Influence of Locally Produced Waterproofing Admixture (Sternson 300) on Concrete Absorption and Strength

Abstract

In this work, the influence of waterproofing admixture of stearate type on thewater reduction of concrete mix (1:2:4) for a given workability, (50+5)mm slump wasinvestigated. Results indicated that this admixture has a little influence on the waterreduction of concrete. Therefore this admixture cannot be considered as a waterreducer since it does not conform with the requirements of type (A) admixture inaccordance with (ASTM-C494-98 Type A)[1].The same influence on the compressive strength of concrete (fcu) at various ages(7,28,60 and 90) days was studied. Results showed that the use of this admixture atrecommended dose specified by the manufacturer has no significant effect on thecompressive strength of concrete. On the other hand, overdoses of this admixture leadto a considerable reduction in the compressive strength.The efficiency of this admixture at different doses in reducing the total waterabsorption of concrete and the absorption of water by the capillary action was alsoexamined. Results revealed that this admixture is not effective in reducing the waterabsorption with all doses used in this work and at different ages compared withreference mix without admixture.