Abstract
Flood hazards (flow depth and velocity) must be accurately assessed in high-risk areas during extreme flood events. However, the prediction of the very high flows is not an easy task due to the lack of field data and to the strong link between flow resistance and the land occupation of the floodplain. Confinement and inhomogeneity in lateral and longitudinal directions of hydraulic roughness strongly vary with return period T . The physical processes are complex, some still largely unexplored, and the assumptions linked to numerical modelling cannot be validated without field data. The FlowRes project (2015-2018), funded by the French National Research Agency (ANR), aims at improving the flood hazard assessment in floodplains in: 1) investigating in laboratory the hydrodynamic structure associated with extreme flood flows for various land occupations and flow discharge magnitudes; 2) assessing if the existing numerical modelling practices used for T ~ 100 years are still valid for extreme events with T > 1000 years, relying on the experimental data and on one field case. This paper reports some results obtained during the first year of the project.
Highlights
The project focuses on the flow resistance caused by three types of hydraulic roughness elements commonly encountered on floodplains: meadows, trees and houses
The roughness elements shape must allow a comparative study of urban-like canopies formed by cubic roughness elements and plant-like canopies formed by elongated roughness elements
The results show that, in the upstream reach (x
Summary
Both the specific physical processes related to the very high flows and their numerical modeling are handled. Events with a return period T~100, 1000 and 10000-year are simulated with both classical and improved methods, and the discrepancies will be calculated This project will permit to quantify uncertainties on water levels and velocities computed for extreme events. The present paper focuses on the work carried out during the first year of the project (2015), mostly measurements in laboratory flumes and preliminary numerical results
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
