中文摘要：

为了建立一种新的单轴受力下混凝土损伤本构模型,应用损伤力学理论,假设混凝土卸载刚度与初始刚度的比值和混凝土卸载后剩余的弹性应变能与总应变能的比值在数值上是一致的,由此将弹性模量损伤和能量损伤结合为一体,通过数值方法可确定混凝土单轴受力损伤变量的具体数值。在已有不同强度等级混凝土单轴受力的应力-应变全曲线统一计算方法的基础上,通过数值积分和拟合回归,建立了单轴应力状态下混凝土损伤演变方程和损伤本构模型。结果表明：该模型可描述混凝土单轴循环加载受力状态下的力学特性,与混凝土单轴受力试验结果吻合较好;该研究成果可望进一步应用于反复加载下混凝土结构非线性有限元分析中。

英文摘要：

Applying the theory of damage mechanics, supposing the numerical values between the ratio of unloading elastic modulus to the initial elastic modulus and the ratio of residual elastic strain energy after unloading to the total strain energy are equivalent, this paper presents a new damage constitutive model for concrete under uniaxial stress conditions. Thus the elastic modulus damage is combined with energy damage, and the numerical value of damage variable of concrete under uniaxial stress conditions is determined by numerical method. Based on the unified calculation method of stress-strain relationship of various strength of concrete under uniaxial stress conditions, through numerical integration and regression analysis, the evolvement law of damage and damage constitutive model for concrete under uniaxial stress conditions are proposed. The results show that the model can describe the response of concrete under uniaxial cyclic loading. It is indicated that the analysis results of the damage constitutive are in good agreement with the experiment ones. This work is a base for the further researches on the nonlinear element analysis of concrete structures under reversed cyclic loading. 2 tabs, 4 figs, 12 refs.