【摘要】 采用三维有限元模拟盾构推进的过程，是研究盾构施工中土层移动的最有效的手段。采用三维弹塑性有限元，在真实模拟施工情况的基础上，研究了新隧道从老隧道下面垂直穿过时，对老隧道的变形影响情况。研究表明，推进力和稳定比N是影响老隧道变形的主要因素。更多还原

【Abstract】  Using the 3D elasto－plastic FEM to simulate the shield advance is the most effective method for research of the ground movement during the construction of the tunnel． Based on simulating the actual construction this paper researched the influence on the old tunnel of the new tunnel which perpendicularly passes below the old tunnel by using 3D elasto－plastic FEM． The research shows that advance force and stability ratio N are the main factors for controlling the deformation of the old tunnel．更多还原