Dams on the Isère, Drac and Romanche rivers (38)
We were commissioned to carry out this work prior to any reinforcement work on the dykes of the Isère, Drac and Romanche rivers.
The aim is to characterise the internal structure of the works and, in particular, to study resistance to internal erosion.
We took charge of sample collection (core sampling) and laboratory analysis (granulometry, water content, blue stain value, permeability and HET erosion test).
The purpose of the HET test is to characterise the aptitude for internal erosion of a soil subjected to a hydraulic gradient and in which a preferential internal path already exists (root, discontinuity, differential settlement, etc.).
7 sites were drilled to depths of between 2 and 4 metres. For each core hole, an HET analysis was carried out, as well as a GTR analysis and a permeability test.
The facies were described when the cores were opened, with supporting photographic assemblages.