零距离近接既有地铁站施工监测与数值模拟分析

本文以天津地铁5号线思源道站结建工程为背景,从施工监测和数值模拟两方面对基坑施工过程的变形控制进行研究。通过对周边环境、深层位移、基坑自身支撑体系等进行监测,实现工程施工全过程数据信息的无缝对接和实时反馈,保证了既有地铁站安全运营。建立数值仿真模型,对基坑周边环境竖向沉降、水平位移、基坑自身支护体系受力变化等进行研究分析,验证基坑开挖方式的可行性。研究结果表明,对于零距离近接既有地铁站地下空间拓建施工,基坑采用分层岛式开挖及地下连续墙+混凝土环形内支撑支护体系,能有效地控制基坑变形,确保周边环境和基坑自身安全。

Analysis on Construction Monitoring and Numerical Simulation of Zero-distance Adjacent Existing Subway Station

Based on the construction project of Siyuandao Station of Tianjin Metro Line 5,this paper studied the deformation control of deep excavation process from construction monitoring and numerical simulation.Through monitoring the surrounding environment,deep displacement and self support system of deep excavation,the seamless connection and real-time feedback of data information in the whole process of construction was achieved,the safe operation of the existing subway station was guaranteed.The numerical simulation software was used to build the model,and the vertical settlement,horizontal displacement and stress variation of the excavation supporting system were studied and analyzed to verify the feasibility of the excavation method.The results show that,for the expanding construction of underground space close to the existing subway station at zero distance,if thelayered islandexcavation anddiaphragm wall plus concrete ring inner supportsupport system are adopted,the deformation of deep excavation can be effectively controlled,and the safety of surrounding environment and deep excavation can be ensured.