Title:
Seismic Behavior of Glass Fiber-Reinforced Polymer and Steel-Reinforced Circular Columns
Author(s):
Jahanzaib and Shamim A. Sheikh
Publication:
Structural Journal
Volume:
123
Issue:
2
Appears on pages(s):
211-224
Keywords:
circular columns; comparison; fiber-reinforced polymer (FRP); longitudinal bars; seismic loading; transverse bars
DOI:
10.14359/51749173
Date:
3/1/2026
Abstract:
The paper presents a comparative study on the seismic behavior of circular columns reinforced with glass fiber-reinforced polymer (GFRP) and steel. The study specifically investigates the influence of replacing steel bars with GFRP bars on columns’ seismic response. All the studies summarized in this paper were conducted at the University of Toronto, Toronto, ON, Canada. Results from the tests of 24 columns (all having 356 mm [14 in.] diameter and tested in a similar manner) from three different studies are closely analyzed to compare their responses. Based on the experimental results, it is found that replacing steel spirals with GFRP spirals did not result in substantial variation in the seismic performance of columns. Both types demonstrated similar ductility parameters and drift ratios when similar amounts of spirals were used at comparable pitches. Likewise, columns with steel longitudinal reinforcement and GFRP longitudinal reinforcement achieved similar deformation capacities but with lower strength and stiffness.
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