Research on the Destructional Pattern of Surrounding Rock of Roadway Induced by Dynamic Disturbance

The low frequency strong-dynamic disturbance is one of the sources of deformation and failure of surrounding rock in rockburst roadway, but its deformation and failure mechanism and spectrum characteristics still need further study. In this paper, we selected 4 levels and 5 factors with an orthogonal test approach to study the stability of surrounding rock under dynamic disturbance (stress-time curve), the 5 factors are rock level (uniaxial compressive strength sigma(c)), disturbance stress sigma(d), frequency f, burial depth H and propagation direction theta), respectively. The orthogonal test result indicated that the pecking order of lambda, an coefficient has a bearing on the plastic area, is as follows: A(sigma(c)), B(sigma(d)), E(theta), C(f), D(H). Based on the engineering background of rockburst roadway in Qianqiu coal mine in Yima mining group, the spectrum characteristics of rockburst vibration wave and the failure law of roadway surrounding rock were studied by similar simulation experiment method. The test results show that with the increase of roof pressure, the load of the roof-floor and two sides first increase, then decrease and tend to be stable. After the dynamic disturbance, the acceleration waveform of the roadway surrounding rock measurement points lasts for about 0-0.05 s, attenuates quickly, the coda develops well, the frequency range of disturbance wave is wider, and the amplitude is larger, which is mainly manifested by more high-frequency components. The surrounding rock of roadway cracks increase, develop, and large fissure were formed through the cracks, the roof and side rock strata of the roadway fall off, and the deformation and destruction of the roadway was severely damaged.