冻融循环对露天矿不同类型边坡的影响研究

Influence of Freeze-thaw Cycle on Different Types of Slope in Open-pit Mine

复杂的地质构造使得露天矿往往存在多种类型边坡,为使冻融条件下露天矿边坡的治理评价更具针对性,采用MIDAS数值模拟结合室内试验的方法,研究冻融循环对青海木里某露天矿2种类型边坡稳定性的影响程度;通过室内冻融循环试验发现岩石黏聚力、弹性模量随冻融循环次数的增加而明显降低,而内摩擦角基本无变化;数值模拟结果表明:冻融循环使露天矿南帮顺倾边坡安全系数从1.13下降到1.01,破坏方式从坡顶剪出破坏转变为坡面顺层滑动破坏;而对北帮反倾边坡基本无影响;研究成果对该区域露天矿边坡的治理评价工程具有一定的借鉴参考意义。

The complex geological structure makes the open-pit mine often have many types of slopes.In order to make the evaluation of open-pit mine slope under freezing and thawing conditions more targeted,MIDAS numerical simulation combined with laboratory test method is used to study the influence of freezing and thawing cycle on the stability of two types of slopes in an open-pit mine in Muli,Qinghai.In the indoor freeze-thaw cycle test,the cohesion and elastic modulus of rock decrease significantly with the increase of freeze-thaw cycles,while the internal friction angle basically does not change.The numerical simulation results show that the freezing-thawing cycle reduces the safety factor of the south slope of the open-pit mine from 1.13 to 1.01,and the failure mode changes from the shear failure of the slope top to the bedding sliding failure of the slope surface.and it has no effect on the anti-dip slope of the northern slope;the research results have certain reference significance for the treatment and evaluation project of open pit slope in this area.