A Review of the Experimental Approaches for Modeling the Overtopping Breach Process in Embankment Dams

Abstract

Experimental tests are essential to gain a better understanding of the dam breaching process and establish efficient precaution plans. This paper reviews and evaluates the previous experimental studies that considered the breaching of embankment dams due to overtopping. The paper addresses the overtopping breach parameters, scaling and similitude basics, progress in measuring devices and their accuracies, aims of previous dam breach experiments, and factors affecting the dam breaching process. It also highlights the most common sources of uncertainties that should be accounted for while studying this complex phenomenon experimentally. The research objectives are to clarify the extent of knowledge in this field, discuss the methods used, highlight the best practices, and point out the gaps that should be addressed in future studies. This provides a solid starting point for researchers who want to tackle the problem of embankment dam breaching using experimental modeling. The conclusions highlight that image analysis is the most common measurement practice in experimental studies. Moreover, to ensure reliable modeling, the Froude number scaling criterion should be used coupled with decreasing the sediment size by the same geometric scaling factor. It is also recommended to fix the construction procedures for all experiments, add seepage control measures to the dam, select a model width that eliminates the sidewall effects, and carve the breach initiation channel at the crest’s center. The repeatability of experiments should also be tested to add confidence to the results. Finally, the paper clarifies the factors that affect the breaching process and presents ideas for future studies.