| The safe mining can be realized by using the filling mining technology, which can improve the rate of coal resources recovery and protect the ecological environment of the mining area. This paper mainly of overlying strata movement and mining fissure are summarized based on the evolution theory and calculation, according to the basic parameters of rock mechanics test results of Wanbei Wugou coal mine CT101 working face of the different filling rates of filling mining of FLAC3D numerical simulation, analyzes the overlying rock fissure development height and the rock mass surrounding the stopes should stress mining with the vary filling rates. And comprehensive analysis of the measured results of the CT101 working face. Hope to provide some reference for the safe and efficient recovery of the filling working face under the similar conditions. The detailed research contents are as follows:(1) The theory and model of filling mining. Based on the elastic foundation beam, the simplified model is introduced and the model is analyzed, and the mathematical relationship between the filling ratio and the height of the overlying strata is established.(2) In this chapter, the basic geological conditions of the 10 coal CT101 filling mining working face in five ditch coal mines are the basic basis, and the results of the test results of the rock foundation parameters are obtained. On this basis, the numerical simulation and analysis of the full rate of 50%,65%,80%,90% conditions of the plastic zone, the surrounding rock displacement field, the stress field distribution evolution law.(3) Filling mining practice of CT101 working face in five ditch coal mine. After is described in the above chapters, in the fourth chapter of the thesis introduces the five ditch coal mine CT101 work surface and filling mining practice, analysis of mine pressure behavior and the development results of mining induced fracture, and the second chapter is the theoretical analysis from the mining fissure height and in the third chapter, the numerical simulation results are compared and concluded.In this paper, through the above research, that filling mining does not exist in the traditional sense of "three zones", only in the presence of local caving area, with increase of the filling rate, the movement of overlying strata deformation more relaxed, the fracture height was significantly lower in:under the condition of the filling mining, filling working face overburden exists only tiny fault subsidence zone and without caving zone, and the descent with only will spread distance stope which is near to the lower strata. Numerical simulation results show that under the condition of the filling mining, enrich rate reached 80% and 90% after, overburden rock plastic zone development in a tiny range. Only in the coal seam roof above 10m, vertical displacement of overburden significantly decreased, the maximum subsidence is only 290mm-580mm rock should be stress level decreased significantly, the surrounding rock stress concentration coefficient is only 1.22～1.32, and working face advance abutment pressure influence range is less than 7m. Five ditch coal mine CT101 working face mining goaf in full rate is 89% under the condition of that form of overlying strata movement for unstable fracture, settlement, contacting waste and cycle pressure is not obvious, mine pressure appear more relaxed, also by fissure water with highly developed close to 10m, high degree of coincidence with numerical simulation, impacts on surface settlement is very small, the project can be neglected. |
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