Hot mix asphalt (HMA) is a mixture of aggregate (crushed stone, gravel, sand) and asphalt binder heated and mixed at high temperatures (300-350°F). It's the most common pavement material for roads, highways, and parking lots due to its durability and weather resistance.
Standard HMA density is 145-150 lbs per cubic foot, or approximately 110-115 lbs per square yard per inch of thickness. This can vary based on mix design, aggregate type, and compaction level.
What are the different types of hot mix asphalt?
Common HMA types: Dense-Graded (standard roads), Stone Matrix Asphalt (SMA) for heavy traffic, Open-Graded for drainage, Polymer-Modified for high-stress areas, and Warm Mix for lower temperature placement.
How thick should hot mix asphalt be?
Residential driveways: 2-3 inches. Parking lots: 3-4 inches. Residential roads: 4-5 inches. Collector roads: 5-6 inches. Highways: 6-12 inches depending on traffic loads and base conditions.
What is the difference between hot mix and cold mix asphalt?
Hot mix asphalt is produced at 300-350°F, requires professional equipment, and provides durable, long-lasting pavement. Cold mix is produced with emulsified or cutback asphalt, can be used in wet/cold conditions, and is typically used for temporary patches.