一种土层非线性本构模型参数的确定方法

提出一种合理确定土层非线性弹性本构模型参数的方法.以现今普遍实行的地基载荷试验为基础,依据遗传算法的组合优化理论,采用正演计算和遗传算法优化相结合的方式,建立了土层非线性弹性本构模型参数的确定方法;并依据某黄土场地地基载荷试验数据,实施了黄土土层非线性弹性本构模型参数确定的全过程.计算结果表明,所建立的方法可以实现土层非线性弹性本构模型中相互关联的多个参数的组合优化,并在对初始值要求较低的情况下,可以获得良好的参数反演精度.从而为土的变形特性分析和土与其中及相邻结构的共同作用分析,提供了较好的土体本构模型参数的确定方法.

Parameters Determination on Nonlinear Constitutive Model of Soil Stratum

Aiming at presenting a method to difine reasonably the parameters of nonlinear elastic constitutive model of loess stratum.according to the coincident optimization theory of the genetic algorithm,on the basis of foundation load experiment, which is now put into practice generally, the parameter determination method on the nonlinear elastic constitutive model of soil is established by means of combining forward computation and the back analysis of the genetic optimization algorithm. Meanwhile, using the data from foundation load experiment of loess stratum, the progress of the parameter determination on the nonlinear elastic constitutive model of loess stratum is implemented. The results show that this method can accomplish the coincident optimization of much relative parameters in the nonlinear elastic constitutive model of soil and does give good estimation without imposing stringent requirement on initial values of the parameters. Therefore, for analyzing the deformation characteristics and the interaction characteristic of soil and the structure which is in soil or adjacent to soil,our work provide a good method for determining the model parameter of soil.