尾矿坝外坡比对漫顶逐渐溃坝的影响研究

Impact of Tailings Dam Outer Slope Ratio on Overtopping Dam Breach

为了研究尾矿坝外坡比对均质尾矿坝溃坝过程的影响,在概括了溃决过程的基础上,利用了坝坡冲刷计算模型、溃口扩展计算模型,形成了用于探讨尾矿坝外坡比在漫顶逐渐溃坝过程中对坝坡和溃口影响的数值计算方法,并用溃坝案例验证了计算方法的可行性.结果表明,坝体外坡比的大小对均质尾矿坝溃口出流浑水冲蚀下游坝体的规律有明显影响,尾矿坝外坡比越大,溃口扩展越快,其临界起动流速越小,冲蚀率越大,下游坝体受侵蚀破坏的严重程度越大.因此,在尾矿坝施工过程中要严格按照设计的坡比,确保下游坝体具备一定的抵抗冲蚀的能力.

Aimed to study the influence of the outer slope ratio on the overtopping breach of a homogeneous tailings dam,the slope erosion model and breach extended model were adopted,and a numerical calculation method used for researching the impact of the outer slope ratio on dam slopes and breaches in the overtopping gradual dam breach was constructed and the method was validated with instances of dam breaches.The results show that the outer slope ratio has a significant influence on tailings dam breaches.The higher the outer slope ratio is,the faster the breach expands,the smaller the critical incipient velocity is,and the larger the erosion rate is,the greater the severity of erosion on and damage to the downstream dam is.Thus,the designed slope ratio has to be strictly maintained in the construction of a tailings dam to ensure that the downstream dam resists erosion.