Structural reliability analysis of a laminated plate using the Reissner-Mindlin model and the finite element method

Resumo

The use of anisotropic laminated plates as structural elements has become increasingly common due to their ability to emphasize desired mechanical characteristics and reduce undesired ones, based on the laminate stacking sequence.
Although the application of structural optimization methods to define the optimum laminate stacking angle is common in the literature, an analysis of the influence of this angle on the behavior of the plate and the approximate identification of its failure mode is relevant when seeking to increase laminate efficiency. In addition, taking into account the uncertainties that affect the structural response of these elements is still under development and open to discussion. Structural reliability is a suitable tool for dealing with these uncertainties.
This article aims to analyze the influence of the stacking angle on the probability of plate failure, taking into account the probability distributions of the variables involved. In order to make a comparative analysis, different Structural Reliability methods are adopted, such as FORM and the Monte Carlo method, and several failure criteria - Tsai-Hill, Tsai-Wu, Hoffman and Maximum Stress. The analysis is based on a case study of a laminated plate subjected to transversal static loading. The plate is considered to be made up of orthotropic laminae in oblique directions. The structure is modelled using the Finite Element Method, using the Reissner-Mindlin kinematic theory in the linear elastic regime. The aim is to verify and discuss the influence of the stacking angle on the level of structural safety of laminated plates.