设置地下存车线的地铁区间大断面暗挖的顺挖技术研究

Vehicle Storage Track Tunnel Built with Shallow Underground Excavation in Lager Cross-section

地铁的地下存车线段采用浅埋暗挖法施工时,通常由小断面的横通道正向扩挖切入渡线段大断面,再反向二次扩挖形成区间隧道,其结构断面变化多,施工方法转换复杂,存在多种不利工况。研究了在存车线段的渡线中点处设置横通道,正线断面均可由大到小顺挖,避免了顺扩、反扩等工况。并对由此引起的高断面马头门、横通道两侧不对称开挖、结构抗震等进行分析研究,提出了相应的针对性措施。

Metro vehicle storage track tunnel adopts the shallow underground excavation method,in which usually the excavation is positively from light cross-section （using for gallery） to large cross-section （for metro crossover）,then the excavation is expanded in reverse for the metro tunnel.Due to the fluctuation of structural fracture section and the complicated construction methods,there will be several disadvantages during the construction process.In this paper,the method of setting a gallery in the center of crossover is discussed,which can excavate from large cross -section to light cross-section and thus avoid the reversed excavation.Also,the lager cross-section in gate,in unsymmetrical excavation and structural seismic situations in the construction process are analyzed,some corresponding measures are put forward.