Concrete Columns Reinforced Longitudinally and Transversally with Glass Fiber-Reinforced Polymer Bars

Using fiber-reinforced polymer (FRP) reinforcing bars as the main reinforcement for concrete structures in harsh environments is becoming a widely accepted solution to overcome the problem of steel corrosion. Due to the relatively lower cost of glass FRP (GFRP) bars compared to the other commercially available FRP bars, the use of GFRP bars in reinforced concrete (RC) structures has been widely investigated. This paper presents an experimental study of the behavior of 350 x 350 mm (13.78 x 13.78 in.) cross-section concrete columns reinforced with GFRP bars under concentric loading. The effects of key variables, such as tie configuration, tie spacing, and spoiling of concrete cover were studied. The columns reinforced with GFRP withstood loads similar to or higher than the columns reinforced with steel. The mechanism of failure was explained. Gains in strength and ductility were recorded for the concrete cores of well-confined columns.