Influence of permeability-reducing admixtures on water penetration in concrete

Copyright © 2017, American Concrete Institute. All rights reserved. An experimental investigation was carried out on concrete into the effectiveness of integral permeability-reducing admixtures as possible alternatives to the traditional external waterproofers. The efficiency of hydrophobic water repellents and crystalline pore blockers were evaluated in concretes incorporating fixed water-cementitious materials ratio (w/cm) and different cementitious material types covering OPC, fly ash, and granulated blast-furnace slag. Three different test methods were employed to evaluate the water penetration resistance of concrete. To isolate the benefits that are achieved by varying the mixture design parameters, statistical factorial analysis of variances was carried out to discover the significance of each variable. Results indicated that the effect of w/cm and cementitious material is more pronounced compared to the addition of permeability-reducing admixtures. It was also demonstrated that the admixtures can be effective in reducing water penetration; however, their effect is varied in different mixtures. Caution must be exercised when using such admixtures in different concrete mixtures