复合材料刚度性能表征的协同损伤力学模型

针对复合材料层合板的弥散型损伤，提出一个刚度性能表征的协同损伤力学模型. 该模型兼顾了微观物理损伤响应和宏观材料刚度性能表征. 从微观角度，建立细观RVE 模型求解裂纹表面张开位移和滑开位移，以此定义损伤张量，并在宏观上通过对材料应变和损伤表面位移进行均匀化处理，建立单向板或层合板的损伤刚度矩阵和损伤张量之间的联系. 以基体裂纹为例，详细分析并建立了横向裂纹和纵向裂纹的损伤本构. 计算了±θ/90₄]_S 铺层层合板中基体横向裂纹对刚度性能的影响，结果表明该方法能够准确地预测复合材料层合板由损伤导致的刚度性能衰减. 

SYNERGISTIC DAMAGE MECHANIC MODEL FOR STIFFNESS PROPERTIES OF COMPOSITE LAMINATES

In connection with diffused damage in composite laminates, a synergistic damage mechanic model was proposed for the stiffness properties. The model included the microcosmic responses of the physical damage and macroscopic performance of the material's stiffness. In micro-level, mesoscopic RVE (representative volume element) model was established to obtain crack opening displacement and crack sliding displacement, which were used to define the damage tensor. In macro-level, through homogenizing the material strain and the surface displacement of the damage, the relationship of the stiffness matrix of unidirectional laminate or laminates in damage statue and damage tense was set up. As matrix crack for example, the constitutive relations of the laminates with transverse and longitudinal cracks were constructed, respectively. The influences of the transverse matrix cracks on the stiffness properties of the laminates ±θ/90₄]_S were analyzed with the present model and showed that it is capable to predict the reduction of the stiffness properties resulted from the damage in the laminates.