【摘要】 为了研究盾构超近距下穿既有地铁车站的变形影响，基于郑州市苗二区间盾构隧道下穿2号线车站的实际工程，采用PLAXIS3D有限元分析软件进行数值模拟，模拟了新建盾构隧道施工的全过程，分析了下穿隧道施工中周围土体与既有线车站沉降、竖向位移的变化规律，并提出相应施工保证措施。结果表明：盾构下穿施工中主要造成既有线车站的竖向变形最大变形值为5.72 mm,越靠近新建隧道时变形量越大，但盾构隧道超近距下穿对既有线车站影响在可控范围之内，既有线车站的沉降均满足沉降要求。更多还原

【Abstract】 In order to study the deformation effect of shield tunneling underneath the existing subway station in ultra-close range, based on the actual project of shield tunneling underneath the station of Line 2 in Miaoer Section of Zhengzhou City, the numerical simulation was carried out by using PLAXIS 3D finite element analysis software.The whole construction process of the new shield tunnel was simulated, and the variation laws of the settlement and vertical displacement of the surrounding soil and the existing line station in the construction of the tunnel were analyzed, and the corresponding construction guarantee measures were put forward.The results show that the shield tunneling mainly causes the vertical deformation of the existing railway station, the maximum deformation value is 5.72 mm, and the closer the shield tunnel is to the new tunnel, the larger the deformation will be.However, the influence of shield tunnel undercrossing on the existing line station is within the controllable range, and the settlement of the existing line station meets the settlement requirements.更多还原