Fluid-structure induced scour in the FlexiArch bridge system

In contrast, scour at the mobile bridge initially followed the same pattern but diverged beyond a critical scour depth, increasing linearly with settlement. This deeper scour—exceeding empirical model predictions for the immobile case—is termed fluid-structure interaction-induced scour, driven by the interaction between settlement and flow.<br><br>These findings suggest that current scour models, which assume bridge immobility, may underestimate risk when settlement occurs.

The linear increase in scour depth with settlement could accelerate scour progression and bridge failure, triggering a scour-settlement cycle.<br><br>Overall, this study highlights the need for improved scour estimation methods that integrate hydraulic, geotechnical, and structural interactions to enhance bridge safety assessments. Further computational research could help identify conditions where fluid-structure interaction-induced scour becomes significant and where immobile assumptions may underestimate scour damage.<br><br><i>Thesis is embargoed until 31 July 2029.</i><br>