Research And Application Of Gob Side Entry Retaining Technology Based On Deformation Mechanism Of Roadside Filling Body

Coal pillar mining method is an important part of green mining technology, which is widely used in the eastern part of China. But there are still many problems need to be further studied, such as the control mechanism of the surrounding rock, the filling of the low cost, the safety of the lane and so on. In this paper, for the gob-side entry method with roadside filling, the deformation mechanism and the technology of the thick coal seam along the goaf are studied systematically through comprehensive utilization of theoretical analysis, orthogonal numerical simulation experiment and field industrial test and other research methods. The paper obtains the following results:(1) The main control factors influencing the stability of the side filling body are obtained through estabilishing the mechanical structure model of the filling body in stope, and it can be divided into working conditions,geometric parameters, rock mechanical parameters and so on. Based on this, it designed and implemented an orthogonal numerical simulation experiment. It analyzed the sensitivity of the main control factors and the damage deformation law of the roadside filling body. Further during the design and implementation of gob-side entry retaining technology several factors should be taken into consideration: the cohesive strength and tensile strength of mining depth and height, filling ratio, mechanical parameters of filling materials, especially special filling width.(2) By analyzing the applicability of the condition of different surrounding rock properties (hard roof and sandstone in the stability of the roof) in the thick coal seam, a mining method with high applicability is put forward according to its conditions: "the supporting method with constant resistance pressure in hard roof'. Besides it has studied the main structure of this technology and expounded the establishment method of its main parameters. Under the favorable conditions of surrounding rock steady sandstone roof, on the premise of of mining safety and low cost of filling, a low cost mining method is proposed for the medium stable surrounding rock that "the interval type filling mining method for medium stable strata". By constructing the mechanical model of the interval between the wall and the rock beam, it analyzed the mechanism of the rock beam and the filling unit and expounded the establishment method of its main parameters.(3) Based on the analysis of the geological and technical conditions of the coal mine, it is determined to take the interval filling mining method in the working face of the coal mine. It designed the filling parameters of working face; the feasibility of the roof is analyzed by using the embedded beam model and the interval filling is considered feasible in this mine.And the proportion of filling material and its filling technology were studied, and the effect was tested by the in-situ rock pressure observation.(4) In filling process in the fields of Fu Kang coal mine, it designed a highly mechanized filling template that "Middle thick coal seam hydraulic fixed Lane side filling" and "Plate type strip filling device in mining". The application of the first kind of application improves the work efficiency of the gob-side entry retaining technology.