湿堆尾矿双向排水大变形固结计算模型

摘要

根据上游法湿堆尾矿的工艺特点，在分析上游法湿堆尾矿渗流固结特性和存在问题的基础上，结合一种适合于上游法尾矿库的排水固结装置的排水特点，在考虑竖向和径向双向排水、变渗透系数及变荷载条件下，采用大变形固结理论推导了尾矿固结计算模型，进而得到以超静孔隙水压力表示的考虑双向排水作用的大变形固结控制方程，并将该方程与Barron固结方程进行比较，验证了计算模型的正确性。采用有限差分法对该大变形固结控制方程进行求解，得到了固结控制方程的差分方程，并利用追赶法等数学方法对差分方程进行了求解。以中铝广西分公司某尾矿库为计算实例，采用该排水固结装置的大变形固结计算模型及数值计算程序进行计算，结果表明该计算模型能有效反映尾矿的固结规律，采用排水固结装置尾矿固结时间缩短了60%以上。%According to the wet landfill process of upstream tailings, its seepage consolidation characteristics and existing problems are analyzed and additionally, it is put forward based on a drainage device that is suitable for about upstream tailings. With the establishment of the mathematical model, it was possible to derive the formula that considers vertical and radial drainage, varying permeability coefficient, and variable load condition at the same time. The governing equations of large-strain consolidation with both horizontal and vertical drainage are reduced, which is denoted by excess pore water pressure. By comparing study of that governing equations and Barron consolidation formula, we assessed the accuracy of the proposed model. Using the finite difference method to derive the resulting of large strain consolidation of differential equations, thus obtaining the differential equations of consolidation equations an then solving it by using mathematical methods like Pursuit Method. Using the Guangxi Branch of Chalco aluminum tailings as case study, the results show that this calculation model can effectively reflect the consolidation law of the tailings slurry, and the consolidation time of tailings slurry is shortened by more than 60%.