Seismic Performance of GFRP-RC Exterior Beam–Column Joints with Lateral Beams

Abstract

In the past few years, some experimental investigations have been conducted to verify seismic behaviour of fiber reinforced polymer reinforced concrete (FRP-RC) beam-column joints. Those researches were mainly focused on exterior beam-column joints without lateral beams. However, lateral beams, commonly exist in buildings, can significantly improve seismic performance of the joints. Moreover, the way the longitudinal beam bars are anchored in the joint, either using headed-end or bent bars, was not adequately addressed. This study aims to fill these gaps and investigate the shear capacity of FRP-RC exterior beam-column joints confined with lateral beams, and the effect of beam reinforcement anchorage on their seismic behaviour. Six full-scale exterior beam-column joints were constructed and tested to failure under reversal cyclic loading.Test results showed that the presence of lateral beams significantly increased the shear capacity of the joints. Moreover, replacing bent bars with headed-end bars resulted in more ductile behaviour of the joints.iii

Internal and External Reinforcement of Concrete Members by Use of Shape Memory Alloy and Fiber Reinforced Polymers under Cyclic Loading—A Review

“…Similar to the latter reference, Ghomi and El-Salakawy [12] performed experiments on six full-scale BCJs reinforced internally with GFRP bars and stirrups under seismic loading. The joints had lateral beams on all four sides of the column.…”

“…Numerous researchers have worked on the use of FRP sheets as external reinforcement for confinement, shear, and flexural strengthening [1,2,3,4,5,6]. However, only few researchers have started to work on the concept of using FRP as internal reinforcement for BCJs, which are critical components, and their failure could result in the total collapse of the structures [7,8,9,10,11,12].…”

Behavior of Structural Concrete Frames with Hybrid Reinforcement under Cyclic Loading

“…In addition, it was concluded that increasing the beam reinforcement ratio can enhance the ability of the joint to dissipate the seismic energy through utilizing the inelastic behavior of concrete. Ghomi and El-Salakawy [19,20] investigated the seismic behavior of the RC beam-column joints with GFRP reinforcement. It was inferred that the axial load level of the columns greatly affects the earthquake's behavior of the RC beam-column joints with GFRP reinforcement.…”

Discussion of “Seismic Behavior of GFRP-Reinforced Concrete Interior Beam–Column–Slab Subassemblies” by Shervin K. Ghomi and Ehab El-Salakawy

“…1 shows the residual drift ratio of two specimens (G-SL and G-XX joints) at the maximum load. Since the authors did not include the second-phase cyclic load-drift curves of the G-SL and G-XX specimens, the discussers included the residual drift ratios of the other two FRP-RC joints that were experimentally tested by Ghomi and El-Salakawy (2018) for comparison. It should be noted that the additional two joints were tested in two loading phases, similar to the specimens in the reference paper.…”