顺层岩质边坡加陡开采的稳定性研究

Researches on Stability of Rock Bedded Slopes under Steep Slope Mining

为了研究确定顺层边坡陡帮开采的稳定性,以元宝山露天矿南帮边坡为研究对象,基于刚体极限平衡理论,采用RFPA中的细观本构模型,研究分析南帮边坡受采动影响应力和位移随时间的变化规律,分析滑坡机理、滑坡模式,并确定最终境界的合理边坡角。结果表明:采用细观模型得到的岩体变形随时间的变化规律与现场观测基本吻合,上部岩体沿圆弧滑面拉裂滑移,下部沿弱层组合滑面剪切滑移,且滑体上部均以下沉为主,向采空区发生水平位移,下部以水平位移为主。计算剖面边坡的稳定系数Fs<1.2,应放缓边坡角使(?)=18°以保证边坡稳定使露天矿安全生产并获得最大效益。

In order to determine the stability of rock bedded slopes under steep slope mining , the changing rule of the stress and deformation speed of slope with time, the effects of deformation were analyzed based on the rigid body limit equilibrium theory and the constitutive model of RFPA in the Yuanbaoshan South Slope Mine. With the landslide model the ultimate realm of the reasonable slope angle was determined. The results show that the deformation of slope agrees with the actual observational result. The upper surface of rock is sliding along the circular having crack slip. And the lower is along the weak layer combination shear slip, with horizontal displacement. Profile of the slope stability factor is calculated to be Fs 〈 1.2. The reasonable slope angle should be controlled to 18° ,in order to ensure the open-pit slope stability and get the most safety benefits.