Influence of Sample Holding Time on the Fluvial Erosion of Remolded Cohesive Soils

Abstract

Despite extensive research on bridge scour and channel erosion, predicting the occurrence and rate of cohesive soil erosion remains problematic. The lack of standard procedures for sample preparation and testing has resulted in wide variations in testing conditions, devices, and soil properties across erosion studies, ultimately preventing the synthesis of cohesive erosion studies and progress in understanding the fundamental processes of cohesive soil erosion. Therefore, the objective of this study was to evaluate the effects of sample holding time on the fluvial erosion of remolded cohesive soils to inform the development of standard testing procedures. Three different soils (fat clay, lean clay, and silty sand) were tested in a flume following multiple sample holding times. Results show that erosion rate can decrease 85–95% within 72 h of soil wetting, depending on clay mineralogy. These results highlight the importance of maintaining a consistent soil preparation protocol in cohesive soil erosion experiments and reporting soil sample holding durations when conducting cohesive erosion research using remolded samples.