Effective reinforcement ratio of <scp>RC</scp> beams: Validation of modelling assumptions with high‐resolution strain data

Concrete tensile stresses influence the cracking behaviour and stiffness of reinforced concrete (RC) members. Most design codes account for this tension stiffening effect using an effective reinforcement ratio. Although ratio has a significant on RC structures, its quantification is controversial in many cases, typically relies empirical geometry-based expressions. One main reason knowledge gap that area can only be verified indirectly, example, through crack widths spacings suitable mechanical model. This indirect validation subject to considerable uncertainty as it depends parameters scatter (e.g., bond strength), further assumptions relating internal applied loads are required. article outlines how refined measurements reinforcing steel strains deformations compression zone, combining distributed fibre optic sensing (DFOS) digital image correlation (DIC), used order obtain more reliable affecting hence, Selected models validated against experimental data beam tested under four-point bending, underlining potential DFOS DIC valuable tools better understanding structures enhancement models.