ABSTRACT
A formulation for the analysis of fracture in concrete structures has been recently developed and is used here to study interaction of cracking in plain concrete. The concrete is represented by an assembly of triangular elements. The material within the triangular elements, which are assigned average homogeneous properties, remains elastic. Fracture is captured through a constitutive softening-fracture law at the boundary nodes between triangular elements. This paper concentrates on the analysis of various fracture modes in a plain concrete beam under four point bending with several notches and examines the interacting crack itineraries. At various stages in the loading history multiple equilibrium paths exist which correspond to different crack paths. At these bifurcations in the equilibrium path the path with the minimum second order work is chosen as the critical path. The method presented has the advantage that there is no remeshing required and the technique identifies the various equilibrium solutions available.
