大直径盾构穿越桥梁桩基的安全性分析

Security Analysis of Large Diameter Shield Tunneling Through the Bridge Pile Foundation

以天津地下直径线为依托工程,以大直径盾构近距离穿越金刚桥桩基为例,利用MidasGTS软件建立三维模型,对盾构施工过程进行数值模拟,通过对比金刚桥6号和7号桩基在加固和没加固处理条件下盾构掘进对桩基位移的影响,分析了盾构穿越后金刚桥桩基的安全性.计算分析表明,选择隔离加固桩基,可有效减小盾构施工造成的桩基位移,加固效果明显,为盾构施工安全穿越金刚桥桩基提供了依据.

Based on the underground diameter line engineering in Tianjin,taking large-diameter shield closely through Jingang Bridge pile foundation as an example,the Midas-GTS software is used to establish a three-dimensional model and to simulate the shield construction process numerically. Compared with the influence of shield tunneling on the displacement of pile foundation by comparing Jingang bridge No. 6and No. 7 pile foundation under the conditions of the reinforcement and no reinforcement,the security of Jingang Bridge pile foundation after shield through pile foundation is analysed. Computational analysis shows that the choice isolation reinforced pile foundation can effectively reduce the displacement of pile foundation caused by shield construction,and the reinforcement effect is obvious. It provides the basis to shield constrnction safety through the bridge pile foundation.