Provided is a concrete composition, including: blast furnace slag; at least any one of expansive additive and cement; and water, wherein a unit water content of the water is 130 kg/m.sup.3 or less; wherein a content of the cement is 22% by mass or less relative to the blast furnace slag, and wherein a slump flow value of the concrete composition is 40 cm or greater.

The embodiments herein are directed to dry wall waste mixtures, formed under pressure into example embodiments referred to herein as dry wall waste blocks (DWBs) and/or gypsum wallboard waste blocks (GWWBs) and tile structures. DWBs/GWWBs mixtures in particular, often incorporate a higher percentage in the composite mixtures from about 60% up to 85% of dry wall waste than other mixtures and beneficially often incorporates substantially all of the wallboard facing paper as part of the composite mixture. That is, waste processing is simplified by comingling core and paper layers in the final product. DWBs/GWWBs mixtures utilize demolition and construction waste, replacing a high percentage of Portland cement with waste-derived binder.

Binders for geopolymers, which include: a) not less than 30 w % of a mixture of at least two chemically different aluminosilicates, b) not less than 20 w % of Ordinary Portland cement, and c) 8-20 w % of a mixture of calcium sulfoaluminate cement or calcium aluminate cement with a source of calcium sulfate, wherein in the mixture the weight ratio of calcium sulfate to calcium sulfoaluminate and/or calcium aluminate is between 0.08-1.5, preferably 0.3-1.1, more preferably 0.6-1.1. Also, geopolymers using such binders as well as their use in various construction methods.

The present invention provides exemplary method and additive for making cementitious binders that comprise primarily ground granulated blast furnace slag (GGBFS) having excellent strength at 24 hours, with preferably little or minimal amounts of Ordinary Portland Cement (OPC). As OPC manufacture involves carbon dioxide release into the atmosphere, the use of a GGBFS-based binder composition will help to enhance sustainability practices in the construction industry and minimizing strength losses implied by deletion of OPC. Strength in the GGBFS binder composition is enhanced by an alkaline-earth activator in combination with a strength enhancing component comprising dispersant and secondary activator.

Provided is a concrete composition, including: blast furnace slag; at least any one of expansive additive and cement; and water, wherein a unit water content of the water is 130 kg/m.sup.3 or less; wherein a content of the cement is 22% by mass or less relative to the blast furnace slag, and wherein a slump flow value of the concrete composition is 40 cm or greater.

The carbonate bonded, press-moulded article is produced by press-moulding a particulate, carbonatable material that contains water and by carbonating the obtained compact with carbon dioxide gas. In order to be able to ensure an optimal compressive strength of the article two types of tests are provided. In the first type of test a sample of the particulate material is compressed with an increasing compaction pressure and when water starts to be expelled from the material as from a particular compaction pressure, the press-moulding step is performed with a compaction pressure which is at least 7 MPa smaller than this compaction pressure. In the second type of test different samples of the particulate material are press-moulded with different compaction pressures and, after having released the compaction pressure, the density of the compact is determined. In case this density decreases instead of increases as from a particular compaction pressure, the press-moulding step is performed with a compaction pressure which is smaller than this particular compaction pressure.

The carbonate bonded, press-moulded article is produced by press-moulding a particulate, carbonatable material that contains water and by carbonating the obtained compact with carbon dioxide gas. In order to be able to ensure an optimal compressive strength of the article two types of tests are provided. In the first type of test a sample of the particulate material is compressed with an increasing compaction pressure and when water starts to be expelled from the material as from a particular compaction pressure, the press-moulding step is performed with a compaction pressure which is at least 7 MPa smaller than this compaction pressure. In the second type of test different samples of the particulate material are press-moulded with different compaction pressures and, after having released the compaction pressure, the density of the compact is determined. In case this density decreases instead of increases as from a particular compaction pressure, the press-moulding step is performed with a compaction pressure which is smaller than this particular compaction pressure.

The present subject-matter relates to landscaping product comprising steel slag and optionally cement, compositions and processes for preparing same.

The invention relates to a low-carbon-footprint hydraulic binder for mortar, and to mortar containing such a hydraulic binder. The hydraulic binder for mortar comprises at least 60% steel slag and at least one catalyst.

The invention relates to a low-carbon-footprint hydraulic binder for mortar, and to mortar containing such a hydraulic binder. The hydraulic binder for mortar comprises at least 60% steel slag and at least one catalyst.