地下隧道对地震动加速度峰值及反应谱的影响  

Influence of underground tunnel on peak ground acceleration and response spectrum

作　　者：蔡金豆 兰景岩 史庆旗[1] CAI Jindou;LAN Jingyan;SHI Qingqi(College of Civil Engineering and Architecture,Guilin University of Technology,Guilin 541004,China;Guangxi Key Laboratory of Geomechanics and Geotechnical Engineering,Guilin University of Technology,Guilin 541004,China)

机构地区：[1]桂林理工大学土木与建筑工程学院,广西桂林541004 [2]桂林理工大学广西岩土力学与工程重点实验室,广西桂林541004

出　　处：《自然灾害学报》2022年第3期141-148,共8页Journal of Natural Disasters

基　　金：国家自然科学基金项目(52168067);广西高等学校千名中青年骨干教师培育计划(2020);广西岩土力学与工程重点实验室开放基金(桂科能19-Y-21-4)。

摘　　要：基于剑桥大学工程系所完成的含隧道密实砂场地动力离心模型试验基础数据,利用模型内部设置微型加速度传感器,由弱至强逐级加载四组伪谐波作为基底输入,模拟并获取了在80 g重力场环境下隧道列及自由场列在不同深度处的动力反应和加速度记录,通过对比隧道列及自由场列相关地震动参数的差异,表明由于隧道的存在,峰值加速度放大系数从基底到地表都呈现出先衰减后放大的趋势,自由场列地表处的峰值加速度放大系数处于1.042~1.072之间,而隧道列地表处放大系数处于1.009~1.024之间;加速度反应谱峰值方面,地震波输入越强烈,其峰值相对应周期朝着短周期方向移动;对比两列地震动加速度反应谱峰值随深度变化曲线,发现自由场列从基底到地表呈现逐渐增大的趋势,而隧道列呈现先减小后增大的趋势。Based on the basic data of the dynamic centrifugal model test on the site with tunnel dense sand complet-ed by the Engineering Department of Cambridge University,using the micro acceleration sensor set in the model,four groups of pseudo harmonics are loaded step by step from weak to strong as the base input,the dynamic re-sponse and acceleration records of the tunnel column and the free field column at different depths under the environ-ment of 80 g gravity field are simulated and obtained.By comparing the differences of relevant ground motion pa-rameters between tunnel column and free field column,it shows that due to the existence of tunnel,the amplifica-tion coefficient of peak acceleration first attenuates and then amplifies from the base to the surface.The amplifica-tion coefficient of peak acceleration at the surface of free field column is between 1.042~1.072,while the amplifi-cation coefficient at the surface of tunnel column is between 1.009~1.024;In terms of the peak value of accelera-tion response spectrum,the stronger the seismic wave input,the corresponding period of the peak value of re-sponse spectrum moves towards the short period direction;Comparing the variation curves of the peak value of ac-celeration response spectrum with depth between the two columns,it is found that the free field column gradually increases from the base to the surface,while the tunnel column first decreases and then increases.

关 键 词：动力离心模型试验 场地效应 地下隧道 加速度放大系数 地震动反应谱 

分 类 号：TU4[建筑科学—土工工程]