Abstracts Book - IMRC 2018

• SE2-O019
MICROSTRUCTURAL EVOLUTION OF BLAST FURNACE SLAG
CEMENTS ACTIVATED WITH BINARY ALKALINE SOLUTIONS
Irma Elizabeth Betancourt Castillo 1 , Oswaldo Burciaga Díaz 1 , José Alonso Díaz Guillén 1
1 Instituto Tecnológico de Saltillo, División de Estudios de Posgrado e Investigación, Mexico.
The mechanical properties and microstructural evolution of Na 2 CO 3 -NaOH
activated blast furnace slag pastes were studied as a function of the curing time
and temperature. Pastes were prepared and cured at 20 °C and 60°C-24h-20°C
in isothermal chambers for up 90 days. The results indicated that the
combination of Na 2 CO 3 -NaOH has a positive effect to produce alternative
cements with environmental advantages in relation to Portland cement based
materials. Samples cured at 20 °C developed 64 MPa at 90 days, and those at
60°C-24h-20°C had rapid strength gain at early ages but strengths of ~53 MPa
at 90 days were observed. The researched binders were studied by X-Ray
Diffraction (XRD), Scanning Electron Microscopy (SEM), Thermal Analysis, and
Nuclear Magnetic Resonance (NMR) observing that the reaction products are C-
(A)-S-H type gels and hydrotalcite like phases; carbonated phases were not
observed as previously reported for similar compositions.
Acknowledgment:
I. Betancourt Castillo thanks CONACYT by the scholarship for the Master degree
studies and also to the Tecnological National of Mexico by the financial support.
Keywords: alkali-activated materials, blast furnace slag, microstructural evolution
Presenting authors email: ielizabeth@itsaltillo.edu.mx