The seismic performance of new detailing for RCS connections

• RC columns –Steel beam (RCS) connections with standard and proposed detail are tested
• Self consolidated concrete used in the experiments showing good effectiveness
• Results show the effectiveness of new detailing.
• New joint details are simulated and compared with the experiment.
• Effects of different part of joint detail in the connection performance are studied.
• Additional bearing plates (ABPs) significantly increase the RCS connection capacity.

Over the past few decades considerable experimental and numerical studies have been conducted on the Reinforced Concrete columns to Steel beams (RCS) connections. Most of those researches have focused on studying the joint failure modes and ultimate joint strength of specimens utilizing strong beams and columns with weak joints. In this paper, two interior RCS connections were designed based on the Strong Column–Weak Beam (SCWB) criterion. Both specimens were tested under quasi-static reversed cyclic loading. The tested specimens were modeled by a finite element method, which verified with experimental results. Several models with different joint details were investigated using the verified FEM. Lateral load–story drift response, vertical bearing stresses, joint shear forces, shear strains at the joints, and axial stresses of the joint stirrups were studied in those models. The results indicated that the performance of models directly depends on joint detailing, effectiveness of shear keys, and the amount of confinement provided for a joint region.