浅埋偏压连拱隧道地震响应规律研究  

Study on seismic response law of shallow-buried bias double-arch tunnel

作　　者：杨慧[1,2] 刘潺 江学良[1,2] 石洪涛 孙广臣[1,2] YANG Hui;LIU Chan;JIANG Xueliang;SHI Hongtao;SUN Guangchen(School of Civil Engineering,Central South University of Forestry and Technology,Changsha 410004,China;Institute of Geotechnical Engineering,Central South University of Forestry and Technology,Changsha 410004,China;Dahan Urban Construction Co.,Ltd.Changsha 410200,China)

机构地区：[1]中南林业科技大学土木工程学院,湖南长沙410004 [2]中南林业科技大学岩土工程研究所,湖南长沙410004 [3]大汉城镇建设有限公司,湖南长沙410200

出　　处：《自然灾害学报》2020年第4期161-172,共12页Journal of Natural Disasters

基　　金：国家自然科学基金(51204125,51404309);湖南省自然科学基金(2018JJ3882);湖南省应急管理科技项目(31971727)。

摘　　要：基于相似理论,设计并制作了几何相似比为1:20的浅埋偏压连拱隧道物理模型,完成了振动台试验并测得衬砌的应变响应与加速度响应。在试验基础上,通过MIDAS GTS NX有限元软件建立数值模型,验证了数值模型的合理性与可靠性,研究了浅埋偏压连拱隧道的地震响应规律。结果表明:(1)上覆土层厚度、偏压、衬砌与临空面的距离对浅埋偏压连拱隧道加速度响应的影响较大。(2)浅埋偏压连拱隧道中墙上的应变由于截面几何形式突变与集中力的原因,相对其余测点较大。(3)大小主应变与加速度放大系数趋势线的整体形状不随激振强度的增加而改变。(4)偏压与覆土厚度对连拱隧道位移的影响较小。(5)浅埋偏压连拱隧道中隔墙的应变、轴力、剪力和弯矩相对其他部位均较大,在进行浅埋偏压连拱隧道的抗震设计时,应给与重视。Based on the similarity theory,a physical model of double-arch tunnel with geometric similarity ratio of 1:20 is designed and made.The strain response and acceleration response of lining were measured by shaking table test.On the basis of test,the numerical model was established by MIDAS GTS NX finite element software to verify the rationality and reliability of the numerical model.The seismic response of shallow-buried bias double-arch tunnel is studied.The results show that:(1)The acceleration response of shallow-buried bias double-arch tunnel is greatly affected by the thickness of overlying soil layer,the bias pressure and the distance between lining and the air surface.(2)Strain on the middle-wall of shallow-buried bias double-arch tunnel is larger than that at other measuring points due to the sudden change of the section geometry and concentrated force.(3)The overall shape of the trend line of the major strain and acceleration amplification factor does not change with the increase of excitation intensity.(4)The displacement of double-arch tunnel is less affected by the bias and the thickness of overburden.(5)The strain,axial force,shear force and moment of the middle-wall in shallow-buried bias double-arch tunnel are relatively large compared with other parts.Attention should be paid to the seismic design of shallow-buried bias double-arch tunnel.

关 键 词：地震工程 地震响应规律 振动台试验 数值模拟 浅埋偏压连拱隧道 

分 类 号：U45[建筑科学—桥梁与隧道工程] X9[交通运输工程—道路与铁道工程]