Cement additive and cement composition
AssigneesTaiheiyo Cement Corporation, Dc Co., Ltd.
InventorsHiroshi Hirao, Kazuo Yamada, Kiyoshi Koibuchi, Nobukazu Nito
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Abstract
A cement additive contains industrial waste and has the effect of inhibiting formation of monosulfate in a hardened cementitious material. The cement additive contains specifically calcium carbonate, gypsum and coal ash and/or blast-furnace slag powder. This enables efficient use of industrial waste, allows inhibiting monosulfate formation in the hardened cementitious material, and allows producing a hardened cementitious material having good durability (sulfate resistance).
Claims12
A cement additive containing industrial waste and having an effect of inhibiting monosulfate formation in a hardened cementitious material, said cement additive comprising calcium carbonate, gypsum, and blast-furnace slag powder without coal ash,
- wherein said calcium carbonate is blended in an amount of 6 to 160 parts by weight and said gypsum (anhydrous basis) is blended in an amount of 5 to 150 parts by weight relative to 100 parts by weight of said blast-furnace slag powder, and a blending ratio (weight basis) of said gypsum and said calcium carbonate is 1:1.1 to 15.
A cement additive containing industrial waste and having an effect of inhibiting monosulfate formation in a hardened cementitious material, said cement additive comprising calcium carbonate, gypsum, blast-furnace slag powder and coal ash,
- wherein said calcium carbonate is blended in an amount of 0.5 to 160 parts by weight and said gypsum (anhydrous basis) is blended in an amount of 5 to 150 parts by weight relative to 100 parts by weight of said coal ash and said blast-furnace slag powder, and a blending ratio (weight basis) of said gypsum and said calcium carbonate is 1:0.1 to 15.
Dependencies are inferred from the claim text.