3 Things You Probably Didn’t Know About Asphalt Paving
Asphalt Is A Natural Substance
Everyone knows something about asphalt paving. We walk on it, drive on it and look at it every day, but most of us don’t know what it really is and how asphalt does what it does.
Asphalt has been used for thousands of years. The Romans used it for waterproofing and glue. We don’t think asphalt is a natural product, but asphalt does occur naturally in places like the LaBrea “tar pits” in SoCal and a Trinidad lake.
Most of the asphalt we use for paving purposes comes from crude oil, and that fact has given asphalt a “black eye” in environmental circles. But the oil to create asphalt is distilled, and all the volatile elements are removed.
What’s left is called asphalt cement or bitumen. Bitumen is the word used to describe liquid asphalt in Europe and Canada. When sand, stone and gravel are added to the asphalt cement, paving asphalt is born. Most of us don’t realize it, but hot asphalt is sticky, and it will bend, stretch and flex without breaking.
There Are Several Different Grades Of Asphalt
Not all asphalt is created equally. Soft asphalt is used in colder areas of the country, and a harder mixture is used in hot climates. Polymers are added to asphalt mixtures that are used for heavy duty projects like airports or city streets. Polymers are also used in areas where the temperatures drop well below freezing, or in areas where the temperature is well above 100°F.
Mixing different grades of asphalt takes a little ingenuity as well. Forget about mixing asphalt at normal temperatures. In order to make it thin enough to mix with aggregates, it has to be heated, emulsified in water or diluted with a solvent. One important fact to remember is, asphalt is not tar. Tar is a coal product, and there is no coal used when making different grades of asphalt.
Water Is Asphalt’s Number One Enemy
All asphalt tends to crack. That’s why sealers are used. There are two types of cracks: Stress Cracks and Shrinkage Cracks. Asphalt cracking is caused by oxidation. Asphalt shrinks like dried mud, and when it does, slight cracks appear on the surface.
Water exacerbates the cracks. If the asphalt cracks are not sealed, water will erode them and then destroy the base material. If asphalt driveways and roads were sealed on a regular basis, water would not be the number one nemesis of asphalt.
Looking for asphalt paving experts in the Ramsey area? Call McFarlane Asphalt at (201) 327-5258 for quality service you can trust!