Theoretical analysis for rheological characteristics of surrounding rock and on-site monitoring in Longshou mine

The rock mass rheological characteristics of Longshou mine were studied by FLAC3D numerical analysis software. The results show that the rock creep rate increases and rock damage, deformation and failure process accelerates with the increase of confining pressure. The impacting law of confining pressure on rock rheological properties is revealed. The deformation of surrounding rock mainly presents as dilatancy deformation after peak strength, and the sensitivity of confining pressure is more obvious when the confining pressure is lower. While the confining pressure is less than 4 MPa, the affecting degree reaches to 70%-80% of rock volumetric strain. The on-site monitoring of bolt stress and roadway deformation is conducted to explore the rock mass rheological rule and supporting effect. The results indicate that the anchoring force is just 9.15%-33.79% of the anchoring capacity, insufficient to suppress the rock deformation. The deformation rate is 0.043-0.149 mm/d and has a slowing down trend, but the amount of deformation increases gradually, with a greater horizontal convergence than the vertical of that, which is not conducive to the stability of surrounding rock, so the appropriate reinforcement measurements should be adopted. ©, 2014, Academia Sinica. All right reserved.