Title:
Retrofitting Exterior Reinforced Concrete Beam-Column Joints with Transverse Beams Using Fiber-Reinforced Polymer
Author(s):
Altho Sagara, Iswandi Imran, Erwin Lim, and Patria Kusumaningrum
Publication:
Structural Journal
Volume:
123
Issue:
1
Appears on pages(s):
119-130
Keywords:
exterior beam-column joint; fiber-reinforced polymer (FRP); joint hoops; joint shear strength; retrofitting
DOI:
10.14359/51749100
Date:
1/1/2026
Abstract:
During past earthquakes, failures of beam-column joints have commonly been observed on the exteriors of buildings. However, only one side of these joints can be retrofitted because of the presence of beams on the other three sides. Therefore, this study aims to test four exterior beam-column joints with transverse beams, leaving the rear side as the only viable location for placing fiber-reinforced polymer (FRP) laminate. All four test specimens were designed with insufficient joint shear strength, as determined by ACI 318-19 equations, while satisfying the criteria for a strong-column/weak-beam mechanism and sufficient development length for bar anchorage. A total of two un-retrofitted specimens, with and without joint hoops, were constructed as controls. Subsequently, two similar specimens were retrofitted by applying FRP laminate on the rear side. The results show that sufficient FRP laminate can enhance the seismic performance of joints in terms of deformability, energy dissipation, and failure delay.
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