排渗失效下尾矿库溃坝三维模型试验研究

针对尾矿库渗透破坏模式，为克服二维试验槽边壁效应对模型渗流走向及溃决位置的影响，本文以某尾矿库为原型，基于自主设计的三维尾矿库溃坝模型试验平台，进行了排渗设施失效诱发的尾矿库溃坝模型试验研究，揭示了该尾矿库的溃决模式及溃决机理。结果表明：(1)排渗失效导致的溃坝呈现局部流土破坏-坝体累计变形-深层滑动面发展贯通-整体突发失稳的渐进伴突发型溃决演化模式;(2)坝体孔隙水压力骤变是坝体发生滑动破坏的关键响应指标，预示着坝体将在短时间内由滑动体前后缘局部散浸软化、流土、塌陷转变为大范围溃决，可作为坝体溃决事故的前兆信息;(3)排渗失效导致的尾矿库溃坝过程具有渐进性和突发性的特点，发生散浸与流土破坏的过程时间较长，发生深层滑动和溃决的时间短暂，该特征可为尾矿库渗透破坏隐患治理及坝体溃决应急响应提供参考。研究结果对尾矿库溃坝的灾害预防具有重要的现实意义。

3D model test study on dam-break of tailings pond under drainage failure

In order to overcome the influence of the 2D test tank edge wall effect on the seepage direction and failure position of the seepage failure mode of tailings pond，a tailings pond is taken as a prototype and conducts a model test study of tailings pond dam break induced by the failure of drainage facilities based on a self-designed 3D tailings pond dam failure model test platform.The failure mode and mechanism of the tailings pond are revealed.The results show that：(1) the dam break caused by drainage failure presents a gradual and sudden outburst evolutionary pattern consisting of local soil flow failure，cumulative deformation of dam body，deep sliding surface development，and overall sudden instability.(2) The significant change in pore water pressure is a key response indicator for seepage failure of the dam body.It indicates that the dam body will transform from part scattered softening，soil flow，and collapse at the front and rear edges of the sliding body to large-scale collapse in a short period of time，and can serve as a precursor to dam break accidents.(3)The process of tailings dam break induced by the failure of drainage facilities has the characteristics of gradual and sudden changes.The process of scattered softening and soil flow failure takes a long time，and the time for deep sliding and collapse is very short，which can provide reference for the treatment of seepage damage hazards and emergency response to dam collapse in tailings ponds.The research results have important practical significance for the prediction and control of tailings dam failures.