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Superplasticizer
Superplasticizers (SPs), also known as high range water reducers, are Concrete additive, additives used for making high strength concrete or to place Self-consolidating concrete, self-compacting concrete. Plasticizers are chemical compounds enabling the production of concrete with approximately 15% less water content. Superplasticizers allow reduction in water content by 30% or more. These additives are employed at the level of a few weight percent. Plasticizers and superplasticizers also retard the setting and hardening of concrete. According to their Dispersant, dispersing functionality and action mode, one distinguishes two classes of superplasticizers: # Ionic bonding, Ionic interactions (electrostatic repulsion): lignosulfonates (first generation of ancient water reducers), Aromatic sulfonation, sulfonated synthetic polymers (naphthalene, or melamine, formaldehyde Condensation polymer, condensates) (second generation), and; # Steric effects: Polycarboxylates-ether (PCE) synt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Concrete Additive
Concrete is a composite material composed of aggregate bound together with a fluid cement that cures to a solid over time. It is the second-most-used substance (after water), the most–widely used building material, and the most-manufactured material in the world. When aggregate is mixed with dry Portland cement and water, the mixture forms a fluid slurry that can be poured and molded into shape. The cement reacts with the water through a process called hydration, which hardens it after several hours to form a solid matrix that binds the materials together into a durable stone-like material with various uses. This time allows concrete to not only be cast in forms, but also to have a variety of tooled processes performed. The hydration process is exothermic, which means that ambient temperature plays a significant role in how long it takes concrete to set. Often, additives (such as pozzolans or superplasticizers) are included in the mixture to improve the physical properties ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Concrete
Concrete is a composite material composed of aggregate bound together with a fluid cement that cures to a solid over time. It is the second-most-used substance (after water), the most–widely used building material, and the most-manufactured material in the world. When aggregate is mixed with dry Portland cement and water, the mixture forms a fluid slurry that can be poured and molded into shape. The cement reacts with the water through a process called hydration, which hardens it after several hours to form a solid matrix that binds the materials together into a durable stone-like material with various uses. This time allows concrete to not only be cast in forms, but also to have a variety of tooled processes performed. The hydration process is exothermic, which means that ambient temperature plays a significant role in how long it takes concrete to set. Often, additives (such as pozzolans or superplasticizers) are included in the mixture to improve the physical prop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plasticizer
A plasticizer ( UK: plasticiser) is a substance that is added to a material to make it softer and more flexible, to increase its plasticity, to decrease its viscosity, and/or to decrease friction during its handling in manufacture. Plasticizers are commonly added to polymers and plastics such as PVC, either to facilitate the handling of the raw material during fabrication, or to meet the demands of the end product's application. Plasticizers are especially key to the usability of polyvinyl chloride (PVC), the third most widely used plastic. In the absence of plasticizers, PVC is hard and brittle; with plasticizers, it is suitable for products such as vinyl siding, roofing, vinyl flooring, rain gutters, plumbing, and electric wire insulation/coating. Plasticizers are also often added to concrete formulations to make them more workable and fluid for pouring, thus allowing the water contents to be reduced. Similarly, they are often added to clays, stucco, solid rocket fuel, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polycarboxylate
Polycarboxylates are organic compounds with several carboxylic acid groups. Butane-1,2,3,4-tetracarboxylate is one example. Often, polycarboxylate refers to linear polymers with a high molecular mass (Mr ≤ 100 000) and with many carboxylate groups. They are Polyacrylic acid, polymers of acrylic acid or Copolymer, copolymers of acrylic acid and maleic acid. The polymer is used as the sodium salt (see: sodium polyacrylate). Use Polycarboxylates are used as Builder (detergent), builders in detergents. Their high chelating power, even at low concentrations, lowers soap scum, deposits on the laundry and inhibits the growth of calcite crystals. As applied to concrete, PCE-based Superplasticizer, superplasticizers can reduce water content by up to 40% at low dosages of around 0.12% to 0.22% without compromising fluidity. Polycarboxylate superplasticizers accelerate the early strength development of concrete and mortar. They also help with slump retention, ensuring concrete consis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rheology
Rheology (; ) is the study of the flow of matter, primarily in a fluid (liquid or gas) state but also as "soft solids" or solids under conditions in which they respond with plastic flow rather than deforming elastically in response to an applied forcRheology is the branch of physics that deals with the deformation and flow of materials, both solids and liquids.W. R. Schowalter (1978) Mechanics of Non-Newtonian Fluids Pergamon The term '' rheology'' was coined by Eugene C. Bingham, a professor at Lafayette College, in 1920 from a suggestion by a colleague, Markus Reiner.The Deborah Number The term was inspired by the aphorism of Heraclitus (often mistakenly attributed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Self-consolidating Concrete
Self-consolidating concrete or self-compacting concrete (SCC) National Ready Mixed Concrete Association is a mix which has a low , high deformability, good segregation resistance (prevents separation of particles in the mix), and moderate (necessary to ensure uniform suspension of solid particles during transportation, placement (without ext ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Water–cement Ratio
The water–cement ratio (w/c ratio, or water-to-cement ratio, sometimes also called the Water-Cement Factor, ) is the ratio of the mass of water () to the mass of cement () used in a concrete mix: :f = \frac = \frac The typical values of this ratio = are generally comprised in the interval 0.40 and 0.60. The water-cement ratio of the fresh concrete mix is one of the main, if not the most important, factors determining the quality and properties of hardened concrete, as it directly affects the concrete porosity, and a good concrete is always a concrete as compact and as dense as possible. A good concrete must be therefore prepared with as little water as possible, but with enough water to hydrate the cement minerals and to properly handle it. A lower ratio leads to higher strength and durability, but may make the mix more difficult to work with and form. Workability can be resolved with the use of plasticizers or super-plasticizers. A higher ratio gives a too fluid concrete m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dispersant
A dispersant or a dispersing agent is a substance, typically a surfactant, that is added to a suspension of solid or liquid particles in a liquid (such as a colloid or emulsion) to improve the separation of the particles and to prevent their settling or clumping. Dispersants are widely used to stabilize various industrial and artisanal products, such as paints, ferrofluids, and salad dressings. The plasticizers or superplasticizers, used to improve the workability of pastes like concrete and clay, are typically dispersants. The concept also largely overlaps with that of detergent, used to bring oily contamination into water suspension, and of emulsifier, used to create homogeneous mixtures of immiscible liquids like water and oil. Natural suspensions like milk and latex contain substances that act as dispersants. Applications Automotive Automotive engine oils contain both detergents and dispersants. Metallic-based detergents prevent the accumulation of varnish like deposits ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Self-consolidating Concrete
Self-consolidating concrete or self-compacting concrete (SCC) National Ready Mixed Concrete Association is a mix which has a low , high deformability, good segregation resistance (prevents separation of particles in the mix), and moderate (necessary to ensure uniform suspension of solid particles during transportation, placement (without ext ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Melamine
Melamine is an organic compound with the formula C3H6N6. This white solid is a trimer (chemistry), trimer of cyanamide, with a 1,3,5-Triazine, 1,3,5-triazine skeleton. Like cyanamide, it contains 66% nitrogen by mass, and its derivatives have fire retardant, fire-retardant properties due to its release of nitrogen gas when burned or charred. Melamine can be combined with formaldehyde and other agents to produce melamine resins. Such resins are characteristically durable thermosetting plastic used in high–pressure decorative laminates such as Formica (plastic), Formica, melamine dinnerware including cooking utensils, plates, and plastic products, laminate flooring, and dry erase boards. Melamine foam is used as insulation and soundproofing material, and in polymeric cleaning products such as Magic Eraser. Melamine-formaldehyde resin tableware was evaluated by the Taiwan Consumers' Foundation to have 20,000 parts per billion of free melamine that could migrate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
