高强度开采条件下上行开采顶板运动规律研究

Research on roof movement law of upward mining under high intensity mining conditions

以新疆龟兹矿井2个近距离煤层为工程背景,研究上部煤层工作面在非上行开采和上行开采之间过渡转化过程中,工作面顶板运动的变化规律。将上部煤层工作面开采过程按工作面位置分为“进采空区上方前”、“位于采空区上方”和“出采空区上方后”,结合工程条件设计了3组相似模拟试验进行分析研究。研究结果表明:①上部煤层工作面在位于非采空区上方区域时,其开采过程中顶板运动与一般生产工作面无显著差别;②上部煤层工作面位于采空区上方时,工作面顶板破坏程度加大,发生整体切落失稳;③在上行开采与非上行开采阶段的过渡区域时,顶板稳定性差,且存在前后差异,较大程度上增加了围岩控制难度。研究结果可为上行工作面开采时掌握围岩稳定性变化情况提供依据。

Taking two closely distance coal seams in a certain mine in Xinjiang as the engineering background,the changes in roof movement of the upper coal seam working face during the transition process between non upward mining and upward mining were investigated.By dividing the mining process of the upper coal seam working face into"before entering the goaf","above the goaf",and"after exiting the goaf"based on the position of the working face,three sets of similar simulation tests were designed and analyzed in combination with engineering conditions.The research results indicated that:①When the upper coal seam working face was located above the non goaf area,there was no significant difference in roof movement between its mining process and the general production working face.②When the upper coal seam working face was located above the goaf,the degree of roof damage increased and overall cutting instability occured.③In the transition area between upward and non upward mining stages,the stability of the roof was poor and there were differences before and after,which greatly increased the difficulty of surrounding rock control.The research results provided a basis for understanding the stability changes of surrounding rock during upward mining of working faces.