盾构法隧道下穿既有结构三维数值模拟分析  

Three-Dimensional Numerical Simulation Analysis of the Shield-Driven Tunnel Crossing under the Existing Structure

作　　者：杨广武[1] 关龙 刘军 郑知斌[3] 

机构地区：[1]北京交通大学,北京100044 [2]北京市政集团,北京100045 [3]北京市市政工程研究院,北京100037

出　　处：《中国铁道科学》2009年第6期54-60,共7页China Railway Science

基　　金：北京市政总公司(集团)基金资助项目(科-J-06116)

摘　　要：以北京地铁10号线9标段盾构法开挖隧道穿越城铁13号线芍药居车站工程为依托,采用三维有限差分软件FLAC3D对盾构施工过程进行数值模拟,分析盾构穿越既有结构时对其沉降的影响规律。研究结果表明:既有线车站结构的沉降随地基变形模量的提高而减少,且沉降趋势逐渐变缓;既有结构最大沉降增大的速率比围岩荷载释放率增大的速度快;增大开挖面的控制压力,可有效减小既有结构的沉降,但过大的控制压力会使前方土体隆起,产生负地层损失,并且随着开挖面控制压力的提高,差异沉降明显增大。通过施工参数的优化可以减小既有结构的沉降,达到保护既有结构的目的。The influence law was analyzed when shield-driven tunnel crossing under the existing subway station by using FLAC^3D numerical simulation method on the basis of No. 9 area shield-driven tunnel of Line 10 crossing Line 13 at Shaoyaoju subway station in Beijing. The research results indicate that the subsidence of the existing subway station may decrease gradually when the deformation modulus of ground soil is increased. The subsidence rate of the existing construction is faster than the load release rate of the surrounding soil. The subsidence of the existing construction can be reduced obviously through increasing the control pressure of the excavation surface, but the excessive control of pressure may produce the hunch of shield-driven machine frontal soil. The differential subside may increase obviously when the control pressure is continually increased. On the basis of these results mentioned above, the existing subway station can be protected well by optimizing the construction parameters of shield-driven machine.

关 键 词：隧道 盾构法 既有结构 变形 数值模拟 

分 类 号：U455.43[建筑科学—桥梁与隧道工程]