Author(s): Stefano Pagliara; Michele Palermo; Ottavio Cospolici

Linked Author(s): Michele Palermo, Stefano Pagliara

Keywords: bed morphology; bridge pier; debris accumulation; hydraulics; sloping channel

Abstract: A bridge failure may lead to significant economic damages and loss of lives. Most of failures are caused by excessive erosion at foundations. Therefore, scour at bridge pier represents one of the most challenging topics in hydraulic engineering. Namely, previous studies mainly focused on scour evolution in correspondence with pier without debris accumulation and horizontal mobile beds, under both clear-water and live-bed conditions. However, despite the relevant efforts of the engineering community, there are still many aspects that need to be deepened. For instance, only recently, the effect of debris accumulation on scour morphology has been analyzed. Namely, most of studies dealing with this topic focused on the effect of the shape of debris accumulation and its volume on both the evolution process and the equilibrium configuration. Nonetheless, to the best of authors’ knowledge, all experimental campaigns were conducted with horizontal mobile beds, thus neglecting the effect of channel inclination on the scour phenomenon. Overall, we observed that bed slope influences the resulting morphology, contributing to modify scour geometry and downstream dune, especially in the presence of large debris accumulations. More specifically, the analysis of experimental data allowed us to identify differences between erosion processes at diverse bed slopes. In so doing, this study presents unprecedented and interesting insights on scour mechanism at bridge piers. Furthermore, it represents an advancement of knowledge on the topic, aiming at helping practitioners to better design such strategic infrastructures.

DOI: https://doi.org/10.3929/ethz-b-000675921

Year: 2024