Fracture in shells

Shell structures are frequently encountered in various fields of engineering, e.g., aerospace, automotive and civil. An accurate prediction of their fracture is a crucial aspect for the safety assessment of engineering structures, and at the same time a challenging task. With the aim to provide a general, flexible and robust methodology to deal with fracture in thin and thick shells, we combined phase-field modeling of fracture with different types of shell kinematics. We started with a phase-field fracture model for solid shells, and then proposed a formulation for Kirchhoff-Love shells, which we recently extended to Reissner-Mindlin shells in collaboration with our colleagues at external page RWTH Aachen. In the latter two cases, the delicate issue was to deal appropriately with the asymmetry of the fracture behavior in tension and compression, while defining the phase-field variable only on the mid-surface of the shell. In all three cases, we exploited the advantages of isogeometric basis functions for the discretization. With several numerical examples we showed that the proposed approaches can naturally handle crack initiation, propagation, branching and merging.