Geotechnical characterization of backfill granular materials

In the physical and numerical modeling of buried structures and of pipe covers it is necessary to account for the backfill properties and this suggests identifying proper laboratory procedures for their characterization. In the paper some aspects are considered of the geotechnical tests suitable for the mechanical characterization of two kinds of granular material, namely, natural sand and manufactured lightweight expanded clay aggregate. The experimental investigation is carried out taking into account that limited data are available from the literature on the strength of coarse-grained soils at low stresses.