This paper reports on the efficiency of fabric-reinforced cementitious matrix (FRCM) in enhancing the flexural capacity and deformational characteristics of RC beams. In the main experimental part of the paper, 12 RC beams, 2,500 mm long, 150 mm wide, and 260 mm deep, were fabricated. The beams had two different steel reinforcement ratios, namely, ρsD12=0.72% and ρsD16=1.27%, representing typical underreinforced beam sections. The strengthened beams utilized two FRCM types, carbon and polyparaphenylene benzobisoxazole (PBO) FRCM systems. In the second part of the work, tensile material characterization tests were performed on the FRCM coupons to determine the tensile characteristics of the FRCM composites. The beams were tested in flexure under four-point loading until failure. Two beams without FRCM strengthening were used as a benchmark. Six beams were externally strengthened using one, two, and three layers of carbon FRCM system. Four beams were strengthened with one and two layers of PBO FRCM ...

This paper reports on the shear behavior of concrete beams reinforced with basalt fiber-reinforced polymer (BFRP) bars. In this study, 10 reinforced concrete beams with no transverse reinforcement, including 2 beams reinforced with longitudinal steel bars, were constructed and tested until failure. The test variables were the longitudinal reinforcement ratio and the span-to-depth ratio of the beams. The test results were compared with predictions of different available codes and design guidelines. Shear design equations of the CAN/CSA-806-12 code and the JSCE-97 guidelines provided accurate predictions. However, the predictions of CAN/CSA-806-12 were not conservative in some cases, whereas those of the ACI-440.1R-15 and the CAN/CSA-S6-10 were conservative. The test results were combined with the experimental results of a large database, including 75 beams and one-way slabs reinforced with carbon, glass, aramid, and BFRP bars. The behavior of beams reinforced with BFRP bars was quite similar to tha...

Twelve concrete columns reinforced longitudinally with fiber-reinforced polymer (FRP) bars were tested under both concentric and eccentric loadings. The investigated parameters were the type of the FRP bar, the longitudinal reinforcement ratio, and the load eccentricity-to-width ratio. The test results showed that the columns reinforced with basalt-FRP (BFRP) and glass-FRP (GFRP) experienced similar load-carrying capacity with a difference of less than 5%. Both types of columns attained lower ultimate capacity than their steel-reinforced counterparts. The contribution of the GFRP and BFRP bars to the ultimate capacity of the columns was similar, approximately 11% of the capacity, as compared to 31% for the steel bars. The effect of increasing the reinforcement ratio on the capacity was more pronounced in the eccentric FRP-reinforced concrete (FRP-RC) columns than the concentric ones. The analytical investigation showed that ignoring the strength contribution of the FRP bars, as recommended by most of the current codes and design guidelines, would result in conservative predictions. It also showed that current Canadian design code recommendation limiting the strains in FRP bars in compression to 2,000 µɛ yielded reasonable predictions of the column capacity.

This paper presents the test results of a durability study on a novel basalt fiber-reinforced polymer (BFRP) bar-anchor system. The BFRP bars were exposed to saline and alkaline solutions for 10 weeks before being anchored and tested under static and fatigue loading. Unconditioned basalt, glass, and carbon specimens were also tested and served as controls. Regardless of the fiber material, all the bar-anchor systems withstood their ultimate tensile loading with no sign of slippage or premature failure in the anchor zones. Conditioning of the BFRP bars in saline and alkaline solutions resulted in 7 and 9% decreases, respectively, in the systems’ tensile capacity. A decrease of 11% in the modulus of the alkali-conditioned BFRP specimens was also observed. The fatigue test results showed that the fatigue life of the bar-anchor system was primarily affected by the applied stress range. In addition, continuous immersion of the BFRP bar in the alkaline solution increased its tendency to fracture prematu...

This paper presents results of finite element (FE) modeling and experimental testing of reinforced concrete beams strengthened in shear with fabric-reinforced cementitious matrix (FRCM). The studied parameters included the number of FRCM layers (one and two layers), matrix type (mortar and epoxy), and amount of internal stirrups (no stirrups and stirrups with spacings of 0.6d and 0.3d, where d is the depth of the tensile steel). Test results showed that the shear-strength gain after strengthening was in the range of 51–145%. The shear-strength gain decreased with an increase in the amount of internal stirrups. Doubling the number of FRCM layers resulted in a nonproportional increase in the shear strength. The use of epoxy adhesive rather than a cementitious mortar as a matrix insignificantly increased the shear-strength gain. The effect of increasing the amount of FRCM or varying the matrix type on the shear strength was less pronounced for the specimens with internal stirrups. The FE models devel...