Road Paving Materials
Definitions
Macadam: Type of road construction. Not a material. The name is eponymously named after the inventor of modern road surfaces, John McAdam.
- Construction is where crushed stone layers of angular stone are layered and compacted. Sub-base of crushed stone or gravel is covered by fine aggregate. Then the Asphalt is 2-3” thick generally.
Asphalt: Also known as Bitumen. A dark black and sticky form of petroleum. It can be found in natural deposits but is also a refined product.
Introduction
Roads and parking are most frequently constructed from concrete or asphalt, however there are multiple variations within each material and different designs that would be beneficial in different circumstances.
History and Breadth
Additionally to note is that the material used for paving roads has greatly adapted and changed to the technology of time. In the past brick, wood, and other materials have given way to materials with more longevity. This occurs because roads are constantly being fixed, developed and expanded. And given the breadth and cost of the system, it makes sense to constantly invest in updated technology.
- Currently there are more than 4.1 million miles of roads across the United States alone (2018 data).