Numerical Study of Flow Characteristics on Landward Levee Slopes Under Overtopping at Different Froude Numbers

Most levees are composed of earthen materials, making their structural stability vulnerable under flood conditions, especially in the case of overtopping. This study aims to analyze the relationship between the channel Froude number and the flow behavior on the landward slope of a levee during overtopping, enabling the prediction of landward slope velocity (LSV) in advance. Accurate estimation of flow velocity on the landward slope is crucial for predicting the occurrence and intensity of erosion during overtopping events, and it serves as a critical criterion for designing protective armoring and assessing levee structural stability. Numerical simulations were conducted under various Froude numbers in the channel to estimate the corresponding LSV. Key variables, including channel discharge, velocity, levee height, and overtopping flow depth, were used to establish quantitative correlations between channel flow characteristics and LSV. The proposed model effectively predicts the LSV for channel Froude numbers approximately between 0.05 and 0.60. The findings allow for a simplified estimation of LSV based on changes in Froude number and overtopping flow depth, providing valuable baseline data for planning levee reinforcement and maintenance strategies.