大埋深组合顶板巷道围岩支护技术研究

Study on surrounding rock support technology of large buried deep combined roof roadway

深部采准巷道支护问题是当前煤炭资源向深部开采所必须解决的关键问题之一。而深部采准巷道顶板多为复合层状顶板,并受到较大的上覆垂直荷载和水平构造应力的联合作用。通过对复合层状顶板锚固形成的组合岩梁进行受力分析,得出梁下侧的最大拉应力计算公式。根据最大拉应力准则确定出组合岩梁的高度,进而确定锚杆的长度。根据所得结论对关中某煤矿40303工作面采准巷道复合顶板进行参数设计,结果表明,对深部巷道复合层状顶板锚固所形成的组合岩梁能有效承载较大的上覆垂直荷载和水平构造应力,采用该支护方案可有效控制复合顶板的变形,取得较好的支护效果。

The support problem of the deep mining preparation roadway is one of the key problems that must be solved in the current deep mining of coal resources.The roofs of deep mining preparation roadway are mostly composite layered roofs,which are subject to the combined action of large vertical overlying loads and horizontal tectonic stresses.The stress analysis of composite rock beam formed by anchorage of composite layered roof is carried out,and the formula for calculating the maximum tensile stress of the lower side of the beam is obtained.According to the maximum tensile stress criterion,the height of composite rock beam is determined,and then the length of bolt is determined.According to the conclusions obtained,the parameters of composite roof of the mining preparation roadway in 40303 working face of a coal mine in central Shaanxi are designed.The results show that the composite rock beam formed by anchoring the composite layered roof of deep roadway can effectively bear larger vertical load and horizontal tectonic stress,the supporting scheme adopted can effectively control the deformation of surrounding rock of roadway and achieve better supporting effect.