浅埋小净距双线隧道平行下穿既有道路设施工法影响研究

Research on Impact of Construction Method of Shallow-buried Double Track Tunnel with Small Clear Distance Undercrossing the Existing Road Facilities in Parallel

以北京地铁某区间隧道下穿朝阳门外大街项目为工程依托,分析了小净距双线隧道平行下穿既有道路时,不同施工工法对道路设施的影响程度。采用有限元软件对留核心土台阶法、CD法及CRD法进行施工模拟计算,结果表明:在三种工法中台阶法施工影响范围最大且路面沉降超过规范中所规定的沉降控制值,CD法及CRD法施工导致路面沉降满足规范要求,但CRD法变形控制能力优于CD法,为尽可能保证下穿道路的结构安全,建议该项目应优先考虑采用CRD法进行施工作业。

Based on the project of Beijing metro tunnel undercrossing Chaoyangmenwai street,the impact of different construction methods on road facilities is analyzed when the double track tunnel with small clear distance undercrossing the existing road in parallel. The finite element software is used to carry out the construction simulation and calculation for the core soil retaining bench method,CD method and CRD method. The results show that: among the three construction methods,the bench method has the largest impact range and the pavement settlement exceeds the settlement control value specified in the specification. The construction of CD method and CRD method causes the pavement settlement to meet the specification requirements,but the deformation control ability of CRD method is better than that of CD method. In order to ensure the structural safety of underpass as much as possible,it is suggested that CRD method should be given priority in the construction of this project.