Stability Analysis Of Tunnel Surrounding Rock In Coal Strata And Field Monitoring Study

The coal-bearing strata are widely distributed in western China, therefore how to ensure tunnels through the coal-bearing strata safely is a problem that deserves research very much. Relying on project of the Si Guanzhai Tunnel and the San Lian tunnel, this paper analyzes the stability of surrounding rock in coal measure strata tunnel combined with cave displacement and steel arch internal force test and finite difference software FLAC2D simulation analysis, as the basis of which tunnel construction and supporting measures are discussed.(1) Through the example of collection and analysis of coal measure strata tunnel disasters, to understand the security risks faced by the tunnel construction of coal-bearing strata and its influencing factors.(2) Displacement steel arch, internal forces, early support concrete internal forces and lining internal force of the Si Guanzhai tunnel and San Lian tunnel cave were tested to obtain the coal measure strata excavation under different initial support deformation, stress distribution and characteristics of variation, evaluating the surrounding rock stability during the construction period and the early supporting of security.(3) It simulates the coal measures strata of tunnel excavation with the limited differential software FLAC2D, and analyzes the deformation and damage characteristics and initial support structure deformation, the internal force distribution. Furthermore, evaluating the stability of surrounding rock and the security of supporting structure.(4) Si Guanzhai tunnel and the San Lian tunnel testing and numerical simulation results on the basis of the coal measure strata tunnel support measures and advance care measures are discussed, reasonable support parameters are applied in the actual engineering, and it demonstrated the safety of the tunnel construction.