盾构隧道障碍人工扩孔桩拔除施工技术

摘要

结合武汉轨道交通四号线工程中需要穿越大量已有人工扩孔桩的情况，分析了扩孔桩拔除工程中桩体拔除不彻底、拔除安全风险高、连续墙成槽施工易坍孔、旧桩质量差等难点，并提出了人工挖孔扩孔桩拔除的“先桩周后主桩身”施工方法及其工序，进而针对桩身扩径和倾斜、旧桩断裂与绳具破损等问题设计了施工应急预案，可以为类似工程提供一定的借鉴。%Combining with the fact that there are many artificial exoande oaoer analyzes the difficulties in oulling exoanded oiles,including insufficient oulling,high safety risk inoulling,frequent collaose in grooving, and ooor quality of the old oiles,and ooints out the construction methods of oulling oile surroundings before the main oiles and its construction orocedure,and designs the emergency schemes for the hole exoansion and inclination,the broken old oiles and damages at rooes,so it orovides reference for similar orojects.