What is Hot Mix Asphalt?Hot mix asphalt is referred to by several names. In different parts of the country it is also referred to as bituminous concrete, hot plant mix, asphalt concrete and blacktop. Hot mix asphalt is composed of aggregate bound together into a mix by asphaltic cement. The aggregates total ninety-three (93) to ninety-seven (97) percent by weight of the total mixture and are mixed with 3% to 7% asphalt cement. It is manufactured in a central mixing plant, where the asphalt and aggregates are heated to a temperature of approximately 300 degrees Fahrenheit, properly proportioned and then mixed. The completed paving mixture is hauled by special trucks to the paver where it is placed into a smooth layer and compacted by rollers while still hot. Asphalt pavements are constructed in multiple courses placed directly on the sub grade, or on a sub base, and is usually placed by a machine. Sometimes asphalt will be placed by hand when it is impractical to use a machine. |
