Nanotechnology offers an opportunity to modify and observe cement at the nanolevel. In this research, the degree of dispersion of two aqueous suspensions of organomodified montmorillonite (OMMT) clay nanoparticles and one inorganic nanoclay (nC) dispersion was verified by TEM. The effect of the addition of each one of the three dispersions to a high limestone content (40 % by mass of binder) Portland limestone cement was investigated in terms of compressive strength, thermogravimetric (TG) analyses and morphological characteristics of the pastes. It was found that the upper limit of nC addition, in such pastes is 1 % nC solids by mass of binder and that intercalated OMMT cannot offer significant compressive strength improvement. However, there were strong indications that the pozzolanic reactions were promoted by the better dispersed OMMT and by the inorganic nC dispersion. The FESEM images captured, depicted the morphological characteristics of the nanomodified cement formulations. Furthermore, evidences suggest that the specific nanoclays can offer enhancement for flexural performance of blended cements with no degradation over time. Overall, the inorganic nC dispersion exhibited the highest pozzolanic activity, the highest flexural strength improvement and the most dense microstructure. The research reported was part of a much broader research project (FIBCEM) supported by the EU.
|Title of host publication||Nanotechnology in Construction|
|Subtitle of host publication||Proceedings of NICOM5|
|Editors||Konstantin Sobolev, Surendra P Shah|
|Publication status||Published - 2015|