采空区覆盖层对顶板大规模冒落冲击灾害的防治研究

Study of the prevention and control of large-scale impact disaster caused by roof caving with goaf overburden

顶板垮冒是地下采空区事故发生的重要危险源之一。为研究顶板大范围冒落产生的空气冲击灾害及覆盖层的防护作用,以敦德铁锌矿采空区为工程背景,采用理论分析、数值模拟等综合研究方法,根据现场实际开采条件对采空区空气冲击灾害进行理论计算,结合流体力学数值软件对采空区顶板冒落进行模拟分析。研究结果表明:数值模拟可以较好表现出不同工况下空气冲击风流在采空区内的扩散行为。无覆盖层时,空气冲击风流在出矿巷道内的最大风速可达482.6 m/s,最大动压可达602142 Pa;有30 m覆盖层时,出矿巷道内的最大风速仅为2.71 m/s,最大动压仅为8.03 Pa,在实际生产中采取相应防护措施可以有效保护人员和设备的安全。

Roof caving is one of the important hazard sources of underground goaf accidents.In order to study the air impact disaster caused by large-scale roof caving and the protective effect of overburden,taking the goaf of Dunde iron-zinc mine as the engineering background,using comprehensive research methods such as theoretical analysis and numerical simulation,the air impact disaster in goaf is theoretically calculated according to the actual mining conditions on site,and the roof caving in goaf is simulated and analyzed in combination with fluid mechanics numerical software.The results show that the numerical simulation can better show the diffusion behavior of air impact airflow in goaf under different working conditions.When there is no ore overburden,the maximum wind speed and maximum dynamic pressure of impact air flow in the ore-drawing roadway can reach 482.6 m/s and 602142 Pa;when there is a 30-meter-thick ore overburden,the maximum wind speed in the ore-drawing roadway is only 2.71 m/s and the maximum dynamic pressure is only 8.03 Pa.In actual production,it is recommended to reserve a sufficient thickness of ore overburden to effectively protect the safety of personnel and equipment.