Glue for optical fiber bonding.Figure eight. Schematic of optical fiber mounting.Polymers 2021, 13,9 ofFigure 9. Spare length supplied in optical fiber after each attachment to steel bar.three. Final results and Discussions 3.1. Failure Modes 3.1.1. Beam B-Con As a result of adequate shear spans, the behavior from the control beam was controlled by flexure. Flexural cracks were observed at pretty low loads, as shown in Figure 10. However, this was merely a transition from the uncracked to cracked concrete stage with no drop in strength. A further boost in load accompanied the spread and generation of new flexural cracks. Failure in the handle beam was observed at a 53 kN load, exhibiting huge flexural cracks (see Figure 11), at the same time as yielding with the Fluo-4 AM Technical Information bottom longitudinal steel bars and crushing on the concrete at extreme compression (see Figure 12). All round, the failure mode of beam B-Con was controlled by the tensile behavior on the longitudinal reinforcement at the tension face immediately after the look on the very first crack. Comparable failure modes have been reported in earlier research [35,36].Figure 10. Onset of flexure cracks at early load stage.Polymers 2021, 13,ten ofFigure 11. Final failure of control beam.Figure 12. Common crushing of concrete in all specimens.3.1.2. Beam B-01 Beam B-01 also exhibited hairline flexural cracks in the early load stage. This beam failed at a 66 kN load, exhibiting massive flexural cracks and yielding of longitudinal reinforcement. In contrast to the manage specimen, B-01 exhibited concrete compression. At failure load, rupture with the FRP was observed, reflecting that the capacity with the FRP composite was exhausted. Flexural cracks formed a wedge-shaped pattern within the vicinity on the FRP rupture, as shown in Figure 13. The formation of a wedge-shaped pattern was mainly due to the presence of the FRP composite as the tension side. As a result of the FRP composite, the crack width on the flexural cracks was small and there were few cracks having a huge crack width in the location on the FRP rupture. Additional, FRP de-bonding was observed slightly prior to its rupture.Polymers 2021, 13,11 ofFigure 13. FRP rupture and wedge formation at final failure of beam B-01.3.1.3. Beam B-02 The formation of flexural cracks in the early load stage couldn’t be observed, resulting from the application with the U-shaped FRP composite layers. Having said that, flexural cracks penetrated by means of the best edges on the U-shaped FRP at a failure load of 74 kN, as shown in Figure 14. No debonding of FRP was observed in contrast to the specimen B-01. Nonetheless, final failure was nonetheless accompanied by FRP rupture, as shown in Figure 15.Figure 14. Final failure of specimen B-02.Figure 15. FRP rupture at failure of beam B-02.Polymers 2021, 13,12 ofStrain measurements revealed that strains with the bottom longitudinal bars have been sufficiently exceeded beyond their yield limits. Related to other specimens, concrete crushing was also observed in the top surface. 3.2. Load eflection Curves A comparison of your load eflection curve was essential to Orexin A In Vivo reveal the valuable impact on the strengthening schemes. LVDTs have been mounted in the midspan for this purpose. Figure 16 shows the measured load eflection response of all beams. The load versus deflection response on the handle beams was observed to become tri-linear. The very first aspect represented a linear improve in the load till the very first tension crack. The second portion was also linear till the yielding on the steel bars. However, the stiffness on the second.