The Determination Of Release Rate Of The Surrounding Rock And Study On The Mechanical Property Of The Tunnel Structure

As China's economic developing,the requirements of road grade are higher and higher,a large number of road tunnels have emerged as.Tunnel excavation and construction in support, surrounding rock stress release,causing cave-wall stress redistribution occurs when such a re-distribution of stress over the limit of the intensity of the surrounding rock,the rock will result in loss undermine the stability,so the release of stress-rate in the process of the tunnel construction determines the initial support of the tunnel lining and secondary support of the Security played an important role,which determines the structure of the tunnel's design is reasonable,as well as for rock tunnel Stability and reliability evaluation of the supporting structure of an important factor.The paper relys on the tunnel project of Inner Mongolia Alatan,using ANSYS finite element analysis software to build elastic-plastic model of the rock tunnel excavation process and the supporting structure to carry out numerical simulation.In this article,respectively, simulates the III and IV grades tunnel wall section,the wall of the tunnel excavation in the anchor bolting after the displacement and stress analysis to determine when a reasonable stability of the surrounding rock stress release.As well as the rate of rock excavation of the affected area.Analysis of the mechanical properties in the early support and secondary support lining under a reasonable rate of the release of stress,and then contrast to "the tunnel road design specifications",do the preliminary design for safety evaluation,and then made to optimize the initial anchor Spray support and secondary lining support structure to guide the design and construction.In the project site,the tunnel excavation carried out in a timely manner after the beginning of spray anchor support,control stress and deformation of the surrounding rock,self-sufficient so that the surrounding rock solid and play arch effect,at the same time strengthen the monitoring,timely feedback on the tunnel wall and support the mechanical behavior of systems analysis.