浅谈地铁辅助通道进隧道正线初期支护体系转换施工技术

Discussion on transform construction technology for primary support system of auxiliary access of subway to the main tunnel

针对城市地铁辅助通道进隧道正线施工,辅助通道位置开洞部位较多,围岩扰动次数多,土体受力转换复杂,结构受力薄弱的特点,在系统分析了隧道周围岩土体变形机理基础上,提出了一种全新的辅助通道门式钢架扩挖进隧道正线施工方法。通过对三种不同辅助通道进隧道正线施工方案对比,对其施工进度、风险、成本、沉降控制及支护体系转换等进行了多方面分析,以选择合理的施工方案,对类似工程施工具有一定的指导意义。

In view of the construction of the main entrance of the auxiliary tunnel of urban subway, there are many holes in the auxiliary passage way, the disturbance of surrounding rock is frequent, the transform of stress of the soil is complex, and the structural stress is weak. On the basis of systematic analysis of the deformation mechanism of tunnel surrounding rock and soil mass, a brand new auxiliary channel portal steel expansion and excavation method is put forward. The construction schedule, risk, cost, settlement control and support system conversion are analyzed through the comparison of three different horizontal tunnel construction schemes. The selection of reasonable construction scheme is of certain guiding significance for similar engineering construction.