富水砂层区盾构下穿建(构)筑物风险控制技术研究

Risk Control Technology of Shield Tunneling Structure in Water Rich Sand Layer Area

以太原地铁2号线一期工程双塔西街站-大南门站区间为研究对象,通过采取掘进施工前对下穿建(构)筑物进行鉴定评估、隔离加固,掘进过程中合理选择与优化掘进参数、地表跟踪注浆,下穿通过后洞内补充注浆等风险控制措施,双大区间顺利下穿10个建(构)筑物Ⅱ级环境风险源。通过对区间下穿建(构)筑物变形监测数据进行统计分析,结合该区间地下水埋深浅、砂层敏感性强等水文地质特点,对盾构下穿建(构)筑物风险控制技术进行研究。工程实践表明:富水砂层区盾构下穿建(构)筑采取以盾构自身掘进参数控制为主,隔离加固、地表跟踪注浆等措施为辅风险控制措施,可以有效控制建(构)筑物变形。

In this paper, the tunnel from Shuangtaxijie station to Dananmen station of the first phase of Taiyuan metro line 2 is taken as the research object. Before the tunneling construction of the tunnel, the underground construction should be appraised, isolated and reinforced. During the course of driving, driving parameters and surface tracking grouting should be selected and optimized. After underpass, additional grouting and other risk control measures shall be taken in the tunnel. Shuangtaxijie station to Dananmen station tunnel successfully went through ten building which are level 2 environmental risk sources. Based on the statistical analysis of the deformation monitoring data of the underpass construction in this area, the risk control technology of the underpass construction under shield construction is analyzed in combination with the hydrogeological characteristics such as the depth of underground water and the sensitivity of sand layer. The engineering practice shows that the construction of shield tunneling in water-rich sand zone can effectively control the deformation of shield tunneling by controlling the tunneling parameters of shield tunneling itself, and taking measures such as isolation reinforcement and surface tracking grouting as auxiliary risk control measures.