EFFECT OF COMBINED SHEAR, BENDING AND LOW AXIAL LOAD ON BEHAVIOR OF CONCRETE BEAMS REINFORCED WITH GLASS FIBER-REINFORCED POLYMER BARS

Abstract

This research's main objective was to investigate the effect of combined bending and shear behavior of the concrete beams reinforced with glass fiber reinforced polymer (GFRP) bars subjected to low axial load less than 10% beams axial capacity. Analytical and experimental study was performed for nine full-scale reinforced concrete beam specimens of size 330 x 430 x 3100 mm casted using sand coated GFRP bars with different reinforcement ratios of 1.7, 2.5 and 3.3%. The specimens were tested under four-point bending, and low axial compressive loading was applied at beam both ends. The analytical model was developed using PTC MATHCAD Prime to analyze the beams’ behavior, verified by the experimental investigation. The analytical study results of the beam interaction diagram from all cases show that moment carrying capacity of the beams typically decreases by adding axial load in the range of 2.0 to 4.0% of the axial capacity of the sections.