Delamination growth of laminated circular plates under in-plane loads and movable boundary conditions

• Evaluation of the total energy and its individual components for delamination in circular composite laminated plates.
• Modeling plates with four regions and utilizing the variational principle and Griffith criterion.
• Model of geometrical nonlinearity for the composite plates subjected to axisymmetrical delamination.
• Effects of delamination radius, depths and material properties on the delamination growth.

An investigation is made on interlaminar delamination growth of composite laminated circular plates under in-plane loads and movable delamination boundary conditions. A four-dissociated-region model is developed on the basis of von-Karman plate theory. The model is geometrically nonlinear and the laminated circular plate considered is subjected to axisymmetrical delamination. The effects of transverse shear deformation and contact effect of the delamination on the laminated plates are taking into account in the development of the governing equations of the laminated circular pates with random axisymmetrical delamination. The formulas for describing the total energy release rate and its individual mode components along the delamination front are also derived with considerations of Griffith criterion for fracture. Based on the model established, the delamination growth is numerically studied; and the influences of the parameters such as delamination radii and depths, together with material properties of the plates on the energy release rate are analyzed in detail.