Reduced-order modeling analysis of shell structures buckling using a co-rotational solid-shell element

The solid-shell elements can simplify the modeling process of the three-dimensional thin-walled structures that are commonly used in aerospace engineering. In this work, an efficient locking-free 8-node solid-shell element, termed SolSh8, is developed for geometrically nonlinear buckling analysis of shell structures. The solid-shell element is developed based on the conventional brick solid element with only translational degrees of freedom. The Assumed Natural Strain (ANS) method and the Enhanced Assumed strain (EAS) method are used to improve the linear performance of the element formulation. The proposed element is implemented into the co-rotational formulation of the Koiter-Newton method. The geometrically nonlinear equilibrium path of the structure can be traced efficiently benefiting from the reduced order model used in the Koiter-Newton method. Numerical examples demonstrate the excellent performance of the proposed method.