Buckling analysis of delaminated laminates with consideration of contact in buckling mode

This paper concerns the buckling load analysis of laminates with a pre-existing delamination, using the Þnite element method based on the Mindlin plate theory. To deal with the contact problem in the buckling mode, an e¤ective algorithm is presented. In this method, an iterative updating process based on the Þrst-order sensitivity analysis and the quadratic programming technique is proposed to compute the Þctitious forces in contacting areas at Þrst. These Þctitious forces are then transferred into the sti¤ness parameters of some artiÞcial springs. The original sti¤ness matrix of system can be modiÞed, using these artiÞcial springs. Finally, the penetration between two delaminated layers in the buckling mode can be prevented e¤ectively. Numerical examples show that this method is very e¦cient to solve the contact problem in eigenvalue analysis from the viewpoint of its accuracy, stability and convergence speed. The e¤ects of contact and delamination size on the buckling load analysis are also investigated. Copyright