New Model for Estimation of Shear Strength of Reinforced Concrete Interior Beam-Column Joints

A new model is developed for estimating the shear strength of RC interior beam-column connections. The new model is based on the methods used in current ACI and AIJ design codes with modifications for effective area of joint panel and effective concrete strength. A database of interior beam-column connections is constructed from previous experimental studies and the influence of transverse reinforcements in joint panel and axial force in columns are investigated. Since the investigation showed positive correlations between joint shear strength and both transverse reinforcement and column axial force, the effects of those parameters are included in the new estimation model. The new model is applied to the specimen database and the resulting estimates are compared to those by the current ACI and AIJ codes. Results showed that estimation of shear strength by the new model is much improved by all these modifications.