## 3 Results and Discussion
### Strain on the Concrete and Stirrups  
Since all test beams adopted a strong shear-weak flexural design approach, none of the beams exhibited shear failure at their ultimate states. Therefore, it is not viable to adequately evaluate the enhancement of external prestressed CFRP tendons on the shear-bearing capacity of reinforced beams solely through shear load analysis. Upon analyzing Figure 8a, it becomes evident that when subjected to a moment of 48 kN\(\cdot\)m, the stirrup strain of the SCB beam shows a significant and rapid increase. This phenomenon provides an indication that deformation has initiated within the shear span region of the concrete beam. While observing each reinforced beam, it becomes apparent that the flexural moment corresponding to the significant rise in stirrup strain has also increased. Suggesting that the externally prestressed CFRP tendons have assumed a portion of the shear force initially carried by the concrete and stirrups. The graph in Figure 8a demonstrates that the slope of the curve increases as the prestress level rises. This indicates that the application of external prestressed CFRP tendon reinforcement has a positive effect on enhancing the shear resistance capacity of the concrete beam. Furthermore, the enhancement in shear capacity is positively correlated with the prestress level of the CFRP tendon. Upon contrasting the curves of specimens S-SL-0-0 and S-C-0-0, it is evident that when CFRP tendons are arranged in a flexural pattern, both the slope and the initial point of the curve surpass those in a straight-linear configuration. This observation implies that the flexural arrangement of the CFRP tendon, in contrast to the straight-line arrangement, provides enhanced contributions to the beam's capacity for shear resistance. Figure 8b showcases the comparison of stirrup strain in the shear span region of continuous beams and simply supported beams subjected to identical conditions. In the context of continuous beams, it is evident that the CCB beam experiences a significant escalation in stirrup strain when exposed to a flexural moment of 40 kN\(\cdot\)m, whereas the C-C-30-0 beam demonstrates a similar quick increase in stirrup strain starting at the moment of 74.3, which equates to a notable 85.8% augmentation in flexural moment. It becomes apparent that the slope of S-C-30-0's curve exceeds that of C-C-30-0's curve. This observation implies that the use of external prestressed CFRP tendons results in a reduced rate of stirrup strain growth in the simply supported beam compared to the continuous beam. Therefore, the influence  
Figure 7: Comparison of crack widths: (**a**) Curve of maximum crack width for simply supported beams; (**b**) comparison of crack widths between continuous beams and simply supported beams. of CFRP tendon reinforcement on shear capacity is more significant in simply supported beams compared to continuous beams. As depicted in Figure 9, the strain of the concrete at the mid-span cross-section for both simply supported and continuous beams essentially aligns with the plane section assumption. Consequently, this assumption is utilized for the computational analyses in the following calculations on flexural capacity. Before the test beam cracks, the strain observed in the CFRP tendon is small, indicating that its contribution is insignificant during Phase I. However, once the external moment exceeds the cracking moment, there is a discernible augmentation in strain within the externally prestressed CFRP tendon, as it commences to assume the role of flexural resistance with the tensioned steel reinforcement. Upon exceeding the yield moment, the strain increment within the CFRP tendon becomes even more noticeable. The evaluation of an externally prestressed concrete beam as a solitary unit is impeded by the strain disparity between the CFRP tendon and the concrete.