Rendy Thamrin

Strain Distribution on Reinforcement of Concrete Beams Reinforced with Glass Fiber Reinforced Polymer (GFRP) Bars

This paper presents a part of the results from an experimental study of strain distribution on reinforcement of concrete beams reinforced with glass fiber-reinforced polymer (GFRP) bars. Under static loading conditions, eight concrete beams reinforced with GFRP bars were tested and as comparison eight beams with steel reinforcement were also tested. All of the beams were prepared with varying ratios of longitudinal reinforcement bars and stirrups. The effect of shear span-effective depth ratio on strain distribution of longitudinal reinforcement was also observed. Furthermore, the behavior of strain on stirrups due to different materials of longitudinal reinforcement was also discussed in this report. The test results show that the ratio of longitudinal reinforcement significantly influence the strain distributions on reinforcement where the beams with higher ratio exhibit higher strain. Moreover, it was also obtained that the different types of longitudinal reinforcement considerably influences the strain behavior on stirrups as higher strain was observed in beams reinforced with GFRP bars.

Effect of Longitudinal Reinforcement Ratio on Shear Capacity of Concrete Beams with GFRP Bars

This paper evaluates the shear capacity of concrete beams longitudinally reinforced with glass fiber-reinforced polymer (GFRP) bars. All beams were provided with steel stirrups as shear reinforcement within shear region with spacing, 150 mm. The effect of longitudinal reinforcement ratios, ρ f is discussed and compared with conventional beams reinforced with steel. The test results were compared with predictions recommended by ACI 440.1R-06 design guidelines and by other references. Other performance in terms of tensile strength and stresses in reinforcement bars was analyzed. Based on the findings of test results, it is shown that the shear resistance of GFRP RC beam is influenced by modulus elasticity of GFRP bars that resulted in low shear strength compared to conventional beams. Moreover, due to specific properties of GFRP materials, shear behavior of beams with GFRP bars is different to that of beams with steel. The current design guideline (ACI 440.1R-06) was found to be very conservative compared with experimental results.

Shear Capacity of Non-Metallic (FRP) Reinforced Concrete Beams with Stirrups

This study presents test results of simply supported concrete beams longitudinally reinforced either by steel or glass fiber-reinforced polymer (GFRP). A total of sixteen large-scale concrete beams with steel stirrups were constructed and tested under four-point monotonic loading until failure. Half of the beams were longitudinally reinforced with GFRP bars, while the other half was reinforced with conventional steel bars as control specimens. To examine the shear behavior of the GFRP reinforced concrete (RC) beams, the main parameters investigated in the study included shear span-effective depth ratios, longitudinal reinforcement ratios and stirrup ratios. Two modes of failure, namely flexure and shear were observed. Due to low modulus elasticity of FRP bars, it was found that lesser shear strength resulted in concrete beams reinforced with GFRP bars compared to beams reinforced with steel bars. Moreover, the influence of the shear span-effective depth ratios and longitudinal reinforcement ratios significantly affect the distribution of internal forces in GFRP reinforced concrete beams. The test results correlated well with the prediction values provided by standard codes and design guidelines except in the case of GFRP reinforced concrete beams failed on shear.