Construction Of The Mechanical Behavior And Safety Control Measures. Tunnel Proximity Bridge And Culvert Structures

The passenger dedicated line between citis is highly developing in domestic. A serious challenge of construction in super large section tunnel is proposed on the basis of complexity of urban project, variety of hydrogeology conditions , plenty of surficial construction and underground pipelines. Another phenomenon also influence the construction of super large section tunnel in passenger dedicated line which is rapid development of passenger dedicated line between cities and the increased of long-big railway tunnel crossing the city. Therefore, numerical simulation, engineering analogy and field test are used relying on Liu Yang River tunneling engineering of Wuhan-Guangzhou passenger dedicated line. In the further studying, construction mechanics behavior and safety control measures are analyzed. Four major tasks are given as follow:(1) Two-dimensional numerical model and three-dimensional numerical model of construction process to interchange overpass underneath pass tunnel is presented as difference forced state of the deformation of the surrounding rock and supporting structure. Then the stability judge of surrounding rock in excavation process is obtained. The interaction of tunnel construction, surrounding rock and bridge foundation are displayed basing on the analysis result of surrounding rock stress, deformation, plastic zone, bridge foundation stress and trend of settlement between piers in excavation progress.(2) Two-dimensional numerical model and three-dimensional numerical model of tunnel box culvert is established using numerical simulation technology on the basis of large section water discharge box culvert underneath pass tunnel. Key construction step and optimization construction process is obtained at the same time when the characteristic of box culvert deformation and ground settlement in difference tunnel excavation sequence. Safety of large section water discharge box culvert underneath pass tunnel is demonstrated by analysis result of surrounding rock and box culvert stress.(3) According to the present situation of Liu Yang River tunnel construction process and adjacent bridge and culvert structure, the deformation controlling standards of construction process which is appeared is presented referring to relevant standards and similar project experience.(4) Safety control measures in the tunnel construction process are proposed through the numerical simulation result and deformation of bridges and culverts structure caused by tunnel construction.