地震波对干砂场地土层加速度放大系数影响分析  

Influence of seismic waves on acceleration amplification factor of soil in a dry sand site

作　　者：刘春辉 翁建燎 孔璟常 张梦子 卢龙玉 王永志[2] LIU Chunhui;WENG Jianliao;KONG Jingchang;ZHANG Mengzi;LU Longyu;WANG Yongzhi(College of Civil Engineering,Yantai University,Yantai 264005,Shandong,China;Key Laboratory of Earthquake Engineering and Engineering Vibration,Institute of Engineering Mechanics,CEA,Harbin 150080,Heilongjiang,China)

机构地区：[1]烟台大学土木工程学院,山东烟台264005 [2]中国地震局工程力学研究所地震工程与工程振动重点实验室,黑龙江哈尔滨150080

出　　处：《地震工程学报》2022年第6期1287-1293,共7页China Earthquake Engineering Journal

基　　金：国家自然科学基金资助项目(51908484,51808479);山东省自然科学基金资助项目(ZR201807080133,ZR201807080139);中国地震局工程力学研究所基本科研业务专项资助项目(2019D09)。

摘　　要：为研究土体加速度在向上传递时,不同地震动对其峰值的影响,设计制作了干砂场地离心振动台试验,通过对比得出加速度放大系数沿深度变化的规律。结果表明:地震动加速度幅值越大,其沿深度变化的放大系数越小;在波的幅值增大时,其放大系数存在一定的衰减率,且衰减率随着幅值的增大而减小;在相同幅值不同频谱特性地震动作用下,等幅正弦波的加速度放大系数最大,LEAP波其次,El-Centro波最小。土体加速度放大系数及其衰减率的分析有助于研究场地的动力响应变化规律,对抗震设计具有一定参考价值。A centrifugal shaking table test on a dry sand site was designed and conducted to study the influence of different seismic waves on the peak value of soil acceleration during its upward transmission,and the variation law of acceleration amplification factor along the depth was obtained by comparison.Results show that the amplification factor of ground motion acceleration along the depth decreases with the increase in amplitude.Moreover,a certain attenuation rate of the amplification factor is observed when the amplitude of the wave increases,and the attenuation rate decreases with the increase in the amplitude.Under the action of seismic waves with the same amplitude and different frequency spectra,the acceleration amplification factor of the invariable amplitude sine wave is the largest,followed by the LEAP wave,and that of the El-Centro wave is the smallest.The analysis of the soil acceleration amplification factor and its attenuation rate is helpful in studying the dynamic response of similar sites,which also has a certain reference value for seismic design.

关 键 词：离心机振动台试验 加速度 放大系数 衰减率 干砂场地 

分 类 号：TU43[建筑科学—岩土工程]