Abstract: 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.

Abstract: The present invention provides exemplary additive compositions and methods whereby hydratable cementitious compositions, such as concrete, can be modified using polycarboxylate type ether or ester cement dispersant polymers of a small size, in combination with at least one alkyl alkoxylate type surface active agent which typically hitherto is considered detergent-like in generating air bubbles (heads of foam) in aqueous environments. The present inventors discovered surprisingly that such agents could be used to control air content in plastic concrete mixes in combination with the polycarboxylate type ether or ester cement dispersant polymer.

Abstract: The present invention provides a liquid composition of quicklime particles within an alkylene glycol-based paste or slurry environment, which allows for pumpability and meterability of a liquid composition into cementitious materials such as concrete and mortar. Treated quicklime particles of the present invention manifest an unexpected and surprising hydration induction postponement behavior, as demonstrated through calorimetric testing.

Abstract: The present invention relates to very high workable yet controllable concrete mix design, admixture composition, and process for placing concrete. The mix design relates to particular aggregate/cement ratios and types which are characteristic of ready mix concrete (RMC), which provide high fluidity reminiscent of self-consolidating concrete (SCC), and which provides advantages over both RMC and SCC in terms of ease and speed in placement and finishability at the construction site placement zone, regardless of whether into a horizontal formwork (e.g., for slabs, floors) or into vertical formwork (e.g., for blocks, walls, columns, etc.), without loss of control and without generating high risks of segregation even when small amounts of water are added at the size to facilitate finishing of the concrete surface.

Abstract: 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.

Abstract: A method for manufacturing a concrete article is disclosed. The method comprises coating a mould or formwork with a release agent; spraying a mortar onto the mould or formwork, thereby forming a layer of mortar; casting concrete into the mould or formwork and onto the layer of mortar; and allowing the concrete to hydrate and harden in the mould or formwork, whereby a concrete article having a mortar skin layer is provided. The invention also provides concrete articles made by the described methods, and concrete structures which comprise the concrete articles. Concrete articles having the mortar skins can be made to have a relatively uniform outward appearance, even if the concrete cast behind the mortar skins may be different, in composition or appearance. Pigments or colorants and other expensive admixtures can be used in the mortar skin composition to greater visual effect, since the use of the mortar skin is less in overall volume compared to the concrete articles as a whole.

Abstract: The present invention provides a liquid composition of quicklime particles within an alkylene glycol-based paste or slurry environment, which allows for pumpability and meterability of a liquid composition into cementitious materials such as concrete and mortar. Treated quicklime particles of the present invention manifest an unexpected and surprising hydration induction postponement behavior, as demonstrated through calorimetric testing.

Abstract: The present invention provides an admixture composition comprising a liquid suspension of colloidal silica, siloxane, and polycarboxylate polymer cement dispersant for enhancing early age strength, finishability, and other properties in hydratable cementitious compositions such as concrete (e.g., shotcrete). An inventive method involves mixing the components together in a specific sequence, thereby to obtain a stable liquid suspension. This attainment of a stable liquid suspension is surprising and unexpected because (i) the polycarboxylate polymer cement dispersant and siloxane components are incompatible and immiscible with one another; and (ii) that colloidal silica and siloxane compound are incompatible and immiscible with one another.

Abstract: The present invention relates to very high workable yet controllable concrete mix design, admixture composition, and process for placing concrete. The mix design relates to particular aggregate/cement ratios and types which are characteristic of ready mix concrete (RMC), which provide high fluidity reminiscent of self-consolidating concrete (SCC), and which provides advantages over both RMC and SCC in terms of ease and speed in placement and finishability at the construction site placement zone, regardless of whether into a horizontal formwork (e.g., for slabs, floors) or into vertical formwork (e.g., for blocks, walls, columns, etc.), without loss of control and without generating high risks of segregation even when small amounts of water are added at the size to facilitate finishing of the concrete surface.

Abstract: The present invention provides an admixture composition comprising a liquid suspension of colloidal silica, siloxane, and polycarboxylate polymer cement dispersant for enhancing early age strength, finishability, and other properties in hydratable cementitious compositions such as concrete (e.g., shotcrete). An inventive method involves mixing the components together in a specific sequence, thereby to obtain a stable liquid suspension. This attainment of a stable liquid suspension is surprising and unexpected because (i) the polycarboxylate polymer cement dispersant and siloxane components are incompatible and immiscible with one another; and (ii) that colloidal silica and siloxane compound are incompatible and immiscible with one another.

Abstract: The present invention provides a composition and method for modifying a hydratable cementitious composition such as concrete or mortar using at least three different, distinct carboxylate polymers, even when clay is present in the concrete or mortar that would otherwise diminish dosage efficiency of polycarboxylate polymer used as dispersant. The three polycarboxylate polymers, designated as Polymer I, Polymer II, and Polymer II, are derived from monomer Components A, B, and C wherein Component A is an unsaturated carboxylic acid, Component B is a polyoxyalkylene, and Component C is an unsaturated carboxylate ester. The component molar ratio ranges for A:B:C are different as between Polymers I and II; while a distinct component molar ratio A:B+C is identified for Polymer III. When treated with these three different polycarboxylate polymers, the hydratable cementitious composition is surprisingly enhanced in terms of initial workability and slump retention, especially if clay is present.

Abstract: The present invention provides a composition and method for modifying a hydratable cementitious composition such as concrete or mortar using at least three different, distinct carboxylate polymers, even when clay is present in the concrete or mortar that would otherwise diminish dosage efficiency of polycarboxylate polymer used as dispersant. The three polycarboxylate polymers, designated as Polymer I, Polymer II, and Polymer II, are derived from monomer Components A, B, and C wherein Component A is an unsaturated carboxylic acid, Component B is a polyoxyalkylene, and Component C is an unsaturated carboxylate ester. The component molar ratio ranges for A:B:C are different as between Polymers I and II; while a distinct component molar ratio A:B+C is identified for Polymer III. When treated with these three different polycarboxylate polymers, the hydratable cementitious composition is surprisingly enhanced in terms of initial workability and slump retention, especially if clay is present.

Abstract: Non-fractured, non-fibrillatable short fibers, for reinforcing matrix materials such as concrete, have substantially uniform transverse cross-sectional areas along their length for maximum efficiency in pull-out resistance, and two different tapering characteristics along their lengths. Preferred bi-tapered fibers of the invention have a high modulus of elasticity in the range of 5-250 Gigapascal and are preferably modulated in both tapering dimensions. Matrix materials containing the fibers, as well as a method for making the fibers, are disclosed.

Abstract: Non-fractured, non-fibrillatable short fibers, for reinforcing matrix materials such as concrete, have substantially uniform transverse cross-sectional areas along their length for maximum efficiency in pull-out resistance, and two different tapering characteristics along their lengths. Preferred bi-tapered fibers of the invention have a high modulus of elasticity in the range of 5-250 Gigapascal and are preferably modulated in both tapering dimensions. Matrix materials containing the fibers, as well as a method for making the fibers, are disclosed.

Abstract: Non-fractured, non-fibrillatable short fibers, for reinforcing matrix materials such as concrete, have substantially uniform transverse cross-sectional areas along their length for maximum efficiency in pull-out resistance, and two different tapering characteristics along their lengths. Preferred bi-tapered fibers of the invention have a high modulus of elasticity in the range of 5-250 Gigapascal and are preferably modulated in both tapering dimensions. Matrix materials containing the fibers, as well as a method for making the fibers, are disclosed.

Abstract: Non-fractured, non-fibrillatable short fibers, for reinforcing matrix materials such as concrete, have substantially uniform transverse cross-sectional areas along their length for maximum efficiency in pull-out resistance, and two different tapering characteristics along their lengths. Preferred bi-tapered fibers of the invention have a high modulus of elasticity in the range of 5-250 Gigapascal and are preferably modulated in both tapering dimensions. Matrix materials containing the fibers, as well as a method for making the fibers, are disclosed.

Abstract: Synthetic polymer reinforcing fibers provide dispersability and strength in matrix materials such as concrete, masonry, shotcrete, and asphalt. The individual fiber bodies, substantially free of stress fractures and substantially non-fibrillatable, have generally quadrilateral cross-sectional profiles along their elongated lengths. Preferred fibers and matrix materials having such fibers demonstrate excellent finishability in addition to dispersion and toughness properties.

Abstract: The invention relates to fiber compositions that can be pumped and metered in the fashion of fluid chemical admixtures into a concrete mix, thereby enabling the fibers to be dispensed by concrete ready-mix plant operators who can provide verification of fiber administration and dosage. The fibers, particularly plastic shrinkage control fibers having large cumulative surface area, are suspended in an aqueous medium such that their surface area is already wetted out, thereby virtually assuring that substantial uniform fiber dispersion can be achieved without clumping and the delay that is usually required by fiber intermixing.

Abstract: The invention relates to fiber compositions that can be pumped and metered in the fashion of fluid chemical admixtures into a concrete mix, thereby enabling the fibers to be dispensed by concrete ready-mix plant operators who can provide verification of fiber administration and dosage. The fibers, particularly plastic shrinkage control fibers having large cumulative surface area, are suspended in an aqueous or non-aqueous medium such that their surface area is already wetted out, thereby virtually assuring that substantial uniform fiber dispersion can be achieved without clumping and the delay that is usually required by fiber intermixing.

Abstract: Exemplary mechanically-flattened fibers of the invention comprise generally elongate bodies having varied width or thickness dimensions and micro-diastrophic surface deformities. Preferred fibers are elongate synthetic polymer or multipolymer blend fibers for reinforcing matrix materials such as concrete, shotcrete, gypsum-containing materials, asphalt, plastic, rubber, and other matrix materials. Preferred methods for manufacturing such fibers comprise subjecting synthetic polymer fibers to compressive forces sufficient to achieve flattening and surface micro-diastrophism without substantially shredding and abrading the fibers. Further exemplary fibers and methods involve mechanically-flattening intertwined or braided fibers or fiber bundles, thereby providing fibers having physical impressions thereon of the intertwinement or braidingand, optionally though preferably of micro-diastrophic surface deformities.