Buckling analysis of quasi-isotropic symmetrically laminated rectangular composite plates with an elliptical/circular cutout subjected to linearly varying in-plane loading using fem

In this paper the effects of circular and elliptical cutout on the buckling behavior of a sixteen ply quasi-isotropic graphite/epoxy symmetrically laminated rectangular composite plate [0°/+45°/45°/90°]2s, subjected to various linearly varying in-plane compressive loads, numerically. Further, this paper addresses the effects of size of elliptical cutout, orientation of elliptical cutout, plate aspect ratio (a/b), plate length/thickness ratio(a/t) , boundary conditions on the buckling bahaviour of symmetrically laminated rectangular composite plates subjected to various linearly varying in-plane compressive loading is carried out using Finite element method (FEM). The results show that the buckling loads of rectangular composite plates subjected to linearly varying in-plane loads are decreased by increasing of cutout positioned angle β and increasing of c/b and d/b ratios . The magnitudes of buckling loads are decreased by increasing the plate aspect ratio (a/b) and length/thickness (a/t) ratio. It is observed that the buckling loads for composite plates under CC type boundary conditions are higher than those under CS type boundary conditions, irrespective of cutout shape ,size ,orientation of cutout and type of linearly varying inplane compressive load. It is observed that the buckling loads for composite plates under L4 type loading are higher than those under L1, L2 and L3 type loading, irrespective of cutout shape ,size ,orientation of cutout and boundary conditions.