This invention relates to a solidifying agent for solidifying radioactive waste, and more particularly to a solidifying-agent composition for solidifying radioactive waste, including alumina cement and a gypsum powder. The solidifying-agent composition including alumina cement and a gypsum powder is capable of effectively minimizing an increase in the volume of a solidified radioactive waste product to a level satisfying physical and chemical safety regulations upon the solidification of radioactive waste.

A sheet 100 of water-soluble material such as polyvinyl alcohol comprises a plurality of individual, sealed pockets 110, each containing concrete admixture. The sheet is cut to size and attached to the interior of a formwork structure 200 with, for example, PVA glue. After concrete is poured into the formwork, covering the sheet 100, the sheet dissolves, releasing the admixture onto the surface of the concrete as it sets. In another arrangement, a sealed container 300 formed from a water-soluble material contains concrete admixture. The external wall of the container has a plurality of regions 320 where a thickness of the wall is reduced. The container is attached to interior walls of a formwork structure 200 or to reinforcing bars inside a formwork structure. After concrete is poured into the formwork, submerging the container, the container dissolves, with the thinner regions dissolving sooner, releasing the admixture into the concrete.

A sheet 100 of water-soluble material such as polyvinyl alcohol comprises a plurality of individual, sealed pockets 110, each containing concrete admixture. The sheet is cut to size and attached to the interior of a formwork structure 200 with, for example, PVA glue. After concrete is poured into the formwork, covering the sheet 100, the sheet dissolves, releasing the admixture onto the surface of the concrete as it sets. In another arrangement, a sealed container 300 formed from a water-soluble material contains concrete admixture. The external wall of the container has a plurality of regions 320 where a thickness of the wall is reduced. The container is attached to interior walls of a formwork structure 200 or to reinforcing bars inside a formwork structure. After concrete is poured into the formwork, submerging the container, the container dissolves, with the thinner regions dissolving sooner, releasing the admixture into the concrete.

Disclosed are a mixed shrinkage reducing agent for concrete and a preparation method thereof. The mixed shrinkage reducing agent for concrete includes the following components in parts by weight: 35-45 of alkali modified diatomite, 15-22 of magnesium oxide, 13-20 of vermiculite, 8-11 of borax, 3-9 of sodium hexametaphosphate, and 7-13 of citric acid modified starch. The mixed shrinkage reducing agent for concrete according to the present application is used as an admixture to be mixed into cement for preparing concrete.

Disclosed are a mixed shrinkage reducing agent for concrete and a preparation method thereof. The mixed shrinkage reducing agent for concrete includes the following components in parts by weight: 35-45 of alkali modified diatomite, 15-22 of magnesium oxide, 13-20 of vermiculite, 8-11 of borax, 3-9 of sodium hexametaphosphate, and 7-13 of citric acid modified starch. The mixed shrinkage reducing agent for concrete according to the present application is used as an admixture to be mixed into cement for preparing concrete.

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).

A composite structural material formed from aggregate within a matrix, the aggregate being a particulate material where each particle includes at least three radial legs extending outwardly from a central hub.

A composite structural material formed from aggregate within a matrix, the aggregate being a particulate material where each particle includes at least three radial legs extending outwardly from a central hub.

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).