Effect of Slenderness Ratio on Glass Fiber-Reinforced Polymer-Reinforced High-Strength Concrete Columns

This paper presents the results of eight large-scale high-strength concrete (HSC) columns reinforced internally with glass fiberreinforced polymer (GFRP) bars and spirals. The effects of the slenderness ratio and the eccentricity-to-diameter ratio (e/D) on the behavior of HSC columns that meet the minimum code requirements are evaluated. Additionally, the column behavior was investigated under pure flexural loading. Test results indicated that increasing the e/D or the slenderness ratio resulted in a decrease in the axial and lateral stifiness and the axial capacity of the HSC columns. All tested columns exhibited a material-type failure, which is characterized by the crushing of concrete. Furthermore, compressive strains measured in the GFRP bars indicated their contribution to the column axial capacity. In addition, an interaction diagram was developed and compared to the predictions of the available codes and guidelines. Keywords: bending; eccentric loading; glass fiber-reinforced polymer (GFRP) bars and spirals; high-strength concrete (HSC); short columns; slender columns.