The equivalent age of natural curing specimens with the same conditions can be determined according to the environmental temperature and the curing conditions of the structure, according to the following provisions:

1, the corresponding age (excluding the age below 0℃) when the daily average temperature reaches 600℃ d during the curing period (6: 00, 14: 00, 22: 00);

2. It should not be less than 14d or more than 60d.

Below is the temperature record table for your reference.