Evaluation of Internally Cured Concrete for Paving Applications

Abstract

This paper evaluates the use of Internally Cured Concrete (ICC) on Interstates, residential, industrial and other concrete pavement projects from the perspective of design, construction, longevity, curling, durability and life cycle cost. ICC is a concrete mixture in which a portion of the intermediate, and/or fine aggregates (for example, 30 percent of sand) is replaced with similar sized prewetted lightweight aggregate (LWA). Internal curing (IC) is a means to provide hydrating concrete adequate moisture from within the mixture (slab) to replace water lost due to chemical shrinkage. IC may also restore, at least partially, the moisture that escapes through evaporation. IC, which naturally takes place in LWA concrete, has been designed into conventional concrete to release moisture well after placement. ICC has also demonstrated good constructability on field. ICC has shown good durability results in reducing early age shrinkage and associated plastic shrinkage cracking as well as other random cracking on several bridge decks and a few concrete pavement projects. ICC has also demonstrated some benefits in material properties favorably impacting pavement performance that are presented in this paper.