Unified Model of Local Bond between Deformed Steel Rebar and Concrete: Indentation Analogy Theory and Validation

Abstract

Two distinct groups of bond models were developed on the basis of dominant concrete splitting and rebar–concrete interfacial failures, respectively. Their accuracy highly depended on the specific test data sets selected in analysis and validation. In this study, a unified model of local bond is proposed and developed on the basis of the indentation analogy at the rib front of the deformed rebar and on the concrete plastic deformation around the rebar. Unlike existing models, the unified model is completely validated with all sets of test data available in the literature. It can accurately predict the transition mechanism of failure modes from concrete splitting to rebar pullout. The predicted bond strength is in excellent agreement with experimental results as the rib spacing-to-height ratio changes in practical range.