盾构区间隧道水平近距离施工方案研究

Research on the Construction Scheme of Horizontally Approaching Excavation Shield Tunnel

研究目的:盾构区间隧道水平近距离施工在国内尚无成熟的技术方案,对其进行研究,为同类工程的设计与施工提供借鉴和参考。研究方法:结合天津地铁2号线工程,采用结构平面有限元数值模拟计算与数据分析,并同国内相似工程的经验进行类比。研究结果:分析了盾构区间隧道水平近距离施工存在的风险,研究得到了相邻隧道开挖前后的结构内力、变形及其分布特征,以及沉降曲线,并提出安全施工方案。研究结论:盾构水平近距离施工时需加长对盾构周边土体的加固范围,在相邻两隧道之间设置隔离桩,同时在施工过程中需严格控制施工参数并加强监测。

Research purposes： There is no mature scheme of horizontally approaching excavation shield tunnel, so references could be provided for design and construction of the similar projects. Research methods： Base on the No. 2 line project of Tianjin metro, this paper calculates and analyzes the data by plane FEM, and studies on the similar projects inland by analogy. Research results：The potential risk of horizontally approaching excavation shield tunnel is discussed. The study elicits the internal force and deformation of the structure, and the distributing character of them, and the sedimentation curve fore -and -aft the approaching tunnel excavation, the secure construction scheme is established. Research conclusions：The strengthen scope of the earth around the tunnel should be extend in horizontally approaching excavation shield tunnel, and isolating pile measure should be adopted between tunnels, meanwhile in the construction process, the construction parameters should be strictly controlled, and monitoring should be enhanced.