Originally a naturally occurring product in use for centuries the early 1900's brought today's refined petroleum product. This term is often applied to almost any asphalt product from H.M.A.C. to asphalt cements and oils.
A dark brown to black cementitious material in which the predominating constituents are bitumens which occur in nature or are obtained in petroleum processing. In varying proportions, asphalt is a constituent of most crude petroleums.
Generic term for material installed prior to asphalt paving. May be a crushed stone product or asphalt product (see full-depth asphalt pavements). The base material provides the load bearing characteristics of the finished pavement and may vary from 3-4" for a residential driveway to 18" or more for parking areas or roadways. The correct type and amount of base material must be determined and specified prior to paving. Lack of adequate base material is a primary cause of pavement failures.
Common "slang" term for asphalt. However this term should not be used in requesting any specifications or work as the term is widely used with various meanings in different areas. For example sometimes "blacktop" is used to refer to a penetration pavement or hot oil treatment (see fog seal).
Course, Asphalt Base
A foundation course consisting of mineral aggregate, bound together with asphalt material.
Course, Asphalt Surface
The top course of an asphalt pavement, sometimes called asphalt wearing course.
A material that is placed in a pavement crack or joint to fill but not necessarily seal the void created by the crack or joint. Reminder: cracks will still be visible.
A material that has adhesive and cohesive properties to seal cracks, joints or other narrow openings (less than 1 1/2" wide) in pavements against the entrance or passage of water or other debris.
Mechanically produced combination of ingredients which do not normally mix. For example, asphalt emulsions are made by a procedure which mechanically mills the warm asphalt into minute globules, dispersing them in water, and adding a small amount of an emulsifying agent.
A process of applying a highly diluted asphalt emulsion in a fine spray (fog) to a roadway surface. Restores blackness and seals hairline cracks, may prevent or slow oxidation. Not generally used for parking facilities due to tracking.
Full-Depth Asphalt Pavement
The process of constructing an asphalt pavement structure using asphalt products for all components. The base material and surface courses are all made up of appropriately specified grades of hot-mix asphalt in contrast to conventional paving using crushed stone materials etc. There are numerous benefits to this method of construction. The Asphalt Institute has excellent detailed information about this process. A link is available on this site.
H.M.A.C. Hot Mix Asphalt Concrete.
Abbreviation of the proper name for what is commonly referred to as "asphalt", "hot-mix", "blacktop" etc. This term should always be used in specifying asphalt pavement work to avoid any confusion or misinterpretation of the material desired. H.M.A.C. is produced in many different grades from coarse base mixes to specialized mixes for surfacing and repair. In most instances the grades are specified according to state department of transportation guidelines.
The portion of the asphalt paving process where the hot asphalt is actually placed or "laid down" by the paving machine.
A term used to describe the fresh asphalt surface behind the paving machine. Most commonly used to refer to the asphalt during the laydown and compaction phase of construction.
Paving Machine (paver)
The piece of equipment used to place the asphalt or concrete materials in their finished position. In asphalt construction these machines should be the appropriate size for the project. The machine must be able to place a consistently smooth, even finish at the proper depth and provide initial compaction.
Seal Coat or Slurry Seal
Oil based black liquid used to seal coat asphalt.. Recommended every 2-4 years to protect the asphalt. Cracks will still be visible.