Expansive properties of the mixture C4ASH12 ? 2CS III. Effects of temperature and restraint

The effects of temperature and restraint upon the hydration and the expansion of $\text{C}{}_4\text{A}\text{S}\text{H}{}_{12}\text{? 2}\text{C}\text{S}$ mixture compacts in different contact solutions have been investigated. Temperatures above 20°C do apparently hinder the formation of an impervious felt-like layer of ettringite around the $\text{C}{}_4\text{A}\text{S}\text{H}{}_{12}$ particles, thus greatly reducing the retarding effect of the lime. An uniaxial restraint of 1 Kg/cm² is enough to reduce sensibly the expansions which remain however high (about 100%). The results can be satisfactorily interpreted by the reaction and expansion mechanism hypothesized in our previous papers.