【摘要】 厚煤层沿底布置巷道顶板维护难度较大,从爆破扰动影响顶板稳定性的角度对此进行了研究。在分析爆破应力波远区破坏效应的基础上,建立了沿底布置巷道顶板的剪切梁模型,依此研究了顶板煤、岩体的水平位移及应力分布规律,最后以某矿地质条件为原型利用Flac3D数值软件进行了模拟研究。研究发现:基于爆破应力波的远区破坏效应,沿底布置巷道的顶板煤层与上覆岩层的相对错动可以用剪切梁理论加以分析。基于此得到了厚煤层巷道顶板中煤层与岩层单调加载过程及循环加载条件下的位移及应力分布,单次爆破对顶板的影响有限,多次扰动的累积效应会对其产生一定程度的损伤。模拟中,随着装药量的增加,沿底布置巷道顶板煤、岩体的水平位移随之增加,且煤体的位移量大于岩体;持续扰动条件下,煤、岩体的水平位移均出现了累加效应,且随着动力扰动作用次数的增加,煤、岩体的相对错动逐渐增大,容易产生顶板离层垮落等动力灾害。研究成果对加强扰动作用下顶板的支护管理具有一定的理论与指导意义。更多还原

【Abstract】 Maintenance of the roadway roof arranging along the bottom of the thick coal seam is difficult,in this paper,the study has conducted from the point of view of blasting disturbance which affects the roof stability.On the basis of analzing the damage effects of blasting stress wave far zone,a model about arranging shear beam of the roadway roof along the bottom of coal seam was established,and the horizontal displacement of the coal and rock mass in the roof and distribution of the stress through the model was studied.Finally,Flac3D numerical software was used to conduct simulation study by taking the geological conditions of a mine as the prototype.The results showed that: based on the damage effects of blasting stress wave far zone,the shear beam theory can be applied to analyze relative diastrophism between roof seam of the roadway arranging along the bottom of the coal and overlying strata.Based on this,the displacement and stress distribution of seam and rock in roadway roof of thick coal seam under monotonic loading process and cyclic loading conditions can be determined.Single blasting has a limited impact on the roof,and the cumulative effect of multiple disturbances have a certain degree of damage.In the simulation,with the increase of the amount of gunpowder,the horizontal displacement of coal and rock mass increases along with the bottom of seam arrange the roadway roof,and the displacement of coal is more than that of rock mass.In the condition of persistent disturbances,the horizontal displacement of coal and rock mass shows an additive effect,the relative diastrophism of coal and rock mass increase with the increase in the number of dynamic disturbance,which is liable to dynamic disasters like collapse of roof abscission layer.The research result shows a certain theoretical and directive significance of strengthening the management of roof support under disturbance.更多还原