Cracking and deformation of axially reinforced members subjected to pure tension

This paper describes work carried out as part of a major experimental and theoretical investigation into tension stiffening. This work was carried out at the universities of Leeds and Durham. The experimental work enabled a detailed study to be undertaken of the behaviour of concrete in tension surrounding reinforcing bars. This study showed that a more-or-less linear variation in concrete and steel stress occurred in the region affected by a crack and also that behaviour of the concrete in the region of a crack remained substantially elastic. The experimental study permitted equations to be developed to predict the deformations and crack widths in axially reinforced tension members. Tests of the formulae for crack widths are reported and the formulae are shown to be satisfactory. A more detailed model of the behaviour in the region of a crack is proposed and shown to be reasonable.