基于剑桥模型的砂土剪胀模型

Dilatant Model of Sand Based on the Cam-Clay Model

对于中密砂和密砂,剪胀现象是一个比较显著的特征,相变线是描述剪胀现象的一条特征线,相变线比较容易确定.本文在已有弹塑性模型基础上,对硬化参数进行修正,并引入与相变线相关的状态参量,建立了一个新的剪胀性砂土本构模型.该模型尤其适合于中密砂和密砂,对于松砂则退化为原弹塑性模型.模型包含9个材料参数,参数比较容易确定.数值模拟结果能较好的描述砂土的主要特性.

Dilatant phenomenon is one of the key features of medium-dense sand and dense sand, and phase transition line can be used to describe this phenomenon. Based on the Cam-Clay model, an elastic-plastic model is proposed. To character the dilatant behavior of sand correctly, a function modifying the hardening parameter is introduced, and a state parameter involving the void ratio of phase transition is suggested. The model includes 9 parameters, which can be easily determined. The principal behaviors of medium dense sand and dense sand have been precisely represented.