Failure and reliability analysis of pinned-joints composite laminates: Effects of stacking sequences

The present work deals with the failure and reliability analysis of composite pinned-joints using theoretical models based on Weibull distribution function with experimental results for a guideline of safe design strength, which are not studied yet. The purpose of this work is to study the failure and reliability analysis of pinned-joints in glass-fiber reinforced epoxy composites. The influence of specimen stacking sequences on the mean bearing strength, mean ultimate failure stress, failure displacement and bearing stiffness was investigated. Four configurations were studied: [0/90](2s), [15/-75](2s), [30/-60](2s), and [45/45](2s). The results showed that the apparent bearing stiffness was qualitatively agreed with the predicted Young's modulus. Specimens with [0/90](2s) stacking sequence have the maximum failure displacement and ultimate failure stress compared with the other stacking sequences. On the other hand, specimens with [45/-45](2s), stacking sequence have the maximum failure displacement and bearing capacity based on the first-peak criterion. Theoretical models have been developed to predict the characteristic bearing strength, lower bound bearing strength, and safe design bearing strength at different reliability levels. These models show that the penalty paid to gain high reliability bearing strength, R = 0.99, in some cases, was more than 50% of the mean value. (c) 2012 Elsevier Ltd. All rights reserved.