September 4-7, 2017, Delft, the Netherlands - 25th Meeting of the European Working Group on Internal Erosion.
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Large triaxial device for suffusion erodibility and mechanical
behavior characterization of coarse soils
D. Marot, F. Bendahmane, R. Andrianatrehina & R. Gelet
University of Nantes, Institute GeM, UMR CNRS, 58 rue Michel Ange, Saint-Nazaire, France
Keywords: dam and dike safety, suffusion, erodimeter, water seepage energy, mechanical strength.. Suffusion, one of the main internal erosion processes, selectively erodes the fine particles which move through the voids formed by the coarser particles. In the literature, the mechanical consequences of suffusion on soil were investigated by several researchers. However, no general conclusion can be drawn because the already published results appear to be opposite. The objective of this study is to investigate these consequences. A large triaxial erodimeter was developed in order to perform suffusion tests and triaxial tests on coarse soils which are often encountered in French dikes. For the suffusion characterisation, the proposed interpretative method is based on the energy expended by the seepage flow and the cumulative loss of dry mass. The results of triaxial tests on non-eroded and eroded specimens show the significant effect of an achieved suffusion process on the mechanical strength of soils.
