Reliability assessment of laminated composite plates with random strength parameters

A method is presented for the reliability assessment of transversely loaded laminated composite plates with random strength parameters. The proposed m ethod is constructed on the basis of the first-ply failure method and the s eries system hypothesis. The first-ply failure analysis of a laminated plat e is achieved via the use of a phenomenological failure criterion and the f inite element method. In the reliability analysis, the independent (maximum stress) as well as the dependent (Tsai-Hill) failure criteria are used to establish the limit state equation; a direct numerical integration method t ogether with the series system hypothesis are adopted to compute the reliab ility of the plate. Experimental investigations of lamina strength distribu tions and first-ply failure of laminated composite plates were performed. I t has been found that lamina strengths and first-ply failure load can be we ll fitted by Weibull distributions. The baseline probability distributions of lamina strength parameters determined from the tests are then used in th e reliability analysis of the laminated composite plates. The accuracy of t he proposed method in reliability prediction of the laminated composite pla tes of different sizes is verified against the experimental results.