双基坑开挖对邻近隧道结构变形影响分析  

Analysis on the Influence of Adjacent Double Foundation Pit Excavation on Tunnel Deformations

作　　者：张治国[1] 费思异 邢李[1] 

机构地区：[1]上海理工大学环境与建筑学院,上海200093

出　　处：《上海理工大学学报》2017年第2期176-181,共6页Journal of University of Shanghai For Science and Technology

基　　金：上海市自然科学基金资助项目(15ZR1429400)

摘　　要：通过建立三维有限元数值模型,分析了双基坑开挖不同施工阶段对已有隧道变形的影响.结果表明:双基坑与邻近隧道平行布置时,隧道会发生较大变形,其水平最大位移比垂直布置时的大10%,且后开挖基坑造成的隧道位移较先开挖基坑变形大7%左右;双基坑与隧道垂直布置时,远隧道基坑开挖对隧道影响极小,隧道变形主要由近隧道基坑开挖决定.针对上述水平布置和垂直布置工况均发现,隧道一侧双基坑开挖施工对隧道的水平位移影响较大,竖向位移约为水平位移的1/10.隧道本身在竖直方向变形为上下向中心挤压,隧道在水平方向上有指向基坑的侧移,同时隧道本身的变形为中心向两侧拉伸,且在开挖基坑中心位置对应处隧道的位移与变形最为明显.The deformations of an existing tunnel induced by the adjacent double foundation pit excavation at different construction stages were analyzed by establishing a 3Dfinite element model.The results show that the deformation of the tunnel is great when the double foundation pit is parallel to the adjacent tunnel,and the maximum horizontal displacement is approximately 10%larger than the displacement when the double foundation pit is perpendicular to the tunnel.The later pit excavated later will cause larger deformation of the tunnel than that excavated earlier by about 7%.The excavation of the pit far from the tunnel has few influences on the deformation of the tunnel when the double foundation pit is perpendicular to the adjacent tunnel.The tunnel deformation is mainly determined by the excavation of the foundation pit near the tunnel.No matter which kind of layout,it is found that the excavation of double foundation pit on one side of the tunnel causes superior influence on the horizontal displacement and little influence on the vertical direction of the tunnel.The vertical displacement is about 1/10 of the horizontal displacement.The vertical deformation of the tunnel is an extrusion from two sides to the center of the tunnel.The horizontal displacement of the tunnel is pointed to the side of pit and the horizontal deformation ofthe tunnel is a tension from center to the edge sides of the tunnel.The most obvious displacement and deformation of the tunnel appear at the place corresponding to the center of the excavated pit.

关 键 词：双基坑开挖 隧道 水平变形 竖向变形 

分 类 号：TU430[建筑科学—岩土工程]