Numerical Investigations of Stresses and Damage Distributions on the Layers of a Sandwich Beam with Composite Laminated Faces Subjected to Bending (original) (raw)
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IJERT-Flexural and Dynamic Characteristics of FRP Composite Sandwich Beam
International Journal of Engineering Research and Technology (IJERT), 2020
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The initiation of failure in composite sandwich beams is heavily dependent on properties of the core material. Several core materials, including PVC foams and balsa wood were characterized. The various failure modes occurring in composite sandwich beams are described and their relationship to the relevant core properties is explained and discussed. Under flexural loading of sandwich beams, plastic yielding or cracking of the core occurs when the critical yield stress or strength (usually shear) of the core is reached. Indentation under localized loading depends principally on the square root of the core yield stress. The critical stress for facesheet wrinkling is related to the core Young's and shear moduli in the thickness direction. Experimental mechanics methods were used to illustrate the failure modes and verify analytical predictions.
Journal of Serbian Society for Computational Mechanics, 2015
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Ecf17 Brno 2008, 2013
An investigation was conducted on failure of composite sandwich beams under threepoint bending and in cantilever beams under end loading. The beams consisted of unidirectional carbon/epoxy facings and a variety of core materials, including aluminum honeycomb, PVC closedcell foams, polyurethane foam and balsa wood. The constituent materials were fully characterized and in the case of the core materials, failure envelopes were developed for biaxial states of stress. Deformation and failure mechanisms include core shear failure and compression facing wrinkling. Results were obtained for stress (strain) distributions in the linear and nonlinear/plastic range of the core, critical failure loads due to shear core failure and compression facing wrinkling and their dependence on geometrical dimensions, material parameters and loading conditions. w