Study On Failure And Stability Mechanism Of Rock In Deep Roadway Under Dynamic Disturbance

Deep rock mass in the mining process, not only bear the high static load, but also suffer the effects of dynamic load, such as blasting vibration and mining roof breaking.It leads to that rock’s stress state is very complex, mainly under high crustal stress and dynamic load. Deformation and failure of deep rock mass can be considered as the result of the effect by dynamic load in static stress condition substantial. Therefore, the study on the mechanical properties of deep rock mass under static and dynamic loads, especially the dynamic disturbance on failure and stable of rock mass under high capacity has important theoretical significance. In this paper, the mechanism of failure and stability of surrounding rock in deep roadway under dynamic disturbance was investigated through theoretical analysis, numerical simulation and other methods, the main results are as follows:(1) Based on the basic characteristics of the deep roadway, analysis on stress weight distribution and energy evolution from accumulation to dissipation and transfer of surrounding rock under static loading in the of deep roadway, and sums up the characteristics of static ioad,such as uniform stress distribution and high degree of concentration, storage of high energy and unstable distribution; analysis of disturbance propagation and energy propagation of stress wave in rock mass, and summarized the characteristics of dynamic load in deep roadway,such as volatility propagation, attenuation propagation and multiple disturbance.(2) Study on the mechanical properties of rock under different static and dynamic load preliminary, the mechanical properties of rock under static loading, the mechanical properties of rock under the dynamic load uniaxial impact disturbance and the mechanical properties of rock under 3D static and cyclic loads; analysis of the effect on the failure process of rock under the combined action of static and dynamic load by static axial pressure, static pressure and dynamic stress amplitude and dynamic load stress wave.(3) Through the numerical simulation software FLAC3 D and analysis of distribution and the perturbation size of deformation, stress, rupture area of surrounding rock in deep roadway, study on the effect of different depth and different lateral pressure coefficients, different amplitude of stress wave and different stress wave time delay on the stability of roadway surrounding rock; reveal the deformation and failure characteristics of surrounding rock under different stress and different dynamic load disturbance conditions; and analyze the influence of disturbance effect under different conditions on instability rockburst tendency.(4) According to the results of numerical analysis, put forward the stability control thinking of surrounding rock through weaken static load, reduce dynamic load and weaken effect of dynamic load disturbance, constructed the supporting form of the anchor net spray +U shed stent +backwall grouting+ buffer weak structure to weak the disturbance effect of dynamic load on the surrounding rock.