Components Supplements
The properties of mineral supplements are strongly influenced by their grain structure, surface area and opreslyayuschy respectively reactivity or the ability to seal the concrete structure. Inert additives, such as ground quartz sand, at normal temperature does not react with the components of cement, however, under certain conditions, these additives may be reactivity (eg autoclaving). In most cases, inert additives are used to regulate the grain composition and the emptiness of the solid phase of concrete: aggregate – cement – mineral supplement, with a view to controlling the properties of concrete and mortar. Natural mineral supplements are fine comminution of various volcanic rocks (tuffs, ash, trace) or sedimentary Nogo (diatomite, tripoli, flask) origin. It is to the tuffs was originally applied the term 'pozzolana' under the name of an Italian village where it was mined.
Subsequently, the term spread to other active natural mineral supplements. MD volcanic or sedimentary origin composed mainly of silica and alumina (70 – 90%), which to some extent determine their pozzolan activity. These supplements have been widely used in the production of cement. These drawbacks include an increased water demand. Mineral supplements from man-made materials: fly ash, ground slag, microsilica, and others have different mineralogical composition and dispersion, which determine the effectiveness of their use in cement and concrete. TPP ash produced by burning pulverized coal in their mineral components, which contains clay substances, quartz and carbonate breed. Depending on the temperature of the furnace (1200 1600oS) and particle sizes of mineral coal or completely melts, or melts from the surface.
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