为了减轻山谷型尾矿库溃坝形成的高流速、强冲击力的尾砂泥石流对下游生命财产造成的损伤,设计以拱型为基础坝型的多级拦截坝,在此基础上构建三维数值模型,对尾矿库多级拦截坝滞留尾砂泥石流效果和对下游敏感目标防护作用开展深入研究.研究结果表明:尾矿库溃坝后形成的尾砂泥石流经多级拦截坝拦挡缓冲后,尾砂在拦截坝处滞留历程分为"爬升、回淤、攀越"3 个阶段,最大流动速度减少约8.86 m/s、砂流到达村庄的最大水位高程时间推迟约 210 s,下游村庄最大淹没水深降低约3.47 m,平均淤砂深度减小近1.87 m,设计的多级拦截坝滞砂防护效果显著.研究结果可为溃坝泥石流多级拦截坝安全防护问题提供借鉴.
In order to reduce the damage to downstream life and property caused by tailings debris flow with high velocity and strong impact caused by dam-break of valley tailings pond,the multi-stage interception dam based on arch dam was designed.On this basis,a three-dimensional numerical model was constructed,and the effect of multi-stage interception dam in tailings pond on the tailings debris flow retention and its protective effect on the downstream sensitive targets were studied in depth.The results show that after the block and buffer of multi-stage interception dam on the tailings debris flow formed after dam-break of tailings pond,the detention process of tailings at the interception dam can be divided into three stages:"climbing,re-turning and ascending".The maximum flow speed is reduced by about 8.86 m/s,the maximum water level elevation of the sand flow to the village is delayed by about 210 s,the maximum submerged depth of the downstream village is reduced by about 3.47 m,and the average silting depth is reduced by nearly 1.87 m.The designed multi-stage interception dam has a re-markable sand retention and protection effect.The research results can provide reference for the safety protection of multi-stage interception dam for dam-break debris flow.