Analysis Of Stress And Deformation Of Railway Tunnel Crossing Underneath Highway

Along with the reform and opening up, China’s economic and society get high speed development, the people travel transportation improved, all kinds of traffic lines often overlap. New railway tunnel tend to cross the arterial road, the turbulence caused by wear under construction makes the stress and deformation of highway structure redistribute, and affects the normal use of highway. This paper is based on the project of three south railway fengjujiang tunnel crossing the YuXiang highway in ChongQing, using the finite element software to simulate different excavation footage, tunnel buried depth, surrounding rock condition, construction settlement control level, deformation cracks, concluding the highway press and deformation law.By security, stability and functional requirements of road-surrounding rock-tunnel system, the paper put forward the corresponding settlement of highway control standards.This paper completed following aspects:Firstly, the paper collected a lot of examples of similar projects at home and abroad, enumerated tunnel excavation methods, support form, settlement control standard, and the details of measured maximum settlement,also analyzed the destruction form of highway structure.Secondly,the paper set up three-dimensional finite element model to simulate the tunnel excavation, considering of the tunnel excavation footage, settlement control level, geological conditions, tunnel buried depth and road deformation cracks, conclude the law of the highway press and deformation.Taking road tensile strength and road roughness as a standard(1.2Mpa,0.1%),the paper calculated road control standard of highway to meet the requirement of security, stability and function of road-surrounding rock-tunnel system;It is concluded that the deformation and stress of the highway meet the requirement of road criterion when the road surface maximum settlement is less than 23.9 mm.Thirdly,considering of the settlement control idea "reduced","compensation" and "cut off’,put forward reasonable reinforcement measures from the impact of highway structure tensile strength,road roughness.Barrel vault advanced support is the best support method for the engineering.