考虑分布结构的土体本构模型

Constitutive model for soils based on the concept of disturbing structure

为反映土体分布结构对其变形特性的影响,提出土体分布结构概念,对修正剑桥模型进行了扩展;认为塑性变形的内变量不是单一、固定值,而是在一定区间上遵循统计分布密度函数分布;从而将修正剑桥模型单一尺寸的单个屈服面扩展至尺寸连续的无穷连续屈服面,并建立了一个能描述土体逐渐屈服的本构模型。模型参数有4个,其中3个参数与修正剑桥模型的参数相同,新增了一个参数反映土体分布结构特征。初步验证表明模型能够反映土体逐渐屈服的变形特征。

Based on the concept of disturbing structure,this paper presents a progressive yield constitutive model by extending the Cam-Clay model in order to describe influence of the disturbing structure on soil behavior.The internal variable of yield surface is not just a constant parameter,and it should be treated as a distribution function in a range.The single yield surface of the Cam-Clay model wis extended to a field of yield surface.Then by introducing the progressive yield concept into the Cam-Clay model,the progressive yield constitutive model wis developed.Only one parameter wis added besides the three parameters of the Cam-Clay,which represents the disturbing structure of the soils.The application results show that the model can predict the progressive yield of the soils.