Stochastic finite element on vibration analysis of composite plates having random damping parameters

Damping parameters of composite structures possess significant uncertainty due to the structural complexity of such materials. Considering the parameters as random variables, this work uses the generalized polynomial chaos (gPC) expansion to capture the uncertainty in the damping and in the vibration responses of structures. A non-sampling based stochastic finite element formulation for damped vibration analysis is developed in which the gPC expansion is used to represent damping uncertainty and stochastic responses with unknown deterministic functions. The constructed gPC expansions for the parameters are used as random inputs to the FEM model to realize the responses on a few number of collocation points generated in random space. The realizations then are employed to estimate the unknown deterministic functions of the gPC expansion approximating the responses. The application of the proposed method is practiced on sample fiber-reinforced composite plates having random modal damping parameters. Utilizing a few random collocation points, the method indicates a very good agreement compared to the sampling-based Monte Carlo simulations with large number of realizations.