A layerwise/solid-element method of the linear static and free vibration analysis for the composite sandwich plates

In the traditional analysis schemes of the composite sandwich structures the core is firstly simplified as an equivalent anisotropic material and then modeled by the plates and shells theories. Its main disadvantage is that the equivalent core will result in large equivalent error especially in the key area and the thick core will further reduce the analysis accuracy of the plates and shells theories. Therefore, a layerwise/solid-element method (LW/SE) is proposed in this paper, in which the layerwise theory is used to model the behavior of the composite laminated facesheets while the eight-noded solid element is employed to discretize the core. Three models, the full model, the local model and the equivalent model, are presented to model the core. Several numerical examples are investigated and the static analysis and free vibration analysis of the composite sandwich plates are tested. The results of proposed method are in good agreement with those of 3D finite element model. A detailed comparative study is conducted to investigate the performance of three modeling schemes for static analysis and free vibration analysis problems.