针对煤矿底板破坏深度影响因素较多,难以准确地确定难题,通过分析影响底板岩体变形程度的底板岩层的抗破坏能力和作用在底板上的矿山压力两方面因素,选取采深、采高、斜长(工作面)、倾角、底板岩性组合与顶板岩性组合6个因素进行底板破坏深度研究,以某矿4602工作面为背景概化工程地质模型进行6因素5水平正交数值模拟试验。试验结果表明,(1)影响底板破坏深度的主要因素是斜长,顶板岩性组合、底板岩性组合、采深、采高依次减弱,倾角最差;(2)首次明确了顶板岩性组合是影响底板破坏深度的关键因素;(3)建立了斜长-顶底板岩性组合-采深-采高-倾角的采动底板破坏深度预测模型,计算结果较开采规程经验公式的计算结果更接近实际,精度高、误差小,基本可以满足工程使用。研究结果对底板破坏深度的研究以及工程应用具有积极的指导意义。
In response to the problem of more influence factors and difficulties in identifying the depth of damage floor of coal seam, six factors including mining depth, mining height, incline section length (working face), dip angle, floor lithological combination and roof lithological combination were selected to research the depth of damage floor by analyzing two aspects influential elements of the deformation degree of the floor rock, geological model was generalized and six factors and five levels orthogonal numerical simulation experiment were carried out with mine 4602 working face as the background. The experimental results showed that: (1) The main factors influencing the depth of damage floor were incline section length, floor lithological combination, roof lithological combination, mining depth and mining height were weakened in order, dip angle was weakest; (2) that roof lithological combination was the key factors in influencing the floor damage depth was made clear for the first time; (3) prediction model of mining depth of damage floor on incline section length - floor and roof lithological combination - mining depth - mining height - dip angle was established, the calculation results were more close to reality comparing with the results of mining regulation empirical formula calculation, and the precision was high, the error was low, and it can meet the engineering use basically. The results of the study had a positive guiding significance on the research of the depth of damage floor and engineering application.