Title Impact of Interior Beam-Column Joint Aspect Ratio on Shear Resistance in Reinforced Concrete Structures
Authors 조민수(Jo, Min-Su) ; 김동환(Kim, Dong-Hwan) ; 김형국(Kim, Hyeong-Gook) ; 이정윤(Lee, Jung-Yoon) ; 김길희(Kim, Kil-Hee)
DOI https://doi.org/10.5659/JAIK.2026.42.4.339
Page pp.339-346
ISSN 2733-6247
Keywords Aspect Ratio; Interior Beam-Column Joint; Joint Shear Crack Angle; Shear Strain; Shear Stress
Abstract In reinforced concrete moment-resisting frames, beam-column joints are critical structural elements subjected to very high shear forces under lateral loads, such as earthquakes. These connections transfer loads between upper and lower columns, anchor beam longitudinal reinforcement, and distribute stiffness throughout the frame. Failure of these joints can lead to the collapse of the entire structure, making their behavior essential for seismic design. Current seismic design codes evaluate connection shear strength using a limited set of parameters, including concrete compressive strength, confinement effects, and effective joint area; however, the impact of the aspect ratio, defined as the ratio of beam depth to column depth, is not addressed. In this study, four reinforced concrete interior beam-column joints were fabricated with aspect ratio as the primary variable and tested under cyclic loading until joint shear failure occurred before yielding of the beam longitudinal reinforcement. Experimental results showed that shear deformation in the joint panel region increased with increasing aspect ratio. In contrast, joint shear stress decreased, and when the aspect ratio exceeded 1.0, joint shear strength fell below the values specified in current design codes.