A PROPOSAL OF TEMPERATURE-TIME FUNCTION ON THE STRENGTH DEVELOPMENT OF CONCRETE UNDER SUB-ZERO TEMPERATURE

Compressive strength development of concrete is essential for cold weather concreting. It is well known that strength development of concrete under the freezing point is much delayed. But the evaluation method has not been shown clearly yet. Therefore when average outside air temperature is under the freezing point planning method of cold weather concreting is not clear. We focus on the concept of equivalent maturity method proposed by Sudo, attempted to propose a time-temperature function representing the strength development of concrete under sub-zero temperature. As a result, we have proposed a function to calculate the maturity under sub-zero temperature. The proposed function could explain the strength development of the concrete exposure in winter