Research On Backfill Mining Technology And Overburden Stability Evaluation Of Deep Coal Seam

With the rapid development of economy in our country, the traditional energy resources of coal mining in our country as a scale increasing, the recoverable resources is decreasing, three times(under buildings, railways, water) and dull coal can not get reasonable mining, it become mining area sustainable and stable development of mining and mining production of important issues. In addition, the mine production of waste rock pile up on the ground commonly, make land resources being used, and after a long period of weathering, cause environmental pollution. Taking the waste rock filling mining method, which can realize recycling, and can be used as underground structure to support the body, so as to control the surface subsidence, improve the coal recovery rate, protect the ecological environment of mining area, the liberation of the "three under" coal resources, etc. In view of this, this paper takes shaanxi his long buried deep seam filling mining is a mine project, the integrated use of theoretical analysis and numerical simulation of two kinds of research methods, on the basis of analyzing the reasonable mining method and filling process, the deep coal gangue filling technology and overburden stability evaluation for research, has certain value of research results have been achieved. Main conclusions are as follows:(1)Through the analysis of the room and pillar mining, strip mining, pillar mining and pillar mining of the advantages and disadvantages and applicability. Considering the applicability, stability and economy of the three factors identified, determining the mining zone for deep buried coal seam in the optimal way. Through the reasonable arrangement of mining operations and filling operation sequence, layout reasonable filling mining technology and mining transportation system layout, filling of the transport system and the specific transport operation method is presented in this paper. Finally, to determine compliance with the actual situation of gangue filling landfill waste process, analysis of the impact of gangue backfilling effect factors, and puts forward the improving gangue filling effect and of filled with waste rock filling technology measures.(2)According to the strip mining layout, reasonable roadway and coal pillar size, research and analysis of the coal pillar width of roadway stope arrangement, width of coal pillar laneway, the mutual influence between roadway coal pillar and the number of isolated coal pillar width and other parameters of the relationship, calculate the lane between the safety coefficient of coal pillar and isolated coal pillar width and the safety coefficient of mining; interval above the pressure arch stability analysis, the pressure arch arch and arch foot is the key to stability, calculation of arch arch foot safety coefficient and safety coefficient; according to the strip mining arrangement formula of mining rate and filling rate, and calculate the 28 kinds of filling roadway and coal pillar layout mining rate and rate under different filling coefficient. Finally, according to the roadway width, lane width of coal pillar and number, isolated coal pillar width, stability of coal pillar pressure arch stability and recovery rate and filling rate etc. parameters of 28 kinds of layout scheme of selection, it is recommended to meet the reasonable scheme of stability and economy. Finally in Binchang mining area buried deep coal pillar filling technology supporting of stope of coal pillar mining design of supporting parameters, get the corresponding support support parameters.(3)The based on plate theory of deep buried coal seam strip type filling mining surface subsidence prediction, under the premise of stability of overlying strata in the assurance, all pillar mining layout, using FLAC3 D software for backfill mining overlying strata stability simulation, verification of the predicted the correctness of the theory. At the same time, using the software FLAC3 D simulation, comparison and analysis of different filling rate under Lane between the coal column and formation of by force and deformation characteristics, of deep seam backfill mining overlying strata stability evaluation has certain reference value..