防灾减灾工程学报2025，Vol.45Issue(5)：1024-1031,8.DOI:10.13409/j.cnki.jdpme.20250324001
基于竖向台阵的土体小应变阻尼比随深度变化规律研究
Research on Variation of Soil Small-strain Damping Ratio with Depth Based on Vertical Arrays
摘要
Abstract
Currently,the small-strain damping of soil used in seismic site response analysis is general-ly determined based on laboratory tests.However,since laboratory tests can only represent material damping of soil,they cannot reflect the scattering effects caused by spatial variability of the site dur-ing seismic wave propagation.Therefore,directly using the small-strain damping obtained from labo-ratory tests often leads to a significant overestimation of the predicted site amplification.To address this issue,this study selected four vertical seismic arrays from the United States and Europe.First,the in-situ shear wave velocity structures of these sites were extracted from the seismic data using the seismic interferometry method.Then,the in-situ small-strain damping ratio structures were inverted using the simulated annealing algorithm,and the variation of the small-strain damping ratio of the soil with depth was discussed.Finally,the performance of the uniform damping assumption and the non-uniform damping assumption in reproducing and predicting seismic site response was compared.The results showed that the in-situ soil dynamic parameters inverted using seismic interferometry and the simulated annealing algorithm could well reproduce and predict the seismic site response under small-strain conditions.Meanwhile,the in-situ small-strain damping ratio profile did not exhibit a clear variation pattern with depth.Moreover,in most cases,whether the uniform damping assump-tion was adopted had almost no effect on the simulated values of surface acceleration response spec-tra.Therefore,the uniform damping assumption could be directly adopted in seismic site response analysis under normal circumstances,without the need to consider the variation of damping ratio with depth.关键词
场地地震反应/小应变阻尼/剪切波速结构/竖向台阵/地震干涉测量法Key words
seismic site response/small-strain damping/shear wave velocity structure/vertical array/seismic interferometry分类
建筑与水利引用本文复制引用
陈苏,龙增洋,王苏阳,姜伟平,李小军..基于竖向台阵的土体小应变阻尼比随深度变化规律研究[J].防灾减灾工程学报,2025,45(5):1024-1031,8.基金项目
国家重点研发项目(2023YFB2390400)、国家自然科学基金项目(52192675)资助 （2023YFB2390400）
