地铁隧道竖井支护结构的空间合理布局

Spatial Reasonable Layout of Shaft Support Structure for Metro Tunnel

受周边城市道路及既有建筑影响,暗挖隧道施工的竖井空间有限。支护结构空间布局将影响其出渣效率,因此支护结构空间布局合理性对暗挖隧道施工将产生显著影响。针对开挖过程中竖井变形和空间布局,以青岛某地铁隧道暗挖施工竖井为背景,利用现场实测与数值模拟相结合的方法,采用竖井开挖引起的周边地面沉降、井壁水平变形以及洞口有效面积率作为竖井变形控制效果和空间布置合理性的评价指标,对比分析环框梁和横撑支两种支护形式的差异。研究结果表明:洞口有效面积率相同时,环框梁的支护变形控制效果优于横撑支护,并兼顾竖井变形和平面布置合理性,确定了较合理的环框梁尺寸。

By the roads and existing buildings of surrounding cities,the construction of underground tunneling space is limited. The rationality of the layout of the supporting structure will influence its slag efficiency,so the rational layout of the supporting structure will have a significant effect on the construction of the tunnel. According to the method of field measurement and numerical simulation, the surrounding ground subsidence caused by shaft excavation,the horizontal deformation of the borehole wall and the deformation of the borehole wall were carried out based on the excavation of a metro tunnel in Qingdao. The effective area ratio is used as the evaluation index of the shaft deformation control effect and the rationality of the spatial arrangement,and the difference between the two kinds of support forms was analyzed. The results showed that with the effective area ratio of the hole unchanged,the control effect of the ring beam is better than that of the bracing, and the rationality of the deformation and the layout of the shaft is taken into account.