Strategies to Improve Convergence After Degeneration of the Initial Finite Element Mesh
In some cases, the finite element solution does not converge because of severe distortions in the finite elements of the initially generated mesh. Numerical strategies aimed to overcome such issues are discussed in this contribution. The context is the numerical simulation of concrete/RC beams strengthened with composite material. The structural element is considered as a multiple-component system: constitutive relations and local failure criteria are defined for all components, i.e., for all materials: concrete, steel and composite material. A damage-based constitutive law is retained for concrete. As a result of this procedure application, zones of reduced or of zero or rigidity are formed in the medium which is initially defined as homogeneous and isotropic. A new initial state for the subsequent post-failure solution is defined on the basis of the state at the time preceding the loss of convergence. After homogenization, zones containing distorted finite elements are ‘healed’.
KeywordsFEM Large displacement response Post failure behavior
- 3.Mazars, J.: Application de la Mécanique de l’Endommagement au Comportement Non-linéaire et à la Rupture du Béton de Structure. PhD thesis, Paris 6 University, Paris, France (1984)Google Scholar