Numerical Simulation of Compression Characteristic of Layered Rock Mass in Coal Series Strata

Abstract

Taking layered rock mass of coal series strata as the research object, numerical model of its uniaxial compression is established by FLAC3D software. The layered rock mass is regarded as discontinuous medium, and interface in FLAC3D is used to simulate layer. Compression failure characteristic of layered rock mass under the condition of single structural plane and multiple structural planes are studied systematically, and numerical solution is compared with theoretical solution. The results show that for single structural plane rock mass, under the same axial pressure, when dip is in the range of 0°-25° and 80°-90°, the compression strength does not change with dip. In the range of 25°-80°, with the increase of dip of structural plane, the compression strength curve of the rock mass shows a “U” shape, which decreases first and then increases, the change of numerical solution and theoretical solution is basically the same; When dip of structural plane is fixed and the number of structural plane in the same group increases, the compression strength of rock mass decreases with the increase of the number of structural plane. This is because rock mass with multiple structural planes is relatively broken, the compression strength of rock mass is reduced. The research results can provide theoretical reference for stability analysis of surrounding rock in stope and tunnel.