库水位变动条件下的尾矿库溃坝模型试验研究

针对尾矿坝的溃决模式和尾矿库在库水位变动情况下发生溃坝危险等问题，采用自行设计的尾矿库溃坝模拟试验装置并考虑水位变化情况下，开展了尾矿库室内溃坝模型试验。结果表明：1）在库水位变动条件下，尾矿库发生漫顶溃坝，溃坝过程中，水流侵蚀引起的连续下切加深和溃口边壁发生失稳破坏引起的横向展宽是控制溃口演化的两个重要因素；2）坝体在溃决后发生明显的垂直沉降和水平位移，坝体沉降位移主要发生在坝肩和坝体中上部处，而坝体水平位移主要发生于坝体中下部和坝脚处；3）溃口处坝体下沉位移达到最大，溃口下泄泥沙流颗粒粒径随着距溃口距离的增加而逐渐递减，粒径分级现象由不明显到明显，临界距离为距溃口150 cm处。研究为尾矿库在库水位变动情况下的灾害防治提供较好的指导意义。

Model Test Study on Tailings Dam Break Under the Condition of Reservoir Water Level Fluctuation

Aiming at the failure mode of tailings dam and the danger of dam-breaking of tailings ponds when the reservoir water level fluctuates, based on the self-designed tailings pond dam-break simulation experiment device, the tailings pond under the condition of the fluctuating reservoir water level is developed. Indoor dam-break model experimental research,the research results show that: 1) Under the condition of the fluctuating reservoir water level, the tailings dam will be over-topped and the dam-break will occur. The lateral broadening composition is an important factor leading to the evolution of the breach; 2) The dam body undergoes obvious settlement and horizontal displacement after the breach. The settlement displacement of the dam body mainly occurs at the dam abutment and the upper part of the dam body, while the horizontal displacement of the dam body mainly occurs at the middle and lower part of the dam body and the foot of the dam; 3)The subsidence displacement of the dam body at the breach reaches the maximum, and the particle size of the sediment flow under the breach gradually decreases with the increase of the distance from the breach. The particle size classification phenomenon changes from insignificant to obvious, and the critical distance is 150 cm from the breach. This study provides a better guiding significance for the prevention and control of disasters in the tailings pond under the condition of the fluctuation of the reservoir water level.