新建公路隧道下穿既有铁路隧道施工安全影响分析

Impact Analysis of Construction Safety of Newly-established Highway Tunnel Passing Through the Existing Railway Tunnel

以温岭市华盛路北沿工程新建楼旗尖隧道下穿既有温玉铁路楼旗隧道为例,通过三维有限元数值计算模拟分析了新建公路隧道下穿既有铁路隧道施工过程,得到既有铁路隧道衬砌结构在附加荷载作用下的收敛变形和安全系数。结果表明:新建公路隧道施工完成后,既有铁路隧道衬砌结构的累计最大竖向和水平向位移值分别为0.938mm和0.223mm,小于规范要求的预警值(±3mm),衬砌结构安全系数检算结果满足相关规范要求。

Taking the newly-established Louqijian tunnel of the north extension project of Huasheng road in Wenling passing through the existing Louqi tunnel of Wenyu railway as an example,the construction process of the newly-established highway tunnel passing through the existing railway tunnel is simulated and analyzed by the three-dimensional finite element numerical calculation,and the convergence and deformation and safety factor of the lining structure of the existing railway tunnel under the action of additional load are obtained.The research results show that:after the construction of the newly-established highway tunnel,the cumulative maximum vertical and horizontal displacement values of the lining structure of the existing railway tunnel are respectively 0.938mm and 0.223mm,which are less than the early warning value(±3mm)required by the code,and the safety factor calculation results of the lining structure meet the requirements of the relevant code.