Methods for the treatment of non-hardened cement compositions, especially returned concrete, and admixtures suitable to be used in such methods. The admixtures include modified starch and a sugar. Also, solid granules obtained by the methods and fresh concrete or mortar utilizing solid granules thus obtained.

Methods for the treatment of non-hardened cement compositions, especially returned concrete, and admixtures suitable to be used in such methods. The admixtures include modified starch and a sugar. Also, solid granules obtained by the methods and fresh concrete or mortar utilizing solid granules thus obtained.

Methods for the treatment of non-hardened cement compositions, especially returned concrete, and admixtures suitable to be used in such methods. The admixtures include modified starch and a sugar. Also, solid granules obtained by the methods and fresh concrete or mortar utilizing solid granules thus obtained.

The present invention provides an admixture for concrete with an excellent flow retainability over a long time of 120 minutes until the placement of the concrete without loss of strength, and in which a workable time and constructability are obtainable because a suitable setting time is obtained, and in which bleeding is suppressible.

The admixture for concrete comprises a lignin derivative (A), a copolymer having a hydrolysable group (B) and a (meth)acrylic-based viscosity adjusting component (C), wherein the copolymer having the hydrolysable group (B) is a copolymer of at least two monomers consisting of an ethylenically unsaturated monomer having hydrolysability (b1) and an ethylenically unsaturated monomer having a polyalkyleneoxide ether chain (b2).

The present invention provides an admixture for concrete with an excellent flow retainability over a long time of 120 minutes until the placement of the concrete without loss of strength, and in which a workable time and constructability are obtainable because a suitable setting time is obtained, and in which bleeding is suppressible.

The admixture for concrete comprises a lignin derivative (A), a copolymer having a hydrolysable group (B) and a (meth)acrylic-based viscosity adjusting component (C), wherein the copolymer having the hydrolysable group (B) is a copolymer of at least two monomers consisting of an ethylenically unsaturated monomer having hydrolysability (b1) and an ethylenically unsaturated monomer having a polyalkyleneoxide ether chain (b2).

A limestone calcined clay cement construction composition comprises a) a cementitious binder comprising one or more calcium silicate mineral phases and one or more calcium aluminate mineral phases, and having a Blaine surface area of at least 3800 cm.sup.2/g, in an amount of 180 to 400 kg per m.sup.3 of the freshly mixed construction composition; b) a supplementary cementitious material having a Dv90 of less than 200 μm, in a total amount of 50 to 100 parts by weight, relative to 100 parts by weight of cementitious binder a), the supplementary cementitious material comprising (b-1) a calcined clay material and (b-2) a carbonate rock powder in a weight ratio of (b-1) to (b-2) in the range of 0.5 to 2; c) optionally, an extraneous aluminate source; d) a sulfate source; and e) a polyol in an amount of 0.3 to 2.5 wt.-%, relative to the amount of cementitious binder a). The composition contains available aluminate, calculated as Al(OH).sub.4.sup.−, from the calcium aluminate mineral phases plus the optional extraneous aluminate source, per 100 g of cementitious binder a), in a total amount of at least 0.08 mol, if the amount of cementitious binder a) is in the range of 180 to less than 220 kg per m.sup.3 of the freshly mixed composition, at least 0.06 mol, if the amount of cementitious binder a) is in the range of 220 to less than 280 kg per m.sup.3 of the freshly mixed composition, and at least 0.05 mol, if the amount of cementitious binder a) is 280 kg or more per m.sup.3 of the freshly mixed composition; and the molar ratio of total available aluminate to sulfate is 0.4 to 2.0. The construction composition further comprises f) an ettringite formation controller comprising (i) glyoxylic acid, a glyoxylic acid salt and/or a glyoxylic acid derivative; and (ii) at least one of (ii-a) a borate source and (ii-b) a carbonate source, wherein the carbonate source is selected from inorganic carbonates having an aqueous solubility of 0.1 g.Math.L.sup.−1 or more, organic carbonates, and mixtures thereof; and g) a co-retarder selected from (g-1) α-hydroxy monocarboxylic acids and salts thereof, (g-2) phosphonic acids and salts thereof, (g-3) polycarboxylic acids and salts thereof, and mixtures thereof. The limestone calcined clay cement construction composition is a reduced carbon footprint composition and exhibits high early strength, high final strength, sufficient open time and high durability. Ingredients of the construction composition are abundantly available.

A limestone calcined clay cement construction composition comprises a) a cementitious binder comprising one or more calcium silicate mineral phases and one or more calcium aluminate mineral phases, and having a Blaine surface area of at least 3800 cm.sup.2/g, in an amount of 180 to 400 kg per m.sup.3 of the freshly mixed construction composition; b) a supplementary cementitious material having a Dv90 of less than 200 μm, in a total amount of 50 to 100 parts by weight, relative to 100 parts by weight of cementitious binder a), the supplementary cementitious material comprising (b-1) a calcined clay material and (b-2) a carbonate rock powder in a weight ratio of (b-1) to (b-2) in the range of 0.5 to 2; c) optionally, an extraneous aluminate source; d) a sulfate source; and e) a polyol in an amount of 0.3 to 2.5 wt.-%, relative to the amount of cementitious binder a). The composition contains available aluminate, calculated as Al(OH).sub.4.sup.−, from the calcium aluminate mineral phases plus the optional extraneous aluminate source, per 100 g of cementitious binder a), in a total amount of at least 0.08 mol, if the amount of cementitious binder a) is in the range of 180 to less than 220 kg per m.sup.3 of the freshly mixed composition, at least 0.06 mol, if the amount of cementitious binder a) is in the range of 220 to less than 280 kg per m.sup.3 of the freshly mixed composition, and at least 0.05 mol, if the amount of cementitious binder a) is 280 kg or more per m.sup.3 of the freshly mixed composition; and the molar ratio of total available aluminate to sulfate is 0.4 to 2.0. The construction composition further comprises f) an ettringite formation controller comprising (i) glyoxylic acid, a glyoxylic acid salt and/or a glyoxylic acid derivative; and (ii) at least one of (ii-a) a borate source and (ii-b) a carbonate source, wherein the carbonate source is selected from inorganic carbonates having an aqueous solubility of 0.1 g.Math.L.sup.−1 or more, organic carbonates, and mixtures thereof; and g) a co-retarder selected from (g-1) α-hydroxy monocarboxylic acids and salts thereof, (g-2) phosphonic acids and salts thereof, (g-3) polycarboxylic acids and salts thereof, and mixtures thereof. The limestone calcined clay cement construction composition is a reduced carbon footprint composition and exhibits high early strength, high final strength, sufficient open time and high durability. Ingredients of the construction composition are abundantly available.

A construction composition comprises a) a cementitious binder comprising one or more calcium silicate mineral phases and one or more calcium aluminate mineral phases; b) optionally, an extraneous aluminate source; c) a sulfate source; d) an ettringite formation controller comprising (i) glyoxylic acid, a glyoxylic acid salt and/or a glyoxylic acid derivative; and (ii) at least one of a borate source and a carbonate source, wherein the carbonate source is selected from inorganic carbonates having an aqueous solubility of 0.1 g.Math.L.sup.−1 or more, organic carbonates, and mixtures thereof; and e) a polyol in an amount of 0.2 to 2.5 wt.-%, relative to the amount of cementitious binder a). The composition contains 0.05 to 0.2 mol of total available aluminate, calculated as Al(OH).sub.4.sup.−, from the calcium aluminate mineral phases plus the optional extraneous aluminate source, per 100 g of cementitious binder a); and the molar ratio of total available aluminate to sulfate is 0.4 to 2.0. The construction composition exhibits high early strength and sufficient open time. The advantageous effects are readily achievable for a variety of cements with varying elemental compositions.

A construction composition comprises a) a cementitious binder comprising one or more calcium silicate mineral phases and one or more calcium aluminate mineral phases; b) optionally, an extraneous aluminate source; c) a sulfate source; d) an ettringite formation controller comprising (i) glyoxylic acid, a glyoxylic acid salt and/or a glyoxylic acid derivative; and (ii) at least one of a borate source and a carbonate source, wherein the carbonate source is selected from inorganic carbonates having an aqueous solubility of 0.1 g.Math.L.sup.−1 or more, organic carbonates, and mixtures thereof; and e) a polyol in an amount of 0.2 to 2.5 wt.-%, relative to the amount of cementitious binder a). The composition contains 0.05 to 0.2 mol of total available aluminate, calculated as Al(OH).sub.4.sup.−, from the calcium aluminate mineral phases plus the optional extraneous aluminate source, per 100 g of cementitious binder a); and the molar ratio of total available aluminate to sulfate is 0.4 to 2.0. The construction composition exhibits high early strength and sufficient open time. The advantageous effects are readily achievable for a variety of cements with varying elemental compositions.

Disclosed are product (e.g., board), slurry, and methods relating to an uncooked starch that can be used to enhance strength in one or more gypsum layers in the board. The uncooked starch has a hot water viscosity of from about 20 BU to about 300 BU according to the HWVA method, and/or a mid-range peak viscosity of from about 120 Brabender Units to about 1000 Brabender Units.