大型铝土排泥库堆石坝地震动力响应分析

Analysis on Seismic Dynamic Response of Rockfill Dam of a Large Bauxite Tailings Reservoir

排泥库是一种具有高势能的人造泥石流危险源,一旦发生溃坝,将对下游群众生命财产安全造成重大威胁,而地震灾害是尾矿坝事故的第二大元凶。采用ADINA有限元软件建立考虑坝库作用动力响应分析计算模型,探究尾矿泥浆物理性质、排放量和坝体尺寸对排泥库堆石坝的动力响应影响规律。结果表明,坝顶位移峰值随着尾矿泥浆含水量下降呈近似线性降低规律,含水量在120%~80%下降时,位移峰值的降幅明显增大;随着尾矿泥浆排放高度的增加,坝体加速度减小而位移峰值增加,当尾矿泥浆排放液面高于0.4倍坝高时,坝顶位移峰值增幅变大。随着坝体坡比、坝高、坝顶宽度的增加,坝体的加速度峰值减小,位移峰值增加,当坝体高度大于44 m时,坝顶位移峰值增幅明显增大。研究成果可为排泥库堆石坝动力稳定性分析和抗震设计提供理论指导。

Drainage mud is a dangerous source of artificial debris flow with high potential energy. Once a dam break occurs,it will pose a major threat to the safety of life and property of the downstream people,and the earthquake disaster is the second largest culprit of tailings dam accident. In this paper,finite element software ADINA is used to establish a dynamic response analysis model considering dam reservoir action,and to explore the influence of tailings mud physical properties,emissions and dam body size on the dynamic response of the tailings dams. The results show that the peak displacement of the dam crest decreases linearly with the decrease of the water content of the tailings mud. When the water content decreases from 120% to 80%,the drop of the peak displacement increases obviously. With the increase in height of the deposited mud,the acceleration of the dam body decreases and the peak displacement increases. When the filled mud level is higher than 0.4 times the dam height,the peak displacement of the dam crest increases. With the increase of dam slope ratio,dam height and dam crest width,the peak acceleration of the dam body decreases and the peak displacement increases. When the dam height is greater than 44 m,the peak displacement of the dam crest increases significantly. The research results can provide theoretical guidance for the dynamic stability analysis and seismic design of the rockfill dam in mud tailings reservior.