高浓缩分级尾矿上游法堆坝及模型试验研究

Model tests on upstream dam-building method using concentrated and classified tailings

针对传统上游法尾矿库堆坝方法的缺陷与不足,提出了改进的上游法堆坝方法,即高浓缩分级尾矿上游法堆坝方法。基于尾矿库堆坝模型试验,以高浓缩尾矿堆存技术为指导,分别进行传统上游法和改进上游法的高浓缩尾矿堆坝模型试验,演绎尾矿库堆坝过程,测试并得出了堆坝过程中滩面尾矿沉积情况、尾矿颗粒分布规律及浸润线变化规律,并采用极限平衡法计算不同堆坝方式下坝体的最小安全系数。结果显示：高浓缩尾矿堆坝使沉积滩颗粒分布均匀,颗粒分级不明显,减少了互层和细泥夹层的出现,改善了坝体内部结构;改进上游法堆坝可以形成有利于排渗防洪的良好沉积滩滩型;稳定性分析结果表明,改进上游法堆坝方法可以使尾矿坝的稳定性提高19%~33%,研究成果可为新建尾矿库工程提供试验技术支撑。

To overcome the disadvantages of the traditional upstream dam-building method, an improved tailings dam-building method, i.e., upstream dam-building method using concentrated and classified tailings, is proposed. Based on the tailings dam model tests, and guided by the concentrated tailings technique, model tests of both the traditional and improved upstream dam-building methods were performed. Through these tests, the deposition condition and particle distribution of tailing materials were examined, and the variation of saturation line on dry slope was determined. The limit equilibrium method is used to calculate the minimum safety factors for different dam building methods. It is shown that： the building dam with highly concentrated tailings can lead to even particle distribution and obscure the particle classification, while reducing the inter-bed and fine-mud sandwiches in the sedimentary area; the improving upstream dam-building method favors the formation of a sedimentation type, which is good for drainage and flood control; the stability Of tailing dam can be improved by 19% to 33% if the improved upstream dam-building method is adopted.