Research On Surface Subsidence Control Under Overburden Grouting Of Qinan Coal Mining

In order to secure underground mining coal,reduce the surface subsidence,protect the mining environment,using a variety of different mining technical measures at home and abroad for mary years,the strip mining and goaf water filling gangue and wind filling are most commonly used and effective.Overburden grouting is a new technique of surface subsidence control,the basic principle is to use rock formed in the rock movement during separation from the ground to the layout of drilling hole,hole filling material to support the separation of foreign rock,thus slowing the overburden movement spread to the surface.Overburden grouting and filling the goaf is different:the filling zone in the goaf in the upper strata,the production work won't interfere with filling of underground working face.However,the overburden grouting subsidence control principle remains to be further studied,and the overburden subsidence control engineering grouting is also less.Therefore,this thesis uses the theory deduction,experimental simulation and engineering practice to research on overburden grouting subsidencereduction mechanism in common.The paper selects Huaibei mining area of Qinan Coal Mine of a mining face as the research object,the village is situated above the working face coal seam cut side,belong to "cut the local side pressure coal,control of filling grouting and grouting with different width of the termination time of the past,coal mining face up to 3.5m,for the control of injection production the matching is extremely harsh,the typical features in Huaibei mining area are for the first time.Firstly,from the theory of mining overburden layer development and felling of sirmilar naterial physical experiment and numerical simulation based on the combination of overburden grouting filling process was simulated,revealing the mining overburden grouting surface subsidence control mechanism.Finally,combined with the theory,experiment and engineering,three methods were used to evaluate the effect of surface subsidence reduction.used to evaluate the effect of surface subsidence reduction.The implementation of overburden grouting after grouting,reducing settlement rate reached 96%,the measured maximum horizontal deformation value is only 0.5mm/m,far less than the "grade mining rules provisions under three" the damage to the level of deformation critical value 2.0mm/m,without any damage to the buildings on the ground,to achieve a safe mining purpose,achieved technology,economy and society significant benefits.