Effect of a Rheology Modifier on Settlement Cracking of Concrete

Abstract

Thirty-one test specimens containing concrete with a 27 percent cement paste content and a water-to-cement ratio of 0.45 were used to evaluate the effectiveness of a rheology modifier in the form of a dry viscosity modifying admixture (dosed at 0.05% of mixture material dry weight) on settlement cracking. The results show that settlement cracking increases as the slump of the mixture increases. The addition of the viscosity modifying admixture reduces settlement cracking compared to the mixtures without the addition.