Reuse of waste material from decorative quartz solid surfacing in the manufacture of hot bituminous mixes

Due to the increasingly strict environmental restrictions on quarry exploitation, there are severe limitations on the use of natural aggregate for road construction. The accumulation of waste in landfills is also a pressing problem for many businesses, both from an environmental and economic perspective. This article presents the results of a research project, which studied the reuse of engineered quartz (Silestone®) waste material as aggregate in hot bituminous mixes. After a preliminary study of the material, four bituminous mixes were manufactured, which differed in their percentage of Silestone® waste aggregate. These mixes were applied to the surface course. Based on the highly satisfactory laboratory results obtained, the mixes were then on an actual road in Almanzora (Spain). The four mixes made from this waste material were found to meet PG-3 specifications, and consequently, were deemed suitable for road surfacing. Nevertheless, since this was the first time that this type of material has been used for this purpose, in the future it will be necessary to test the medium- and long-term mechanical behavior of the road surface.