持续与创新桥梁福建省高校工程研究中心开放课题(SIBERC2022005);四川省交通运输科技项目(2018-ZL-01)。

摘　　要：跨断层区域地震动(跨断层工程结构所在极近断层区域的地震动,以下简称跨断层地震动)与近场地震动在空间上的分布规律存在显著差异,而跨断层地震动记录匮乏导致跨断层结构抗震研究难以开展。文中简要介绍了宽频带混合法模拟地震动的基本理论,并以则木河断层为工程背景进行跨断层地震动的模拟,系统研究了跨断层地震动的分布规律。结果表明,模拟的跨断层地震动符合断层滑动模式,并且存在显著的方向性效应、上盘效应和滑冲效应,总体上模拟的跨断层地震动强度符合一定的衰减规律,但受断层破裂的影响会导致不规律甚至反规律。同时,实际地表破裂位置与断层破裂大滑移区对跨断层地震动分布规律会造成较大的影响。通过宽频带混合法人工模拟的跨断层地震动时间序列能解决跨断层地震动实测记录不足的问题,为跨断层结构抗震研究提供有力支撑。There is a significant difference between the spatial distribution of ground motion along cross-fault regional areas(Ground motion in the area of the extreme proximity to the fault where the cross-fault engineering structures are located,referred to as cross-fault ground motion)and near-site ground motion.The lack of records on cross-fault ground motion poses challenges to studying the seismic resistance of cross-fault structures.This paper aims to outline the basic theory of the broadband hybrid method for simulating ground motion,and examines the distribution pattern of cross-fault ground motion using the Zemu River fault as a case study.The results indicate that the simulated cross-fault ground motion aligns with the fault sliding mode,displaying significant directional,up-disk effect,and slip-impact effect.Generally,the intensity of the simulated cross-fault ground motion follows a certain attenuation law.However,it is influenced by fault rupture,which can result in irregularities or even a counter-law phenomenon.Furthermore,the actual location of surface rupture and the zone of large slip along the fault have a substantial impact on the distribution pattern of cross-fault ground motion.By employing the broadband hybrid method,artificial cross-fault ground vibration time series can be generated to address the lack of recorded cross-fault ground motion.This methodology provides substantial support for research on the seismic resistance of cross-fault structures.

关 键 词：跨断层地震动 左旋逆走滑断层 地震动分布规律 宽频带混合法 断层破裂模型 

分 类 号：TU435[建筑科学—岩土工程]