露天石灰石矿山岩质边坡坡角优化设计研究

Optimization Design for Rock Slope Angle in Open-pit Limestone Mine

基于赤平投影图解法、极限平衡法以及数值模拟方法,提出了提高矿山开采量的思路:先统计分析矿山边坡的优势结构面,然后基于数值模拟软件3DEC,模拟计算在优势结构面组合的影响下其局部台阶边坡的稳定性,优化并得到局部台阶边坡在优势结构面组合的影响下能保持稳定状态的优化边坡角。最后,基于极限平衡理论,利用Slide对边坡角优化设计方案进行稳定性验算,并求得边坡在自然工况、爆破工况、地震工况下的稳定性系数,以提高设计方案的安全储备,最终提高矿产资源的开采量。以四川省兴联矿区的石灰石边坡为研究对象验证了该方法的可行性,结果表明,考虑优势结构面最不利组合对边坡稳定性的影响时,计算得出的最优边坡角为50°,相比于此前设计的边坡角45°提高了5°,从而提高了矿山的开采量。本文提出的边坡角优化思路可以提高矿山开采效率和经济效益。

Based on stereographic projection method,lim it equilibrium method and numerical sim ulation,an idea was proposed for improving exploitation.F irstly,data statistics and analysis were performed to obtain the dominant structural plane.Then,based on the numerical simulation software,3DEC,the stability ol the partial terraced slope influenced by a combination of the dominant structural plane was calculated by sim ulation,and an optimized slope angle was obtained for the terraced slope to keep stable under such combination effect.F inally,based on the lim it equilibrium theory,Slide software was adopted to check the slope stability of such slope angle optimization design,and the stability coefficient for the slope under natural working conditions,blasting condition and earthquake condition was obtained,respectively,which could improve the safety of the design program,thus increasing the mineral exploitation.W ith a limestone slope in Xinglian mine area in Sichuan Province as the object in the study,the feasibility of this method was verified.The optimal slope angle was calculated to be 50°,with the consideration of the slop stability influenced by the most unfavorable combination of dominant structural plane,compared to the angle of 45°in the previous design,up by 5°.Consequently,the quantity of exploitation in the mine was improved.It is concluded that the idea of optimizing slope angle proposed in the paper can bring both mining efficiency and economic benefits to the mine.