ArticlePublisher preview available

Real time instability of flow close to a scour affected abutment

June 2022
Environmental Fluid Mechanics 22(25):1-16

DOI:10.1007/s10652-022-09842-9

Authors:

Christophe Chevalier

Gustave Eiffel University

Frédérique Larrarte

Gustave Eiffel University

For centuries, the interaction between the transport and hydrographic networks represents a significant issue in a country such as France. For example, the French railway network includes 1700 river-crossing structures and an important length of embankments either forming river banks or adjacent to watercourses exposed to scouring processes. Recently, various cases highlight the importance and vulnerability of civil transport works in relation to their environmental hazards, e.g. floods, and therefore the need to develop integrated observation tools and warning systems in the aim both of optimizing the management system and of increasing the knowledge on real scour processes. This paper relies to a French research project named SSHEAR which objective is to improve understanding of the scouring process through the use of innovative observation tools and physical and numerical hydraulic modelling. This part of the project aims at improving continuous monitoring in order to follow the evolution of the scour processes of a given bridge or abutment. After a presentation of the experimental site, the instrumentation is described as well as its in situ implementation. The data analysis process is given and results are commented before the presentation of some perspectives part.

Bathymetric survey made in 2018. Red circle: place of the monitoring set-up (Larrarte et al. [31])

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Monitoring set-up installed on the abutment site

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Definition of the various heights

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Lateral sketch of the profiler

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Amplitude of the backscattered signal and bottom location, between June 21st and July 4th of 2019, the black line represent the free surface position

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Vol.:(0123456789)

Environmental Fluid Mechanics (2022) 22:495–510

https://doi.org/10.1007/s10652-022-09842-9

1 3

ORIGINAL ARTICLE

Real time instability ofﬂow close toascour aﬀected

abutment

ChristopheChevalier1 · FrédériqueLarrarte1,2

Received: 15 November 2021 / Accepted: 7 February 2022 / Published online: 16 February 2022

Abstract

For centuries, the interaction between the transport and hydrographic networks represents

a signiﬁcant issue in a country such as France. For example, the French railway network

includes 1700 river-crossing structures and an important length of embankments either

forming river banks or adjacent to watercourses exposed to scouring processes. Recently,

various cases highlight the importance and vulnerability of civil transport works in rela-

tion to their environmental hazards, e.g. ﬂoods, and therefore the need to develop inte-

grated observation tools and warning systems in the aim both of optimizing the manage-

ment system and of increasing the knowledge on real scour processes. This paper relies to

a French research project named SSHEAR which objective is to improve understanding

of the scouring process through the use of innovative observation tools and physical and

numerical hydraulic modelling. This part of the project aims at improving continuous mon-

itoring in order to follow the evolution of the scour processes of a given bridge or abut-

ment. After a presentation of the experimental site, the instrumentation is described as well

as its insitu implementation. The data analysis process is given and results are commented

before the presentation of some perspectives part.

Highlights

• Field study,

• Scour,

• Experience feed back.

Keywords Monitoring· Data analysis· Hydraulics· Instrumentation

* Frédérique Larrarte

frederique.larrarte@univ-eiﬀel.fr

Christophe Chevalier

christophe.chevalier@univ-eiﬀel.fr

1 GERS-SRO, Univ Gustave Eiﬀel, 77454Marne-la-Vallée, France

2 Laboratoire d’Hydraulique St Venant, 6 quai Watier, 78401Chatou, France

Content courtesy of Springer Nature, terms of use apply. Rights reserved.

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