首先,为研究复合材料层合板在准静态载荷下的基体裂纹演化特征,提出了一个基于能量的协同损伤演化模型.然后,通过模型对损伤进行了多尺度分析:从微观角度,采用三维有限元方法求得裂纹表面位移;从宏观角度,结合裂纹表面位移,推导了萌生基体裂纹的能量释放率.最后,根据裂纹萌生准则对基体裂纹的演化过程进行预测.模型考虑了演化过程中损伤的相互影响、残余应力、基体材料非线性、材料初始损伤分布及损伤演化的不均匀性.根据演化分析流程计算了[±θ/904]s铺层玻璃纤维复合材料的基体裂纹演化过程.结果表明:这一模型能够准确地预测准静态载荷下复合材料层合板基体裂纹的损伤演化规律.
First, in order to investigate the evolution characteristics of matrix cracks in composite laminates under quasi-static loading, a synergistic damage evolving model based on energy was proposed. Then, the damage was analyzed in multi-scale through the model: in micro-level, crack surface displacements were calculated by three-dimensional finite element method, in macro-level, the energy released rates of matrix crack initiation were obtained with the crack surface displacements. Finally, the evolving process of matrix cracks was predicted by the crack initiation criterion. The model had taken the damage interaction, residual stress, nonlinearity of matrix, material initial dam- age distribution and inhomogeneity of damage evolving in evolutionary process into consideration. According to the evolutionary analysis process, matrix crack evolution process in glass fiber composites with the configuration of [-θ/904]s was analyzed. The results show that the model is capable to predict the damage evolution laws of matrix cracks of composite laminates under quasi-static loading.