基于改进人工鱼群算法的碾压混凝土坝粘弹性参数反演

摘要

为合理模拟碾压混凝土坝自身流变特点,择取适当模型作为坝体和坝基材料持载变形下本构关系,建立有限元方程,使大坝变形与其物理力学参数的隐性对应关系明确化.在实测大坝位移变形资料的基础上,运用统计模型提取各所需位移分量,建立优化反演目标函数,采用相对于基本人工鱼群算法(AFSA)全局优化能力更加高效精准地改进人工鱼群算法(IAFSA)对碾压混凝土坝粘弹性力学参数进行搜索反演,并对二者的寻优结果做出对比分析,IAFSA算法的优越性得到证实.反演求解计算过程通过对改进人工鱼群算法的程序化语言设计结合ANSYS有限元计算命令的调用来实现.文末工程实例计算数据成果证明,本文反演方法可应用于坝工结构反分析领域.%To simulate the rheological properties of roller compacted concrete dam (RCCD),generalized Kelvin model is selected to describe the constitutive relation of dam material;and then a finite element computing model is buiso that the relationship between dam displacement and its viscoelastic mechanics parameters is figured out.Based on measured data,using statistical model to separate out the water pressure component and aging component,the objective function is buiand the improved artificial fish school algorithm(IAFSA),which has more efficient and accurate ability of global optimization compared with the artificial fish school algorithm(AFSA),is adopted to the inversion of viscoelastic mechanics parameters.The optimization results of contrastive analysis prove the superiority of IAFSA.The process of inversion is realized by VB programming design for IAFSA combined with calling the calculation command of ANSYS.The achievements of the engineering project at the end of the text prove that the inversion method can be applied to back analysis field of dam structure.