How should the application rate for tack at night be adjusted?

When applying tack coat at night, it's essential to adjust the application rate to ensure optimal bonding and curing conditions. The option to multiply by 0.6 is based on the fact that cooler nighttime temperatures can slow down the evaporation of the water in the emulsion, which can impact the performance of the tack coat. A lower application rate helps to ensure that the tack coat is not too thick, which can lead to problems like excessive moisture retention or an inadequate bond if the tack coat does not cure properly.

Adjusting the application rate in this manner is a common practice in asphalt paving to account for environmental factors that can affect the performance of materials. Nighttime conditions often have less heat and sunlight, meaning moisture can linger longer than during the day. Therefore, reducing the rate to 60% of the standard application is necessary to achieve the best results while considering these factors.