Thanh Hai Tuan Tran's thesis defense

Modeling damage and fracture of thin structures via a phase profile.

This thesis focuses on the numerical modeling of damage and failure of thin structures using the phase field (PF) method.

Literature analysis has shown that the CP method is powerful and can automatically handle both crack initiation and propagation without the need to mesh the crack front. Moreover, as a member of the family of non-local methods, the CP technique does not suffer from localization problems. The CP method has been widely used for modeling solid continuous media, however little or no work has been done on its extension to thin structures such as plates and shells.

In this work, the CP method has been formulated and extended to damage and fracture modeling of thin shell-like structures. An incremental scheme has been developed to solve the nonlinear problem in implicit statics, using an alternating iterative algorithm. The damage irreversibility condition was forced by the penalty technique. A 4-node shell element with shear effects has been developed and the damage is approximated by nodal approximation to ensure continuity throughout the structure.

The procedure developed has been successfully applied to solve some academic fracture mechanics applications, demonstrating its potential.

Phase field, damage, fracture, thin structures, alternating algorithm.