基于微平面弹塑性应力-应变关系的混凝土本构模型

Elastic-plastic microplane constitutive model of concrete

在Bazant等提出的混凝土微平面本构模型M2的基础上,将微平面上的应力分解为体、偏、剪三个分量,根据各个分量的物理意义定义了相应的应力-应变关系函数,即理想弹塑性函数。引入破断应变的概念,当微平面应变达到破断应变后应力减为零。介绍了模型参数的确定方法。最后通过三个算例初步验证了所建议模型的合理性和正确性。

A dynamic elastic-plastic microplane constitutive model of concrete, based on M2 model proposed by B. P. Baaant et al. , was presented. The state of each microplane was characterized by normal deviatoric and volumetric strains and shear strain. The strain-stress relations for deviatoric and Shear component were described as elastic-plastic model. A new concept of failure strain was introduced. If strain component on microplane exceeds the failure strain, the stress will be zero. The parameter determination method and its analysis were provided. Three types of test data with respect to concrete in existing literatures were used for fitting with the model reults presented in the paper. The results are in good agreement which shows the model is reasonable and accurate.