Hybrid Model for Discrete Cracks in Concrete

Abstract

A method is proposed for the analysis of mode I and mixed mode crack propagation in concrete. It is based on a hybrid technique which uses finite elements to represent the uncracked specimen, and distributed dislocations to represent the crack. Consequently, no remeshing of the finite elements is required after crack propagation. This method is improved and further developed to make it applicable to concrete by incorporating the nonlinear traction transfer characteristics in a crack in concrete. By incorporating expressions obtained from previous studies to represent the aggregate interlock and imperfect debonding (i.e., tensile softening) in the crack, the major sources of nonlinearity caused by cracking are accounted for. Crack propagation in a single edge notched beam, subjected to four point bending, is modeled correctly, while the predicted reduction in load corresponds satisfactorily with the experimentally obtained results.