Characterising the collapsible response of an in-situ compacted silt

The paper presents selected experimental results of the microstructure, the hydro-mechanical properties and the volume change response along wetting and drying paths of a compacted silt. The material was recovered from a fully-instrumented embankment, which was specifically built to study the earth-structure response in areas liable to flooding. Data presented allowed studying the microstructural changes and the variation of the hydraulic properties (water retention and water permeability) along the different stages of the in situ case. Controlled-suction paths following equivalent stress paths to those undergone by the material under real conditions are presented. Comparisons between field data during flooding and equivalent experimental results are discussed.