地震动多角度斜入射下无压隧洞地震响应分析  

Analysis of the Seismic Response of Unpressurized Tunnels Under Multi-Angle Oblique Ground Motions

作　　者：王昴 韦芳芳[1] 杨晶晶 王永泉 WANG Mao;WEI Fangfang;YANG Jingjing;WANG Yongquan(College of Civil and Transportation Engineering,Hohai University Nanjing,Nanjing 210098,China;Steel Structure Construction of China Railway No.4 Civil Engineering Group Co.Ltd.,Hefei 230031,China;School of Engineering and Architecture,Nanjing Institute of Technology,Nanjing 211167,China)

机构地区：[1]河海大学土木与交通学院,南京210098 [2]中铁四局集团钢结构建筑有限公司,合肥230031 [3]南京工程学院建筑工程学院,南京211167

出　　处：《河南科学》2024年第4期567-577,共11页Henan Science

基　　金：国家重点研发计划(2020YFC1511901)。

摘　　要：为研究地震动多角度倾斜入射下无压水工隧洞动力响应特征和规律,采用黏弹性人工边界模拟无限地基的辐射阻尼和弹性恢复力,将地震动转化为人工边界节点上的节点力,以实现地震动的非一致性输入.通过ABAQUS建立水工隧洞模型,将不同入射角度P波、SV波输入模型中,分析隧洞衬砌结构的环向应力、径向应力随地震动入射角度、缩放系数、隧洞埋深、洞身直径以及衬砌厚度的变化.结果表明,同一地震动入射倾角下,随着入射方位角的增大,环向应力逐渐减小,径向应力逐渐增大.地震动峰值加速度(Peak Ground Acceleration,PGA)显著影响衬砌结构应力,并且应力数值随PGA的变化呈整数倍增大;随着隧洞埋深由浅埋向中埋、深埋发展,隧洞应力先逐渐增大后减小,后趋于稳定;随着洞身直径的增大,环向、径向应力分别受P波、SV波影响,洞身直径每增加2m,环向、径向应力分别增大约16%、21%;衬砌厚度每增加0.1m,径向应力降低10%左右,当地震波垂直隧洞轴线入射时,衬砌厚度超过1.0m后,对应力的影响效果减弱.To study the characteristics and regularity of the dynamic response of unpressurized hydraulic tunnels under different angles of incidence of ground vibration,the radiation damping and elastic restoring force of infinite foundations are simulated using a viscoelastic artificial boundary,which transforms the ground vibration into nodal forces at the nodes of the artificial boundary for the inconsistent input of ground vibration.The hydraulic tunnel model is properly established by ABAQUS,and the P waves and SV waves with different incident angles are inputted into the mould to analyze the changes of circumferential stress,radial stress with the incident angle of vibration,the scaling factor,the depth of the mine,the diameter of the tunnel and the thickness of the tunnel lining.The study indicates that,for a fixed ground vibration incident inclination,the circular stress decreases and the radial stress rises as the incident azimuthal angle increases,For instance.The structural stresses in the lining are significantly affected by Peak Ground Acceleration(PGA),and the stress values increase proportionally with PGA.As the depth of the tunnel progresses from shallow to medium and deep,the stresses in the tunnel first increase gradually,then decrease and then tend to stabilize.The circular and radial stresses are primarily influenced by the P-wave and SV-wave as the hole diameter increases.For each 2 m increase in cave diameter,there is an average rise of approximately 16% and 21% in circumferential and radial stresses,respectively.The radial stress decreases by about 10% for every 0.1 m increase in lining thickness,and when the seismic waves are incident perpendicular to the tunnel axis and the lining thickness is more than 1.0 m,the influence on the stresses is weakened.

关 键 词：水工隧洞 黏弹性边界 地震动倾斜入射 隧洞衬砌 地震响应 

分 类 号：TV39[水利工程—水工结构工程]