Ya Lu Expressway Tunnel Bias The Numerical Simulation And Monitoring Measurement

During construction of mountain tunnels, the unsymmetrical loading of tunnels are the familiar geological hazards, especially in western China. If the unsymmetrical loading of tunnels are not to be handled properly, not only the construction period is delayed and the huge economic losses is caused, but also the secondary disasters may be arose. These will be a serious risk to the personnel safety of the tunnel builders.For the problems of unsymmetrical loading of tunnels, the paper depends on a certain tunnel in Ya-Lu high-way, and the tunnel excavation is simulated by using numerical simulation with ANSYS, then the danger spots are analyzed that may occur geological hazards during construction of unsymmetrical loading tunnel. In addition, the implementation methods for monitoring and measuring of tunnels are studied more comprehensively. Especially to the monitoring and measuring of unsymmetrical loading of tunnel, the absolute displacement measurement methods should be used for it. The paper carries out the study in several directions below.(1) the tunnel excavation is simulated by using numerical simulation with ANSYS, and the surrounding rock stress, the strain state and the supporting structure in different stages of the excavation of unsymmetrical loading tunnels are gotten, Then the danger spots are analyzed that may occur geological hazards during construction of unsymmetrical loading tunnel.(2) For the defects that occurred during construction of unsymmetrical loading tunnel, the main reasons of the defects occurrence are analyzed by from three aspects:the terrain, the geologic agent, the climatic factor, and the construction factor, then the treatment schemes are studied, and some valuable suggestions are proposed for the treatment schemes and preventions of unsymmetrical loading tunnels.(3) The implementation methods for monitoring and measuring of tunnels are studied and summarized, and own notions of the monitoring and measuring of unsymmetrical loading tunnels are established. It provides a scientific method of monitoring techniques for the safety construction of unsymmetrical loading tunnel, and have great values.(4) According to the field dates of convergence and deformation about surrounding rock, inverse analysis of displacements are made by ANSYS in unsymmetrical loading section, and some useful conclusions are obtained by comparison of the obtained dates and the design information.In brief, the purposes of this paper is to make the tunnel workers have a deep understanding to the tunnel design, construction, monitoring and measurement in the macro-and micro-view, and offer the reference for the safe, economical, rapid construction of the tunnel.