Analytical modeling of flexural behavior of advanced composite sandwich beams under nonlinear hygro-thermo-mechanical loads

Sandwich beams made of advanced materials are used in many engineering areas. This paper presents a study on the nonlinear hygro-thermo-mechanical coupling loading (NL-HTMCL). Various symmetric and non-symmetric sandwich beams with FG material in the skins of functionally graded sandwich beams (FGSBs) have been considered. The physico-mechanical properties vary gradually and continuously according to a power-law distribution of the constituent materials' volume fractions. A new quasi-3D high shear deformation theory is used here to study the behavior of multi-type sandwich beams. The present model adopts a new field of displacement, which includes indeterminate integral variables. The governing equations for this investigation are obtained through the principle of virtual displacement and solved via the Navier-type method. Further, the nonlinear hygro-thermo-mechanical coupling loading (NL-HTMCL) is involved in these equations. A series of parametric studies discussing the flexural behavior of composite sandwich beams under different sets of hygro-thermo-mechanical loading is carried out. Finally, the numerical results show that the NL-HTMCL significantly affects the flexural characteristics of tested beams.