多点激励地震动空间效应参数敏感性分析  

Sensitivity analysis on seismic spatial variability parameters subjected to differential support motions

作　　者：钟剑[1,2] 王浩 朱小杰[2] Zhong Jian;Wang Hao;Zhu Xiaojie(College of Civil Engineering,Hefei University of Technology,Hefei 230009,China;Key Laboratory of Concrete and Pre-stressed Concrete Structures of Ministry of Education,Southeast University,Nanjing 210096,China)

机构地区：[1]合肥工业大学土木与水利工程学院,合肥230009 [2]东南大学混凝土及预应力混凝土结构教育部重点实验室,南京210096

出　　处：《东南大学学报（自然科学版）》2024年第6期1377-1385,共9页Journal of Southeast University：Natural Science Edition

基　　金：国家自然科学基金面上资助项目(52178135)。

摘　　要：为了探究地震动空间效应的3个主要因素——失相干效应、行波效应及局部场地效应对非线性时程的影响,基于相干函数,研究了剪切波速、场地频率、阻尼以及失相干系数对目标点地震波频谱特性的影响,并对主要的参数进行敏感性分析.结果表明:松软土层和中等土层以及松软土层和坚硬土层的频率响应函数在约1.5πHz出现峰值,在2πHz之后小于1;失相干效应参数从0.1 ms/m增加到1.0 ms/m时,地震动空间相关性逐渐减弱;距离从100 m变化到1000 m时,地震动空间相关性逐渐减小;距离与视波速的比值从0增加到1时,相位差呈现递增的趋势.松软土层对于低频有放大作用,对高频有滤波作用;随着失相干效应参数和距离的增加,地震动空间相关性减弱;距离与视波速的比值决定了相位差的大小.To explore the influences of the seismic spatial variability including incoherence effect,wave passage effect and local site effect on the nonlinear time-history,based on the coherency function,the effects of shear wave velocity,site frequency,damping,incoherence coefficient on the spectral characteristics of seismic wave at the target point were studied,and the sensitivity analysis of the main parameters was carried out.The results show that the peak of the frequency response function for soft-medium and soft-firm soil layers occurs at about 1.5πHz and is less than 1 after 2πHz;the spatial correlation of seismic motion decreases gradually as the incoherence effect parameter increases from 0.1 ms/m to 1.0 ms/m;the spatial correlation of seismic motion decreases gradually with distance from 100 m to 1000 m;the phase difference exhibits increasing trends as the ratio of distance to apparent wave velocity increases from 0 to 1.The soft soil layer can amplify the low frequency and filter the high frequency;with the increase of incoherence effect parameter and distance,the spatial correlation of seismic motion decreases;the ratio of distance to apparent wave velocity determines the magnitude of phase difference.

关 键 词：地震动空间效应 行波效应 局部场地效应 失相干效应 敏感性分析 

分 类 号：U442.2[建筑科学—桥梁与隧道工程]