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The dust control basis of fully mechanized mining face is clear dust source characteristics. In view of the problem of unclear dust source and unknown distribution characteristics in the working area of 7.8 m large fully mechanized mining face, the fully mechanized mining face of Shendong Bulianta Coal Mine is selected as the The research object adopts the method of combining numerical simulation and field measurement to study the dust migration law based on the single action and joint action of the two main dust sources of shearer cutting coal and column moving frame, and obtains the dust migration law. According to the characteristics, the distribution of respirable dust concentration in the breathing zone of personnel in the vicinity of the shearer was further analyzed. The results show that the dust produced by dropping the column and moving the frame has the greatest impact on the dust concentration in the operator’s area. The maximum value of the respirable dust concentration in the operator’s area when cutting coal downwind and upwind is in the middle of the shearer, and originates from the shearer cutting coal. The proportions of dust source and column-moving dust source were 44.50% and 76.69%, respectively. The dust traceability research can provide a theoretical basis for the targeted management of dust in fully mechanized mining face with large mining height.

According to the characteristics of the 1-2 coal seam of Shangwan coal mine 4th panel, this research analyzed the feasibility of sublevel caving hydraulic support in the fully-mechanized mining face through estimation method and numerical simulation calculation. This paper also researched the several factors that affect the caving property of top-coal, such as coal thickness, coal hosting depth, top-coal joint fissure, parting condition and caving height. In the meantime, the FLAC3D was used to simulate the caving progress. The results showed that the scheme is feasible. This method cannot only guarantee the stability of coal wall but also crush the coal by the force from the mine pressure hydraulic supports.