The horizontal distance X between roadway and the edge of its upper pillar is considered as an important parameter for layout of roadway in floor strata or in the adjacent coal seam. Based on the research achievements of rockstrata pressure, this paper illustrates the quantitative relationship among the mining situation of upper seam, the roekstrata properties around roadway, the vertical distance Z (between roadway and its upper pillar), and the horizontal distance X (between roadway and the edge of its upper pillar), and provides a main basis for the selection of value X and the relative location between roadway and its upper seam.
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