【摘要】 为了探讨侧压系数对动载诱发特厚煤层巷道底板冲击的影响,使用岩体力学和FLAC2D有限差分数值模拟软件研究了不同侧压系数作用下应力波诱发特厚煤层巷道底板冲击的动态响应规律及显现过程。研究表明,动力扰动的作用是使处于极限应力下的煤体应力增加并打破平衡状态从而诱发底板冲击;动载作用下,随着侧压系数的增加巷道底板的临界水平应力值和最大应力差呈线性增加,底板最大垂直位移在2.0期间呈非线性增加,在2.0后出现微降,说明底板失稳难易程度与底板冲击显现强度不完全呈正相关;底板冲击的显现过程是底板的水平应力瞬间达到临界水平应力,底板塑性破坏区域扩大,致使弹性能瞬间释放,最终导致底板垂直位移发生突然增大产生冲击。研究成果为探索底板冲击机理及防治提供借鉴。更多还原

【Abstract】 In order to reveal the influence of lateral pressure coefficients on floor burst induced by dynamic disturbance,dynamic response rules and burst process of floor in extra-thick coal seam induced by dynamic disturbance at different lateral pressure coefficients were studied by using the rock mechanics and FLAC2D finite difference numerical software.The results show that the ultimate stress equilibrium in floor can be disturbed by dynamic loads so that floor burst is induced.With the increase of the lateral pressure coefficients,critical horizontal stress and maximum stress difference of floor will increase linearly,maximum vertical displacement of floor will increase nonlinearly if 2.0and then decrease slightly as 2.0under dynamic loads.These indicate that instability difficult degree is not positively correlated with burst strength for floor completely.The floor burst process is: 1) horizontal stresses reaches critical value instantly,2) plastic area extends,3) elastic energy releases rapidly,4) vertical displacement of floor increase suddenly,5) the floor burst occurs.The conclusions will provide reference for the study on mechanism of floor burst and its prevention in the same conditions.更多还原