Which of the following is NOT a factor in determining joint construction?

The determination of joint construction in roadway engineering relies on various environmental and operational factors, but the color of the asphalt mix is not among them.

Traffic conditions influence how joints are constructed to minimize disruption and maintain safety during periods of heavy use. Similarly, time of day can play a role, as construction may be scheduled during off-peak hours to reduce the impact on traffic flow. Weather conditions are critical as they affect the curing process and overall quality of the construction, requiring specific measures to be taken to ensure the material sets properly.

In contrast, the color of the asphalt mix does not have any structural implications or affect the joint's performance or durability. While aesthetics might be a consideration in some contexts, it is not a technical factor in the determination of how joints are constructed. Thus, the color of the asphalt mix does not influence the functional aspects involved in joint construction, making it the correct choice for factors not related to the determination of joint construction.