Date of Award:


Document Type:


Degree Name:

Master of Science (MS)


Civil and Environmental Engineering

Committee Chair(s)

William A. Cordon


William A. Cordon


The use of water-reducing admixtures in concrete has grown continuously since their introduction over 25 years ago, with a present estimated usage in the production of 25 million cubic yards of concrete annually in the United States alone. Opposition to anything added to concrete, other than cement, aggregates, and water, is gradually disappearing, and considerable recognition is being given to the value of using other ingredients.

The research contained in this study may be divided into two portions: tests to determine the rate of volume change of cement paste and compressive strength tests to indicate the effect of moist curing on rate of strength gain. Both portions were carried out with plain (no water reducer added) and treated (containing water reducer) mixes.

The results indicate that a much greater volume change occurs in admixture-treated cement pastes than in plain pastes. The theory is advanced that this greater volume change, when a water-reducing ad~ixture is used, represents a more rapid combination of cement and water. This supports the strength test results showing that water reducers lead to high early compressive strength of concrete.