Abstract
The contribution of this study is development of ductile crack propagation analysis using Gurson model to apply nonlinear programming. Although Gurson model enables us to realize ductile crack propagation along with complex fracture process by introduction of effects of voids into an elastoplastic material, numerical instability occurs because of the inequality constraint function representing coalescence between voids. To solve this optimization problem with inequality constrain, we developed the primal dual interior point method originally proposed by Krabbenhoft et al. as a solution method for the elastoplastic material without determination whether elastic or plastic condition in an existing return-mapping algorithm. In particular, the Karush-Kuhn-Tucker condition is transformed so that it works well even when the hardening coefficient becomes zero. Throughout the numerical examples, we demonstrate the capability of the developed method by comparison with the return-mapping algorithm under monotonic and cyclic loading condition.
