## 4 Flexural Behavior
When comparing beams with the same size and BFRP reinforcement configurations, ECC beams exhibited significantly greater ultimate load, ultimate deformation, and energy dissipation compared to conventional concrete beams. Notably, the removal of shear stirrups from the ECC beam resulted in only a marginal decrease in load capacity and deformation when compared to a concrete beam with dense stirrups, underscoring the effectiveness of ECC in enhancing shear capacity. In a parametric study of BFRP-reinforced ECC beams, it was observed that the maximum ultimate curvature was achieved at the balanced reinforcement ratio. An increase in the compressive strength of ECC markedly improved both the ultimate moment capacity and the ultimate curvature of the beam, particularly when failure was governed by ECC crushing in the compression zone. However, the ductility, defined as the ratio of inelastic energy to total energy, remained relatively constant with variations in ECC compressive strength, irrespective of the failure mode. The moment-curvature response of the BFRP-reinforced ECC beam was predicted using a strip model, which showed a strong correlation between experimental and analytical findings. [PERSON] et al. [35] analyzed the flexural behavior of ECC beams reinforced with BFRP bars using a nonlinear finite element model. The simulation outcomes were validated against experimental data published by [PERSON] et al. [34]. Through finite element analysis, the influence of various parameters on the mechanical behavior of BFRP-reinforced ECC beams was investigated. These parameters included compressive strength (CS) values of 30, 45, 60, and 75 MPa, ultimate tensile strain (TA) levels of 0.5, 1.5, 2.5, 3.5, and 4.5%, tensile strength of ECC (TE) at 2, 4, 6, and 8 Mpa, and longitudinal reinforcement ratios (LR) of 0.2, 0.4, 0.6, 0.8, and 1%. The findings, illustrated in Figure 11, indicate that the ultimate strength of the beams increased with all parameters, except for the tensile strain of ECC when it exceeded 1.5%. Additionally, the ultimate deflection was observed to rise with increasing compressive strength and tensile strain of ECC, while the ultimate tensile stress exhibited minimal influence on the ultimate deflection of BFRP-reinforced ECC beams. Furthermore, variations in the longitudinal reinforcement ratio were found to alter the failure mode of the ECC beams. Notably, for over-reinforced beams, an increase in the longitudinal reinforcement ratio resulted in a decrease in ultimate deflection. The simulation results showed good agreement with the experimental results. [PERSON] et al. [36] examined the influence of the stress-strain characteristics of FRP bars on the load-deformation behavior of FRP-reinforced ECC members subjected to reversed cyclic loading conditions. An analytical model was formulated to represent the load-deflection envelope, which was derived from the moment-curvature relationship and the sectional stiffness of the flexural members as a function of the applied load. The findings indicated that the load-deformation response of FRP-reinforced ECC is predominantly governed by flexural deformation, even at substantial drift levels, with crack initiation appearing to be largely independent of the interfacial bond properties. The inelastic deformation of ECC under compressive loads results in a reduction in flexural stiffness and ultimately leads to a gradual failure mode. However, it concurrently induces compressive strain and reduces the tensile strength of the FRP reinforcement. The analytical model demonstrated reasonable agreement with the experimental results; nevertheless, it did not account for rotational sliding, which can significantly affect the flexural stiffness and strength in certain scenarios. [PERSON] et al. [37] proposed a modified model that aimed at predicting the maximum crack width in ECC beams reinforced with CFRP bars, specifically within the service limit state. The calculation methodology for this model was based on the principles of the Chinese standard GB50608 [45].