Bucking and vibrations of unsymmetrical laminates resting on elastic foundations under in-plane and shear forces

摘要

Buckling loads, free vibrations and vibrations with initial in-plane stresses for moderately thick, simply supported rectangular laminates resting on elastic foundations such as the Pastern type, are examined in this paper. The analysis is carried out considering unsymmetrical flat laminates subjected to biaxial compression and shear loads. First-order shear deformation theory, in conjunction with the Rayleigh-Ritz method is used for the evaluation of buckling loads and vibrations by means of a standard eigenvalue procedure. A large numerical investigation is intended to demonstrate the influence of laminate parameters (fiber orientations, degree of anisotropy, number of layers) and foundation parameters (modulus of surged reaction and shear modulus); the results obtained are reported and discussed in the paper.