Wang Gang, Liu Xiqi, Song Leibo, Ma Xiaoming, Chen Wenzhao, Qiao Jiaxing
Collaborative Innovation Center for Prevention and Control of Mountain Geological Hazards of Zhejiang Province, Shaoxing University, Shaoxing, 312000, China.
Huahui Engineering Design Group Co., Ltd, Shaoxing, 312000, China.
Sci Rep. 2023 Jan 18;13(1):981. doi: 10.1038/s41598-022-26130-0.
The tailings pond is a dangerous source of man-made debris flow with high potential energy. The oxidative acidification of tailings may cause the instability of the pond and induce serious safety accidents. The influence of oxidation and acidification degree on macro mechanical properties of tailings is discussed from the aspects of mineral composition and microstructure. The results show that as the degree of oxidation and acidification of tailings sand increases, the overall structural performance and load-bearing capacity decrease, and its cohesion (c) and internal friction angle (φ) show a decreasing trend. In fact, the engineering properties of tailings with different oxidation and acidification degrees are dominated by the physicochemical composition and structural characteristics. On the one hand, as the degree of oxidation increases, acidic substance will neutralize with CaCO and CaMg(CO), resulting in the loss of cemented substance and the decrease of cementation force between tailing sand particles as well as the gradual destruction of the integrity of tailing sand. On the other hand, the increase of oxidation and acidification degree of tailing sand leads to a gradual reduction of outline (2D) fractal dimension and gray surface (3D) fractal dimension of surface laminated structure as well as the obvious reduction of laminated structure and its roughness of tailings sand.
尾矿库是具有高势能的危险人造泥石流源。尾矿的氧化酸化可能导致尾矿库不稳定并引发严重安全事故。从矿物组成和微观结构方面探讨了氧化酸化程度对尾矿宏观力学性能的影响。结果表明，随着尾矿砂氧化酸化程度的增加，其整体结构性能和承载能力降低，其内聚力（c）和内摩擦角（φ）呈下降趋势。实际上，不同氧化酸化程度尾矿的工程性质受物理化学组成和结构特征主导。一方面，随着氧化程度增加，酸性物质会与CaCO和CaMg(CO)中和，导致胶结物质流失，尾矿砂颗粒间胶结力降低，尾矿砂完整性逐渐遭到破坏。另一方面，尾矿砂氧化酸化程度增加导致表面层状结构的轮廓（二维）分形维数和灰度表面（三维）分形维数逐渐减小，尾矿砂层状结构及其粗糙度明显降低。
