地震SV波入射角度对内河沉管隧道结构动力响应的影响分析  

Analysis of the Influence of Seismic SVWave Incident Angle on the Dynamic Response of Inland River Immersed Tunnel Structure

作　　者：何聪 陈忠章[1] 何必伍 贺文武 He Cong;Chen Zhongzhang;He Biwu;He Wenwu(Guangzhou Municipal Engineering Group Co.,Ltd.,Guangzhou 510060,China;College of Civil Engineering,Tongji University,Shanghai 200092,China;Guangdong Hengjian Pipe Gallery Investment Co.,Ltd.,Guangzhou 510520,China)

机构地区：[1]广州市市政集团有限公司,广东广州510060 [2]同济大学土木工程学院,上海200092 [3]广东恒建管廊投资有限公司,广东广州510520

出　　处：《市政技术》2024年第12期214-222,共9页Journal of Municipal Technology

摘　　要：为深入了解内河沉管隧道的地震效应,对沉管隧道在地震SV波斜入射作用下的动力响应进行了研究。基于时域有限元法和黏弹性人工边界,将地震动输入转化为等效节点荷载,实现了地震SV波斜入射,并通过算例验证了该方法的准确性。依托南昌红谷沉管隧道工程,建立了沉管隧道的二维有限元模型,研究了不同SV波入射角度对沉管隧道动力响应的影响。结果表明:SV波作用下沉管隧道顶部的地震响应大于底部,中隔墙的变形相较于边墙也更大,河床面会产生沉降变形;SV波斜入射使对称的沉管隧道结构产生了非对称的内力,随着SV波入射角度的增大,沉管隧道的竖向地震效应和河床面的沉降变形显著增大,水平地震效应有所减小,SV波入射角度的变化对水平地震效应的影响相较于竖向较为有限;沉管隧道的薄弱位置主要出现在拐角处及中隔墙与顶板、底板连接处,抗震设计中应重点关注该部位的结构承载力,并考虑SV波斜入射的影响。In order to deeply understand the seismic effect of inland river immersed tunnels,the dynamic response of immersed tunnels under oblique incidence of SV waves is studied.Based on the time-domain finite element method and viscous-elastic artificial boundary,the ground motion input is transformed into the equivalent node load to realize the oblique incidence of seismic SV waves.The accuracy of the method is verified by a numerical example.A 2D finite element model of immersed tunnel is established by the Honggu immersed tunnel project in Nanchang to study the impacts of different incident angles of SV wave on the dynamic response of immersed tunnels.The results indicate that the seismic response at the top of immersed tunnels is greater than that at the bottom under the effect of SV wave.The deformation of the middle partition wall is larger than that of the side wall.The riverbed surface will produce settlement deformation;The oblique incidence makes the symmetrical immersed structure produce asymmetric internal forces.With the increase of incident angle of SV wave,both the vertical seismic effect of immersed tunnel and the settlement deformation of riverbed surface increases significantly,while the horizontal seismic effect decreases.The one of SV wave incident angle changes on the horizontal seismic effect is relatively more limit than the vertical one;The weak position of immersed tunnels mainly occurs at the corners and the junction of the intermediate partition with floor and roof.The seismic design should focus on the structural bearing capacity of these parts as well as the influence of oblique incidence.

关 键 词：地震SV波 入射角度 斜入射 沉管隧道 动力响应 

分 类 号：U451[建筑科学—桥梁与隧道工程]