Advantages of employing a full characterization method over FORM in the reliability analysis of laminated composite plates

Predictions of the failure of composite structures under uncertainties have become an important topic of research. In engineering practice, one is usually interested in evaluating the probability of failure of the system under analysis. Hence, reliability methods such as the First Order Reliability Method (FORM) have been widely employed. However, some problems may arise in the application of these reliability methods, such as, lack of precision and convergence issues. From full characterization methods, such as the polynomial chaos representation, any probabilistic or statistical information may be derived, even the ones provided by reliability methods. Sometimes, the solution of this problem is claimed to be very complex, leading to high computational cost. However, as presented by the authors in a previous work, the full characterization may be simple to implement, providing much more information about the random variable under analysis. Thus, the main goal of this paper is to show that this full characterization approach may be applied to the reliability assessment of laminated composite plates overcoming some of the drawbacks of the FORM. Several examples are presented in order to highlight the advantages of the proposed approach.