A Practical Method to Determine Reclaimed Asphalt Pavement (RAP) Binder Availability

Recycled binder availability (RBA) is the proportion of total recycled binder in a reclaimed asphalt pavement (RAP) source that is available to blend with virgin asphalt. Partial RBA is a consequence of agglomerations of adhered RAP particles. RAP binder locked inside of an agglomeration is ‘unavailable’ whereas the binder within the peripheral mastic coating of an agglomeration is ‘available.'

The TRB IDEA (Innovations Deserving Exploratory Analysis) Program's NCHRP IDEA Final Report for Project 236: A Practical Method to Determine Reclaimed Asphalt Pavement (RAP) Binder Availability details the development of a method to quantify the extent of agglomeration in a given RAP source, and in turn, the RBA using comparative sieve analysis of RAP and recovered RAP aggregate.