Predicting shear strength of RC interior beam–column joints by modified rotating-angle softened-truss model

A theoretical model is presented for analysing the shear behaviour and predicting the shear strength of reinforced concrete (RC) interior beam–column joints. The model presented is referred to as the modified rotating-angle softened-truss model (MRA-STM), which is modified from the rotating-angle softened-truss model and the modified compression field theory. In the proposed methodology, the RC interior joint is treated as an RC shear panel that is subjected to vertical and horizontal shear stresses transferred from adjacent columns and beams. Employing the deep beam analogy, the characteristic strut and truss actions typical in beam–column joints are represented by the effective transverse compression stresses and the softened concrete truss in the model. Sixteen RC interior beam–column joints were subsequently analysed with the proposed model. Shear strengths of the RC interior beam–column joints predicted by the proposed model show very good agreement with the experimental results.