Construction and demolition (C&D) waste is a central component of the solid waste stream, amounting to roughly 25 percent of total solid waste nationally. The largest part of C&D material is concrete, which encompasses around 40 to 50 percent of C&D generated material. With pressure on landfills continuing to mount, the diversion of C&D materials in general, and concrete, in particular, remains an import area of interest to policy makers.
There is a range of environmental and economic benefits in recycling concrete rather than dumping it or burying it in a landfill. These advantages include:
Aggregate base course (road base) The largest application of recycled concrete aggregate (RCA) is for the aggregate base course in road construction. This term refers to the center layer of the road bed. A cross-section of pavement would show dirt, or subgrade, as the lowest of three levels, layered on top by aggregate base course, and finally capped on top by pavement, either concrete or asphalt.