Materiales de Construcción, Vol 49, No 254 (1999)

Influencia de la adición del BaCO3 sobre la hidratación del cemento portland


https://doi.org/10.3989/mc.1999.v49.i254.449

G. Dumitru
University of Craiova, Romania

T. Vázquez
Instituto de Ciencias de la Construcción Eduardo Torroja (CSIC), Spain

F. Puertas
Instituto de Ciencias de la Construcción Eduardo Torroja (CSIC), Spain

M. T. Blanco-Varela
Instituto de Ciencias de la Construcción Eduardo Torroja (CSIC), Spain

Abstract


The effect of incorporation of BaCO3 in portland cement hydration has been studied. From this study it is inferred that presence of BaCO3 in cements makes them require a higher quantity of mixing water. However, mechanical resistances do not seem negatively affected, for a formation of carboaluminates by chemical reaction between the barium carbonate and the C3A of the clinker appears. The BaCO3 reveals a retardant effect on the setting time, in presence of gypsum as much as in its absence. The BaCO3 with gypsum reacts as BaSO4, a salt of a very high stability. The formation of this barium salt inhibits the formation of ettringite in pastes. Finally, the presence of BaCO3 in cements ensures that no expansive process will occur in sulphatic means either external or internal, for carbonate is going to react with these sulphates and form BaSO4, preventing thus the formation of expansive ettringite.

Full Text:


PDF


Copyright (c) 1999 Consejo Superior de Investigaciones Científicas (CSIC)

Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.


Contact us materconstrucc@ietcc.csic.es

Technical support soporte.tecnico.revistas@csic.es