Title:
Properties of Ternary Cement Pastes with Nanosilica and Rice Husk Ash
Author(s):
Daniel da Silva Andrade, João Henrique da Silva Rêgo, Moisés Frías Rojas, Paulo Cesar Morais, Maria José de Souza Serafim, and Anne Neiry Lopes
Publication:
Materials Journal
Volume:
117
Issue:
1
Appears on pages(s):
233-242
Keywords:
nanosilica; portland cement; rice husk ash; silica fume; synergistic effec
DOI:
10.14359/51720291
Date:
1/1/2020
Abstract:
The present study reports on the pioneering addition of rice husk ash (RHA) and silica fume (SF) into portland cement-based (PC-based) materials, combined with nanosilica (NS), aiming to assess the impact of the RHA on the mechanical and microstructure properties of ternary mixtures. Pastes were prepared to perform compressive strength tests, thermal analysis (DTA/TG), infrared spectroscopy, and mercury porosimetry. The highest reduction in the calcium hydroxide index (CH.I) and the highest calciumsilicate-
hydrate (C-S-H) formation are found in the PC-based ternary mixture containing NS plus SF and NS plus RHA after 91 days of hydration. In line with the aforementioned trends, the ternary mixtures containing NS show the highest compressive strength values and reduction of mean diameter of porous. Indeed, we found strong evidence of synergistic effect in ternary mixtures incorporating NS plus RHA or SF, thus supporting their use in fabrication of cementitious materials.