Back Analysis Of Rock Mechanical Parameters And Numerical Simulation Of Stratum Subsidence At WuTong Manor Coal Mine

Based on the engineering background in WuTong manor coal mine of FengFeng miner bureau, a numerical model of mining was set up by ROCKModel software and a orthogonal design-numerical back analysis method of determining the mechanical parameters of rock mass was used in numerical simulation, which combined with observation data.(1) By Rock-model software, we can established a subsidence numerical model of dual-grids with interface for FLAC3D, which can simulate the whole caving process with deformation and failure of coal probability. The numerical simulation result s and the measured data have a good coupling, indicating that the numerical simulation prediction of surface subsidence is an cost saving method.(2) An effective method of determining the mechanical parameters of rock mass used in numerical simulation is given, which employs the orthogonal test method combined with observation data. According to the experimental result, the optimized inversion parameters are obtained by range analysis and variance analysis. Specifically, after orthogonal experiments were designed and numerical simulation, single factor range analysis can show the test index's variation law with increase of the parameter. The variance analysis method is used to analyze the influence degree of mechanical parameters of the test index, which is called the parameter's significant. The obtained parameters are used to calculate by FLAC3D and the results agree well with the in-situ measurement data.(3) Different mining schemes were compared in subsidence numerical simulation so as to put forward rational mining suggestions for the safety of the dam of YueCheng water reservoir. Mining schemes analysis showed that the third scheme can be a best choice.