沿空留巷巷旁充填体稳定性控制技术研究

Research on stability control technology of filling body in gob-side entry retaining

充填体稳定性控制是沿空留巷成功的关键因素之一。为获得合理的充填体稳定性控制技术,以三河尖煤矿7136工作面千米深井沿空留巷为工程背景,采用UDEC6.0的Trigon模型校正了巷旁充填体(高水材料水灰比为1.5∶1.0)的数值模型,然后对充填体稳定控制的钢筋梯子梁直径、对拉锚杆直径及数量不同时的充填体应力应变进行了模拟分析。研究结果表明:充填体的加固作用可有效约束充填体表面位移,综合提升充填体的承载能力可达20%以上,提高了沿空留巷充填体的稳定性,特别是增加对拉锚杆直径和数量在大变形的条件下可有效控制充填体帮部的整体横向变形和鼓包现象,是提高充填体加固系统护表能力、充填体承载能力的重要参数之一。研究成果成功应用于千米深井沿空留巷,加固后的充填体帮平均变形不超过150mm,顶板下沉量不超过250mm,表明充填体加固系统可靠,而且具有良好的适应性。

The stability control of filling body is one of the key factors for the success of gob-side entry retaining.In order to obtain a reasonable filling body stability control technology,the paper took the No.7136 working face of Sanhejian Coal Mine as the engineering background,and used UDEC6.0 to correct the numerical modal of the filling body(water cement ratio of high water material was 1.5∶1.0).Then the diameter of reinforcing steel ladder beam and pulling anchor rod were controlled by filling body stability.The stress and strain of filling body with different diameters and quantity were simulated and analyzed.The results showed that the reinforcement effect of filling body can effectively restrain the surface displacement of filling body,comprehensively enhance the bearing capacity of filling body up to 20%,improve the stability of filling body along gob-side retaining roadway,especially increase the diameter and quantity of tension bolt under the condition of large deformation,which can effectively control the overall transverse of filling body side.Deformation and bulging is one of the important parameters to improve the surface protection capacity and bearing capacity of the filling reinforcement system.The research results have been successfully applied to the gob-side entry retaining in a kilometer deep well.The average deformation of the backfill wall after reinforcement was not more than 150 mm,and the roof subsidence was not more than 250 mm.It showed that the backfill reinforcement system was reliable and had good adaptability.