Numerical study on shear strength of GFRP-RC T-Joints

This paper presents the numerical modeling and behavior of glass fiber-reinforced polymer (GFRP) reinforced concrete (RC) exterior beam-column joints (T-joints) under cyclic loading. The numerical modeling was implemented on four tested RC T-joints (two steel-RC and two GFRP-RC) in the finite element software ATENA. The numerical model was verified against the results of previous experimental studies. The validated numerical model was used to investigate the effects of the flexural reinforcement ratio of the beam, the compressive strength of concrete, axial load on the column, joint aspect ratio, joint confined area by lateral beams, and joint configurations on the shear strength and load–displacement envelope curves of the GFRP-RC T-joints. The numerical study results indicated that increasing the flexural reinforcement ratio of the beam by up to 1.77% increased the strength and stiffness of the GFRP-RC T-joints. The GFRP-RC T-joints were able to resist joint shear stress by up to 0.85fc′, and higher joint aspect ratios led to premature failure of the GFRP-RC T-joints. The GFRP-RC T-joint with 54% joint confined area by lateral beam attained 33% higher strength than the unconfined (no lateral beam) GFRP-RC T-joint.