| Slags having three different Si02 : Al20 3 ratios (1.2, 1.9 and 2.6)and three different
CaO contents ( 44%, 39% and 34 %) were prepared. These slags were classified into
nine series, in each of which Al20 3 and Si02 were kept constant and CaO was replaced
by MgO in molecular proportion. The hydraulicity of these slags was estimated from
the compressive strengths of 1:3 mortars, the cements being prepared from 1.8 parts
slag and 1 part hydrated lime by volume. The soundness of the cements produced from
some of these slags and portland cement was also measured. Hydraulicity of slag had a
tendency to decrease when CaO was molecularly replaced by MgO and it practically
did not change when CaO of slag was replaced by MgO on weight basis. Compressive
strength increased with the increase of CaO and Al20 3 content of slag and decreased
with increase of Si02 content. The cements produced from high-magnesia slags were
perfectly sound and did not show any dimensional instability. |
