覆土厚度和边坡形态对排土场边坡稳定性的影响

Influence of Soil Cover Thickness and Slope Geometry on the Stability of Mine Waste Dump

复垦排土场边坡中覆土厚度和边坡形态严重影响矿山排土场边坡的稳定性及复垦效果。以国家电力投资集团内蒙古公司南露天矿排土场边坡为研究对象,利用数值模拟并结合现场监测研究了覆土厚度、台阶高度和坡面角对于边坡稳定性的影响。研究表明,排土场覆土厚度越厚,台阶坡面角越大,以及台阶高度越高,排土场边坡稳定性越差;在保证边坡整体形态不变且满足复垦施工工艺的要求下,将单级台阶坡面改为多级台阶坡面,可提高整体边坡的稳定性;综合考虑排土场复垦效果、容量、施工作业安全以及复垦成本等因素,建议台阶高度为20 m,局部台阶坡面角为24°~28°,最终边坡角为26°,覆土厚度为0.5 m。研究结果对于复垦排土场边坡设计与施工具有一定的指导意义。

The soil cover thickness and the slope geometry have a great effect on the slope stability of the reclaimed waste dump.The slope stability at southern open-pit mine of State Power Investment Corporation Inner Mongolia Energy Co.,Ltd was taken as the case to study the influence of soil cover thickness,the bench height and the bench angle on the slope stability by numerical simulation and field monitoring.The research shows that the thicker the soil cover on the waste dump,the larger the bench angle and the higher the bench height,the worse the slope stability of the waste dump.The slope stability can be improved by changing the single-bench slope to multi-bench slope while keeping slope geometry unchanged and meeting the requirements of reclamation construction technology.Comprehensively considering factors such as the reclaimed effect of dump slope,the capacity,the safety of the construction operation and reclamation cost,it is recommended to set the bench angle of 24°-28°,the final slope angle of 26°and the soil cover thickness of 0.5 m.The research results have a certain guiding significance for the design and construction of slope in reclaimed waste dumps.