Nonlinear dynamic response of sandwich plates with FGM face sheets resting on elastic foundations in thermal environments

This paper presents an investigation on the nonlinear dynamic response of sandwich plates with FGM face sheets resting on elastic foundations in thermal environments. The material properties of FGM layer are assumed to be graded in the thickness direction According to the Mod-Tanaka scheme. The governing equations of the plate that includes plate-foundation interaction are solved by a two-step perturbation technique. The thermal effects are also included and the material properties of both FGM face sheets and homogeneous core layer are assumed to be temperature-dependent. Two cases of the in-plane boundary conditions are considered. Initial stresses caused by thermal loads or in-plane edge loads are introduced. The numerical illustrations concern the nonlinear dynamic response of sandwich plates resting on Pasternak elastic foundations under different sets of thermal environmental conditions, from which results for single-layer FGM plates are also obtained for comparison purposes. The numerical results show that foundation stiffness and initial stress have a significant effect on the dynamic response of both single-layer and sandwich FGM plates. They also show that the core-to-face sheet thickness ratio has a significant effect on the dynamic response of sandwich FGM plates. The results reveal that the volume fraction distribution of FGM layer has a significant effect on the dynamic response of single-layer FGM plates, whereas this effect is less pronounced for the sandwich plate with FGM face sheets. (C) 2012 Elsevier Ltd. All rights reserved.