Buckling/fracture behaviour of GFRP laminated plates with initial delamination

GFRP laminated plates have such characteristic that a delamination easily takes place. Therefore, it is important to investigate into the reduction of the compressive strength of GFRP plates caused by the delamination. In this paper, the buckling tests and FEM analyses (FEA) of the GFRP laminated plates with initial delamination under thrust are performed. The GFRP plates which consist of E-glass fibers (Chopped Strand Mat and Balanced Woven Roving) and unsaturated polyester resins are considered. The buckling test is performed for the clamped rectangular plate with the initial delamination at the center or the corner of the plate. The elastic buckling behaviour is simulated by FEA using shell elements, and the energy release rate along delamination tip is calculated to examine the growth of delamination. The applicability of FEA is investigated through a comparison with buckling test results. A series of FEA is performed considering various size and location of delamination, and the influences of initial delamination on the buckling/fracture behaviour of GFRP plates are discussed.