地层变位分配控制原理在小间距偏压突变大断面隧道中的应用研究

利用分步变位控制原理研究复杂地质浅埋暗挖小间距偏压突变隧道施工过程中地层变形规律,对限制周边环境及结构本身复杂的隧道工程地表变形具有指导意义。依托深圳地铁7号线工程实例,分析地表在多种复杂条件下的变形规律,结果表明,数值模拟过程中,注浆体充分发挥了作用,地表竖向沉降量(最大为14.82 mm)满足标准要求,但实际监测得到的地表沉降位移明显超过标准值,因为地表变形不仅受注浆措施的控制,还会受到多种不确定因素的影响,但从现场观测结果来看,同时经相关单位论证后,表明并没有因为隧道施工影响周边建筑物的正常运行。因此保障隧道结构及周围环境安全才是最重要的,用统一标准进行地表沉降控制是不尽合理的,对处于复杂地质环境中,且结构本身复杂的隧道工程来说,日常沿用标准几乎不适用。

Application and Research of Ground Deflection Distribution Control Theory in Tunnels with Small Spacing,Unsymmetrical Load and Mutant Large-section

Studying the mechanism of surface deformation by ground deflection distribution control theory in tunnels with shallow death, small spacing, unsymmetrical load and mutant large-section under complicated geological conditions is very important to control surface deformation. With reference to Shenzhen Metro Line. 7,this paper analyzes the deformation laws of surface under complicated geological conditions. The simulation results reveal that grouting plays an important role and the ground settlement( the maximum is 14. 82 mm) meets the standard. The monitored surface deformation is well over the standard value,because the surface deformation is not only controlled by grouting,but also by many uncertain factors. The field observation indicates and the relevant authority proves that tunneling doesn't affect normal conditions of adjacent buildings. Thus,the primary goal is to ensure the safety of tunnel structures and surrounding environment,and controlling the surface settlement by only a single standard is not fully acceptable. Routine standards are almost inapplicable in tunneling project with complicated structure and in complex geological environment.