多线叠交盾构隧道近接施工模型试验

Model Test on Approaching Construction of Multi-line Overlapped Shield Tunnelling

多线叠交软土盾构隧道是随地铁建设不断发展而出现的一种复杂隧道空间布置形式.针对多线叠交盾构隧道垂直上、下穿2种典型穿越施工形式,借助室内模型试验,根据盾构隧道近接施工的技术特点和控制要求,采用排液法,重点分析了多线叠交盾构隧道在各穿越阶段下因地层损失和开挖卸荷引起的地表沉降以及既有隧道纵向变形规律.分析结果可为今后类似多线叠交盾构隧道工程的设计和施工提供理论指导.

With the unceasing development of the metro construction, multi-line overlapped shield tunnels in soft soil are being built as a complex spatial distribution. For two kinds of typical construction methods of up-crossing and under-crossing, model test research was applied to analysis the dynamic construction process. According to the shield tunneling technology characteristics and control requirements of approac- hing construction, the drainage method was applied to selective analysis of the surface subsidence and the existing tunnel longitudinal deformation caused by formation damage and excavation unloading of multi-line overlapped tunnel at various stages. The research results can provide some theoretical basis and prophase guidance for similar projects in the future.