Prediction of interlaminar stresses of an unsymmetric cross-ply laminate using layerwise and higher-order equivalent single-layer theories

In the present study, the layerwise theory (LWT) and the first-order shear deformation theory (FSDT) are used to analyze analytically the interlaminar stresses near the free-edges of a general (symmetric and unsymmetric) cross-ply composite laminate subjected to bending. The FSDT is employed to determine the global deformation parameters appearing in the displacement fields. The LWT is then utilized to determine the local interlaminar stresses within the boundary layer regions of laminates. To assess the obtained results from the LWT in conjunction with FSDT, the interlaminar stresses are also computed using higher-order equivalent single-layer theory (HESL) available in the literature. Comparison of results for edge-effect problems of several cross-ply laminates indicates high stress gradients of interlaminar normal and shear stresses near the edge of laminates. Also, LWT can predict interlaminar stresses more accurate than HESL.

Cross-ply laminate, Layerwise theory, Higher-order equivalent single-layer theory.