A concrete composition having an optimized formulation and suitable for 3-D printing is provided. The composition may include a hydraulic cement composition, aggregate, cement and/or aggregate by-product dust, one or more rheology modifiers, a plasticizer, fibers, and a sufficient amount of water to effect setting of the composition. Optionally the concrete composition may include a setting agent. A method for 3D printing multiple layers of the concrete composition is also provided.

A method includes adding an acidic salt of Iron (III) as additive to cement, mortar or concrete.

A method includes adding an acidic salt of Iron (III) as additive to cement, mortar or concrete.

A two-component inorganic injection mortar system includes a curable aqueous-phase aluminous cement component A and an initiator component B in aqueous-phase for initiating the curing process. Component A includes at least one blocking agent which is phosphoric acid, metaphosphoric acid, phosphorous acid or phosphonic acid, at least one plasticizer and water. Component B includes an initiator, at least one retarder, at least one mineral filler and water. The curable aqueous-phase aluminous cement component A includes calcium aluminate cement having an average particle size in the range of from 0.5 to 15 μm. A two-component system, which is ready-for-use, can be used for chemical fastening of anchors, such as metal elements, or in mineral substrates, such as structures made of brickwork, concrete, pervious concrete or natural stone.

A two-component inorganic injection mortar system includes a curable aqueous-phase aluminous cement component A and an initiator component B in aqueous-phase for initiating the curing process. Component A includes at least one blocking agent which is phosphoric acid, metaphosphoric acid, phosphorous acid or phosphonic acid, at least one plasticizer and water. Component B includes an initiator, at least one retarder, at least one mineral filler and water. The curable aqueous-phase aluminous cement component A includes calcium aluminate cement having an average particle size in the range of from 0.5 to 15 μm. A two-component system, which is ready-for-use, can be used for chemical fastening of anchors, such as metal elements, or in mineral substrates, such as structures made of brickwork, concrete, pervious concrete or natural stone.

A method of producing a carbonated composite material includes: providing a carbonatable cementitious material in particulate form; mixing the carbonatable cementitious material with water to produce a mix; forming a predetermined shape with the mix, wherein the predetermined shape has an initial pore structure containing an initial pore solution having a first pH; pre-conditioning the predetermined shape to remove a predetermined amount of the water from the predetermined shape to produce a pre-conditioned shape; carbonating the pre-conditioned shape in an environment comprising carbon dioxide to produce a modified pore structure containing a modified pore solution having and a second pH, wherein the difference between the first pH and the second pH is represented by a ΔpH, and the ΔpH is 1.0 or less.

A method of producing a carbonated composite material includes: providing a carbonatable cementitious material in particulate form; mixing the carbonatable cementitious material with water to produce a mix; forming a predetermined shape with the mix, wherein the predetermined shape has an initial pore structure containing an initial pore solution having a first pH; pre-conditioning the predetermined shape to remove a predetermined amount of the water from the predetermined shape to produce a pre-conditioned shape; carbonating the pre-conditioned shape in an environment comprising carbon dioxide to produce a modified pore structure containing a modified pore solution having and a second pH, wherein the difference between the first pH and the second pH is represented by a ΔpH, and the ΔpH is 1.0 or less.

A concrete composition and method include a portion of fine aggregate bearing a coating of a polymer or an admixture, which may be a continuous coating layer or a layer of powdered, discrete particles embedded in a binder. The polymeric coating may be an admixture in powdered form, a super absorbent polymer (insoluble in water, but absorbing water), or another polymer such as the acrylamides, co-polymers thereof, polyacrylamides, or the like (soluble in water). The coating absorbs water, but particles are too small to form significant voids. Water is absorbed into the concrete mix in far greater proportions (e.g. w/c ratio over 0.5) improving workability, doubling workability time, and improving ultimate compressive stress (strength).

A concrete composition and method include a portion of fine aggregate bearing a coating of a polymer or an admixture, which may be a continuous coating layer or a layer of powdered, discrete particles embedded in a binder. The polymeric coating may be an admixture in powdered form, a super absorbent polymer (insoluble in water, but absorbing water), or another polymer such as the acrylamides, co-polymers thereof, polyacrylamides, or the like (soluble in water). The coating absorbs water, but particles are too small to form significant voids. Water is absorbed into the concrete mix in far greater proportions (e.g. w/c ratio over 0.5) improving workability, doubling workability time, and improving ultimate compressive stress (strength).

The present disclosure relates to a medical cement composition containing calcium silicate in an amount of less than 20 wt % of a total weight of the composition, with a lithium salt being added thereto. The medical cement composition of the present disclosure has a low compressive strength of 12 MPa or less, after being hardened, for easy removal, excellent stability in storage, and high bioactivity.