Research on Stress Distribution and Failure Depth of Mining Floor During the First Weighting of Main Roof

Abstract

In order to research stress distribution and failure depth of mining floor during the first weighting of main roof, based on the analysis of abutment pressure distribution in this case, an elastic model was established to calculate the stress of any point on the floor. The expressions for this model were deduced, and a failure criterion of floor rock was put forward according to the Mohr-Coulomb failure criteria. Taking the parameters of 3612 mining face of Zhu Zhuang coal mine as an example, and through solving stress distribution of mining floor during its first weighting of main roof, stress contour and failure district of floor were determined . The result showed that, the failure depth of 3612 mining floor is 12.4m, which is rather close to the measured value 13m, thus, the utility and reliability of this study method were effeciently verified. The result provided theoretical basis for bottom grouting strengthening before the first weighting of main roof, and established theoretical foundation for further research on safe mining of confined waters.