Asphalt has become the leading paving material in North America, and it is widely used for city streets, residential driveways, tennis courts, airport runways, parking lots, and many other types of pavements. As you can see, asphalt is a very versatile material that provides a durable, economical, and attractive pavement. To the untrained eye, all asphalt pavements may appear to use the same type of paving material, but there are actually several types that have been developed over the years. These include stone matrix, porous, and cold mix asphalts. However, most paving projects use hot mix asphalt, but there are various types of asphalt mixes within this one category.
Why Have Different Types of Hot Mix Asphalts Been Developed?
Hot mix asphalt is a combination of stone, gravel, sand, and asphalt cement. The proportions of the ingredients, the size of the aggregates, and the type and amount of asphalt cement in the mix can affect the performance of the finished pavement, the installation process, and the cost of the product. Some of the performance factors include the smoothness of the pavement, the noise generated by vehicles driving on the pavement, the pavement’s skid resistance, the fuel economy of vehicles using the pavement, and the pavement’s durability. The installation process can be affected by the melting point of the specific type, the stiffness of the mix, and the maximum and minimum thicknesses of the individual layers.
How Does a Pavement’s Intended Use Influence the Type of HMA Chosen?
The choice of a type is often a balancing act between the cost and the properties desired. For example, Type 3 HMA is often chosen for pavements that will have a high volume of slow-moving or standing traffic, including municipal streets, parking lots, and bus stops. Type 3 is an economical choice that offers excellent durability. If the pavement’s aesthetics are paramount, Type 7 HMA may be chosen; it contains the smallest aggregates, giving the pavement an extremely smooth surface. Type 6 HMA has slightly larger aggregates than Type 7, so it is stronger and not quite as smooth. Type 6 and Type 7 are both popular choices for residential driveways, asphalt overlays, and surface courses.
Is the Same Type of HMA Used for All Courses?
Many times, different types can be used to construct an asphalt pavement. For example, the surface course is the top layer of the pavement, so this is often considered the part of the pavement for which smoothness, quietness, and appearance are important. On the other hand, the base layer needs to be extremely strong and highly resistant to temperature changes and compressive stress. The layers between the base and the surface will typically use a type of HMA that provides the best combination of strength, cost, stability, and longevity.
Contact Royal Pavement Solutions to Learn More
Royal Pavement Solutions can help you choose the right type of asphalt for your project. We are a leading provider of asphalt paving, repair, milling, and sealcoating, and we also offer concrete services, parking lot striping, and site work. Our remarkable reputation has been built on our exemplary workmanship, customer service, integrity, and professionalism. We would be happy to provide you with a free quote, so complete the online form to submit your request. If you prefer, call our main office at 844-777-7924.