How does temperature affect the workability of asphalt?

Temperature plays a significant role in the workability of asphalt, primarily because it affects the viscosity of the asphalt binder. At higher temperatures, asphalt viscosity decreases, allowing it to flow more easily and enabling better manipulation and compaction during the paving process. This improvement in workability at elevated temperatures is crucial for achieving a well-compacted and durable pavement layer.

Conversely, at lower temperatures, the viscosity of the asphalt increases. This can lead to challenges in compacting the asphalt mix effectively, as it becomes stiffer and more resistant to deformation. It becomes more difficult to achieve the desired density and performance specifications when the material is less workable.

The correct answer highlights this relationship between temperature and workability, illustrating that optimal workability is achieved when asphalt is heated sufficiently to ensure smooth handling and effective compaction, defining the appropriate conditions for laying asphalt in construction.