基于混沌遗传算法的碾压混凝土坝力学参数反分析

坝体物理力学参数是衡量坝体质量的一项重要指标,如何获取碾压混凝土坝当前实际的物理力学参数是分析和评价大坝安全性态的前提和关键。根据碾压混凝土坝施工过程、压实机理和层面特性等,将碾压混凝土坝力学参数识别反问题作为优化问题处理,系统地研究并建立了碾压混凝土坝变形力学参数反分析理论和方法。为克服传统遗传算法的早熟缺点,在处理优化问题时引入混沌遗传算法,并应用混沌遗传算法对某碾压混凝土坝的横观各向同性变形参数和渐变参数进行了反演。最后将横观各向同性模型与参数渐变模型计算值和实测值进行对比分析,验证了反分析理论和方法的正确性,同时也说明了参数渐变模型的合理性和正确性。

Back Analysis for Mechanical Parameters of Roller Compacted Concrete Dam Based on the Chaos Genetic Algorithms

The physical and mechanical parameters of the dam are an important indicator for measuring the quality of the dam,therefore how to obtain the presently physical and mechanical parameters of the roller compacted concrete dam is important to analyze and evaluate the safety behavior of the dam.In this paper,the inverse problem of the mechanical parameters of the roller compacted concrete dam was treated as the optimization problem based on the study on the construction process,compaction mechanism,and surface characteristics of the dam,and thus the back analysis method and theory to determine the mechanical parameters of the roller compacted concrete dam were established.The chaos genetic algorithms were introduced in dealing with the optimization problem to overcome the precocious shortcomings of the traditional genetic algorithms,and it was applied to inversely analyze the transversely isotropic deformation parameters and gradient parameters of a roller compacted concrete dam.Finally,the simulated and measured parameters for the transversely isotropic model and gradient model were compared and analyzed,which confirmed that the accuracy of the back analysis method and theory and the reasonableness and validity of the gradient parameter model.