A Simplified Approach to Joint Shear Behavior Prediction of RC Beam-Column Connections

An extensive experimental database of reinforced concrete (RC) beam-column connections subjected to cyclic lateral loading has been constructed. All cases within the database experienced joint shear failure, either in conjunction with or without yielding of longitudinal beam reinforcement, representing damage within a joint panel that was the main contributor to total lateral deformation. (Cases having damage within a joint panel caused by other premature failure modes (e.g., anchorage failure) are not included in the database.) Using the experimental database, envelope curves of joint shear stress vs. strain behavior were developed by connecting key points such as cracking, yielding, and peak loading. Joint shear stress and strain models at peak response have been developed by a Bayesian parameter estimation method based on the experimental database. At other key points, important influence parameters are also identified by constructing joint shear stress and strain models in conjunction with the Bayesian parameter estimation method. Then, a complete RC joint shear stress vs. strain model (including post-peak behavior) is suggested using simplified joint shear stress and strain models at peak response; effects of key parameters on the suggested behavior models are evaluated. Finally, the ASCE/SEI 41 joint shear behavior model has been examined using the constructed database—specific joint shear strength factors and plastic joint shear deformation values are recommended for use when following that approach.