基于相变状态的砂土本构模型的研究  

PHASE TRANSFORMATION STATE BASED CONSTITUTIVE MODEL FOR SANDS

作　　者：张卫华[1] 赵成刚[1] 傅方[1] 

机构地区：[1]北京交通大学土木建筑工程学院,北京100044

出　　处：《工程地质学报》2013年第3期337-344,共8页Journal of Engineering Geology

摘　　要：为了很好地描述砂土的应力应变特征,通常利用以临界状态孔隙比为基础的状态参数建立弹塑性本构关系,但是对于密砂排水试验,临界状态参数很难测到。相变状态作为一特征状态,相关参数较容易测得。因此,本文定义了以相变状态孔隙比为基础的状态参数,并引入砂土的剪胀和边界应力比表达式,建立砂土的弹塑性本构模型。最后,利用本文提出的模型参数得到的密砂模拟结果与试验结果相吻合,较好地反映了密砂的应变强化和软化力学特征。To describe well the stress-stain behaviour of sands, generally, a state parameter is used. It is based on the critical state void to established the elastoplastic constitutive relations. However, it is difficult to obtain the crit- ical state parameter in triaxial drained tests for dense sands. The phase transformation state is a characteristic state. Its related parameters are easy to measure. So this paper defines the state parameter that is based on the phase transformation state void. It introduces the stress ration expressions for dilatancy and boundary, and establishes the elastoplastic constitutive model for sands. Finally, based onthe provided model parameters, the simulated results fit well with the test results and realistically reflect the strain hardening and softening characteristics for dense sands.

关 键 词：砂土 相变状态 状态参量 剪胀 本构模型 

分 类 号：TU47[建筑科学—结构工程]