3D Scour Due to Low-Inclined Circular Jets in Cohesive Soils: A Preliminary Analysis

Jet-induced scour is a common phenomenon occurring downstream of many hydraulic structures (e. g., dams, culverts, spillways, and bridges). While scour can lead to structural failure, it can also be regarded as an essential means to enhance river and marine habitats. This dual nature of the mentioned phenomenon necessitates a deep understanding of its underlying physics. Despite the practical significance of this topic, studies on scour due to inclined jets in cohesive soils are relatively scarce. Nonetheless, a comprehensive analysis of three-dimensional scour induced by plunging jets has been recently conducted, considering both developed and developing jets under various hydraulic conditions and jet angles ranging from 45° to 90°. In this paper, we provide a preliminary analysis of the characteristic features of the scour morphology at jet inclination of 30°. To this end, we first confirm that the equations derived elsewhere for predicting scour features at higher jet inclinations remain generally applicable to the case of jet angle equal to 30°. Then, we describe and discuss the kinetics of the scour process, highlighting that at lower jet inclinations a distinct form of mass erosion may occur.