Monitoring And Numerical Simulation On The Surrounding Rock Stability Of Xin Cheng Gold Mine-536m Mining Tunnel

Along with the increase in depth of mining, surrounding rock stress environment has changed, what made the structural characteristic and mechanical behavior more complex, then roadway stability control has become difficult, working environment became much dangerous, the cost of production has risen sharply. The stability of excavation has been one of main problems having an influence on the mine production.Based on the engineering background of Xin Cheng Gold Mine, by the means of theoretical analysis, field researching, mechanics experiment and numerical simulation,it offers a base for the paper making an in-depth study on the deformation mechanism and characteristics of the surrounding rock under high stress, including following works:Firstly, field researching, sampling and measuring in lab give a way to get the field rock mechanics parameter, and it offers a reliable date for the numerical model.Then, the sensitive test design approach on orthogonal table is used to analysis the parameter: residual cohesion, residual friction angle and plastic strain, finding the influence degree of every factor to the excavation. Further, making a comparison between the elastic-plastic model and strain-softening model proves that the latter can reflect the failure rule of roadway surrounding rock better and character the stress transfer to the deep. On the basis of obove, the paper uses the model to simulate the excavation progress of roadway and block, besides, studies the disturbance range and evolution rule of stress and displacement field of the surrounding rock.Finally,the displacement convergence meter and force measurement anchor are installed in the -536m level, monitoring the deformation and anchor evolution rule during the roadway and block excavation progress, then, making a comparative analysis with the simulation outcome, proving the rationality of using strain-softening model in predicting the excavation failure zone of surrounding rock in deep tunnel. The research has a role in guiding people to learn the excavation failure process of surrounding rock, judge stability and predict the excavation failure zone of tunnel.