Comparison of Refined Numerical Modeling for Substandard Beam-Column Joints

Advanced numerical modeling for reinforced concrete structures is nowadays available. Nevertheless, reproducing the non - linear behavior of substandard beam - column joints is still a challenging task. Indeed, difficulties arise even more in capturing the con tribution of different nonlinear mechanisms (and their mutual effects) on the global cyclic response. This paper deals with the advanced numerical modeling of substandard reinfor ced concrete beam - column joints designed by reinforcement details non - conformi ng to current seismic codes. Experimental data from the different testing program s on joint subassemblies characterized by lack of transverse reinforcement in the joint, low strength concrete and plain round/deformed bars were collected from available literature studies. Refined numerical models, which were developed in VecTor2 and ATENA Science finite element method (FEM) software, are investig ated in detail to identify the factors affec ting the overall response. T wo different modeling strategies and their results are closely compared. Th e advantages - disadvantages, difficulties in implement ing the numerical model and their capability to capture the experimental behavior are discussed in detail . A focus on the influence of the modeling assumption on the joint panel shear behavior and the bond - slip of longitudinal reinforcements is provided. Practical suggestions were given to drive the structural engineers in developing efficient and reliable numerical models for substandard RC joints.