一种对初始值要求较低的土层参数识别方法

提出了一种土的非线性弹性本构模型参数识别的方法。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识别的方法;并依据某黄土场地地基载荷试验数据,实施了黄土地层非线性弹性本构模型参数识别的全过程。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识别精度。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。

A Promising Parameter Identification Method of Soil Using Foundation Load Experimental Data

Aim.We aim to identify the nonlinear elastic constitutive model parameters of soil by fully utilizing the foundation load experimental data.In the full paper,we explain our promising parameter identification method and its effectiveness in some detail;in this abstract,we just add some pertinent remarks to naming the first three sections.Section 1 is:the nonlinear elastic constitutive model expressed in terms of stresses.Section 2 is:developing the parameter identification method for nonlinear elastic constitutive model.Section 3 is:the implementation of the parameter identifacation method and its effectiveness.In section 1,we use the tangential elastic constitutive model as shown in eq.(6) to calculate the stress and deformation of soil.In section 2,we combine the forward computation with the genetic algorithm to calculate the values of displacements and the adaptability degree.The flow chart of the computation is given in Fig.1.In section 3,using the foundation load experimental data from loess stratum,we implement the parameter identification for nonlinear elastic constitutive model.The numerical calculation results and their comparison,given in Tables 1 through 3 in the full paper,show preliminarily that our method can optimize multiple inter-related parameters in the nonlinear elastic constitutive model of soil and enhance the parameter identification accuracy without imposing stringent requirements for initial values of parameter.