When it comes to paving projects, having a strong grasp of the terminology can make all the difference. Whether you’re installing a new asphalt driveway, maintaining existing pavement, or speaking with contractors, knowing these terms will help you make informed decisions. This glossary covers the most common terms in the world of paving and driveways.

Aggregate

Crushed stone, gravel, sand, or recycled materials used in asphalt and concrete mixtures to provide strength and stability.

Alligator Cracking

A series of interconnected cracks resembling an alligator’s skin, caused by structural failure in the pavement.

Asphalt Binder

The petroleum-based adhesive that binds aggregate particles together in asphalt mixtures.

Asphalt Cement

Another name for asphalt binder, referring specifically to the refined bituminous product that holds aggregates together.

Asphalt Emulsion

A liquid mixture of asphalt, water, and emulsifying agents, used in applications such as tack coats and sealcoating.

Base Course

The layer of crushed stone or aggregate beneath the asphalt surface that provides load-bearing strength.

Binder Course

An intermediate layer of asphalt between the base course and the surface course, designed for structural support.

Compaction

The mechanical process of densifying soil, aggregate, or asphalt using rollers or tampers to increase load capacity.

Curbing

Concrete or asphalt borders installed along driveways or pavement edges to provide structure and prevent erosion.

Drainage

The system of channels, slopes, and grading designed to move water away from the pavement to prevent damage.

Expansion Joint

A separation in concrete or pavement that allows for movement caused by temperature changes and prevents cracking.

Fatigue Cracking

Another term for alligator cracking, caused by repeated traffic loads on a weakened base.

Fine Aggregate

Sand or crushed stone smaller than 3/8 inch, used in asphalt and concrete mixtures.

Frost Heave

Upward movement of pavement caused by water freezing and expanding beneath the surface.

Geotextile Fabric

A woven or nonwoven synthetic material used to stabilize soil, improve drainage, and reinforce pavement.

Infrared Repair

A method of heating and reworking existing asphalt to blend seamlessly with new material for localized repairs.

Joint

The boundary between two sections of pavement or concrete, designed to control cracking or provide structure.

Load-Bearing Capacity

The maximum weight or pressure the pavement can withstand without failing.

Milling

The process of grinding down the top layer of asphalt to prepare for resurfacing or recycling.

Overlay

A new layer of asphalt applied over existing pavement to restore function and extend service life.

Oxidation

The natural aging process of asphalt when exposed to sunlight and air, leading to brittleness and cracking.

Pavement Fabric

A geotextile placed under asphalt overlays to reduce reflective cracking and strengthen pavement.

Pavement Markings

Painted or thermoplastic lines and symbols applied to paved surfaces for safety and traffic guidance.

Patching

Localized repair of potholes or damaged pavement by removing and replacing the failed section.

Pothole

A depression in pavement formed when water weakens the base and traffic dislodges the surface material.

Raveling

Gradual disintegration of the asphalt surface as aggregate loosens due to binder failure.

Reflective Cracking

Cracks in a new overlay that mirror cracks in the underlying pavement.

Resurfacing

Placing a new layer of asphalt over an existing driveway to restore appearance and durability.

Sealcoating

A thin protective coating applied to asphalt to guard against water, oil, UV rays, and oxidation.

Settlement

Depression or sinking of pavement due to unstable subgrade or inadequate compaction.

Spalling

Surface flaking or breaking in concrete driveways, often caused by freeze-thaw cycles or deicing chemicals.

Subgrade

The native soil or prepared foundation beneath the pavement layers.

Substrate

The material or surface that underlies pavement layers, which may include soil, aggregate, or old asphalt.

Tack Coat

A thin layer of asphalt emulsion applied between pavement layers to improve adhesion.

Thermal Cracking

Straight cracks caused by expansion and contraction from temperature fluctuations.

Wearing Course

The top layer of asphalt pavement, designed to resist traffic wear and environmental damage.

Final Thoughts

A well-built driveway or pavement system relies on more than just asphalt — it depends on the quality of the base, drainage, and ongoing maintenance. By understanding this glossary of paving terms, you’ll be better equipped to discuss options with your contractor, identify problems early, and protect your investment for years to come.