Search results
Results From The WOW.Com Content Network
Only calcium silicates contribute to the strength. Tricalcium silicate is responsible for most of the early strength (first 7 days). [3] Dicalcium silicate, which reacts more slowly, only contributes to late strength. Calcium silicate hydrate (also shown as C-S-H) is a result of the reaction between the silicate phases of Portland cement and water.
Calcium silicate, also known as slag, is produced when molten iron is made from iron ore, silicon dioxide and calcium carbonate in a blast furnace. When this material is processed into a highly refined, re-purposed calcium silicate aggregate, it is used in the remediation of acid mine drainage (AMD) on active and passive mine sites. [ 13 ]
Tobermorite is a calcium silicate hydrate mineral with chemical formula: Ca 5 Si 6 O 16 (OH) 2 ·4H 2 O or Ca 5 Si 6 (O,OH) 18 ·5H 2 O. Two structural varieties are distinguished: tobermorite-11 Å and tobermorite-14 Å. Tobermorite occurs in hydrated cement paste and can be found in nature as an alteration mineral in metamorphosed limestone ...
The hydrate is referred to as the calcium silicate hydrate – "C-S-H-" – phase. It grows as a mass of interlocking needles that provide the strength of the hydrated cement system. High alite reactivity is desirable in Portland cement manufacture, and this is achieved by retaining, as far as possible, high temperature polymorphs, in crystals ...
Calcium silicate hydrate: C-A-H: Phase more complex than C-S-H: Calcium aluminate hydrate C-A-S-H: This is even more complex than C-S-H and C-A-H: Calcium aluminate silicate hydrate AFt: C 6 A S 3 H 32, sometimes with substitution of Fe for Al, and/or CO 2− 3 for SO 2− 4: Calcium trisulfoaluminate hydrate, or ettringite: AFm
The tables below provides information on the variation of solubility of different substances (mostly inorganic compounds) in water with temperature, at one atmosphere pressure.
The following chart shows the solubility of various ionic compounds in water at 1 atm pressure and room temperature (approx. 25 °C, 298.15 K). "Soluble" means the ionic compound doesn't precipitate, while "slightly soluble" and "insoluble" mean that a solid will precipitate; "slightly soluble" compounds like calcium sulfate may require heat to precipitate.
Thaumasite is a calcium silicate mineral, containing Si atoms in unusual octahedral configuration, with chemical formula Ca 3 Si(OH) 6 (C O 3)(SO 4)·12H 2 O, also sometimes more simply written as CaSiO 3 ·CaCO 3 ·CaSO 4 ·15H 2 O. It occurs as colorless to white prismatic hexagonal crystals, typically as acicular radiating groups. It also ...