Asphalt Paving Procedures

Making Asphalt

• Asphalt is made of a mixture of sand, aggregate (rocks of varying sizes), and hot asphalt cement. Asphalt cement is an oil-based product. The mixture is heated to 300 degrees Fahrenheit and is spread when hot, so it is best to have a local company do your asphalt paving to keep the asphalt from cooling in transit. Asphalt cools quickly once spread so it can be driven on shortly after paving is completed.

Preparing a Surface

• A base is dug about 6 to 10 inches deep. The thicker the base the heavier the vehicles that can be driven over it. The soil is made as compact as possible and cleared of debris. The base is made level. Crushed gravel and larger aggregate are used to fill the base. Coarser aggregate is used if the base is in an area or composed of soil such as clay that has poor drainage. The gravel is graded or spread evenly.

Pouring the Asphalt

• The asphalt is delivered to the site and transferred to a vehicle which keeps the mixture moving so the components don't separate or congeal. Hot asphalt is poured over the gravel and aggregate. An asphalt spreader is used to spread the hot mixture. A paver is then used to mix in a layer of gravel and smooth out the pavement. Compactors are used to compact the pavement and make it more dense.

Keeping Up Appearances

• Asphalt is durable and long-lasting, but some upkeep is required to keep it looking its best. A sealer can be applied when the paving is done. Sealer keeps the asphalt looking shiny, and fills in small cracks that appear over time. Sealer needs to be reapplied every few years. Larger cracks can also be repaired. The cracks are filled in and patched with hot asphalt cement, which makes the patches almost invisible.