基于数值模拟的高压采场卸压方案研究

Pressure Relief Scheme of High-Pressure Stope Based on Numerical Simulation

为了安全开采含有较多采空区的矿体,制定了2种卸压方案,并采用FLAC^(3D)软件对矿体进行建模,模拟并分析了其卸压效果。结果表明,采用方案1(卸压巷道与凿岩巷道呈“非”字形、相邻卸压巷道间隔10 m)时,最小主应力在凿岩巷道两边及顶板附近分别从8 MPa和9 MPa降至5 MPa和8 MPa,最大主应力变化不大;采用方案2(交错式开挖卸压巷道、相邻卸压巷道间隔20 m)时,最小主应力在凿岩巷道与卸压巷道的交汇处从8 MPa降至4 MPa,最大主应力在下层凿岩巷道顶板附近由24 MPa降至20 MPa。模拟结果表明,方案2的卸压效果优于方案1。小厂坝矿区按方案2进行卸压巷道施工,安全地完成了60万吨矿体开采。研究成果对巷道卸压的工程实践具有一定参考价值。

In order to safely mine ore bodies with several goafs,two kinds of pressure relief schemes were prepared,and a model was established for the ore body by using FLAC^(3D) software to simulate and analyze the pressure relief effect.The results show that by adopting the scheme 1(the pressure relief tunnels and the drilling tunnels are arranged in the shape of a fishbone with a spacing of 10 m),the minimum principal stress on both sides of the drilling tunnel and near the roof decreases from 8 MPa and 9 MPa to 5 MPa and 8 MPa,respectively,while the maximum principal stress changes little.And with the scheme 2(the pressure relief tunnels are in a staggered arrangement with a spacing of 20 m),the minimum principal stress at the intersection of drilling tunnel and pressure relief tunnel is reduced from 8 MPa to 4 MPa,and the maximum principal stress near the roof of the lower drilling tunnel is reduced from 24 MPa to 20 MPa.The simulation results show that scheme 2 is superioir to scheme 1 in the pressure relief effect.The application of scheme 2 in the Xiaochangba mining area showed 600,000 tons of ore bodies were safely mined out.It is concluded that this research result is of certain reference for the engineering practice of tunnel pressure relief.