Durability of Mortars Containing Ground Granulated Blast-furnace Slag in Acid and Sulphate Environment

The paper deals with corrosion resistance of cement mortars with various amounts of ground granulated blast-furnace slag (GGBS). The mortars were tested in the environment containing acids and sulphates corresponding to the aggressive factors acting on concrete in agricultural areas. The strength development of the composites with GGBS is slower; however, the losses in their strength and mass, as well as linear changes, after storing in the aggressive environment, are lesser than for those containing only Portland cement. This can be attributed, most likely, to the favourable changes in the hardened paste microstructure, caused by GGBS presence. The addition makes the structure of the hardened cement paste more compacted, diminishing the porosity and improving the tightness The long-term tests confirm that cement composites containing GGBS can be rational substitutes for ordinary cement concrete in the aforementioned field. However, the subject of the presented research were mortars; the conclusion shall be verified by concrete testing, planned as the next step of the project.