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. An inventive admixture combination which enables this unique design involves two different polycarboxylate comb polymers in combination with two specific viscosity modifying agents, and this combination provides highly workable concrete to be placed in a controlled, efficient manner.
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:
Disclosed is a waterproofing membrane that comprises a carrier sheet, a pressure sensitive adhesive layer on one surface of the carrier sheet, and a protective coating layer on the adhesive layer. The protective coating layer comprises polyvinyl acetate (PVAc). The protective coating layer protects the membrane against weather exposure, tolerates foot traffic and strongly adheres to concrete cast against it.
Abstract:
The present invention relates to modification of hydratable cement and cementitious materials, such as mortar cement and masonry or ready-mix concrete using ketone alcohol oil waste (“KAOW”) material, obtained as an alkali-soluble liquor waste byproduct at a certain stage in the commercial production of cyclohexanol and cyclohexanone. Preferred applications for KAOW are in chemical admixture formulations whereby KAOW is used to substitute for a portion of a cement dispersant such as sodium lignosulfonate, sodium gluconate, or other conventional dispersant. Another preferred use is in mortar cement and masonry concrete units such as blocks, pavers, curbstones, and other concrete masonry units wherein air void systems advantageously foster freeze-thaw durability.
Abstract:
The present invention pertains to the discovery that short chain aliphatic fatty acids, such as potassium sorbate, can be used in liquid-additive grinding compositions in the amount of at least 10%, more preferably at least 20%, and most preferably at least 30%, to mill carbonate materials into smaller particle size. The carbonate material can optionally be combined with another inorganic material in the grinding operation, such as limestone, lime, dolomites, talc, titanium dioxide, alumina, and kaolin, ceramics, and cement clinker. The use of the particularly described grinding additive composition are VOC-free and food-grade or food-contact approved, and are believed by the present inventors to resist the humectant behavior of the resultant ground particles which could inherently otherwise decrease efficiency of the particulate grinding process.
Abstract:
The present invention provides a wet press process and admixture components for making concrete slabs (flags) (16), curb (kerb) units, panels, boards, and other flat shapes, whereby colloidal silica and at least one alkanolamine and optional rheology control components are employed to provide an ideal combination of pressing time, green strength, surface definition, stack-ability, final concrete strength, and permeability. Stack-ability can be expressed in terms of minimum deflection or non-eccentricity of the units while standing on thickness edges at distances apart less than width or standing height. A wet press process typically involves introducing a highly fluid concrete mix into a mold (10,12), applying hydraulic pressure to consolidate the concrete (e.g., 1000-3000 PSI) and to extract excess water, removing the pressed concrete (16) while in a green state from the mold (10,12), and then standing the slab (16) units immediately upon removal from the mold (10,12) while in a green state, on an edge adjacent to but spaced apart from other edge-standing units. In further embodiments, rounded aggregates such as naturally occurring sand and/or gravel obtained from local sources can be incorporated into the concrete slabs without defeating (vertical) stack-ability in the green state.