深部破碎硬岩采动压力分布规律与控制方法研究

为研究深部破碎硬岩采动压力分布规律,以弓长岭井下铁矿为工程背景,采用收敛监测的方法,对3个不同采深的采场进行采动压力监测。监测结果表明:弓长岭井下铁矿采动压力变化呈波动趋势,最大采动压力出现在采空区边界8 m左右的位置;采动压力的峰值在空区边界上盘方向3 m到下盘方向10 m左右的范围内;沿矿体走向方向,采动压力的影响范围超过11.5 m,距回采工作面8.5～11.5 m范围内存在较大采动压力;采空区旁侧采动压力辅助监测得到采动压力峰值距采空区边界6.2～9.3 m的范围内,验证了最大采动压力出现在采空区边界8 m左右的结果。在此基础上,提出了锚网喷浆联合支护方案,预计该方案能够很好地解决弓长岭井下铁矿深部矿岩采动压力显现问题,达到预期的支护效果。

Mining Pressure Distribution Law and Control Method in Deep Broken Hard Rock

In order to figure the mining pressure distribution law in deep crushed hard rock， and with Gongchangling iron mine as engineering background， mining convergence monitoring is made in three stopes with different depths. The monitoring results show that the mining pressure in Gongchangling shows a fluctuating trend with the maximum mining pressure appearing at about 8 m away from the boundary of the gob. The peak of mining pressure appears within 3 m above the hanging wall and 10 m below the foot wall. The influence scope of the pressure exceeds 11.5 m along the direction of the ore-body， and the concentrated mining pressure exists in the range of 8.5 to 11.5 m from the working face. The peak mining pressure is within 6.2 to 9.3 m to the boundary by auxiliary side-pressure monitoring， which verifies the maximum mining pressure appearing at about 8 m away from the boundary. On this basis， a bolt-net-grouting joint support scheme is proposed to solve the problem of mining pressure in deep underground and achieve expected supporting effect.