A concrete mix, including: cementitious content between 25 and 200 kg/m.sup.3; fly ash content between 25 and 175 kg/m.sup.3; dirty sand with fine aggregates between 3% and 20%; water content between 150 I/m.sup.3 and 250 l/m.sup.3; and a chemical admixture comprising one or more components selected from the following: an acrylic, formaldehyde-free polymer-based admixture, modified in aqueous solution; a surfactant admixture configured to entrain micro air bubbles in concrete; and an organic polymer comprising hydrophilic groups for increasing the viscosity of the mixture.

Method and composition for producing aggregates from cement and concrete, including residual or returned concrete. Exemplary methods involve the use of an aggregate-forming inducer that provides a surface anchoring site for cement paste to bond/adhere, such as shredded news print, cardboard, or mixtures thereof, and also including fiber materials such as polymers, glass, and other material fibers. The aggregate-forming inducer is mixed with fresh concrete until aggregates are formed.

Method and composition for producing aggregates from cement and concrete, including residual or returned concrete. Exemplary methods involve the use of an aggregate-forming inducer that provides a surface anchoring site for cement paste to bond/adhere, such as shredded news print, cardboard, or mixtures thereof, and also including fiber materials such as polymers, glass, and other material fibers. The aggregate-forming inducer is mixed with fresh concrete until aggregates are formed.

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).

An additive, in particular a shrinkage reducing agent, for mineral binder compositions including at least one super absorbant polymer SAP and at least one defoamer D. Further, a mineral binder composition including the additive, processes and methods for the mixing thereof, and to hardened articles obtainable therefrom.

An additive, in particular a shrinkage reducing agent, for mineral binder compositions including at least one super absorbant polymer SAP and at least one defoamer D. Further, a mineral binder composition including the additive, processes and methods for the mixing thereof, and to hardened articles obtainable therefrom.

Disclosed herein are improved methods for recycling used engine oil (UEO). The method includes steps of, mixing UEO, a superplasticizer, and water to give a suspension; mixing aggregates, ordinary Portland cement (OPC), fly ash, silicate fume, and the water to give a first mixture; adding the suspension to the first mixture to give a second mixture; and molding and curing the second mixture into a concrete. The thus produced concrete contains up to 5% of UEO (by weight of total cementitious material) and exhibits comparable compressive properties as to that of ordinary concrete.

A cementitious composition including recycled superabsorbent polymer (RSAP) and a cementitious material. The RSAP has a purity level of at least 85 percent by weight of the RSAP. Also provided is a cementitious composition where the RSAP has substantially low levels of one or more residual drug entities. Also provided is a method for the construction of a self-sealing cement sheath, the method comprising: supplying a self-sealing slurry of a cementitious composition including cementitious material, an aqueous fluid, and RSAP into an underground geological formation, and allowing the self-sealing slurry of the cementitious composition to cure, thereby forming the self-sealing cement sheath. The RSAP is capable of swelling in the presence of fluid to seal any cracks formed in the self-sealing slurry during curing.

A cementitious composition including recycled superabsorbent polymer (RSAP) and a cementitious material. The RSAP has a purity level of at least 85 percent by weight of the RSAP. Also provided is a cementitious composition where the RSAP has substantially low levels of one or more residual drug entities. Also provided is a method for the construction of a self-sealing cement sheath, the method comprising: supplying a self-sealing slurry of a cementitious composition including cementitious material, an aqueous fluid, and RSAP into an underground geological formation, and allowing the self-sealing slurry of the cementitious composition to cure, thereby forming the self-sealing cement sheath. The RSAP is capable of swelling in the presence of fluid to seal any cracks formed in the self-sealing slurry during curing.

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).