Analytical model of the bond stress-slip relationship for reinforced concrete due to splitting failure

Abstract

This paper develops a new bond stress-slip relationship for reinforced concrete, which considers the evolution of the concrete confinement capacity due to splitting failure of concrete cover. Considering fracture characteristics of the concrete, the improved thick-walled cylinder model is used to analyze the radial stress and radial deformation at the interface between rebar and concrete for different damage stages. A new assumption of circumferential deformation is proposed to estimate the deformation field of the inner cracked concrete, and the linear crack profile is assumed to calculate the distribution of cohesion on the crack surface. The radial strain is calculated with elastic constitutive relation including the Poisson’s effect. The descending branch of the confinement model can be derived with the linear response between the radial stress and radial deformation. The presented concrete confinement model can be transformed into bond stress-slip relationship based on the stress and deformation analysis at the interface. Comparing with experimental results, it is indicated that the results calculated with bond stress-slip relationship proposed in this paper is more reasonable.