Road construction vocabulary

Roads are made up of four layers. These include: 

Layers of road construction

• Sub-grade: Native soil underneath a road.
• Sub-base: Layer of aggregate materials on top of the sub-grade
• Base (also base course): Layer of material under the surface course.
• Surface (also surface course): The upper layer of the road.

The surface can consist of asphalt, concrete, cobblestones, tiles or earth materials. Asphalt and concrete are the most common surface materials.

• Asphalt: Black or brown sticky substance, mixed with crushed stone, sand or gravel, which is used for construction of road surfaces.
• Concrete: Building material created by mixing together cement, sand, gravel and water.
• Cobblestone: Rounded stone used to make the surfaces of roads.
• Tile: Concrete or baked clay of various shapes and colors, used for covering walls, roofs or surfaces.
• Earth materials: Soil, sand, gravel or granular products.

Road drainage

• Gutter: Channel at the side of a road to collect rainwater and carry it away from the roadway.
• Ditch: Long hole dug at the side of a road to channel water.
• Culvert: Tunnel that channels water under the roadway from one side to the other.

Road surface marking

• Yellow lines: Lane of traffic moving in opposite directions.
• White lines: Lane of traffic moving in the same direction.
• Solid lines: Unsafe to cross the line
• Broken lines: Safe to cross the line if the way is clear.

Road machinery

• Grader: Vehicle with a long blade used for grading surface.
• Roller: Heavy vehicle used to make surface flat by compacting soil, gravel, asphalt, or concrete.
• Paver: Vehicle used to lay asphalt or concrete on surface.

BrE	AmE
Road surface	Pavement

Sentence examples:

Culverts help control water flow.

The ditches play important roles in agriculture.

Graders are often used to remove snow.

Cobblestones date back to ancient times.