复合材料机械连接数值模型和强度研究

摘要

Mechanical strength of single-bolt composite joints was investigated using the cumulative damage theory combined with the finite element substructure technique .In the finite element model of the joint , substructures of laminated plate and bolt were conceived according to their characteristics of loading .The effect of material properties degradation on the strength prediction was analyzed when the damage of laminated plate occurred .The in-vestigation reveals that the selection of parameter values for material properties degradation after the occurrence of damages in composite plays an important role in the prediction of joint strength and stiffness ,especially the selection of parameter values for material properties degradation due to compressive damage .A composite single-bolt joint for a kind of metal was analyzed .The predicted results of joint strength and stiffness with suggested selection of parame-ter values for material properties degradation achieve good agreement with test results .The introduction of substruc-ture technique distinctly improves the computing efficiency .%基于累积损伤理论结合有限元子结构方法对复合材料单钉机械连接强度进行了研究。根据层合板特性和螺栓受力特点，利用子结构建模技术分别构造层合板和螺栓的子结构。分析了层合板出现损伤时，材料参数退化对强度预测的影响。结果表明，连接件挤压损伤的退化参数取值在很大程度上影响结构强度预测的结果。针对金属-复合材料单钉连接件，通过适当的参数退化方式得到与试验结果相吻合的强度和刚度预测，而通过子结构的应用也提高了连接强度计算效率。