An embedded crack model for finite element analysis of concrete fracture

This paper presents a numerical implementation of cohesive crack model for the analysis of concrete fracture based on the strong discontinuity approach. A simple central force model is used for the stress vs. crack opening law. The only material data required are the elastic constants and the mode I softening curve. The additional degrees of freedom defining the crack opening are determined at the crack level, thus avoiding the need of performing a static condensation at the element level. The need for a tracking algorithm is avoided by using a consistent procedure for the selection of the separated nodes, and by letting the crack embedded in the finite element to adapt itself to the stress field while the crack opening does not exceed a small threshold value. Numerical simulations of well known experiments are presented to show the ability of the proposed model to simulate fracture of concrete.