What is the minimum air and surface temperature for placing the final layer of surface mixes containing recycled asphalt shingles?

The minimum air and surface temperature for placing the final layer of surface mixes containing recycled asphalt shingles is 50°F. This temperature threshold is critical because it ensures proper adhesion and compaction of the asphalt mixture. At lower temperatures, the performance characteristics of asphalt mixes, such as workability and the ability to bond effectively, can be compromised.

This temperature guideline is based on research and best practices in asphalt paving, as it reflects the conditions necessary for the materials to achieve optimal performance once set. Ensuring that the temperature is maintained at or above this minimum helps in preventing issues such as cracking, poor compaction, and reduced durability of the asphalt surface, which can ultimately affect its lifespan and performance.