钢轨劲性水泥土搅拌桩墙在天津地铁既有线车站改扩建工程基坑中的试验研究

Experimental Study on Application of Rigid Rail-Cement-Soil Mixing Piles in Foundation Pit of Rehabilitation Project of Existing Station of Tianjin Metro

天津地铁既有线改扩建工程车站出入口基坑开挖深度为6-7m,加上基坑处闹市区、距离建筑物非常近,且坑边管线多,为适应工程场地条件并节约造价,围护结构采用了在水泥土搅拌桩受拉区插入地铁旧钢轨所形成的劲性水泥土搅拌桩连续墙,论文主要介绍钢轨劲性水泥土搅拌桩连续墙施工工艺、钢轨水泥土组合墙工作性能和钢轨起拔的试验情况,试验得出的结论直接指导了其在工程中的安全应用,对类似工程具有一定的指导与借鉴作用。

The foundation pit for the entrance and exit of the rehabilitation project of an existing station of Tianjin Metro is 6-7 m deep.The foundation pit is located in downtown area and is surrounded by buildings and utility pipelines.Used rails are inserted into the tensioning area of the cement-soil mixing piles to form retaining structures consisting of rigid cement-soil mixing piles.Such retaining structure is adopted for the foundation pit in order to meet the requirements of the site conditions and to reduce the construction cost. The experiment on the construction workmanship, performance and rail lifting of the retaining structure consisting of rigid rail-cement-soil mixing piles are presented in the pa- per. The conclusions drawn have provided direct guidance for the safe application of this construction technology in the project. The paper can provide reference for similar projects in the future.