A model of composite laminated Reddy plate of the global-local theory based on new modified couple-stress theory

In this article, based on the global-local theory, a model for a composite laminated Reddy plate of new modified couple-stress theory is developed for the first time. This model satisfies free surface conditions and the geometric and stresses continuity conditions at interfaces. Differing from existing modified couple-stress theory, an anisotropic constitutive relation is suggested. There is only one micro material characteristic length constant in each layer of the composite laminated plate. Principle of virtual work is employed to derive the equilibrium equations and the corresponding boundary conditions. With the example of a cross-ply simple-supported Reddy plate subjected to the bending load q0 = sin (πx/L)sin (πy/L), the transverse shear stresses at interfaces are addressed. Additionally, the numerical results show that the present plate model can capture the scale effect, especially the scale effect of the transverse shear stresses at interfaces of the composite laminated plate.