## 3 Results and Discussion
### Behavior of Reinforced Concrete Beams  
Figure 12 presents the Load deflection curves for all the RC beams tested. The beam containing 10% powder glass and 0% PA exhibited the best performance in terms of both ductility and load capacity. The maximum load capacity for this beam was slightly higher, around 20%, than the control beam (0%G, 0%PA). As for the other beams, the load capacity increased compared to the control beam, with the increase ranging from 1.6% to 2.9%. However, a slight decrease of 1.2% was observed in Beam 3 (10%G, 0.5%PA). The data for load deflection are summarized in Table 4. The highest yield and failure deflection were observed in Beam 3, indicating that the incorporation of 0.5% PA fibers improved the ductility of the concrete. This improvement is mainly attributed to the application of  
Figure 9: Correlation between UPV and compressive strength at different curing ages. chemicals to PA fibers, which improves the connection between the fibers and the polymer matrix, resulting in increased roughness on the fiber surface and stronger bonding. This leads to a reduction in cracks and shrinkage during drying. Moreover, the addition of dry, pre-treated PA fibers into the mix results in lower shrinkage during drying. Figure 11: Flexural strength for prisms with powder glass and PA fibers (3 prisms/mix). Figure 10: Split tensile strength for cylinders with powder glass and PA fibers (3 cylinders/mix). The crack pattern for all the beams is shown in Figure 13. The failure of all the beams was due to flexure, with varying numbers of cracks. Beam 3 exhibited the most cracks due to its greater ductility compared to the other beams. PA fibers are not brittle like synthetic fibers and are more flexible. Thus, they can absorb more energy before failure. Furthermore, the addition of PA fibers improves the overall strength and stiffness of the beam, delaying the onset of cracking, which, in turn, increases the ductility of the beam. PA fibers have good compatibility with the matrix, improving the interfacial bonding between the fibers and the matrix, leading to more homogeneous stress distribution, reducing stress concentrations, and increasing ductility. The strain distribution of the beams was analyzed by adding demec points at different depths, as shown in Figure 14. The strain distribution along the depth of the beam at different load increments is shown in Figure 15 for Beam 1 (0%G, 0%PA), Beam 2 (10%G, 0%PA), Beam 3 (10%G, 0.5%PA), Beam 4 (10%G, 1%PA), and Beam 5 (10%G, 1.5%PA). As demonstrated in the data, as the applied load increases, the strain on the beam also increases. Beam 2 exhibited the lowest strain values among the other beams tested, which is directly related to its higher ultimate load, as shown in Table 4 (47.61 kN). This suggests that Beam 2 has a higher resistance to deformation and is able to withstand greater loads \begin{table}
\begin{tabular}{c c c c c} \hline \hline  & **Maximum Load (P\({}_{\text{max}}\))** & **Deflection at Yield (Y\({}_{\text{y}}\))** & **Deflection at Failure (Y\({}_{\text{u}}\))** & **Ductility Index** \\  & **(kN)** & **(mm)** & **(mm)** & **(Y\({}_{\text{u}}\)/Y\({}_{\text{y}}\))** \\ \hline B1:0\%G, 0\%PA & 39.8 & 1.8 & 5.4 & 3.0 \\ \hline B2: 10\%G, 0\%PA & 47.6 & 1.7 & 11.6 & 6.8 \\ \hline B3: 10\%G, 0.5\%PA & 39.4 & 2.5 & 17.6 & 7.0 \\ \hline B4:10\%G, 1\%PA & 40.5 & 2.3 & 12.8 & 5.7 \\ \hline B5:10\%G, 1.5\%PA & 40.9 & 3.0 & 11.2 & 3.7 \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Load deflection data for all RC beams. Figure 12: Load deflection for RC beams with powder glass and PA fibers. before failure. The higher ultimate load of Beam 2 can be attributed to its superior strength and stiffness, which could be the result of using powder glass. The inclusion of powder glass in the concrete can help to reduce the occurrence of cracking by providing additional support for the concrete matrix. These findings are consistent with a previous study by [PERSON] et al. [48].