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“The influence of pozzolanic materials on the mechanical stability of aluminous cement” by M. Collepardi, S. Morosi and P. Piccioli

✍ Scribed by John Bensted

Publisher: Elsevier Science
Year: 1996
Tongue: English
Weight: 157 KB
Volume: 26
Category: Article
ISSN: 0008-8846
DOI: 10.1016/0008-8846(96)00024-5

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✦ Synopsis

The experiments undertaken by Professor Collepardi and his colleagues(') have demonstrated that calcium aluminate (high alumina) cement containing condensed silica fume (csf) shows an increasing compressive stmngth trend at 20°C and 40°C for water/solids ratio 0.4, unlike the situation where pulverised fly ash (pfa) is present. This beneficial effect, particularly at 15% csf addition, is due to the high silica csf favouring the formation of gehlenite hydrate (strWngite) C.&SH, which appears to hinder transformation of the hexagonal calcium aluminate hydrates CAH,, and GAH, from converting to the denser cubic hydrate C&-J. The transformation is accompanied by increased porosity and compressive strength 10s~~'. For calcium aluminate cement with 15% replacement by csf, the strength decrease at 20°C and 40°C is almost completely reduced,

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