Multidomain modeling and analysis of delaminated stiffened composite shells

A unified method is presented for modeling delaminated stiffened laminated composite shells, synthesizing accurate multiple postbuckling solution paths under compressive loading, and predicting delamination growth. A multidomain modeling technique is presented for modeling the delaminated stiffened shell structures. Error-free formulations are presented for a two-noded curved stiffener element and a three-noded shell element for geometrically nonlinear applications. An accurate and simple automated solution strategy based on Newton-type iterations is presented for predicting the general geometrically nonlinear and postbuckling behavior of structures. Finally, a simple method is derived for predicting the delamination growth by using the pointwise energy release rate at the delamination front as evaluated from the three-dimensional J integral.