적층복합재 구조물에 대한 확률유한요소법의 적용

Abstract

The stochastic finite element method based on second-order perturbation technique is developed for the probabilistic analysis of laminated composite structures in which physical properties have uncertainties and variability. The elastic modulus in fiber direction, fiber angle of each layer, thickness of laminate, and curvature are modeled as random parameters. Developments are applied to the first order shear deformation shell element. Numerical results are presented for a cantilever plate. The validity and accuracy of the method is verified through comparing the results with those obtained by the Monte Carlo simulation. Statistics of strains and stresses are derived very accurately by considering the randomness of the strain-displacement relation and induding the effect of fluctuation of principal material coordinates. It is shown that probability distribution of response of the composite structure can be assumed to be normal distribution, and probabilistic distribution of the structural response of composite structure can be evaluated quantitatively.