Understanding the behaviour of modern reinforced concrete beam-column joints towards the development of a simplified structural model

2022-7
Şahutoğlu, Orhan
Beam-Column joints in reinforced concrete structures (RC) are important elements that connect beams and columns. For the proper transfer of lateral forces along a continuous load path, the integrity of these joints and sufficient strength are crucial. Modern seismic design philosophies dictate these joints to be designed and reinforced with the required joint shear reinforcements. Extreme principal compression stresses in these joints might cause joint shear failure even when the joints are properly reinforced considering capacity design principles. This emphasizes the significance of the axial load levels in the behavior of RC beam-column joints, which are currently being overlooked. This problem is strongly relevant to the sustainability of the modern RC structures and their expected seismic viii performance since almost all existing RC buildings are susceptible to this weakness with enough axial compression levels in column. In this study, a previously developed simplified beam-column joint model, defined as an axial load-moment (N-M) interaction envelope, is implemented in the non-linear static and dynamic analyses of a modern building (with/without vertical accelerations) that suffered joint shear damage. The study aims to utilize the model in its simplest form in a widely used structural analysis software, which is expected to be used by practicing engineers. The accuracy of the joint model in simulating the seismic response is determined by comparing the analysis findings with the observations from real building damage. The model accurately represents joint shear behavior in non-linear static and non-linear dynamic analyses with varying axial load levels.

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Citation Formats
O. Şahutoğlu, “Understanding the behaviour of modern reinforced concrete beam-column joints towards the development of a simplified structural model,” M.S. - Master of Science, Middle East Technical University, 2022.