Shrinkage reducing measures for engineering cementitious composites

Abstract

Inhibition measurement of shrinkage of engineering cementitious composites (ECC) was investigated due to typical ECC with higher free drying shrinkage. The effects of expanded admixture (EA), shrinkage reducing admixture (SRA), coarse sand+stone powder (CS+SP) and superabsorbent polymer (SAP) on drying shrinkage and mechanical properties were studied. The experimental results show that ECC incorporating EA, SRA and coarse sand can retain around 60% of the typical ECC’s free drying shrinkage. Superabsorbent polymerl(SAP) can delay the development of free drying shrinkage of ECC at different ages, and the effect of SAP is not distinct like the actions of EA, superabsorbent polymer(SRA) and coarse sand. Significantly, SAP may act as artificial flaw to form a more homogeneous defect system that increases the potential of saturated multiple cracking, hence the ductility of ECC will be improved greatly.

Keywords

engineered cementitious composites (ECC) / shrinkage / SAP

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