Which condition is NOT a concern for concrete in cold weather?

The high liquid-to-cement ratio is not typically a concern for concrete in cold weather, as it pertains more to concrete's workability, strength development, and durability under normal conditions rather than temperature effects. In colder temperatures, the issues most commonly arise from the risk of freezing, which can severely impact the curing and setting of the concrete, leading to weakened structural integrity.

Concerns like air temperature falling below 40°F and concrete freezing within the first 12 hours are critical because low temperatures can impede the hydration process, which is essential for achieving the desired strength and durability. Humidity levels may influence the curing process but are not directly tied to temperature as much as the liquid-to-cement ratio is. Therefore, while a high liquid-to-cement ratio can have various implications for concrete quality, it does not specifically relate to the peculiar challenges presented by cold weather conditions.