关键词: 大倾角煤层, 非均布载荷, 覆岩结构, 破坏准则, 矿压显现

Abstract: Aiming at the mechanical features of stope in steeply inclined seam, the clamped beam model of roof subjected to non-uniform load is established, the stress characteristics of roof are obtained and the strata-pressure behavior in mining steeply inclined seam are analyzed in association with the motion features of overlying strata along the tilt direction. The results show that the maximum of compressive stress in steeply inclined stope locates the lower surface of the lower beam and its value is about 36% larger than the upper. The maximum tensile stress locates the upper surface of upper beam and its value is 26% larger than the lower. The non-uniform stress of beam and the rock characteristics of higher compressive resistance but lower tensile strength lead early failure in the upper roof and cause roof weighting. Considering the early failure of upper beam and dip angle of coal seam, the work face can be divided into solid filling zone, non-uniform filling zone and dynamic load zone. The structure of overlying strata in solid filling zone is mainly long cantilever beam supported by caved gangue, and its weighting intensity is the smallest of all zones. The dynamic load zone shows short cantilever beam structure, and the load of supports is usually smaller but larger at roof weighting, which shows obvious features of dynamic load. The monitoring results of supports’ working resistance verified the rationality of mechanical analysis of roof and the hypothesis about strata movement along inclination.