恒底开采矿压显现规律模拟研究

本文在现场实测的基础上,利用相似材料模拟实验方法,对厚煤层恒底开采和下行分层开采的矿压显现规律进行了对比研宄。研究结果表明:恒底开采第一分层时,由于顶煤易在采空区冒落,冒高较大,因此老顶来压时对采场的影响程度明显减小,这对于厚煤层坚硬顶板条件下的安全生产是十分有利的;恒底开采时,顶板裂隙扩展范围较小(裂隙带高度减小),并能减小顶板出现离层的高度,因此,有利于顶板含水层下(或地表水下)安全生产;恒底开采时,除最后一个分层外,各分层工作面的顶板均为煤体,因此可以减少煤炭含矸率,当煤层顶板较破碎时,其效果更明显

SIMULATION STUDY OF MINING PRESSURE MANIFESTATION FOR COAL MINING TAKEN IN ASCENDING ORDER

Based on the field study, comparisons are made for the manifestation of the mining pressure between coal mining taken in ascending order and mining taken in descending order in thick coal seams by using the similar material simulation method in this paper. Main results of study shows that because the top coal can cave easily in the gob and the casing height is large, when first slice is mined alone the bottom, the effect of main roof weighting to the working face decreases considerably, it is conducive to safe production when the roof of thick coal seam is very hard, The height of the fractured zone of the roof and the height of roof separation decrease when coal mining taken in ascending order, it is conducive to safe production under the roof strata which are water-saturated layers. The roofs of all slices except the last one are coal when coal mining is taken in ascending order, it can reduce the coal dilution. Especially for the condition of hrittle roof strata.