Washed recycled sand derived from construction and demolition wastes as engineering fill materials

The accumulation of construction and demolition (C&D) waste in landfills is a global issue which is exacerbated by the impact of rapid urbanization and increased construction activities in metropolitan and regional areas. The recycled sands studied in this research were derived from processed C&D waste from a washing plant located in Melbourne, Victoria. Two types of washed recycled sands were used as the target materials in this study: coarse recycled sand (CRS) and fine recycled sand (FRS). Extensive geotechnical laboratory tests were performed and the results indicated that both washed sand types exhibited similar geotechnical behavior with conventional virgin materials when used as geotechnical fills. Geoenvironmental tests indicated that the application of washed recycled sand will not have adverse impacts on the surrounding environment. This study highlighted CRS and FRS could both successfully substitute quarry materials required for geotechnical fill and subgrade pavement works.