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- If the page linked to in the ref is primarily informational about the general product, even as part of a website whose main purpose is to sell a particular product, it's ok. If the page is primarily about the specific brand, or exists more to sell than inform, the link should go. Argyriou (talk) 18:43, 6 February 2007 (UTC)
I don't think slag should be listed here. It's described by the theoreticians as a "latent hydraulic material" rather than a pozzolan: the action of lime on it is more in the nature of a catalyst than a reactant. The same goes for Hi-Calcium Class C Ash. . . .LinguisticDemographer 20:44, 18 May 2007 (UTC)
Pozzolanic reaction | main article |
Please, only edit the central page dealing with Pozzolanic reaction which has been transcluded in this page. See Wikipedia:Transclusion to learn how it works. Thank you. Shinkolobwe (talk) 13:30, 21 March 2009 (UTC)
The pozzolanic reaction is the chemical reaction that occurs in portland cement containing pozzolans. It is the main reaction involved in the Roman concrete invented in Ancient Rome and used to build, for example, the Pantheon.
At the basis of the pozzolanic reaction stands a simple acid-base reaction between calcium hydroxide, also known as Portlandite, or (Ca(OH)2), and silicic acid (H4SiO4, or Si(OH)4), and . Simply, this reaction can be schematically represented as follows:
- Ca(OH)2 + H4SiO4 → Ca2+ + H2SiO42- + 2 H2O → CaH2SiO4 · 2 H2O
or summarized in abbreviated notation of cement chemists:
- CH + SH → C-S-H
The product of general formula (CaH2SiO4 · 2 H2O ) formed is a calcium silicate hydrate, also abbreviated as C-S-H in cement chemist notation, the hyphenation denotes the variable stoichiometry. The ratio Ca/Si, or C/S, and the number of water molecules can vary and the above mentioned stoichiometry may differ.
Many pozzolans contain aluminate, or Al(OH)4-, that will react with calcium hydroxide and water to form calcium aluminate hydrates such as C4AH13, C3AH6 or hydrogarnet, or in combination with silica C2ASH8 or strätlingite (cement chemist notation). In the presence of anionic groups such as sulphate, carbonate or chlorine, AFm phases and AFt or ettringite phases can form.
- Aerated autoclaved concrete
- Alkali Silica Reaction
- Alkali-aggregate reaction
- Alkali-carbonate reaction
- Calcium silicate hydrate (CSH)
- Cement chemist notation
- Energetically modified cement (EMC)
- Fly ash
- Portland cement
- Rice husk ash
- Roman concrete
- Silica fume
- Sodium silicate
- Cook D.J. (1986) Natural pozzolanas. In: Swamy R.N., Editor (1986) Cement Replacement Materials, Surrey University Press, p. 200.
- Lechtman H. and Hobbs L. (1986) "Roman Concrete and the Roman Architectural Revolution", Ceramics and Civilization Volume 3: High Technology Ceramics: Past, Present, Future, edited by W.D. Kingery and published by the American Ceramics Society, 1986; and Vitruvius, Book II:v,1; Book V:xii2.
- McCann A.M. (1994) "The Roman Port of Cosa" (273 BC), Scientific American, Ancient Cities, pp. 92–99, by Anna Marguerite McCann. Covers, hydraulic concrete, of "Pozzolana mortar" and the 5 piers, of the Cosa harbor, the Lighthouse on pier 5, diagrams, and photographs. Height of Port city: 100 BC.
- Mertens, G.; R. Snellings, K. Van Balen, B. Bicer-Simsir, P. Verlooy, J. Elsen (2009). "Pozzolanic reactions of common natural zeolites with lime and parameters affecting their reactivity". Cement and Concrete Research 39 (3): 233–240. doi:10.1016/j.cemconres.2008.11.008. ISSN 0008-8846. Retrieved 2009-03-23.
GGBFS is NOT a pozzolan
I agree with comments above that GGFS is NOT a pozzolan. ASTM C441 / C441M is QUITE clear: "Standard Test Method for Effectiveness of Pozzolans or Ground Blast-Furnace Slag in Preventing Excessive Expansion of Concrete Due to the Alkali-Silica Reaction" [EMPHASIS ADDED]
It is a hydraulic binder.