A finite element model for propagating delamination in laminated composite plates based on the Virtual Crack Closure method

In the paper, a simple and efficient algorithm to track a moving delamination front of arbitrary shape, using a laminated finite plate element model in conjunction with the Virtual Crack Closure Technique (VCCT), is proposed. The solution requires the calculation of the virtually closed area in front of the delamination, which is approximated by means of a 6-node-polygon, the delamination opening behind this front and the reaction forces in the nodes at the delamination front. These quantities are calculated in a local coordinate system (LCS) defined in the nodes along the delamination front. Using the proposed algorithm, arbitrary meshes composed of 4- and 9-node quadrilateral finite elements can be considered. The proposed model is developed in the context of a layered finite element plate model. To prevent interlaminar penetration of adjacent layers in the delaminated region, an algorithm recently proposed by Marjanović et al. (2015) is adopted. The model performance is demonstrated by re-analyses of the Double-Cantilever-Beam problem, for which analytical solutions exist, and by transient analyses of laminated composite plates with propagating delamination fronts.