A VAM-based equivalent model for random vibration of composite sandwich plate with arrowhead-on cores

Abstract

The composite sandwich plate with an arrowhead-on core (arrowhead-on CSP) is a new type of composite structure that has the advantages of a low weight, high specific strength, high specific stiffness, and negative Poisson’s ratio. In this study, the equivalent plate properties were obtained using the variational asymptotic method (VAM) to asymptotically analyze the energy functional stored in the unit cell. On this basis, a two-dimensional virtual equivalent model was constructed for random vibration analysis using the pseudo excitation method. To verify the accuracy and effectiveness of the equivalent model, the dynamic behaviors (free and random vibrations) of arrowhead-on CSPs under different conditions were analyzed. The power spectral density (PSD), the root mean square (RMS) values of the lateral displacement, velocity, and acceleration responses under a base acceleration excitation, and the modal effective mass fraction under vibrations were also investigated. Finally, the effects of the layup configuration of the composite facesheets and the geometric parameters of the arrowhead-on core on the dynamic characteristics of the equivalent plate were studied. The study revealed that the equivalent model was very efficient and accurate in free and random vibration analysis, which provided a reference for the dynamic characteristic optimization of arrowhead-on CSPs.