Swelling/collapsible behaviour of a dynamically compacted silty sand

The paper reports on an laboratory study carried out on a Proctor compacted silty sand typical of earth construction materials. Tests have been performed under suction controlled conditions, using a stress-path triaxial cell and an oedometer device recently developed at the Dipartimento di Ingegneria Geotecnica of Naples (Italy). The observed behaviour effectively framed within the elasto-plastic modelling criteria for partially saturated soils and permits the identification of the initial yield locus induced by the sample preparation process. The experimental data pertaining to variable-suction tests match this reference framework and stress the reversible soil response upon wetting and unreversible behaviour on drying. Overall, the reported data give interesting ideas for modelling the mechanical response of granular compacted soils.