Assessment of Water Migration Distance in Internal Curing of High-Strength Concrete
S. Zhutovsky, K. Kovler, and A. Bentur
Appears on pages(s):
autogenous shrinkage; high-strength concrete; internal curing; lightweight aggregate
The paper deals with internal curing of High-Strength Concrete using pre-soaked lightweight aggregate (LWA). The effect of internal curing depends directly on the distance over which the internal curing water can travel. The effectiveness of internal curing is a function of the ratio between the water penetration depth and the paste-lightweight aggregate proximity, which is related to the spacing between the aggregates. Estimates of these parameters were developed in this study, based on a combination of modeling and experimental work. The results indicate that water can penetrate from the LWA into the surrounding matrix to a distance of up to several millimeters during the first seven days of hydration. The water penetration was sensitive to the pore structure of the aggregate, ranging from about 1 to 6 mm, and it was reduced in systems having lower w/b ratio and silica fume by almost a factor of 2.