化学环境下的应力-渗流耦合对尾 矿库稳定性影响试验

通过扫描电镜（FE-SEM）、能谱分析（EDX）、X射线衍射（XRD）、LMS-30激光粒度分析等室内试验探究了尾矿库内存在的酸、碱离子对尾矿颗粒的沉降、微观形貌、物质组成以及粒径级配的影响；建立酸、碱影响下的孔隙比与渗透系数的数学关系模型，并将建立的模型用来表征尾矿库内的应力渗-流场两场耦合机制，实现代入有限元计算软件的目的。结果表明:化学因素的存在影响着尾矿颗粒的多项性状，酸性环境下尾矿颗粒发生溶蚀，部分金属元素流失；碱性环境下尾矿颗粒间生成胶结物质，孔隙出现以含氢氧化铁为主的絮状、团簇状堵塞物，改变了渗流速度；尾矿库内浸润线高度在碱性、中性、酸性环境下依次降低，而渗流速度依次升高。

Experimental study on effect of stress-seepage coupling on stability of tailing pond under chemical environment

The effect of acid and alkali ions in the tailing pond on the sedimentation, microstructure, material composition and particle size gradation of tailings particles were investigated by the laboratory tests such as scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), X-ray diffraction (XRD) and LMS-30 laser particle size analysis. A mathematical relationship model of void ratio and permeability coefficient under the influence of acid and alkali was established, and the model was used to characterize the coupling mechanism of stress field and seepage field in the tailing pond, so as to realize the purpose of substituting into the finite element calculation software. The results showed that the existence of chemical factors affected multiple characteristics of tailings particles. In the acidic environment, the tailings particles were corroded and partial metal elements were lost. While in the alkaline environment, the cementing material was produced between the tailings particles, and the flocculent and cluster stemming mainly containing the ferric hydroxide appeared in the pore, which changed the seepage velocity. The height of phreatic line in the tailing pond decreased in the alkaline, neutral and acidic environment in turn, while the seepage velocity increased in turn.