Asphalt paving may seem like a simple concept composed of a handful of materials, but there are actually a number of different materials that are used. Tucker Paving has decades of experience in the asphalt paving industry, so we’ve defined the basic terms to clear up any confusion.
A Look at Asphalt, Tar, and Bitumen
As in any industry, there are many different terms that are used; sometimes, these words are used interchangeably even though they don’t necessarily mean the same thing, or there can even be regional differences in usage.
- Asphalt. The term “asphalt” can refer to a number of different things. Sometimes, the term asphalt refers to asphalt pavement, or asphalt concrete, which is a combination of bitumen and aggregate mixed together and laid down in a uniform surface to create roads, parking lots, driveways, patios, and other surfaces. Other times, the term asphalt refers to bitumen itself; it can also be called liquid asphalt or asphalt binder.
- Bitumen. Bitumen is a semi-solid form of petroleum that is black, very sticky, and has a high viscosity. It can be found in natural deposits, such as the La Brea Tar Pits in California, or it can be refined from crude oil through the distillation process. In this process, crude oil undergoes a boiling and condensation process to separate the crude oil into different components. Bitumen has many uses, from being used as the binder or glue in asphalt pavement, in waterproofing, in the manufacturing process for roofing materials, and for sealing flat roofs. In the process of making asphalt pavement, bitumen is heated and mixed with aggregate like sand, gravel, stones, and even recycled concrete and synthetic materials. The warm mixture is then applied over a base and flattened to create a uniform, durable surface.
- Tar. Tar is another word that can have many meanings that change based on context, region, or industry. In general, tar is a black or dark brown liquid with a high viscosity that is created from coal, wood, petroleum, and other products through the destructive distillation process. Basically, destructive distillation is a chemical process where a material, such as coal or petroleum, is heated to a high temperature to achieve decomposition of the material. Oftentimes, bitumen is colloquially referred to as tar, though they are different things. There are many different uses for the various types of tars, depending on what the tar was made from. Common uses range from a water repellant or preservative in shipbuilding and roofing to an additive in the food and drink industry. While tar has been used in road construction in the distant past, bitumen and asphalt are today’s standard for roadway construction.
Tucker Paving is an asphalt and concrete paving construction company with over 25 years of experience in the asphalt and concrete paving industry! Contact us online, or call us at (863) 299-2262 for assistance with your asphalt paving project.