Author(s): M. Maknoon; Tew-Fik Mahdi; Mohamed Chekired

Linked Author(s): Tew-Fik Mahdi

Keywords: No Keywords

Abstract: Suffusion, the wash out of fine particles throughout voids between coarser particles in embankment dam is a mode of internal erosion phenomenon. To study the effect of hydraulic head on the internal erosion among two different type of sediment, a series of experiments has been conducted in hydrodynamic laboratory of ecole polytechnique de Montreal (with cooperation of Hydro Quebec). Considering the specifications of materials, the granulometry, compaction and the changes in hydraulic head, the experiments were done for gravel/sand and sand/moraine level. The results reveal the relation between hydraulic head changes and the material proprieties. The increase of hydraulic head over the moraine core, does not show visible erosion on the interface of sand and moraine, whereas increasing the hydraulic head over the sand layer, cause rapid erosion in the head of the trapezoid earth-dam. Our experiments show that rate of erosion is in relation with the porosity of gravel and the length of the sand bed does not have much influence on the erosion rate. It's also noticeable that contrary to most experimental works that are done in small size, ignoring the geometric similarity; the presented experiments are done using similarity concepts.

DOI:

Year: 2009