Crack-based analysis of concrete with brittle reinforcement

Brittle reinforcement (such as fibre-reinforced plastic) is being developed as an alternative to traditional steel reinforcement. The lack of ductility in a brittle-reinforced beam means that there is very little potential for stress redistribution, and the lower-bound theorem of plasticity (which allows many of the assumptions made in steel-reinforced concrete analysis) cannot be applied. Analysis of brittle-reinforced concrete must be based on a detailed examination of compatibility requirements within a beam, of which the cracks form an important part. A crack-based model is developed in this article, based on compatibility requirements where reinforcement crosses a crack, and compatibility in the compression-zone concrete. The analysis incorporates dowel-rupture of the reinforcement, and the reduced strength of a corner of a stirrup. It highlights the need for further research into flexure-shear of the compression zone, dowel-splitting, and local failure of the concrete. The crack-based model is used ...