基于能量耗散原理的混凝土力学损伤模型

从材料变形破坏过程中能量耗散特征入手，视混凝土材料为仅有损伤耗能的脆弹性部分和仅有塑性流动耗能的理想弹塑性部分共同组成，基于复合体损伤理论建立了混凝土力学损伤本构模型。对于脆弹性部分，分别采用张拉损伤和压剪损伤两个损伤变量描述不同应力作用下损伤行为，并通过受荷变形过程中的能量守恒原理推导相应的损伤演化方程；对于理想弹塑性部分则采用Mohr-Coulomb条件加以描述；利用FLAC3D软件开发相应的模型计算程序，算例计算结果表明，模型能够较好反映混凝土的力学特性。

Mechanical damage model for concrete based on energy dissipation

The concrete materials are simplified as a complex model which is composed of elastic-brittle part and ideal elastic-plastic part. Based on the process of deformation failure and energy properties, a damage constitutive model is established. To the elastic-brittle part, two damage variables are put forward based on the different mechanism of energy dissipation aroused by tension and compress stress. Through the principle of conversation of energy, corresponding damage evolution equations are established. The yield strength of ideal elastic-plastic material is described by Mohr-Coulomb criterion. Corresponding computer program is developed by the fast Lagrangian analysis of continual (FLAC3D). The results indicate that this model can reflect the mechanical property.