Study On Primary Mineable Coal Seam Thickness Stability And Influence Factors In Xinji No.1Mine

In recent years, many scholars for the mine geological rules, with coefficient of variation of coal seam thickness, coal seam recoverable index as the thickness of coal seam stability evaluation index has been questioned, think that these two indexes is not complete reflects features of the coal seam thickness,so how to determine a more reasonable evaluation system is currently a hot issue. In this paper,taking No.l coal group,No.6-1coal seam,No.8coal seam,No.11-2coal seam and No.13-1coal seam as the research object,from the point of view of sedimentary environment and geological structure, analyze the factors influencing the thickness of coal seam, using fuzzy comprehensive theory and selecting coefficient of variation of coal seam thickness, non-coal mining index,coal gangue thickness coefficient,structural index of four indicators, to make quantitative evaluation on the stability of coal seam thickness.Xinji No.1Mine is the successful model of mining under nappe, this article selects No.13-1coal seam, No.1coal group,to analyse thickness stability influence factors, discuss whether the coal seam thickness stability is affected by the nappe, mainly made the following points:1. No.13-1coal seam has good sedimentary environment, sedimentary basement stability, epigenetic washout have no influence on the thickness of coal seam;but layer slip structure is key factors which influence the stability of coal seam thickness of No.13-1coal seam; Layer slip structure leads to the development of tectonic coal in the minefiled, its development degree is greater than the adjacent not affected by the nappe of Zhang Ji field.2. Middle of No.1coal group is washed almost, all of which were replaced by sandstone layers, upper part of No.1coal group in the southern showing large areas of non-coal erosion area, comprehensive look of the entire minefield, belongs to the unstable coal seam, but look from northern mining field, the stability of coal seams is relatively good; No.1coal seam is located in the lower part of No.1coal group,presents the phenomenon of north south thin thickness,The layer slip structure exacerbated the change of thickness of No.1coal group,but have less effect on the stability of the thickness.