采空区围岩-冒落散体承载特性研究OA

To address the instability-induced disasters of goaf caused by the caving mining method,the bearing characteristics of goaf surrounding rock-caved granular were studied,and then the instability-induced disasters mechanism and prevention methods of the goaf were raised.Firstly,the deformation and crushing rules of caved granular were analyzed using the confining compression tests.Secondly,the constitutive model and instability discriminant criterion of goaf surrounding rock-caved granular were built based on the component model method.Finally,the reliability and effectiveness of prevention methods of the instability-induced disasters of goaf were verified by the mine engineering case.The collaborative scheme of caving mining method and goaf management was raised,and the engineering practice was carried out in the mine.The results show that the stress-strain curves show a"fast—slow—fast"growth law with various size distribution,and the peak strain increases with the particle size and the ratio of the broken rock height to the compacted caved granular height increase under broken rock accumulation effect.The square of the ratio of the broken rock height to the composite body height has a linear relationship with the peak strain of the broken rock-caved rock and ore combination.The instability-induced disasters index of goaf is proposed as the matching coefficient of goaf surrounding rock and caved granular.This coefficient is positively correlated with the surrounding rock elastic modulus and negatively correlated with the height proportion of broken rock and the burial depth of goaf.The research results provide the theoretical basis and technical support for solving the technical problems that are difficult to balance mining efficiency and environmental protection.