| 摘要 |
<p>PURPOSE: To inexpensively obtain the subject cement having excellent hardening properties, initial and long-term hardness, by blending a blast furnace granulated slag having a specific composition with coal ash, gypsum, Portland cement and an additive such as sodium sulfate in a fixed ratio. CONSTITUTION: (A) Blast furnace granulated slag in an amount of 40-80% comprising 31-36% SiO2 , 12.3-14.47 Al2 O3 , 0.03-0.26% of Fe2 O3 , 28.3-42.42% of Cab, 0.88-1.03% of SO3 , 5.2-5.49% of MgO, 0.16-0.48% of MnO and 0.46-0.82% of TiO2 as constituent components and having 1.6-1.36 CaO/SiO2 ratio is mixed with (B) 3-20% of coal ash discharged from a thermal power station, (C) 4-35%, of gypsum and (D) 2-40% of Portland cement or clinker so as to make 100% of the sum. Then the mixture is blended with a small amount of an additive such as sodium sulfate, aluminum sulfate, sodium carbonate, sodium aluminate or sodium citrate in an outer ratio to give high sulfate slag cement/high early strength slag ash cement.</p> |
