Partial-interaction tension-stiffening properties for numerical simulations

Abstract

The partial-interaction behaviour of tension-stiffening affects or controls virtually all aspects of reinforced concrete member behaviour as it controls the formation and widening of cracks as well as the load developed within the reinforcement crossing a crack. In this article, simple closed-form solutions for the tension-stiffening behaviour of reinforced concrete prisms are derived through mechanics and are presented in a form that can be easily used in both displacement-based and strain-based numerical modelling. This research quantifies not only the pseudo material properties of tension-stiffening such as equivalent stress–strain relationships or equivalent moduli that simulate the increase in reinforcement stiffness associated with tension-stiffening but also the crack spacings and crack widths. It is shown that the bond properties have little, if any, effect on tension-stiffening but a major effect on crack spacings and widths.