The Hole Erosion Test: A Comparison of Interpretation Methods

Abstract

The hole erosion test (HET) is widely performed for determining soil erosion characteristics; viz. critical shear stress, erosion rate coefficient, and erosion rate index. Refinements to measurement/estimation of water head drop in the hole through the specimen, which is essential in accurate interpretation of HET, were proposed. Particular attention was devoted to head losses in the entrance/exit of flow to/from the hole in the specimen, and any changes in the hole's entrance geometry. Soil erodibility parameters of 13 core soils obtained in HET through previously available methods, and the new proposed technique were described and compared. Results suggested that, although differences are observed between erosion rate coefficient and critical shear stress from different methods, the erosion rate indices were close, in so far as the interpretation methods manifest an identical classification for soil erosion propensity.