Abstract:
The present invention relates to a process to improve the mechanical strength 28 days after mixing of a hydraulic composition submitted to a thermal treatment, the hydraulic composition comprising a hydraulic binder and optionally a mineral addition, wherein the process comprises the addition of a calcium salt and an optimized quantity of sulphate to the hydraulic composition.
Abstract:
The invention provides a cementitious composition comprising a cement component comprising (i) an accelerant, (ii) a calcium sulphate source and (iii) an ettringite forming cement; an aggregate; and optionally water; wherein the cement has a minimum unconfined compressive strength of 1500 psi when tested in accordance with ASTM C1140 and/or C1604 at 15 minutes after placement; methods for its use and concrete formed from it.
Abstract:
The present invention provides a composition and method involving the use of at least one cement dispersant mixed with a diphosphonic or triphosphonic acid or salt as a slump retention-enhancing agent that is chemically unreacted with the at least one cement dispersant, such that, when introduced into the aqueous environment of a cementitious mixture, slump retention-enhancing agent molecules move independently of cement dispersant molecules with respect to the cement particles.
Abstract:
The invention relates to a method for the manufacture of concrete with a high early strength, to concrete with a high early strength and to application of concrete with a high early strength. The method is characterized in that for the manufacture of the concrete, which involves the mixing of a bonding agent, gravel, a composition of aggregates and water, not one aggregate, but two different aggregates are used. More preferably, the two aggregates are limestone flour and pumice stone, with between 30 and 50 weight percent of the total weight of pumice stone and limestone flour being made up of pumice stone and 50 to 70 weight percent of limestone flour.
Abstract in simplified Chinese:一种用于预铸水硬性水泥之高度 初期强度掺合物,其包含钙盐及一种具有含碳主干之共聚物,于该主干上系连接水泥锚定成员,如羧基,及其亦藉选自包括酰胺与酰亚胺成员之链结连接氧化烯悬垂基。所使用之共聚物较佳为借由反应丙烯酸系聚合物与氨或烷氧化胺而形成。该钙盐,较佳为亚硝酸钙,与该共聚物可以一种掺合物同时加入,或个别加入。本发明亦大致关于在混凝土、水泥、砖、与灰泥混合物,及特别是对预铸混凝土之高度增强初期强度之方法,及亦有关此种含钙盐与共聚物之水硬性混合物。
Abstract:
PROBLEM TO BE SOLVED: To provide a high-early-strength agent for hydraulic composition with excellent improved effect of short-term strength. SOLUTION: The high-early-strength agent for hydraulic composition is composed of a compound (a) which is obtained by reacting (A) one or more substances selected from polyhydric alcohols having functionality of 3-20 and alkylene oxide addition products of polyhydric alcohols having functionality of 3-20 with (B) a sulfating agent. An additive composition for hydraulic composition containing the compound (a) is also disclosed. COPYRIGHT: (C)2010,JPO&INPIT
Abstract:
PROBLEM TO BE SOLVED: To provide a concrete composition for centrifugal casting developing high strength in centrifugally casted concrete secondary products such as a pile, a pole, a Hume pipe and the like. SOLUTION: The concrete composition for centrifugal casting developing high strength contains high-early strength portland cement, a high strength admixture, a dispersant, an aggregate and water and is characterized by that the content of hemihydrate gypsum in the high-early strength portland cement is 20-80 mass%, the high strength admixture contains anhydrous gypsum and amorphous silica, the mass ratio of anhydrous gypsum to amorphous silica in the high strength admixture is 15/85-80/20 and the dispersant is a polycarboxylic acid-based dispersant. COPYRIGHT: (C)2008,JPO&INPIT