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  2. Flow table test - Wikipedia

    en.wikipedia.org/wiki/Flow_table_test

    The flow table test or slump-flow test is a method to determine consistency of fresh concrete. Flow table test is also used to identify transportable moisture limit of solid bulk cargoes. [ 1 ] It is used primarily for assessing concrete that is too fluid (workable) to be measured using the slump test , because the concrete will not retain its ...

  3. Calcium silicate hydrate - Wikipedia

    en.wikipedia.org/wiki/Calcium_silicate_hydrate

    When water is added to cement, each of the compounds undergoes hydration and contributes to the final state of the concrete. [2] 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.

  4. Cement chemist notation - Wikipedia

    en.wikipedia.org/wiki/Cement_chemist_notation

    Cement chemist notation (CCN) was developed to simplify the formulas cement chemists use on a daily basis. It is a shorthand way of writing the chemical formula of oxides of calcium , silicon , and various metals .

  5. AFm phases - Wikipedia

    en.wikipedia.org/wiki/AFm_phases

    So, AFm does not refer to a single pure mineralogical phase but rather to a mix of several AFm phases co-existing in hydrated cement paste (HCP). [ 1 ] Considering a monovalent anion X, the chemical formula can be rearranged and expressed as 2 [Ca 2 (Al,Fe)(OH) 6 ]·X·nH 2 O (or Ca 4 (Al,Fe) 2 (OH) 12 ·X·nH 2 O , as presented in the table in ...

  6. AFt phases - Wikipedia

    en.wikipedia.org/wiki/AFt_phases

    Calcium aluminates can form complex salts in combination with different types of anions.Two series of calcium aluminates are known in cement chemistry: AFm and AFt phases, being respectively mono- or tri-substituted with a given divalent anion X (e.g. SO 2− 4, CO 2− 3, or hosting a divalent impurity such as SeO 2− 4 [3]...), or with two units of a monovalent anion, e.g. OH −, Cl − ...

  7. Portland cement - Wikipedia

    en.wikipedia.org/wiki/Portland_cement

    Portland cement is the most common type of cement in general use around the world as a basic ingredient of concrete, mortar, stucco, and non-specialty grout. It was developed from other types of hydraulic lime in England in the early 19th century by Joseph Aspdin , and is usually made from limestone .

  8. Concrete - Wikipedia

    en.wikipedia.org/wiki/Concrete

    Separate paste mixing has shown that the mixing of cement and water into a paste before combining these materials with aggregates can increase the compressive strength of the resulting concrete. [69] The paste is generally mixed in a high-speed, shear-type mixer at a w/c (water to cement ratio) of 0.30 to 0.45 by mass. The cement paste premix ...

  9. Cement - Wikipedia

    en.wikipedia.org/wiki/Cement

    The concrete at young age must be protected against water evaporation due to direct insolation, elevated temperature, low relative humidity and wind. The interfacial transition zone (ITZ) is a region of the cement paste around the aggregate particles in concrete. In the zone, a gradual transition in the microstructural features occurs. [52]