新建公路近距离上跨既有铁路隧道力学效应影响分析

Analysis on Mechanical Impact of Newly-built Highway Overcrossing Existing Railway Tunnel at Short Distance

以西双版纳新建公路上跨既有玉磨铁路南联山隧道工程为依托,基于有限元软件ANSYS建立隧道结构三维力学模型,模拟公路路基施工前、施工中和运营期的各种工况,分析隧道结构位移、应力、内力和安全系数等变化规律;采用监控量测验证计算分析的准确性。结果表明:新建公路路基施工引起隧道结构最大附加位移0.3 mm,最大附加拉应力0.3 MPa,最大附加压应力0.8 MPa,最大附加内力88.5 kN,最小安全系数3.73;新建公路施工及运营期隧道结构位移、应力、内力和安全系数均满足规范要求。

Based on the Nanlianshan Tunnel project of a newly-built highway overcrossing the existing Yumo Railway in the Xishuangbanna Tourism and Resorts District,the three-dimensional mechanical model of the tunnel structure is established based on the finite element software ANSYS to simulate various conditions of the roadbed before and during construction and during the operation period and analyse the change laws of the tunnel structure displacement,stress,internal force and safety factor.The accuracy of calculation and analysis is verified by monitoring and measuring.The results show that the maximum additional displacement of the tunnel structure caused by the construction of the newly built highway subgrade is 0.3 mm,the maximum additional tensile stress is 0.3 MPa,the maximum additional compressive stress is 0.8 MPa,the maximum additional internal force is 88.5 kN,and the minimum safety factor is 3.73.The displacement,stress,internal force and safety factor of the tunnel structure during construction and operation of the newly-built highway all meet the specifications requirments.