Propagation and band width of smeared cracks

Abstract

The crack band approach (in the smeared crack concept) is widely used for the modeling of concrete fracture and is an important analysis technique within advanced engineering. However, the simulations can be impeded by mesh-induced directional bias. Cracks prefer to propagate along continuous mesh lines, which causes a dependency of the numerical results on the structure and orientation of the finite element discretization. In this PhD research, two different enhancements of the crack band approach are proposed to reduce the mesh bias as much as possible. The performance of both enhancements is investigated by simulations of plain concrete fracture tests and a shear critical reinforced concrete beam without shear reinforcement. Both enhancements increase the accuracy of the crack band approach in the smeared crack concept and simultaneously preserve its relative simplicity. Hence, they can be valuable for engineering practice, supporting reliable predictions of ultimate load capacities, failure mechanisms and post-peak behaviors of quasi-brittle reinforced concrete structures.