Similar simulation on strata movement of fully-mechanized caving mining in thick coal seam with thick dirt band

Aimed at improving the performance of the fully mechanized caving mining technology,as in the case of structurally complex coal seams,this paper,based on similarity simulation experiment,investigates movement characteristics of thick dirt band,top coal,and roof rock with structurally complex thick coal seam subjected to fully mechanized caving mining. Research shows that: thick coal seam with thick dirt band shows a more sublevel caving; position with significantly increased displacement gets much closer to the coal wall; and the top coal breaking is subjected more to thickness of dirt band,so that,in the case of dirt band of a certain thickness,sublevel caving is found to occur with little or no effect. Mining simulation observation analysis is basically consistent with measured data analysis. This study may provide a reference for the safe and efficient expansion of sublevel caving mining area.