Degradation assessment of recycled aggregates from Construction and Demolition Waste through wet-dry cycles

Abstract

In recent years, several studies and applications of recycled aggregates coming from Construc-tion and Demolition Waste (CDW) have been carried out, but the knowledge related to the long-term behaviour of these alternative materials is still fairly limited. The breakage of CDW particles is commonly pointed out as an issue for the use of these recycled materials. This paper studies the change of the particle size distribution of a recycled aggregate coming from CDW due to degradation agents simulated trough 10 wet-dry cycles under controlled conditions. The effects on particle density, water absorption, shape index, flakiness index, sand equivalent value, Los Angeles abrasion, aggregate crushing value, water-soluble sulphate content are assessed. Wet-Dry cycles have degraded the mixed recycled aggregate, increasing the amount of particles with small di-mensions, however the changes in its mechanical and physical behaviour are not very significant. LA abrasion loss of this recycled aggregate is high making its use on unbound pavement layers difficult.