Civil Engineering Reference
In-Depth Information
CaO
SiO
4
(a)
CaO
SiO
4
(b)
17.3
Structural model proposed for a C-S-H gel with a dreirketten-
type chain.
ratified by Fernández-Jiménez (2000). Based on
29
Si and
27
al magic angle
spinning nuclear magnetic resonance (maS nmr) studies (Fernández-Jiménez;
2000; Fernández-Jiménez et al.,
2003; Fernández-Jiménez and Palomo,
2010;
Puertas et al.,
2011), the author showed that the presence of al gives rise to
gels with longer linear chains as well as to the possible existence of sporadic
inter-chain, Si—o—al bonds and consequently two-dimensional structures
(Q
3
(nal) structures). Under those conditions, the c-S-H gels would become
c-(a)-S-H gels (see Fig. 17.4(b)).
