大型铝土排泥库混凝土坝动力计算模型及地震响应分析

Analysis of Dynamic Calculation Model and Seismic Response of Concrete Dam of Large Bauxite Tailings Reservoir

混凝土重力坝是桂西大型铝土排泥库的主要坝型,本文建立了考虑坝库作用的排泥库混凝土坝地震动力响应计算模型,采用ADINA有限元软件对比分析了排泥库坝库作用模型与附加质量模型动力计算结果,并揭示了尾矿泥浆含水量和排放量对混凝土坝动力响应的影响规律.结果表明,采用坝库作用模型计算得到的排泥库混凝土坝加速度和位移峰值较附加质量模型要小,更接近实际地震作用情况;上游坝面加速度和位移峰值均沿坝面高程方向增加,最大值出现在坝顶;坝顶位移峰值随尾矿泥浆含水量下降呈近似线性规律减小,含水量在80%~120%范围内下降时,峰值降幅约为含水量处于120%~200%时的2倍;坝体加速度和位移峰值随尾矿泥浆排放量增加而增大,当尾矿泥浆堆排高度大于0.8倍坝高时,坝顶位移峰值增幅变大.研究成果可为类似排泥库混凝土坝动力稳定性分析提供技术支持.

The concrete gravity damwas the main type of the large bauxite tailings reservoir in western Guangxi,a seismic dynamic response calculation model of concrete dam considering the dam-reservoir interaction was established.The dynamic calculation results of the dam-reservoir interaction model and additional mass model of tailings reservoir were compared by the finite element software of ADINA,and the influence of the water content and discharge of tailings slurry on the dynamic response of concrete dam was revealed.The result shows that the acceleration and displacement peaks of concrete dam calculated by the dam-reservoir interaction model are smaller than the additional mass model and closer to the actual earthquake action.The acceleration and displacement peaks of the upstream dam surface increase along the dam surface elevation,and the maximum value appears at the dam crest.The peak displacement of dam crest decreases with the water content of tailings slurry decreases,and when the water content decreases in the range of 80%~120%,the decreasing amplitude is about twice as much as when the water content is in the range of 120%~200%.The acceleration and displacement peaks of concrete dam increase with the increase of tailings slurry discharge,and the decreasing amplitude of peak displacement of dam crest is larger greatly when the stack height of tailing slurry is greater than 0.8 times the dam height.The research results can provide technical support for the dynamic stability analysis of concrete dams in similar tailings reservoir.