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Portland cement is the most common type of cement in ... clinker phases and other compounds. ... common cement that comprise portland cement as a main constituent ...
Calcium silicate hydrate (also shown as C-S-H) is a result of the reaction between the silicate phases of Portland cement and water. This reaction typically is expressed as: 2 Ca 3 SiO 5 + 7 H 2 O → 3 CaO · 2 SiO 2 · 4 H 2 O + 3 Ca(OH) 2 + 173.6 kJ. also written in cement chemist notation, (CCN) as: 2 C 3 S + 7 H → C 3 S 2 H 4 + 3 CH + heat
The resulting hard substance, called 'clinker', is then ground with a small amount of gypsum (CaSO 4 ·2H 2 O) into a powder to make ordinary Portland cement, the most commonly used type of cement (often referred to as OPC). Portland cement is a basic ingredient of concrete, mortar, and most non-specialty grout. The most common use for Portland ...
Portland cement clinker (abbreviated k in the European norms) is ground to a fine powder and used as the binder in many cement products. A small amount of gypsum (less than 5 wt.%) must be added to avoid the flash setting of the tricalcium aluminate (Ca 3 Al 2 O 6 ), the most reactive mineral phase (exothermic hydration reaction) in Portland ...
The four compounds referred as C 3 S, C 2 S, C 3 A and C 4 AF are known as the main crystalline phases of Portland cement. The phase composition of a particular cement can be quantified through a complex set of calculation known as the Bogue formula.
Portland cement is the most common type of cement in general usage. It is a basic ingredient of concrete, mortar, and many plasters. [43] It consists of a mixture of calcium silicates (alite, belite), aluminates and ferrites—compounds, which will react with water.
Belite is the mineral in Portland cement responsible for development of "late" strength. The other silicate, alite contributes "early" strength, due to its higher reactivity. Belite reacts with water (roughly) to form calcium silicate hydrates (C-S-H) and portlandite (Ca(OH) 2) according to the reaction:
The main phases are the calcium silicate hydrates (C-S-H) (the "glue" in cement paste), calcium sulfo-aluminate phases (AFm and AFt, ettringite) and hydrogarnet. C-S-H phases are less soluble (~ 10 −5 M) than portlandite (CH) (~ 2.2 10 −2 M at 25 °C) and therefore are expected to play a negligible role for the calcium ions release.