Performance of SRC column-RC beam joints under combined axial and cyclic lateral loadings

• Published in: Engineering structures 2022-06, Vol.260, p.114218, Article 114218
• Main Authors: Gautham, A., Sahoo, Dipti Ranjan
• Format: Article
• Language: English
• Subjects: Axial loads; Beam-column joints; Beam-columns; Columnar structure; Combined loading; Concrete; Concrete columns; Concrete structures; Configurations; Crack propagation; Cyclic loads; Lateral displacement; Lateral loads; Quasi-static testing; Reinforced concrete; Reinforcing steels; Rotation; Seismic activity; Seismic behavior; Steel; Steel reinforced concrete; Stiffeners; Structural steels
• ISSN: 0141-0296; 1873-7323
• DOI: 10.1016/j.engstruct.2022.114218

•Two different detailing schemes have been studied for the exterior RC beam-SRC column joints.•The key parameters varied are the anchorage length of beam longitudinal bars and the transverse stiffeners.•Moment-rotation characteristics are developed for exterior RC beam-SRC column joints.•A new detailing of the composite connection between the SRC column and RC beam has been proposed. Strong column-weak beam behavior of a concrete structure with reinforced concrete (RC) beams and steel reinforced concrete (SRC) columns can only be ensured during a seismic event if the premature failure of beam-column joints could be avoided. The RC beam-SRC column joints, however, require special design and reinforcement detailing due to the presence of structural steel sections in the columns. Two different detailing schemes have been explored in this study for the exterior RC beam-SRC column joints. The key parameters varied in these detailing schemes are the anchorage length of beam longitudinal bars and the provision of transverse stiffeners in the structural steel sections. Three large-scale test joint specimens have been tested under the combined axial load and the varying lateral cyclic displacements. The crack propagation patterns, hysteresis behavior, moment-rotation characteristics, lateral stiffnesses, and joint shear-distortion behaviors of the composite specimens have been compared with the RC specimen to verify the suitability of the studied configurations. The experimental moment-rotation behavior of the test specimens has been compared with the theoretical moment-rotation curves derived using the current code provisions. Finally, the recommendations for the suitable configuration of the composite connection between the SRC column and RC beam have been proposed.