Canal bed configurations caused by vibrations of suspended pipelines crossing the watercourse

ABSTRACT This study presents one of the first integrated numerical and experimental studies focusing on the effect of pipeline vibrations on canal bed scour for suspended pipelines through extensive analysis, encompassing 300 numerical simulations and 25 complementary laboratory experiments. Numerical outcomes were validated against experimental measurements, demonstrating strong conformity with discrepancies consistently within ±10%, therefore emphasizing the reliability of our numerical modelling approach. The study findings explicitly reveal that scour depth and morphology were substantially affected by pipeline height, vibration amplitude, pipeline diameter, and flow conditions (represented by the Froude number). Specifically, temporal evolution significantly influences scour development, with vibration amplitude playing a particularly decisive role. Increasing the vibration amplitude from a baseline value of (A/D = 0.2) to double, triple, and quadruple this value resulted in respective increases in scour depth of approximately 12, 47, and 71%. A 27% reduction in scour depth when the pipeline diameter is reduced by 40%. The critical influence of Froude number and vibration frequency. Consequently, these quantitative insights underscore the critical necessity of accurately considering pipeline-induced vibrations in the hydraulic design and protection strategies of river-crossing pipelines to effectively mitigate associated scour risks.