采矿动压对采场巷道稳定性影响的研究

Study on Impact of Mining Dynamic Pressure on Stability of Drifts

用无底柱分段崩落法开采处于不良工程地质(破碎、高地压)条件下的矿体时,采场巷道稳定性一直是制约生产发展的重大技术难题。在影响采场巷道稳定性的诸多因素中,除工程地质因素外,采矿动压也是一个非常重要的因素。以程潮铁矿为工程背景,采用现场应力应变监测和数值模拟等研究方法,分析了矿体退采、爆破震动和下盘围岩空间形态等采矿动压因素对无底柱分段崩落法下盘地压的影响,弄清了采场巷道地压规律、影响范围和峰值出现的位置。提出了采场巷道避免采矿动压影响的措施:改变和避开应力集中区、预加强支护和减少分段最大药量等,同时,对采准设计给出了一些建设性的意见。多年的实践表明,合理布置采准巷道,巷道能服务到本水平开采结束。

The stability has been a major technical challenge restricting the production development when sublevel caving is used in the exploitation of orebodies under bad engineering geological conditions（fractured, high ground pressure ）. Among the many factors that affect the mining drift stability, mining dynamic pressure is a very important one except engineering geological ones, With Chengchao Irnn Mine as the engineering background and using the methods of local strainstress monitoring and numerical simulation, the impact of mining dynamic pressure factors such as orebody extraction, blast vibration and underlying host rock shape on the underlying ground pressure in sublevel caving was studied, and the ground pressure law of mining drifts, its influencing sphere and the location of peak value were found out, Measures for the drifts to avoid the impact of mining dynamic pressure were proposed, including changing and avoiding the stress-intensified area, pre-reinforcing the support and reducing the maximum charge of explosive in sublevels, and meanwhile some constructive suggestions were given on the development design. The many years＇practice shows that with a rational allocation of development way, the drifts can provide service until the end of the mining activity of this level.