Reliability assessment of fiber-reinforced composite laminates with correlated elastic mechanical parameters

This paper is aimed at developing a novel reliability assessment approach for fiber-reinforced composite laminates with correlated elastic mechanical parameters. Firstly, based on non-statistical grey mathematical theory, uncertainty information including nominal values, standard variances, and uncertainty matrix can be evaluated for elastic mechanical parameters of composites. Here, uncertain parameters are dealt with as correlated interval variables. Furthermore, the first-order Taylor interval expansion method is developed for interval estimation of structural responses. Here, the correlations between any two parameters are taken into account. Finally, by virtue of obtained intervals for composite laminates, the non-probabilistic reliability measurement is adopted for reliability evaluation. Besides, in order to account for the feasibility and validity of the proposed method, two numerical examples are given including an uncertain buckling problem and a first-ply failure analysis with temperature and moisture effects for composites. The results show that the proposed method can be applied efficiently in the process of reliability evaluation for composites. It can be concluded that it is appropriate to take correlations of uncertain elastic parameters into account for reliability assessment of composites, which can give birth to a more reasonable and better result.