Short Concrete Columns Reinforced with GFRP Rebars under Eccentric Loading

Abstract

In this paper, the compressive performance of short concrete columns reinforced with glass fiber-reinforced polymer (GFRP) composite rebars is evaluated. A total of fourteen 500 mm long concrete specimens with square cross-section (150×150 mm) were prepared and tested under concentric and eccentric compressive loading up to failure. Nine of the specimens were reinforced with six GFRP rebars (16 mm diameter), longitudinally. Different eccentricities, namely, 0, 10, 20, and 30 percent of the width of the specimens were considered. Strain of GFRP rebars were monitored during the tests to evaluate the usable level of strain and mode of failure of rebars. It was observed that the GFRP rebars were able to withstand the peak concentric and eccentric loads without crushing and local buckling. It was concluded that the maximum usable strain of the GFRP rebars in compression was larger than the ultimate compressive strain of concrete, 0.0035, defined by CSA A23.3 and the compressive contribution of GFRP rebars in column capacity is not negligible. This is an ongoing research and more results regarding compressive behavior of GFRP rebars and their contribution to the axial-bending interaction diagram will be presented at the time of the conference.