损伤弹性材料的有效模量及本构关系

考虑了微裂纹之间的相互作用，利用随机熔断丝网络（Ｒａｎｄｏｍｆｕｓｅｎｅｔｗｏｒｋ）作为模型，模拟了脆性材料在外载荷作用下，其有效模量随损伤的演变行为，并考察了系统含损伤的本构关系。发现在损伤初期，有效模量和损伤具有线性下降关系；而在后期，由于损伤局部化，有效模量迅速下降，提出了一个有效模量随损伤变化的非线性关系。讨论了利用网络模型来研究材料含损伤本构关系的可行性和优越性。

EFFECTIVE MODULI AND CONSTITUTIVE RELATION OF DAMAGED MATERIALS

In this paper, considering the interaction of microcracks, Using the random fuse network model. the computer simulation evolution behaviour of effective moduli of damaged brittle material during the damage process under applied loading is made.The constitutive relation of the corresponding system is also investigated. It is found that at the early stage of damage. the effective moduli decreases linearly with the increase of damage; while at the later stage,the effective moduli decreases rapidly. A nonlinear relation between the effective moduli and the damage is proposed. The possibility and the advantage of using network model to study the constitutive relation are discussed.