What is the minimum required atmospheric temperature when placing hot mix asphalt concrete?

The minimum required atmospheric temperature for placing hot mix asphalt concrete is 4°C. This temperature is critical because if the ambient conditions are too low, it can adversely affect the workability and adhesion of the asphalt. When the temperature drops below this threshold, the asphalt mixture may not compact effectively, which could lead to inadequate density and potentially compromise the longevity and performance of the pavement.

A temperature of 4°C ensures that the asphalt remains sufficiently workable, facilitating proper compaction and embedding of aggregates. This optimal temperature helps achieve a good bond between the asphalt and the aggregate, which is essential for the durability and strength of the final pavement surface. Adhering to this guideline supports overall asphalt performance and longevity.