A PROBABILISTIC APPROACH TO FAILURE PREDICTION OF FRP LAMINATED COMPOSITES

Abstract

The failure of fiber-reinforced plastic (FRP) laminated composites is examined, taking into account statistical aspects of the basic strength properties of the material The purpose of the analysis is to establish simple rules and methodologies for failure prediction under specific reliability requirements. An analytical approach is developed for the prediction of failure under general in-plane loading, consisting of a functional expansion technique for the derivation of the cumulative distribution Junction of the failure condition. A semideterministic method is also examined, according to which the failure criterion is used in the usual deterministic way but with the basic strength values at a certain reliability level. The two methods are gradually built up by first examining their effectiveness on the failure prediction of unidirectional laminae. Results for the case of a unidirectional laminate are presented for the case of off-axis layers, and both methods are shown to yield results in fair agreement with Monte Carlo simulated ones and experimental data. For the more general case of multilayered composites, comparison of theoretical results with numerical simulated data and experimental ones reveals that both methods hold their effectiveness.