盾构隧道下穿桥梁引起桩基变位的数值分析  

Numerical Analysis of Bridge Pile Deformation Caused by Shield Tunnel Construction underneath

作　　者：彭坤[1] 陶连金[1] 高玉春[1] 王枫[1] 黄俊[1] 

机构地区：[1]北京工业大学建筑工程学院,北京100124

出　　处：《地下空间与工程学报》2012年第3期485-489,共5页Chinese Journal of Underground Space and Engineering

基　　金：国家自然科学基金资助项目(2007CB714203);北京市自然科学基金;北京市教育委员会科技计划重点项目(KZ200910005009);国家"十一五"科技支撑计划(2006BAJ27B05)

摘　　要：依托某地铁盾构隧道下穿既有桥梁桩基工程,考虑实际的工程地质水文地质条件、上部桥梁结构传递到承台顶的荷载、盾构设计及施工参数等因素的影响,建立FLAC3D数值计算模型,模拟盾构隧道顺桥向穿越桥梁桩基的全过程,对两种不同的桩基加固方案条件下地表沉降和桩身变形规律进行了分析。研究结果表明:隧道开挖引起桩的挠曲,桩身的水平位移随桩洞距离增大而减小;后开挖侧的桩身位移比先开挖侧大;桩和承台约束了地表的沉降。Based on a typical subway shield tunneling under bridge pile foundation with considering the factors such as the actual engineering geology and hydrogeology conditions,pile load transferred from bridge structure to the pile cape, shield design and construction parameters, a numerical calculation model with FLAC3D is built to simulate whole processes of shield tunnel passing under the bridge. In terms of two different pile foundations reinforcement schemes, analysis on ground settlements and pile deformation are carried out with the 3D model. Results show that： Deflection of the pile caused by tunnel excavation and the horizontal displacement of the pile decrease with the pile and hole distance; the displacement of pile body for latter excavation is larger than that for the former excavation; Piles and beating platforms constrain the surface subsidence.

关 键 词：盾构隧道 地表沉降 数值模拟 FLAC3D 桩基 加固 

分 类 号：TU941[建筑科学—建筑技术科学] TU942