CEMENT COMPOSITION

• Main Authors: HIRAO HIROSHI, HOSHINO SEIICHI, AKI TOMOKO, KUROKAWA DAISUKE
• Format: Patent
• Language: English; Japanese
• Published: 07.06.2018
• Subjects: ARTIFICIAL STONE; CEMENTS; CERAMICS; CHEMISTRY; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDINGMATERIALS; CONCRETE; LIME, MAGNESIA; METALLURGY; REFRACTORIES; SLAG; TREATMENT OF NATURAL STONE

PROBLEM TO BE SOLVED: To provide a cement composition having excellent strength development and small dry shrinkage even when containing a large amount of fly ash.SOLUTION: A cement composition which contains a general portland cement clinker ground product having a silica modulus (S.M.) of 1.80-2.40 and a percentage content of free lime of less than 1.0 mass%, plaster, fly ash, and limestone powder having a Blaine specific surface area of exceeding 5,000 cm/g is such that: a ratio of the plaster (SOconversion) is 0.8-3.0 mass% in the total amount 100 mass% of the plaster (SOconversion) and the ground product; a ratio of the fly ash is 7.5-30 mass% in the total amount 100 mass% of the plaster (SOconversion), the ground product, the fly ash, and the limestone powder; a ratio of the limestone powder exceeds 2.5 mass%, and is 10 mass% or less; and a mass ratio represented by(NaO+0.658×KO)/(MgO+SO+TiO+PO+MnO) is 0.20-1.00 in a unit mass of the fly ash.SELECTED DRAWING: None 【課題】フライアッシュを多く含む場合であっても、強度発現性に優れかつ乾燥収縮の小さいセメント組成物を提供する。【解決手段】ケイ酸率（Ｓ．Ｍ．）が１．８０〜２．４０かつフリーライムの含有率が１．０質量％未満である普通ポルトランドセメントクリンカーの粉砕物、石膏、フライアッシュ及びブレーン比表面積が５，０００ｃｍ２／ｇを超える石灰石粉末を含み、石膏（ＳＯ３換算）と上記粉砕物の合計量１００質量％中の、石膏（ＳＯ３換算）の割合が０．８〜３．０質量％であり、石膏（ＳＯ３換算）、上記粉砕物、フライアッシュ、石灰石粉末の合計量１００質量％中、フライアッシュの割合が７．５〜３０質量％、石灰石粉末の割合が２．５質量％を超え、１０質量％以下であり、フライアッシュの単位質量中の、（Ｎａ2Ｏ＋０．６５８×Ｋ2Ｏ）／（ＭｇＯ＋ＳＯ3＋ＴｉＯ2＋Ｐ2Ｏ5＋ＭｎＯ）で表される質量比が０．２０〜１．００であるセメント組成物。【選択図】なし