Hydration of sustainable cements based on burnt oil shale

Binders containing conventional additive-free Portland cement, calcined shale, ground granulated blast furnace slag and limestone were examined using experimental methods and thermodynamic modeling. Comparison of bicomponent Portland cement (with limestone) and ternary Portland cement (with calcined shale and limestone) shows that the substitution of limestone for calcined shale significantly reduces porosity and consequently improves the mechanical properties of these ternary compositions. This makes it possible to lower the content of clinker in this system even further (by 10%), as compared with Portland cement with the addition of limestone. Introduction of calcined shale in Portland cement with the addition of slag has a positive effect on the mechanical properties in the early and late hydration periods and the durability of the product after hardening. The results suggest the possibility of further reducing the impact of cementitious binders on carbon dioxide emissions

Author: T. Matschei, T. Schmidt

Section: Science and production

Keywords: blended cement, Portland cement, blast furnace slag, burnt oil shale, limestone, hydration