A Variability Study on the Response of Composite Structures based on Sensitivity Indices

The problem of uncertainty propagation in composite laminate structures is studied. An approach based on the optimal design of composite structures to achieve a target reliability level is proposed. Using the uniform design method (UDM), a set of design points is generated over a domain centred at mean values of random variables, aimed at studying the space variability. The most critical Tsai number, the structural reliability index and the sensitivities are obtained for each UDM design point, using the maximum load. Using the UDM design points as input/output patterns, an artificial neural network (ANN) is developed based on supervised evolutionary learning. Finally, using the developed ANN-based Monte Carlo simulation procedure, the variability of the structural response based on global sensitivity indices is evaluated. The most important sources of uncertainty are identified.