引水隧道下穿铁路线路基沉降的数值分析

Numerical analysis on the subgrade settlements caused by tunneling across railway

以福建省九龙江北引引水隧道下穿铁路线为研究对象,采用软件FLAC3D分析双洞引水隧道的下穿开挖对鹰厦铁路双线、厦深高铁双线的铁路路基的影响,通过模拟路基未加固和加固2种工况下,隧道单线贯通及双洞贯通后的路基的沉降情况.计算结果表明:最大沉降位于两隧道中心线正上方,路基未加固:右洞开挖对路基沉降的贡献64%左右,左洞贡献36%左右;路基加固:线开挖对路基沉降的贡献66%左右,左洞贡献34%左右.对比实测数据较为一致,证明拟合较好.

Based on the draw water tunnel of the Jiulong river across railway in Fujian Province as the research object,the finite element analysis software FLAC3D was used to analysis the double draw water tunnel excavation influence of the subgrade,to the double railway of Yingtan -Xiamen and the double railway of Xiamen -Shenzhen. Through simulation the two condition of subgrade unreinforcement and subgrade reinforcement,the situation of settlement of subgrade was analysed when in single tunnel perforation and double tunnel perforation.Research shows that：the position of maximum settlement is just above the the tunnel centerline,the proportion of subgrade settlement caused by the right line excavation is 64% and caused by the left is 36% when subgrade unreinforcement,the proportion of subgrade settlement caused by the right line excavation is 66% and caused by the left is 34% when subgrade reinforcement.The results fit well with monitoring data.