CALCIUM HYDROXIDE IN CEMENT MATRICES: PHYSICO-MECHANICAL AND PHYSICO-CHEMICAL CONTRIBUTIONS

摘要

Calcium hydroxide (CH) represents a significant volume of the products formed from the cement-water reaction. The extent to which the CH phase contributes to the engineering integrity and volume stability of cement-based binders is however moot. Evidence in support of the view that calcium hydroxide has a significant role in determining the mechanical performance and volume stability of cementitious materials is presented. The elastic properties and fracture behavior of CH and CH ― C-S-H mixtures are described. Volume stability of CH is described with reference to water sorption isotherms (CH) and length change measurements in various solvents and salt solutions. A dissolution-based expansion mechanism in which CH plays a major role is described for the behavior of cement binders in aggressive media.