Recycled Industrial and Construction Waste for Mutual Beneficial Use

Instead of going to landfills, certain waste materials from industry and building construction can be recycled in transportation infrastructure projects, such as roadway paving. The beneficial use of waste materials in the construction of transportation infrastructure results in environmental benefits, as well as economic savings over the pavement life cycle. This study focused on the use of waste--i.e. reclaimed asphalt pavement (RAP), recycled asphalt shingles (RAS), ground tire rubber (GTR), recycled concrete aggregate (RCA), construction and demolition waste (CDW), and mine spoil as raw materials for building transportation infrastructure in Arizona. Technical feasibility, availability, and economics were considered in making recommendations regarding expanding the use of the most-promising materials. Recommendations included targeting slight increases in the RAP replacement level (especially in non-surface hot-mix layers and in unbound base and subbase layers), increasing use of GTR through terminal blending, and increasing use of RCA as base and subbase. Other opportunities identified for further investigation include significant increases in RAP replacement level in hot mix asphalt, use of RCA to replace virgin aggregate in new concrete, and facilitation of the use of CDW in some markets. Further research is encouraged on the use of construction and other waste materials to improve the performance of these materials to reduce risk and improve cost effectiveness.