J. Lombardi et al., EXPERIMENTAL-MEASUREMENT OF THE KINETICS OF FORMATION OF A SILICON-CALCIUM GEL PRODUCED BY AN ALKALI-SILICA REACTION, Cement and concrete research, 27(9), 1997, pp. 1379-1391
Citations number
15
Categorie Soggetti
Construcion & Building Technology","Material Science
The alkali-silica reaction (ASR) is an internal physical and chemical
process that appears to be the cause of functional disorders observed
in concrete structures. These disorders are attributable to the growth
, in the limited porous space of concrete, of gels produced by those A
SR. So the kinetics of formation of gel produced by the ASR is followe
d by indirect method using the properties of silicate gels to exchange
ions. The ASR properly so called is done under a closed system by mak
ing an alkaline dissolution upon an opal in the presence of an excess
of calcium hydroxide Ca(OH)(2), and an exchangeable cation, the stront
ium. The main results are: The quantity of formed gel as a function of
time corresponds with a kinetics of formation of gel constant and ver
y quick under the experimental conditions chosen (25 and 38 degrees C)
. The experimental results, at both temperatures, suit with the thermo
dynamic approach used. (C) 1997 Elsevier Science Ltd.