O steer clear of the de-bonding from the FRP in the tensions side of RC beams. Therefore, within this study, the RC beam (B-02) was strengthened having a u-shaped pattern on the surface beneath its neutral axis, as shown in Figure two. In the u-shaped pattern, the hybrid FRP composite was applied in the sides and bottom. Table 1 summarizes the strengthening scheme adopted in this study.Figure 1. Strengthening detail of beam B-01 (units: mm).Figure two. Strengthening detail of beam B-02 (units: mm). Table 1. Test matrix and strengthening scheme. Beam ID B-CON B-01 B-02 Hybrid FRP Layers N/A 4 four Strengthening Pattern N/A Bottom face only U-shaped patternPolymers 2021, 13,5 of2.1. Specimen Specifics RC beams had a cross-section of 150 mm 300 mm with a support-to-support length of 2500 mm. The total length of each and every beam was 2800 mm. The prime and bottom longitudinal bars consisted of two 12 mm-diameter deformed bars. Shear reinforcement consisted of six mm diameter round bars. Inside the shear span, the spacing of stirrups was 100 mm, which was doubled just outside the shear spans. A concrete cover of 20 mm was supplied on all sides. Particulars in the RC beams are shown in Figure three.Figure 3. Specimen details (units: mm).two.two. Material Properties Deformed and plain steel bars have been utilized for longitudinal and transverse reinforcement, respectively. Their Benzodioxole fentanyl-d5 In Vivo mechanical properties had been discovered following the protocols of ASTM A615/A615M – 20 [31]. A total number of 5 steel bars were tested for every single form of steel bar. Table 2 presents the “average mechanical properties of steel bars” in terms of diameter, DY268 FXR elastic modulus, yield pressure, yield strain, fracture tension, and strain. All beams were constructed employing a single batch of concrete. Normal cylinders were cast as per the recommendations of ASTM C39/C39M – 21 [32]. For this goal, 3 cylinders of normal size, i.e., 150 mm 300 mm (diameter height), had been cast and tested beneath axial compression. Table 3 shows the “average concrete qualities.” In this study, woven basalt fabric was offered by Kamenny Vek, Russia, and locally accessible woven jute fabric was applied. The epoxy resin was obtained from Smart and Bright Co., Ltd., Thailand. The epoxy resin was made of two components, i.e., resin and hardener. The mixing ratio of resin was regarded as as 1:two (hardener:resin). Further, the properties of FRP composites had been determined following the procedures of ASTM D7565/D7565M – ten(2017) [33]. A total variety of ten tensile strips were tested to get the typical mechanical properties of basalt and jute FRP composites. The properties of FRP composites are provided in Table four.Polymers 2021, 13,6 ofTable 2. Mechanical properties of steel reinforcement. Bar Variety DB12 RB6 Elastic Modulus (GPa) 200 220 Yield Strain (MPa) 520 330 Yield Strain ( ) 2.7 1.57 Fracture Anxiety (MPa) 660 480 Fracture Strain ( ) 17.8Table three. Concrete properties. Material Concrete Elastic Modulus (MPa) 2.75 104 Tensile Strength (MPa) 1.98 Compressive Strength (MPa) 20.Table four. Properties of composite polymers. FRP Sort Basalt Jute Epoxy Peak Anxiety (MPa) 81 16.3 75 Fracture Strain ( ) 2.4 1.26 N/A Bond Strength (MPa) N/A N/A 2.2.3. Instrumentation and Load Setup Every single beam was subjected to the four-point bending test with a load increment of five kN until failure. Points of load had been 250 mm on every side with the centerline from the beam, as shown in Figure four. Strain gages have been installed around the bottom longitudinal bars at three unique places, as shown in Figure 5. Four.