高坝坝基防渗帷幕结构优化研究 Study on Optimization of Anti-Seepage Curtain Structure for High Dam Foundation

Abstract

针对实际工程坝基防渗处理措施中灌浆帷幕的结构设计，既满足安全性又满足经济性问题，本文基于粒子群算法与有限元方法相结合计算满足约束条件下防渗帷幕的平均深度与等效厚度。以某高坝深厚覆盖层上的混凝土面板堆石坝为案例，首先分析二维模型中无防渗帷幕时坝基渗流场情况，得出无防渗帷幕时坝基透水率相对较高，容易产生渗透破环，因此必须在基岩中进行灌浆以降低坝基渗流量。研究发现：粒子群算法在帷幕结构优化中的可行性和适用性，得出随着迭代次数的增加，粒子不断向最优解靠近，目标函数(工程造价)随着迭代次数的增大逐渐减小并趋于平缓，该研究成果可用于对工程中帷幕灌浆的结构设计提供参考。 The design of grouting curtain in seepage control measures of the dam foundation of the actual project not only meets the safety, but also meets the economic problems. In this paper, based on the combination of particle swarm optimization and finite element method, the average depth and equivalent thickness of impervious curtain under the constraint condition were calculated for concrete face rock fill dam on deep overburden. Firstly, the seepage field of the dam foundation in the 2D model was analyzed, and the permeability of the dam foundation is relatively high when it has no curtain, and it is easy to produce osmotic rupture. It is therefore necessary to perform grouting in the bedrock to reduce dam foundation seepage. The particle swarm optimization (PSO) is feasible and applicable in the optimization of curtain structures. It is concluded that as the number of iterations increases, the particles are close to the optimal solution, and the objective function (engineering cost) is gradually reduced and tends to be gentle as the number of iterations increases. The research results can be used to provide reference for the structural design of curtain grouting in engineering.