Title:
Why Sealed Concrete Swells
Author(s):
Konstantin Kovler
Publication:
Materials Journal
Volume:
93
Issue:
4
Appears on pages(s):
334-340
Keywords:
concrete; creep; deformation; drying; evaporation; sealing; shrinkage; swelling; temperature; vapor pressure.
DOI:
10.14359/9819
Date:
7/1/1996
Abstract:
Some possible mechanisms of concrete swelling are reviewed. The role of vapor pressure and its influence on water meniscus curvature in shrinkage and swelling phenomena is underlined. It is shown that the abnormal behavior of drying creep strain in the initial period of drying, when drying creep is ontrary to load direction, indicates the possibility of some additional swelling deformation of sealed concrete in a basic creep test. The periodic shrinkage/swelling material response in cycled tests of drying and sealing is discussed. It is concluded that the observed swelling of sealed concrete subjected to drying prior to sealing can be explained by the release of surface tension of capillary water due to the change of vapor pressure above water menisci.