Expanded polystyrene (EPS) packaging consumes landfill space when discarded.

Reusing this waste product would relieve landfill pressures and provide geotechnical benefits. Previous studies of waste materials for soil reinforcement highlighted the potential for EPS waste to be used similarly.

EPS beads of varying diameters and concentrations were tested for their influence on friction angles and dry density of sandy soils.

Results showed decreases in the friction angle under heavier loads with larger beads at higher concentrations.

Lower concentrations of smaller beads affected soil strength minimally, allowing them to possibly be used in foundations. The inversely proportional ratio of weight to volume of EPS bulked up soils without increasing mass.

The lower dry density of the composite made it viable for backfill soils. Should waste EPS be employed in fill and foundation soils, the amount of polystyrene destined to landfills would be reduced, alleviating the environmental burden of this type of plastic.

Download technical paper here.