Start Date
2018 8:00 AM
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.
Recommended Citation
Pagliara, Stefano (2018). A Preliminary Study of Field Scour Morphology Downstream of Block Ramps Located at River Bends. Daniel Bung, Blake Tullis, 7th IAHR International Symposium on Hydraulic Structures, Aachen, Germany, 15-18 May. doi: 10.15142/T39352 (978-0-692-13277-7).
Abstract
Most of the studies present in the literature deal with block ramps located in straight channels. This is an evident limitation not allowing for a generalization of laboratory model findings. Generally, these structure typologies are located in natural rivers, that are characterized by both quasi-straight branches and bends. In particular, the location of the structure in river bends contributes to deeply modify both the upstream in-flow conditions and the downstream erosive mechanism. Only recently, the scour process downstream of block ramps was analyzed in curved channels and useful relationships were proposed to compute the maximum scour depth. Furthermore, the mentioned analysis was supported by field data validation, resulting in the understanding of the effects of river curvature on downstream scour process in the presence of a protected stilling basin. Despite of the recent study on the topic, there is still a lack of knowledge regarding the equilibrium morphology configuration and the effect of hydraulic parameters on the erosive process. Based on field measurements collected at the Porębianka river (Poland) after flood events, this paper aims to deep the downstream scour hole characteristics and the erosive dynamics. In particular, both the effects of in-flow conditions and river curvature are analysed in terms of resulting equilibrium morphologies, highlighting both similarities and differences with the corresponding configurations occurring in quasi-straight river branches.
A Preliminary Study of Field Scour Morphology Downstream of Block Ramps Located at River Bends
Most of the studies present in the literature deal with block ramps located in straight channels. This is an evident limitation not allowing for a generalization of laboratory model findings. Generally, these structure typologies are located in natural rivers, that are characterized by both quasi-straight branches and bends. In particular, the location of the structure in river bends contributes to deeply modify both the upstream in-flow conditions and the downstream erosive mechanism. Only recently, the scour process downstream of block ramps was analyzed in curved channels and useful relationships were proposed to compute the maximum scour depth. Furthermore, the mentioned analysis was supported by field data validation, resulting in the understanding of the effects of river curvature on downstream scour process in the presence of a protected stilling basin. Despite of the recent study on the topic, there is still a lack of knowledge regarding the equilibrium morphology configuration and the effect of hydraulic parameters on the erosive process. Based on field measurements collected at the Porębianka river (Poland) after flood events, this paper aims to deep the downstream scour hole characteristics and the erosive dynamics. In particular, both the effects of in-flow conditions and river curvature are analysed in terms of resulting equilibrium morphologies, highlighting both similarities and differences with the corresponding configurations occurring in quasi-straight river branches.