基于MIDAS的尾矿边坡三维流固耦合稳定性分析

Analysis of three-dimensional fluid-solid coupling stability in tailings slope based on MIDAS

针对尾矿坝边坡稳定性问题,使用三维有限元软件计算,对吉林省集安石墨尾矿坝进行渗流-应力-边坡耦合分析。渗流分析基于三维介质达西定律,通过不断改进工况条件来降低浸润线溢出部位,保证坝体不会发生渗透破坏。同时,尽量降低溢出部位的应力坡降,保证坝体不会发生流砂、管涌等形式渗透破坏。在渗流计算的基础上,进行渗流-应力-边坡耦合,不断改进尾矿边坡的坡角和高度等要素,得到强度折减法下的尾矿边坡稳定性系数。通过理论计算和验证,提出了一种便于施工的排渗体布置方式,并验证了排渗体的可靠性,为尾矿坝具体施工提供了技术支持。

Aiming at the stability of tailings dam slope, the seepage-stress-slope coupling analysis of Ji an graphite tailings dam of Jilin province is carried out using three-dimensional finite element calculation software. The seepage analysis is based on Darcy's law of three-dimensional medium. The overflow position of the saturation line is reduced by continuously improving the working conditions to ensure that no seepage damage happen to the dam body. The stress gradient at the spillover site should be reduced as far as possible at the same time. Therefore, the dam body will not suffer seepage damage in the form of quicksand and piping. On the basis of seepage calculation, the stability coefficient of tailings slope under strength reduction method is obtained by seepage-stress-slope coupling and continuous improvement of slope angle and height of tailings slope, etc. Through theoretical calculation and verification, a layout method of drainage body for construction is put forward, and the reliability of drainage body is verified. It can provide technical support for the concrete construction of tailings dam.