Author(s): Ina Schulte; Harish Selvam; Holger Schuttrumpf

Linked Author(s): Ina Schulte

Keywords: Dikes; Transitions; Roughness; Flow characteristics; Hydraulic loads; Flooding

Abstract: Sea and river dikes are important flood protection measures, not only in Germany but worldwide. The standard green dikes in Germany are mainly covered with a vegetated top layer but do not have a homogeneous surface or bed roughness at all locations. The dikes are characterized by multiple transitions with many changes either in materials or in geometry. In the aftermath of past storm surges and floods, it was observed that the onset of erosion and damage was often initiated at transition points. Thus, these points need special attention in investigation because the dike can only be as strong as its weakest part. Wave overtopping and overflow are the most frequent loadings for dike failure, making investigating the dikes' landward sides very important. This study focuses on the experimental investigation of flow velocities, water depth, and air-water properties to describe the hydraulic load due to overflow at transitions. The transitions increase the hydraulic load by higher velocities as well as additional turbulences and are, therefore, weak spots for erosion on dikes, which must be strengthened.

DOI: https://doi.org/10.64697/978-90-835589-7-4_41WC-P1794-cd

Year: 2025