邓肯—张E-B模型参数对心墙土变形的敏感性研究

有限单元法是一种常见的分析岩土结构变形的数值计算方法,其土体模型参数的准确性是计算结果高可靠性的保证.邓肯—张E-B模型是坝体变形分析计算中常用的一种非线性弹性模型.以一心墙坝为例,针对模型参数的敏感性进行大量的非线性有限元计算,计算结果表明:影响心墙土变形的主要参数为K,Rf和φ,n对心墙土变形的敏感性较低.随着K和φ的增大,心墙土竖向位移减小；随着Rf增大,竖向位移增大.从整体来看,邓肯-张参数对竖向位移的敏感性要大于对有效应力的敏感性.

Sensibility Analyses of the Duncan-Chang E-B Model Parameters to Deformation of Core Wall Soil

Soil model parameters are critical in assuring reliability of numerical results of commonly used finite element method for simulating deformation of geological structure.The Duncan-Chang E-B model,a nonlinear elastic model widely used in the geological engineering,is chosen in this paper.One core dam is used as an example for the sensibility analysis.The results show that the main parameters influencing the deformation of core wall soil are K,Rf and φ,n shows weak sensibility relatively.The increase of K and φ can result in an decrease in the vertical displacement and the increase of Rf can result in the increase of the vertical displacement.On the whole,the sensibility of the Duncan-Chang model parameters to the displacement is greater than the sensibility to the effective stress of the soil.