SILICOMANGANESE SLAG AS A SUPPLEMENTARY CEMENTING MATERIAL

This work investigates the viability of using air-cooled silicomanganese slag as a supplementary cementing material. The studied silicomanganese slag possesses an acid composition with SiO2, CaO, and Al2O3, as main oxides and a MnO-content of nearly 10% by weight. The lime combinability test by thermogravimetry and the results obtained by FT-IR confirm weak pozzolanic properties compared to silica fume and natural pozzolan. Experimental results prove the effectiveness of mechanical activation for replacement levels up to 35% with no significant variation in setting times. The blended cements fulfill all the chemical requirements of the standard specification and do not exhibit any volume instability. The compressive strength reduction for replacement levels up to 15% and for 3, 7 and 28 days of curing is limited to about 10 percent.