Controlling Shrinkage Cracking

Abstract

The durability of structures—especially concrete bridge decks—is compromised by the presence of cracks mainly associated with concrete shrinkage (drying shrinkage). Research and experience has demonstrated that early-age shrinkage cracking in concrete bridge decks can be significantly reduced if the mixtures have 28-day shrinkage values below 0.030%. While controlling shrinkage to these levels previously required use of low slump mixtures and large, dense aggregates, it is now possible to do so using shrinkage reducing admixtures (SRAs), water reducers, and fibers.