Abstract
In this study, the authors investigate the volumetric change of hardened cement paste when the dried specimens under various conditions are soaked in different polar or non-polar liquids. The objective is to comprehend the dominant phenomena to cause the shrinkage of the cement paste based on liquid characteristics. When the oven dried specimens are submerged in various liquids other than water, the shrinkage due to the oven dry is hardly recovered while the shrinkage of the specimens is almost recovered by submerging in water. This could be because the adsorption of the liquids to cement paste is much smaller than that of water and could have little reduction of the solid surface energy of cement paste. The large shrinkage is observed after moist-cured specimens are soaked in polar solvents which are dissolved in water. It could be attributed to the decrease of disjoining pressure and increase of solid surface energy due to the absorption of liquid water and adsorbed water in fine pores and C-S-H gel. The shrinkage of partially dried specimens is recovered soon after soaking in both polar and non-polar liquids. It is speculated that the decrease of capillary tension or the increase of disjoining pressure cause the immediate recovery of the shrinkage.
