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The phase composition of a particular cement can be quantified through a complex set of calculation known as the Bogue formula. To avoid the flash setting of concrete, due to the very fast hydration of the tricalcium aluminate (C 3 A), 2–5 wt. % calcium sulfate is interground with the cement clinker to prepare the cement powder.
Chert (/ tʃ ɜːr t /) is a hard, fine-grained sedimentary rock composed of microcrystalline or cryptocrystalline quartz, [1] the mineral form of silicon dioxide (SiO 2). [2] Chert is characteristically of biological origin, but may also occur inorganically as a chemical precipitate or a diagenetic replacement, as in petrified wood.
Instead of using a 'nominal mix' of 1 part cement, 2 parts sand, and 4 parts aggregate, a civil engineer will custom-design a concrete mix to exactly meet the requirements of the site and conditions, setting material ratios and often designing an admixture package to fine-tune the properties or increase the performance envelope of the mix ...
Portland cement blends are often available as inter-ground mixtures from cement producers, but similar formulations are often also mixed from the ground components at the concrete mixing plant. Portland blast-furnace slag cement , or blast furnace cement (ASTM C595 and EN 197-1 nomenclature respectively), contains up to 95% ground granulated ...
The ultimate strength of concrete is influenced by the water-cementitious ratio (w/cm), the design constituents, and the mixing, placement and curing methods employed.All things being equal, concrete with a lower water-cement (cementitious) ratio makes a stronger concrete than that with a higher ratio. [2]
Diagenesis – Physico-chemical changes in sediments occurring after their deposition; Dinocochlea – Trace fossil in the Natural History Museum, London; Dorodango – Japanese art form in which earth and water are molded to create a delicate shiny sphere; Gypcrust – Hardened layer of soil with a high percentage of gypsum.
The volume of such a mixture is slightly less than the sum of the volumes of the components. Thus, by the above definition, the term "40% alcohol by volume" refers to a mixture of 40 volume units of ethanol with enough water to make a final volume of 100 units, rather than a mixture of 40 units of ethanol with 60 units of water.
In concrete chemistry, ettringite is a hexacalcium aluminate trisulfate hydrate, of general formula 6CaO·Al 2 O 3 ·3SO 3 ·32H 2 O, or 3CaO·Al 2 O 3 ·3CaSO 4 ·32H 2 O, also abbreviated as C 6 A S 3 H 32 in cement chemist notation. Ettringite is formed in the hydrated Portland cement system as a result of the reaction of tricalcium aluminate (C