Probabilistic strength analysis of fiber composite structures using lamination parameters

Start Page
3813
End Page
3824
Citation
European Conference on Computational Mechanics: Solids, Structures and Coupled Problems, ECCM and 7th European Conference on Computational Fluid Dynamics, ECFD: 3813-3824 (2018-06)
Contribution to Conference
6th European Conference on Computational Mechanics: Solids, Structures and Coupled Problems, ECCM 2018 and 7th European Conference on Computational Fluid Dynamics, ECFD 2018  
Scopus ID
2-s2.0-85081064583
An approach is presented that allows using lamination parameters for probabilistic analyses of the onset of material failure of composite structures. Lamination parameters allow for describing the scatter of ply orientations with 12 parameters, independently of the number of plies. The probabilistic analysis is split into two steps. First, the stochastic distribution of lamination parameters due to scattering ply orientations is determined analytically. Secondly, the stochastic distribution of the structural response (buckling load, material failure) is determined using lamination parameters as random input parameters. The drawback of utilizing lamination parameters is that the information of a discrete stacking gets lost as the lamination parameters vary. A discrete stacking however is required to evaluate strength criteria like, for instance, the Tsai-Wu criterion. In the current contribution, for each strength evaluation a discrete stacking, which corresponds to a varied set of lamination parameters, is determined by optimization. Then, for each stacking the Tsai-Wu criterion is evaluated. The proposed approach requires a couple of steps, which are not required when directly considering ply orientation as random parameter. Still, the approach offers efficiency gain, which is demonstrated by examples with analytical and numerical objective functions.
Subjects
Composite structures
Lamination parameters
Probabilistic analysis