Carrera unified formulation for bending and free vibration analysis of sandwich plate with FG-CNT faces considering the both soft and stiff cores

In this article, the bending and free vibration behavior of sandwich plates reinforced with functionally graded carbon nanotube (FG-CNT) were investigated based on the Carrera unified formulation(CUF). CUF is a technique which can handle a large category of plate models in a unified way. For FG-CNT, variable kinematic method was used to apply the properties of functionally graded CNTs, which reduce the degrees of freedom and increase the accuracy of the results. Accuracy and efficiency of the presented solution procedure are demonstrated by comparing the obtained results for the sandwich panel with the solution are available. It can be seen that the CUF is the robust method for modeling the sandwich plate with every configuration of CNTs. It must be mentioned, one of the capability of the CUF is that allows us to study the soft core considering the flexibility of the core which not reported in the literature. Therefore, results indicate that the CUF is a suitable model for analysis of the FG-CNT sandwich panels with both stiff and soft cores. A detailed numerical study is performed to examine the influence of soft and hard cores, different plate thickness ratios, different volume fractions of the CNTs, core to face sheet thickness, and also different types of nanotube configurations FG-X, FG-O, FG-V?, and FG-?V.