Probabilistic dynamic buckling of composite shell structures

A computationally effective method is described to evaluate the probabilistic dynamic buckling of thin composite shells. The method is a judicious combination of available computer codes for finite element, composite mechanics and probabilistic structural analysis. The solution method is an incrementally updated Lagrangian. It is illustrated by applying it to a thin composite cylindrical shell subjected to dynamic loads. Both deterministic and probabilistic buckling loads are evaluated to demonstrate the effectiveness of the method. A universal plot is obtained for the specific shell that can be used to approximate buckling loads for different loading rates and different probability levels. Results from this plot show that the faster the rate, the higher the buckling load and the shorter the time. The lower the probability, the lower the buckling load for a specific time. Probabilistic sensitivity results show that the ply thickness, the fiber volume ratio, the fiber longitudinal modulus, dynamic load and loading rate are the dominant uncertainties in that order.