Asphalt, Concrete Glossary of Terms

ADA Ramp — A wheelchair ramp in compliance with the American’s with Disability Act (ADA) of 1990 (must conform to appropriate design specifications).

Alligatoring — A surface symptom associated with decayed asphalt whereby there is heavy and comprehensive cracking in a concentrated area. Name derives itself from the similarity in appearance to the back of an alligator. The proper remedy for asphalt in this condition is to remove it, re-compact the sub-base gravel, and replace with new asphalt.

ArmorSeal — A slurry sealer (or asphalt sealer) product made by ArmorSeal Corporation in Tacoma, WA.

Asphalt — A pavement surface consisting of aggregates, fines, and a binder of liquid asphalt. The material is applied hot and is cured once it cools.

Berm — A short, narrow asphalt bump used to direct water flow away from sensitive areas and toward collection areas such as catch basins or trench drains or large permeable surfaces.

Broom finish — A technique of applying the final touch—or “finish”—on the surface of a concrete pour by applying light brush strokes in a uniform direction. This is by far the most common finishing technique for concrete flatwork.

Catch Basin — A rectangular or circular grated unit designed to capture rainwater at the surface and carry it to the underground system of storm drains.

Concrete — A pavement surface consisting of cement, aggregates, water, and chemical admixtures. The material is applied cold and is cured once the water evaporates out.

Crack Filling — The process of applying a pourable product into the joint of exposed asphalt surface cracks to prevent moisture penetration and, ultimately, more severe pavement damage.

Crushed rock — A mixture of aggregates (of varying sizes, depending upon the intended use) and fines typically used in the sub-base layer immediately below the surface layer of asphalt or concrete.

Curb and gutter — A combination of vertical curbing and horizontal gutter (flush with street level) which serves to guide water into storm drains. This style uses traditional concrete mix, unlike an extruded curb which uses a drier mix.

Dry Well — A covered underground pit used to collect and slowly dissipate water into the surrounding soil if an existing storm water system is not available. Water is collected at the surface through catch basins or trench drains, routed with pipe underneath the surface and into the cube-shaped well. Once in the well, the pipe becomes perforated and extends around the perimeter of the well (several inches inward from the actual perimeter) to allow the water to slowly dissipate throughout the well. The well is filled with drain rock, surrounding the pipe. Dry wells are intended for low volumes of water flow such as driveways. Depending on the type of soil, they may or may not be a good alternative.

Durafil — A heat-stabilized rubberized crack filler used to fill asphalt cracks. The material is heated to approximately 400 degrees, poured into the crack, and then torched to ensure a proper bond and surface smoothness. It will then cool and harden inside, preventing moisture penetration.

Exposed aggregate finish — A technique whereby the finished concrete product has “exposed” rocks or “aggregate” protruding on the surface. Considered more decorative than the more common “broom finish.”

Extruded curb — The most common type of curb which uses a dry concrete mixture allowing for immediate finishing. Placed with a mechanized extruded curbing machine.

Freeze-thaw cycle — The process whereby temperatures fluctuate repeatedly between above-freezing and below-freezing. These temperature differences promote the expansion and contraction of surfaces such as asphalt and concrete, accentuating decay and damage.

Hot Mix Asphalt (HMA) — The mixture used in construction of asphalt pavement surfaces. Can have different sized aggregates and specifications, depending on the weight-load-bearing capacity necessary.

Overlay — A process of applying a new layer of asphalt on top of a damaged or decayed layer. Not considered to be as structurally sound as R&R (repair and replacement), but a cheaper alternative. There are various types of overlays including: straight overlay, Petromat overlay, and grind overlay.

Patching — The process of removing only localized areas of existing asphalt decay or damage and replacing with new asphalt. This term is used to differentiate from “paving” which is the application of new asphalt.

Paving — The installation of a new asphalt surface.

PetroSeal — A primer applied, prior to seal coating, to areas where there are oil spots because a water-based sealer cannot adhere well to an oily surface. This remedy is not considered to be as effective as removal and replacement of the contaminated asphalt.

R&R — Removal and replacement. This term can apply to both asphalt and concrete and is used to differentiate from an alternative process whereby the new material is placed over the old material (overlay). An R&R repair provides better structural integrity because it allows for inspection and compaction of the sub-base.

Root damage — Surface damage to parking lots, sidewalks, and curbs caused by tree or plant roots. An appropriate remedy often involves cutting the tree roots. A certified arborist should sometimes be consulted depending on the age, size, and variety of the tree or plant involved.

Rubberized crack filler — A hot-apply product used to fill asphalt cracks (similar to caulk in a house). The material is heated to approximately 400 degrees, poured into the crack, and then flattened with a squeegee to flush with the adjacent pavement surface or slightly recessed. It will then cool and harden inside, preventing moisture penetration.

Sawcutting — The process of using a diamond-bladed circular saw to cut a straight edge in asphalt or concrete patching. Used for an aesthetically-pleasing finished product and also to promote better structural integrity.

Sealing/Seal Coating — A process of preventative maintenance and beautifying to asphalt surfaces which promotes the lifespan of the underlying asphalt. The process Involves applying a cold-apply, high-solids, asphalt-based liquid slurry sealer to the surface of the asphalt.

Striping — The process of applying traffic paint to a parking area including line stripes, stencils, numbering, and curb painting.

Sub-base — The layer(s) rock underneath a surface of asphalt or concrete. Usually involves a layer of crushed rock in the layer immediately below the surface layer. There are also other more specialized types of sub-bases, such as Asphalt Treated Base (ATB) and Controlled Density Fill (CDF). The sub-base should be engineered for the appropriate load-bearing capacity.

Tar Seal — A hot-apply product applied to the perimeter of a new asphalt patch to prevent moisture penetration between the new seams. Similar to rubberized crack filler, but not identical. Tar seal is more viscous.

Thermoplastic — A form of pavement marking used as an alternative to traditional paint striping for heavy traffic areas. It is applied using a heat-bonded process. It is used on interstate highways and at intersections on public thoroughfares for things such as arrows, stripes, and crosswalk bars. This product has an expected lifespan of approximately 5-7 times that of paint.

Traffic Paint — A solvent-based (or oil) paint designed specifically for application on streets and parking lots. This product is applied through a gas-powered, airless paint sprayer.

Trench Drain — A long, narrow trench used to collect water through a grated opening at the surface. Water is then channeled through the sub-surface pipe and routed into an existing storm drain system or discharged downhill from the trench at the ground surface.

Trip Hazard — An irregularity at the surface caused by roots, water, or other sources, which can increase the likelihood that a pedestrian may trip or fall. An important consideration for property owners because of potential liability lawsuits.

We hope you found our glossary both informational and helpful! For more information on asphalt and concrete please visit our blog.