PSI - Issue 84

Giulia Rossini et al. / Procedia Structural Integrity 84 (2026) 1183–1190

1190

the test sections, generally showed a satisfactory level of agreement, while also highlighting the influence of bridge specific uncertainties. For bridges not exhibiting significant signs of degradation, the prestress losses inferred from the experimental results were found to be broadly consistent with typical long-term losses commonly assumed at the design stage. For bridges showing pronounced shear cracking patterns, higher estimated prestress losses were observed; however, these results should be interpreted with caution due to uncertainties related to prestressing details, load distribution and boundary conditions. Overall, the findings suggest that the saw-cut stress-release technique represents a useful and minimally invasive tool for supporting the assessment of residual prestress in existing bridges, particularly when integrated with other diagnostic investigations. 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