Methodology for including the age effect of concrete with SCMs in results from accelerated testing

Concrete cubes with a side length of 100 mm were coated (with the exception of one face) and placed in a carbonation chamber (10 vol% CO2, 20°C and 60% RH). After 2, 4, 8, 16 and 24 weeks, the carbonation depth was measured by spraying phenolphthalein solution on a fresh sawn surface. From the evolution of the carbonation depth (x) (x0: initial value) in function of square root of time (√t), the carbonation coefficient (A) could be calculated (Eq. 1).