深井破碎围岩巷道变形机理及控制研究

为解决深井破碎围岩巷道的支护问题,针对薛湖煤矿西翼轨道大巷的地质状况,建立了巷道底鼓力学模型,研究巷道围岩的破坏特征及其影响因素,通过分析得出:巷道两帮围岩的破碎起到天然卸压作用,延缓了底鼓的产生,随着帮部岩体的压实,应力继续向底板传递,进而引发了巷道底鼓.据此提出针对深井破碎围岩巷道采用二次支护方法控制围岩变形的方案:即一次支护采用U型钢可缩性支架进行支护、二次支护采用锚注与锚梁网索联合支护,其最大的特点是将传统的滞后注浆改为适时注浆,为锚杆锚固作用的发挥提供支撑平台,提高了支护效率.通过数值模拟优化,确定了最终的支护参数,并进行了现场工业性试验,观测结果表明,巷道变形得到了有效控制,取得了较好的社会经济效益.

Failure Mechanism and Control Measure of Roadway Deformation with Fractured Surrounding Rock in Deep Mine

To solve the support problem of fractured surrounding rock roadway in deep mine,based on the geological conditions of west track haulage roadway in Xuehu coal mine,we established the mechanical model of roadway floor heave,and studied the failure characteristics and influence factors of the surrounding rock in this paper.The results show that the fractured surrounding rocks around two sides of the roadway have natural pressure relief effect which can delay the formation of floor heave.With the compaction of surrounding rocks in the two sides,the stress continues to transfer toward the floor which then initiates the floor heave.Hereby,the secondary support technology is proposed to control the roadway deformation with fractured surrounding rock in deep mine,that is to say,the U-steel yieldable support is adopt as the first support,while the bolt-grouting and bolt-beam-net-anchor cable support are adopt as the second support.The greatest characteristic of the technique is altered from the lagging grouting to timely grouting,which provides a platform for exerting the anchorage effect of bolt,and the support efficiency is improved greatly.The final support parameters are determined by numerical simulation optimization,and have applied to the field industrial test.The observation results show that the roadway deformation is controlled effectively,and has obtained great social and economic benefits.