Evaluation of Biopolymer Treatment Effects on Overtopping Erosion and Breach Development in Earthen Embankments Using Numerical Models

Abstract

This study evaluated the ability of existing overtopping breach models to represent the effects of biopolymer treatment on earthen embankment erosion and breach development. Two full-scale experimental datasets were used: the Kang et al. (2021) overtopping test and the ERDC Breland et al. experiment. The behavior of treated and untreated embankments was simulated using WinDAM C and DLBreach. The study compared predicted breach initiation, headcut migration, breach widening, and hydraulic control behavior with observed responses. Models were found to be generally more successful at reproducing the final breach width than at reproducing the full erosion history. Biopolymer treatment consistently improved erosion resistance by delaying initiation and slowing breach progression, but this effect was only partially represented in the models through calibrated parameter adjustments. A Dakota sensitivity analysis showed that the dominant controlling parameter varied by model: AC governing the WinDAM C energy model, kd governing the WinDAM C stress model, and Manning’s n most strongly influencing DLBreach. Pearson and Spearman results generally agreed and showed both linear and nonlinear parameter relationships. Overall, the results indicate that current breach models can approximate some end-state behavior of biopolymer-treated embankments, but they remain limited in their ability to represent the full sequence of overtopping failure, especially headcut migration.