Study of bending behavior of delamination in circular composite plate using third order shear deformation theory

The composite structures have many applications in military, aerospace, marine, transportation, and sporting goods industries where the strength to weight performance of the structure is especially important. The quality and strength of composite plates are always decreased due to defects arisen during construction and service. One of the important and most common defects in composite plates is delamination and its propagation. In the present research the delamination propagation of a composite circular plate is investigated. The geometry of delamination is also assumed to be circular and the plate is subjected to a bending load. The nonlinear governing equations are first obtained using third order shear deformation theory. Then, these equations are coded and solved using spectral homotopy analysis method (SHAM). Moreover, the effects of radius and depth of the delamination on energy release rate are studied. It can be seen that the radius of delamination increases, the strain energy release rate increases to a critical radius 0.7 and then decreases. Also, with increasing delamination depth from 0.14 to 0.48, the the strain energy release rate increases. The results of the present research are in good agreement with the FE results and also the available analytical results.