顶管上穿施工对既有地铁隧道的影响

以杭州市某污水管道顶管施工上穿既有地铁隧道为背景，利用FLAC3D模拟顶管施工过程，将模拟结果与实测数据进行对比，验证了模型的合理性.通过改变顶管管径、管材及地铁隧道周围土体的特性，分析了不同工况下顶管上穿施工对既有地铁隧道的位移影响.研究结果表明，顶管上穿施工对既有地铁隧道所产生的最大位量均位移于顶管轴线下方的地铁截面处，离顶管轴线越远，变形越小；地铁盾构隧道的变形随顶管的管径的增大而增大，而且对竖直方向位移的影响远大于对水平方向位移的影响；管材的弹性模量越小，地铁隧道的变形越大；地铁隧道周围土体弹性模量越小，顶管施工对隧道位移的影响越大.

Influence Analysis of Perpendicular Crossing Pipe Jacking Constructed Above Existing Shield Tunnel

Based on the construction of a sewer pipeline built perpendicularly above a existing shield tunnel in Hangzhou,the pipe jacking construction procedure was simulated by software FLAC3D,and verified reasonable after comparing the simulation results with the measured results.By changing the pipe diameter,pipe material and surrounding soil’s characteristic of the shield tunnel,its displacement rule of existing shield tunnel was analyzed.The studies showed that the max vertical and horizontal displacement of the shield tunnel  happened under the sewer pipeline,and the further away from the pipe jacking line,the smaller the deformation;the more diameter of sewer pipeline’s pipe,the more displacements of existing shield tunnel,and the influence of the sewer pipe diameter on vertical displacement was significantly greater than the horizontal displacement;the less elastic modulus of sewer pipe,the more displacements of the shield tunnel;the more elastic modulus of the soil layer,the less displacements of the shield tunnel.