What type of tack is recommended for use at night?

The recommended type of tack for use at night is typically one that provides excellent adhesion and is workable in lower temperature conditions, which can be more prevalent at night. PG 52-28 is designed for more moderate climate conditions and has a lower high-temperature binder grade compared to others listed, making it more suitable for cooler nighttime applications. This ensures that the asphalt does not become overly fluid when temperatures drop, preventing potential issues with the tack adhering properly to the surface.

The other options, while suitable under certain conditions, do not offer the same performance in cooler temperatures typical of nighttime work. Higher-grade asphalts like PG 64-22 and PG 70-22 are formulated for warmer conditions and might become too viscous when temperatures drop, which affects their ability to bond with the surface. PG 58-28, while it has a lower high-temperature grade compared to PG 64-22 and PG 70-22, does not provide the same optimal performance as PG 52-28 for nighttime applications.

Understanding the specific applications and temperature ranges for each type of tack is essential for effective asphalt paving, particularly in varying day and night temperatures.