基于Ottosen本构关系的混凝土三维损伤模型

Three Dimensional Damage Model of Concrete Based on Ottosen's Constitutive Relations

提出基于混凝土已有本构模型建立混凝土三维损伤模型的方法,该方法无需再进行新的参数标定,计算损伤不必通过对损伤演化方程的积分获得。基于Ottosen本构模型建立了相应的损伤模型,就损伤参量和Ottosen非线性指标的不同选取方式,对典型比例加载情形的全过程进行损伤分析,发现基于刚度下降和基于变形能力损失的两种不同损伤描述具有互补性,非线性指标采用比例增大法计算较为简单合理。

A new scheme was presented, through which the three dimensional damage model of concrete with an known constitutive model can be established. When this model is applied, no new parameter demarcation tests are required, and the damage can be calculated without integration of damage evolution equations. A damage model was developed by using Ottosen's constitutive model. Damage analyses were derived on the whole process of typical proportional loading for different definitions of damage indexes and non-linearity indexes. Two different definitions of damage, based on stiffness decline and loss of residual deformation capacity respectively, show the reciprocity in damage description. The non-linearity index of proportional increment was found simpler and more reasonable.