暗挖施工通道对邻近地铁区间的影响分析

Analysis on Operation Tunnel Responses Inducedby Dark-excavated Construction Passage

文章以重庆市某在建暗挖地铁车站为例,采用有限元分析软件Midas-NX开展数值分析,探讨了在建地铁暗挖施工通道开挖工况对运营区间的影响规律,分析了围岩变形特征和运营区间的变形情况。研究结果表明:施工通道开挖时,既有区间隧道上方岩土沉降最大。既有区间最大水平变形发生在腰部位置,最大竖向变形发生在拱顶、拱底位置。采用合理的暗挖支护措施能有效减小对既有轨道交通的影响。

Taking an undercutting subway station under construction in Chongqing as an example,this paper uses the finite element analysis software Midas-NX to carry out numerical analysis,discusses the influence law of the excavation condition of the undercutting construction channel of the subway under construction on the operating section,and analyzes the deformation characteristics of the surrounding rocks and the deformation situation of the operating section.The results show that when the construction channel is excavated,the settlement of rock and soil above the existing interval tunnel is the largest.The maximum horizontal deformation of the existing section occurs at the waist position,and the maximum vertical deformation occurs at the top and bottom of the arch.The use of reasonable undercutting support measures can effectively reduce the influence on existing rail transit.