Breaking up an old concrete pavement and reusing it as aggregate is a cost-effective option for reconstructing deteriorated pavements. Recycling eliminates disposal problems and tipping fees. In urban areas where landfill space is scarce, dumping concrete is difficult and costly. The cost of recycling concrete pavements only includes the cost of crushing. Costs for aggregate hauling and concrete disposal are eliminated.
In some areas, the supply of acceptable natural aggregates is dwindling. Reusing existing material is helpful where quality supplies are scarce. A new concrete mix can contain up to 100% recycled coarse aggregate, and recycled fines can replace 10% to 15% of virgin sand. Fine aggregate also makes good fill for subgrade corrections.
The goal of recycling concrete pavement is to maximize production of coarse aggregate. The coarse aggregates are more valuable and more usable than fines. A contractor has many choices of recycling equipment and processes, each affecting the yield of coarse aggregate. The key steps in recycling portland cement concrete pavements are preparation, breaking, concrete removal, steel separation, and crushing.