ٍسندس علي حسين شكر

Steel-fibre reinforced polymer (FRP) composite bar (SFCB) is a novel form of rebar. The main technique for SFCB manufacturing, which is described briefly in this paper, is a manual technique, and this study cast eight slabs using this procedure to investigate the flexural behavior of SFCB-reinforced concrete slabs by comparing them with concrete slabs reinforced with ordinary steel bars. The study included an investigation of changes in the thickness of slab, the effects of the CFRP sheet length wrapped around the steel bars, and concrete compressive strengths. The outcomes showed that, increasing the slab thickness from 80 to 100 mm led to an increase in the ultimate load capacity of 55%, while utilising SFCB reinforcement enhanced the ultimate load capacity, with maximum percentage increases ranging from 23% to 41%. Furthermore, the results showed that replacing NC with RPC offered slight enhancements in the ultimate load: this was about 12% in the control slab, while when SFCB was used, the improvement was 16%. Finally, a length of reinforcement two-thirds of the full length of the bar was found to be the optimum length when used for strengthening. Within this paper, the methodology and results are first outlined, then a brief conclusion offered with regard to the investigation overall.

A hybrid rebar Steel Fibre Composite Bar (SFCB) is a composite rebar made of a conventional steel bar wrapped by Carbon fibre-reinforced polymer (CFRP) sheets. The characteristics of this hybrid rebar are a combination of the advantages and attributes of both materials was made from. This paper introduces the manual techniques that were used to produce this hybrid rebar, which has a conventional round steel bar inside its core and CFRP outside. Then, the flexural behaviour of the Hybrid rebars used to reinforce Concrete slabs was tested, evaluated and compared with the slabs reinforced by conventional steel bars. The experimental works also test the effects of the thickness of the slab, length of the CFRP sheet wrapped around the steel barn different compressive strengths (Normal concrete and Reactive Powder concrete). The test results showed that the bars, hybrid rebars percentage used, and using two types of concrete with increasing the thickness of slab model from 100 to 120 mm of the control slabs, caused increasing in the ultimate distributed lead by 10.41% besides the changing of concrete type of the control slabs from the normal concrete to Reactive Powder Concrete increased the ultimate distributed load to reaches 12.5% The experimental results indicated also that the that wring hybrid rebar as internal reinforcement improved that ultimate distributed load capacity by approximately (28.3%, 37.5% to 40.74%) in comparison with the reference slabs of the specimen specimens with thickness of 120mm, 100mm and the RPC slabs respectively. Regarding the first crack load, no change was recorded in first cracking load in comparison with control specimen with a thickness of 100 mm, while, a noticeable increasing of the load that recorded the first cracking in comparison with control specimens, for the specimens with a thickness of 120 mm and RPC specimens, the increasing came as 25% compared with the reference specimens. No influence on the maximum deflection was indicated for all specimens. The specimens with an internal hybrid reinforcement system and the Hybridisation length of (1050 mm), which represents the whole length of the bar, showed the ultimate load capacity

The Steel-fiber reinforced polymer (FRP) composite bar (SFCB) is a recently proposed bar, it has a steel inner and an exterior layer of FRP, and an adhesive resin to bond the two materials. The SFCB bar used in this paper was made by using a handmade technique; this technique includes a manufacturing procedure that was described in this paper. SFCBs were tested using the standard uniaxial tensile test (ASTM A370) to figure out their mechanical properties and stress-strain relationship and compare them with the normal steel bars. Moreover, the bonding test was conducted to comprehend the bonding performance of SFCB in the concrete and to compare it with the normal steel performance, the bonding test was conducted according to ACI 440.3R-12. The experimental results illustrated that the values of yielding and ultimate tensile strengths of SFCB were slightly less than that of the conventional steel with percentages of 4% for both, the modulus of elasticity values which were found theoretically in good agreement with the test results values, the behavior of SFCB stress-strain curve was slightly different than the conventional steel behavior, with a stable post-yield modulus. Also, the results showed that the SFCB/Steel (SFCB/Steel) ratio between the bond strength of SFCB and the bond strength of steel bar was approximately 0.86, which means that the SFCB had lesser bond strengths than the normal steel with a percentage of 14%, the results also showed that the SFCB had less slip than the steel bar with a percentage of 10%.

https://uokufa.edu.iq/archives/131089