Research on Safety Risk of Subway Tunnel in a Deep Foundation Pit Project
张璞 ZHANG Pu
（广州地铁设计研究院股份有限公司，广州 510010）
（Guangzhou Metro Design and Research Institute Co.，Ltd.，Guangzhou 510010，China）
摘要：地铁周边基坑开挖可能会对临近地铁隧道产生一定的负面影响，须进行可靠的安全评估。本文依托某市地铁三号线地铁站附近的基坑工程开展案例研究，初步勘察和调研研究区地质条件和风险，为后续细化的安全风险评估建立研究基础。结果表明：基坑所在区域地下水的水位较高，基坑施工过程需要专门开始止水处理；盾构隧道最大水平位移为 4.59mm，最大竖向位移为 0.83mm，均小于城市轨道交通结构安全控制指标预警值 10mm 的要求；盾构隧道弯矩最大变化值为 3kN·m/m，剪力最大变化值为 2.5kN/m，轴力最大变化值为 20kN/m，地铁结构的受力变化处于较低水平，深基坑施工不危及邻近地铁结构的安全。
Abstract: The excavation of foundation pit around the subway may have a certain negative impact on the adjacent subway tunnel, and a reliable safety assessment must be carried out. Based on the foundation pit project near the metro Line 3 subway station in a city, this paper carries out a case study, preliminarily surveys and researches the geological conditions and risks of the area, and establishes a research basis for the subsequent detailed safety risk assessment. The results show that the groundwater level in the area where the foundation pit is located is high, and the special water sealing treatment is needed during the construction of the foundation pit. The maximum horizontal displacement of the shield tunnel is 4.59mm, and the maximum vertical displacement is 0.83mm, both of which are lower than the requirement of the early-warning value of the safety control index of urban rail transit structure of 10mm. The maximum change value of shield tunnel bending moment is 3kN·m/m, the maximum change value of shear force is 2.5kN/m, and the maximum change value of axial force is 20kN/m. The force change of subway structure is at a low level, and the construction of deep foundation pit does not endanger the safety of adjacent subway structures.
关键词：地铁隧道；深大基坑；工程地质；不良地质体
Key words: subway tunnels；deep excavations；engineering geology；unfavorable geological bodies
中图分类号： TU753 文献标识码：A 文章编号：1006-4311（2024）27-050-05 doi:10.3969/j.issn.1006-4311.2024.27.015
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