我国很多煤矿巷道受到临近陷落柱或地质构造影响.针对常村煤矿陷落柱附近-470南翼辅助运输巷底鼓严重的问题,根据弹塑性理论和Hoek-Brown准则,建立了陷落柱周围塑性破坏区力学模型,推导出陷落柱影响区巷道加固段长度计算公式.基于X射线衍射实验和朗肯土压力理论分析了陷落柱区巷道底鼓机理,提出了"适当加密锚杆+大直径高强锚索+钢筋网喷层+滞后高压注浆"的锚网喷注综合控制方案,并对其支护机理进行分析.工程实践表明,加固段长度的理论计算误差约为9.3%,巷道加强支护后底鼓量比原方案大约减小了70%~75%,实现了陷落柱影响区大断面膨胀性软岩巷道底鼓的有效控制.
Many roadways are affected by the nearby collapse column or geological structure in China's coal mine. In order to solve the serious floor heave problem of No. -470 south auxilia- ry transportation roadway nearby the collapse column in Changcun coalmine, a mechanical model of plastic failure zone around collapse column has been proposed according to elastic- plastic mechanics and Hoek-Brown criterion. In addition, a theoretical reinforced supporting length formula was also derived. The floor heave mechanism of roadway near collapse column was analyzed based on X-Ray diffraction experiment and Rankine' s earth pressure theory. Then the integrated supporting scheme of "reasonable bolt spacing +high-strength anchor ca- ble + mesh reinforcement spray concrete + delayed high pressure grouting" was put forward based on the analysis of supporting mechanism. Field test results show that the relative devia- tion of theoretical reinforced supporting length is 9. 3% and the floor heave decreased by 70%-75% after using the integrated supporting scheme. The serious floor heave of large sec-tion soft rock roadway influenced by collapse column can be effectively controlled.