A New Look at the Problem of Drying Creep of Concrete under Tension

The main possible physical mechanisms of drying creep of concrete under compression and tension and their limitations are considered herein. The phenomenological approach describing drying creep of concrete as a sum of shrinkage-induced creep and creep-induced shrinkage, presented by the writer in a previous work, is revised and corrected. In view of the new data, the experimental results obtained for load-free sealed concrete specimens subjected to drying prior to sealing indicate swelling behavior due to the change of vapor pressure above water menisci. Such a swelling deformation should be subtracted from the basic creep strain measured in sealed specimens. After this correction, the curve of drying creep under tension loses its “abnormal” character and becomes the regular drying creep curve. The mechanism of drying creep based on the stress-induced shrinkage is called into question, because the corrected drying creep strain represents the extra creep (but not the extra shrinkage) component within the whole range of loading duration.