Analytical model for evaluating bond strength of steel rebar in cracked concrete considering confinement effect.

• A novel failure criterion, accounting for various degrees of concrete cracking and confinement levels, is presented to estimate the bond strength between steel rebar and concrete. • An interlock capacity coefficient, considering the surface properties of both concrete and steel rebars, is presented to adjusts concrete compressive strength. • Opening of concrete crack at the peak bond stress, alongside sliding, proves crucial to the failure criterion. • A practical computation approach is presented to estimate the bond strength of cracked RC members with commonly used confinement configurations. This study delves into the intricate relationship between concrete cracking and bond strength, a critical factor in transferring forces between concrete and steel rebars. While previous research has often overlooked the impact of concrete cracking on bond strength and overestimated the beneficial effects of external confinement, this study aims to fill these gaps. A new failure criterion is introduced to predict bond strength of steel rebar in cracked concrete, considering the influence of concrete crack roughness and steel rebar surface features on force transfer at their interface. This criterion incorporates an interlock capacity coefficient that considers crack kinematics and the mentioned factors, enhancing the evaluation of effective compressive strength of cracked concrete in the limit analysis. Leveraging the Mohr-Coulomb failure criterion, an adaptable failure criterion accounts for crack kinematics, concrete damage, and confinement level to assess force transfer at the concrete/steel rebar interface. The developed criterion offers a practical calculation method to estimate bond strength in cracked reinforced concrete (RC) members with various confinement setups. Validation of this criterion and approach involved comparison against experimental results from 127 specimens, confirming its effectiveness and reliability in predicting bond strength in real-world scenarios. [ABSTRACT FROM AUTHOR]