基于应变等效性假说的损伤定义的适用条件

A Variable Condition of The Damage Description Based on Hypothesis of Strain Equivalence

研究了基于应变等效性假说的损伤定义方法，分析了定义中“材料损伤前后弹性模量”的物理含义。指出该方法只适用于间接描述弹（脆）性材料损伤行为，不能简单地用受荷过程中的“卸载模量”代替假说中的“受损弹性模量”来描述具有不可逆塑性变形特征的弹塑性损伤行为，否则将可能导致对损伤行为的误判。此外，本文给出了一种耦合塑性形变和损伤机制影响的弹塑性损伤定义。

This paper discusses the applicability of the damage definition based on Hypothesis of Strain Equivalence. The physical meanings of the modulus of a material before and after damaged are analyzed. It is pointed out that the damage definition based on the hypothesis is only applicable to describe the damage characteristics of elastic (brittle) materials. It cannot be used to determine the damage characteristics of elastoplastic materials by replacing the elastic modulus after damaged with the relaxed modulus of a material. Otherwise, the evaluation for damage behavior of elastoplastic materials may be wrong. Additionally, a damage definition for elastoplastic materials is introduced, in which the mixed influence of the plastic and damage mechanisms is taken into account.