Asphalt Terminology

The following is a short list of terms used in the asphalt industry.
For a complete list of terms, visit the Asphalt Institute at www.AsphaltInstitute.org.

Aggregate

Hard, inert mineral material, such as gravel, crushed rock, slag or crushed stone, used in pavement applications either by itself or for mixing with asphalt

Asphalt cement

A mixture of crude petroleum used for paving, roofing, industrial and other special purposes.

Asphalt concrete

A mixture of asphalt binder and aggregate thoroughly mixed and compacted into a mass.

Asphalt pavement

Asphalt concrete over supporting courses such as asphalt concrete bases, crushed stone, slag, gravel, Portland Cement Concrete (PCC), brick or block pavement.

Asphalt plant

A manufacturing facility that produces asphalt paving mixtures.

Asphalt Rubber Binder (AR)

Recycled ground tire rubber is added to conventional asphalt cement. Roofing shingles may also be added to the asphalt cement.

Crumb rubber

Asphalt rubber binder with a consistency ranging from coffee grounds to peanut butter.

Hot Mix Asphalt (HMA)

High quality, thoroughly controlled hot mixture of asphalt binder (cement) and well-graded, high-quality aggregate, which can be compacted into a uniform dense mass.

Hot Mix Asphalt (HMA) overlay

One or more courses of HMA over an existing pavement.

Maintenance mix

A mixture of asphalt emulsion and mineral aggregate used in relatively small areas to patch holes, depressions and distressed areas in existing pavements.

Pavement base

The lower or underlying pavement course atop the subbase or subgrade and under the top or wearing course.

Reclaimed Asphalt Pavement (RAP)

Pulverized excavated asphalt that is used as an aggregate in the recycling of asphalt pavements. Factory-rejected roofing shingles can also be added to RAP.

Recycled asphalt mix

A mixture produced after processing existing asphalt pavement materials such as shingles and rubber.

Sheet asphalt

A non-porous material used in reservoir liners and landfill caps.

Source: Asphalt Institute, National Asphalt Pavement Association