DYNAMIC STABILITY OF COMPOSITE LAMINATES

A general framework has been developed to investigatedynamic stability of composite plates under dynamicand static compressive loads. A variationallyconsistent, higher-order shear deformation theory hasbeen used to model the displacement field. The linear strain-displacement relationshipcorresponding to the small deformation assumption isused first. Both transverse shear and rotary inertiaeffects are taken into account. The mathematicalmodel is implemented using the finite element approach.The impact of delamination on the naturalfrequencies, critical buckling load, and instabilityregions is investigated Parametric studies areconducted to investigate the influence ofdelamination placement and size, boundary conditions,plate thickness, static pre-stress, and stackingsequence on the instability regions.Finally, the importance of geometric nonlinearity isstudied by introducing von Kármán nonlinearity.Natural frequency results are obtained for squareisotropic and cross-ply laminates and compared withavailable analytical data. The effect of geometricnonlinearity on the principal instability region isalso investigated for cross-ply laminates.... Mehr