盾构下穿情况下的桥梁桩基托换与切桩技术

Pile Underpinning and Removing Technology under the Condition of Shield Tunneling

研究了杭州地铁2号线一期工程盾构隧道穿越桥桩基的问题,结合既有桥梁的结构形式、施工条件和工期,研究和提出了适合本工程的基础托换方案、盾构机直接切桩施工方案及相应的地基加固处理方案。施工期间的现场监测结果表明,桥梁结构的沉降变形在监测预警值范围内、桥梁结构完好,说明采用的设计和施工方案是安全可行的。

Studying the problem of shield tunnels crossing through bridge pile foundation of the Hangzhou Metro Line No. 2 project. Based on the survey of the existing bridge structure, construction condition and period, a suitable design and construction scheme for this project including pile underpinning technology,construction design of cutting pile directly by shield machine and the corresponding foundation reinforcement scheme. The monitoring results during construction show that the deformation of bridge structure is within the range of warning value and the bridge structure is in good condition. It shows that the design and construction scheme adopted in this project is safe and feasible.