Asphalt recycling is not a new concept. Cold recycling/rehabilitation of roadways with asphalt binders dates to the early 1900’s. Two events of the 1970’s rekindled interest in asphalt recycling and the development of Cold In-place Recycling (CIR). The two events were the petroleum crisis of the early 1970’s and the development and introduction of large scale cold planing equipment with easily replaceable tungsten carbide milling teeth. Over the years CIR has been proven to deliver cost and emissions savings while delaying or eliminating reflective cracking and other distresses.
However, due to the size of the recycling trains, there are certain geometries and depths that cannot use CIR and in many parts of the country, there are large stockpiles of high quality RAP. This has lead to the development of cold central plant recycling (CCPR) where the cold recycling takes place at a central plant and the materials are hauled to the project location. CCPR is increasing in popularity and many agencies are using CCPR for new construction, shoulder widening and to rehabilitate roads with less material and less disruption to the travelling public.