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Over the previous three decades, researchers have dedicated significant efforts towards the advancing of glass fiber-reinforced polymer (GFRP) bars, aiming to address the challenges arising from corrosion in traditional steel reinforcement bars. This study intended to find the most efficient relation to compute compression load capacity for concrete columns of circular sections reinforced with GFRP through surveying equations from previous research and comparing the relations of the most popular GFRP codes (JSCE, AS, CSA, and ACI). The statistical analysis of the equations depends on a comparison of practical and theoretical load capacities, Young's modulus, compressive concrete strength, ratios of longitudinal and both types of transverse reinforcement, spirals, and hoops. The results of CSA and AS were close to each other, and they were better than those of JSCE and ACI regarding being efficient, safe, and consistent. In addition, JSCE demonstrated a high level of conservative in all the studied parameters, followed by the ACI, while the CSA and AS showed very low conservative rates. Furthermore, the AS showed superiority in all the studied parameters. In terms of statistical metrics, the AS exhibited a very low error rate. It was concluded that the AS relation is the most efficient and superior relation for computing the axial load carrying capacity (ALCC) of all the studied parameters, followed closely by the CSA code equation, and with a slightly larger margin, the ACI code equation then JSCE code equation with a slightly very large margin.

Reinforced concrete deep beams are structural members having depth much greater than normal in relation to their span, while the thickness in the perpendicular direction is much smaller than either span or depth. The strength of deep beams is usually controlled by shear, rather than flexure. In this study, the previous researches related to reinforced concrete deep beams will be reviewed. These researches approximately started in the second half of the past century. Large numbers of researchers studied the behavior of concrete deep beams and the determination of their capacity. Some of these researches are experimental investigations carried out by testing a number of deep beams with variation in some parameters, while the others are theoretical to estimate deep beam capacity by developing some theories and suggestion of equations for calculating its capacity and comparisons were made with those adopted by some codes. Because of the large number of these researches, their review requires large part of this study, and because the prior studies elaborately reviewed the pioneer researches, only the researches made since year 2000 will be reviewed in this study.

Glass-fiber-reinforced polymer (GFRP) bars reinforced concrete beams and fortified by carbon-reinforced polymer (CFRP) slips can provide high resilience, high sustainability and reasonable strength for a building scheme. Few experiments contract the combined operation of these products and this was the undertaking's fundamental impetus. The presented study includes an extensive and interesting experimental analysis of the flexural efficiency of reinforced concrete beams GFRP bars and fortified by CFRP sheets. A total of ten GFRP reinforced concrete beams are equipped, experienced and subject to frequent loading series using a four-point bending expedient to complete a catastrophe analysis. The main parameters were GFRP reinforcement ratio and number of CFRP sheets. The central deflection, crack size and concrete strains of the verified beams were verified and contrasted. In this study, the feasibility of using particle image velocimetry (PIV) to detect cracks established in reinforced concrete beams were discovered so that a practical effect can be suggested. The PIV technique has been realistic for analyzing the surface field movement and strain. The test results discovered that the crack sizes and central deflection were considerably decreased by increasing the reinforcement ratio and number of CFRP layers, results characterized that due to its lower cost and strong capacity to observe cracking efficiency, PIV method can be used as a substitute for traditional measuring methods during specific structural tests, exclusively in bending tests.

This paper presents an experimental investigation consisting of casting and testing twelve rectangular simply supported reinforced concrete deep beams. Three of the tested beams are made with conventional concrete (CC), three with ultra-high performance concrete (UHPC) and six as hybrid beams of the two concrete (UHPC &CC). UHPC is used in compression in the hybrid beams. The effect of these parameters on the behavior of the test beams included deflection, failure mode, and ultimate loads is investigated. Experimental results generally show that stiffer load-deflection behavior is obtained with the increase of UHPC layer thickness (hR/h) and steel fibers volumetric ratio (Vf) for hybrid beams with UHPC in compression.

The solution of using glass fiber reinforced polymer (GFRP) bars, as reinforcement in concretestructures to overcome the problems created by steel reinforcement, is now widely accepted because of both its low cost and good results shown by large investigation efforts. In this paper twelve tests had beenconducted on reinforced concrete column specimens of (120 x 120 x 1000)mm effective dimensions) equally enlarged from both ends for the purpose of applying eccentric load, three specimens were made of high strength concrete, reinforced with traditional deformed steel bars and stirrups to be considered as references, while the remaining nine specimens were of high strength concrete with 0% , 0.5% , 1.0% steelfiber, reinforced longitudinally with GFRP bars and wrapped with carbon fiber reinforced polymer(CFRP) textile replacing the steel stirrups. In addition to the similarity in behavior under load and in the failure patterns of the specimens reinforced with GFRP bars and the specimens reinforced withtraditional steel, the results show that Steel reinforced columns has 13% higher ultimate load than corresponding GFRP reinforced columns.

This paper presents an experimental investigation on shear behavior of Glass Fiber Reinforced Polymer (GFRP) reinforced high strength concrete beams externally strengthened in shear using Carbon Fiber Reinforced Polymer (CFRP) with various configurations: full side sheets, U-strips, vertical side strips and diagonal side strips; and three steel fiber ratios (0%, 0.5% and 1%). Results show that using GFRP bars as tension reinforcement instead of traditional steel bars slightly increases ultimate load but shows lower stiffness. Although internal steel stirrups are still the most effective way to enhance shear capacity of concrete beams, externally bonded CFRP U-strips can also be an effective alternative for durability and/or architectural considerations with about 85% strength efficiency and comparable load-deflection behavior. A combination of U-strips and sufficient amount of steel fiber is shown to perform better than steel stirrups in terms of increasing carrying capacity and decreasing deflections of GFRP reinforced concrete beams.

The experimental work of this study includes testing sixteen reinforced concrete one-way slabs cast using high strength self-compacting concrete (HSSCC) with using steel fibers to evaluate their flexural behavior and strength. The slabs were subjected to concentrated transverse loads (loads were distributed across the entire width of the slab) at the third points. All tested slabs have dimensions of 1000×450×50 or 70 mm. The parameters considered are slab thickness, steel reinforcement ratio (ρ) and steel fiber volumetric ratio (Vf). The effect of these parameters on the behavior of the tested slabs included investigation of deflection, failure mode, and ultimate loads. Two different failure modes were predicted either flexural tension mode or flexural shear mode or a combination of these two.