A new triangular element to model inter-laminar shear stress continuous plate theory

An efficient triangular element based on an inter-laminar shear stress continuous plate theory is developed and applied to the analysis of composite and sandwich plates under different situations to study the performance of the element. The plate theory represents parabolic through thickness variation of transverse shear stresses where the continuity condition of these stresses are satisfied at the layer interfaces. It also satisfies transverse shear stress free condition at the top and bottom surfaces of the plate. The most attractive feature of the plate theory is that the basic unknowns are same as those used in first-order shear deformation theory. The only problem lies with this elegant plate theory is found in its finite element implementation, as it requires C1 continuity of transverse displacement at the element interfaces. This is a well-known problem of thin plate elements, which is also found in some other refined plate theories. Although there are some elements based on these refined plate theories but the number of such elements is very few and they possess certain drawbacks in general. Keeping these aspects in view, an attempt has been made in this study to develop a six-noded triangular element having equal degrees of freedom at each node