A COMPREHENSIVE METHODOLOGY FOR PREDICTING SHIELD SUPPORT HAZARDS FOR A U.S. COAL MINE

Abstract

ABSTRACT: Shield support hazard prediction is important for the safety and productivity of an underground coal mine. Hence, research should be conducted on shield support hazard prediction. Thus, this study presents a comprehensive methodology for predicting shield support hazards in a virgin mining area. A total of 33 surface boreholes were drilled to cover the general mining area. All analyses were based on the extensive strength and physical properties of strata above and below coal seam B, including coal seam B itself. The modified detached roof block model was used to determine support roof load capacity, and the roof load isopach maps for three mining heights were drawn to show the load distribution for different mining heights. A regression equation was used to obtain the maximum floor pressure, and the isopach map showed the value difference between rock mass strength and floor pressure distribution. To clarify the geological discontinuities and immediate roof type variation trend, a fence diagram was drawn, and the corresponding responses were discussed. By combining the roof load capacity, floor pressure, and geological discontinuities, shield support hazards were clearly illustrated by a hazard map. The proposed methodology can predict the potential shield support hazards and identify areas where supplementary support can be implemented, thereby enabling mining engineers to incorporate the roof load capacity, floor pressure, and geological discontinuities effectively into an integrated hazards prediction map for use in support design and supplementary support strategies.