基于降雨对某尾矿坝稳定性影响的研究

发布时间：2018-02-21 16:39

本文关键词： 尾矿坝降雨入渗安全系数数值模拟　出处：《南华大学》2014年硕士论文　论文类型：学位论文

【摘要】：目前对尾矿坝的研究主要集中于尾矿坝的设计施工或者管理方面，，关于降雨对尾矿坝的影响的研究少之又少。然而尾矿坝的溃坝大多数都是在降雨期间发生的，所以研究降雨入渗对尾矿坝稳定性的影响意义深远。降雨入渗增加了坝体的饱和度，基质吸力下降，使其抗剪强度大大下降，当降水达到一定程度，坝体可能失稳破坏，最终可能导致溃坝。本文的主要研究内容及成果如下： (1)本文根据一个具体的尾矿坝，用ABAQUS模拟了降雨244860和72小时后的不同时刻的尾矿坝的孔压位移应力渗流速度以及体积含水率的变化。模拟结果表明随着降雨的进行坝体上部孔压增大，基质吸力下降，坝体表面吸力下降，表层的孔压此时暂态饱和。坝体的位移随着坝高的增大而增大，在x方向的位移发生在浅层。随着降雨的进行坝体的有效应力不断降低，特别是坝体所受的剪力开始下降，后来有所回升，但是幅度很小。在坝坡面上应力变化随着降雨进行而增加。应变发生最大的地方在坝址处。从坝体的表层到深处，含水率整体上是上升趋势。坝体中的水分由坝体的面层向内部迁移，由坝顶向坝脚迁移。模拟结果可以很好的指导施工和设计工作。 (2)在暴雨工况下尾矿坝的安全受到了影响，ABAQUS给出的安全系数为1.15，此时超出了它的临界值1，此时尾矿坝需要进行一些措施来排水。 (3)根据尾矿坝的勘探资料来和实际进行的数值模拟的尾矿坝的孔压和位移随时间变化的规律进行对比，来验证模拟结构的可靠性。选取了三个点来进行模拟，结果表明数值模拟的结果和尾矿坝勘探资料的结果吻合，表明模拟结果可以运用于实践，成功预测了降雨的变化规律。
[Abstract]:At present, the research on tailings dam is mainly focused on the design, construction or management of the tailings dam, and the research on the effect of rainfall on the tailings dam is rare. However, the dam break of tailings dam mostly occurs during the rainfall period. Therefore, it is significant to study the influence of rainfall infiltration on the stability of tailings dam. Rainfall infiltration increases the saturation of the dam body, decreases the matrix suction, and greatly reduces its shear strength. When the precipitation reaches a certain degree, the dam body may lose stability and destroy. The main contents and results of this paper are as follows:. 1) according to a concrete tailings dam, the rainfall is simulated by ABAQUS. 48? 60 and 72 hours after the tailings dam at different times of pore pressure? Displacement? Stress? The simulation results show that with the increase of the pore pressure in the upper part of the dam, the suction of the matrix decreases and the suction on the surface of the dam decreases. The displacement of the dam body increases with the increase of the height of the dam, and the displacement in the x direction occurs in the shallow layer. The effective stress of the dam body decreases continuously with the rainfall, especially the shear force of the dam body begins to decrease. The stress changes on the slope of the dam increase with the rainfall. The largest strain occurs at the dam site. From the surface to the depth of the dam body, The moisture content in the dam body is moving from the surface layer to the inner layer and from the top of the dam to the dam foot. The simulation results can guide the construction and design work well. 2) the safety of tailings dam is affected under heavy rain condition. The safety factor given by Abaqus is 1.15, which exceeds its critical value 1. At this time, some measures are needed to drain the tailings dam. According to the exploration data of the tailings dam, the reliability of the simulated structure is verified by comparing the pore pressure and displacement of the tailings dam with the actual numerical simulation. The results show that the results of numerical simulation are in agreement with the data of tailings dam exploration, and the simulation results can be applied to practice, and the variation of rainfall can be predicted successfully.
【学位授予单位】：南华大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TV649;TV223

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