Validation of a plasticity bond model for steel reinforcement

Abstract

The validation of a plasticity model for bond between ribbed, steel bars and concrete is discussed. The model relates local slip and radial dilation to bond stress and radial confinement stress, i.e. it provides an interface characterization of the behaviour of a finite-thickness region around the bar—the bond zone. The validation study considers experimental results from six independent investigations. The specimens are all pull-out specimens but differ significantly in size and configuration. Models for each specimen, based on a single bond model calibration, reproduce the experimental results with acceptable accuracy. The response over the full range of slip and the mode of failure are examined. Some of the model's strengths, weaknesses, and potential improvements are discussed. For the most part, the models predicts the experimental bond strength within 20 per cent and exhibits the potential to predict both pull-out and splitting failures. Copyright © 1999 John Wiley & Sons, Ltd.