Asphalt Explained: How Asphalt Works

What is asphalt? A miracle product.

Asphalt is a combination of sand and rock held together by oil. The oil serves as the glue binding the sand and rock together. Initially, the oil is heated up to roughly 400 degrees when added to the sand and rock material. When the oil cools, it hardens and combines with the sand and rock to create a surface tough enough to withstand a whole lot of car and truck traffic.

In fact, a properly installed asphalt surface has a life expectancy of 10-15 years. Imagine how many cars, trucks, 13 wheelers, etc. use a major asphalt highway over the course of 10-15 years. All on a surface of sand and rock held together by a glue.

In the asphalt material the oil content stays pretty constant. Depending on the use, however, the size of the rock changes. In areas where strength is needed (roads, loading docks, etc.), large rock is used in the asphalt material. The larger the rock used, the stronger the finished surface. The smaller the rock used, the more cosmetically pleasing the finished surface. Small rock is pretty. Large rock is strong.

In an age of technology which constantly changes our society for the better, asphalt is essentially the same as it was nearly 100 years ago. Sand and rock held together by glue.

What a miracle.