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Recent literature emphasized the scarcity of information on the shear behavior of fiber-reinforced polymer (FRP) reinforced concrete short beams and the need to develop sufficient experimental data in this area. The present study responds to this need by conducting shear force testing on eight concrete short beams reinforced with carbon-fiber-reinforced polymer (CFRP) and four control concrete beams reinforced with steel. To ensure a shear failure, all tested beams were reinforced with only bottom longitudinal reinforcement and no web reinforcement was provided. The crack pattern, reinforcement strain, mode of failure, and shear strength and deflection of tested beams were studied. The influence of the shear span to effective depth ratio, a/d, beam effective depth, d, longitudinal reinforcement ratio, ρ, and concrete compressive strength, f ′c on the shear behavior of CFRP-reinforced concrete short beams was examined. It was observed that the experimental parameters investigated had a significant effect on the shear strength and deflection of tested beams. It was also found that the strut-and-tie method more accurately predicts the shear strength of steel-reinforced concrete short beams than it does for similar CFRP-reinforced beams and, thus, needs to be modified to be applicable for reinforced concrete beams with FRP reinforcement.

The use of sustainable technologies such as supplementary cementitious materials (SCMs), and/or recycled materials is expected to positively affect the performance of concrete mixtures. However, it is imperative to qualify and implement such mixtures in practice, if the required specifications of their intended application are met. This paper presents the results of a laboratory investigation of self-consolidating concrete (SCC) containing sustainable technologies. Twelve mixes were prepared with different combinations of fly ash, slag, and recycled asphalt pavement (RAP). Fresh and hardened concrete properties were measured, as expected the inclusion of the sustainable technologies affected both fresh and hardened concrete properties. Analysis of the experimental data indicated that inclusion of RAP not only reduces the ultimate strength, but it also affected the compressive strength development rate. The addition of RAP to mixes showed a consistent effect, with a drop in strength after 3, 14, and 28 days as the RAP content increased from 0 to 50 %. However, most of the mixes satisfied SCC fresh properties requirements, including mixes with up to 50 % RAP. Moreover, several mixes satisfied compressive strength requirement for pavements and bridges, those mixes included relatively high percentages of SCMs and RAP.

This article investigates the shear behavior of deep concrete beams reinforced with glass fiber reinforced polymer for flexure and without shear reinforcement. A total of 13 beams were tested under four-point loading until failure. Nine of which reinforced with glass fiber reinforced polymer bars and four with steel bars. The ultimate shear capacity along with the load-deformation relationship of all beams was studied. The effects of the shear span to depth ratio a/d, reinforcement ratio , beam effective depth d, and concrete compressive strength on the ultimate shear capacity and mode of failure of all beams were also investigated. Results show that the stiffness of steel-reinforced concrete beams (slope of the ascending portion of load-deflection curve) is higher than that of beams reinforced with fiber-reinforced polymer bars as expected, due to the low axial stiffness of the fiber-reinforced polymer material. A slight variation in the ultimate shear capacity was noticed but no clear trend was observed. In addition, beams reinforced with fiber-reinforced polymer exhibited larger deformation at their ultimate failure load, after which a sudden failure occurred especially for beams having high shear capacity.