Detail publikace

Some Issues of Shrinkage-Reducing Admixtures Application in Alkali-Activated Slag Systems

BÍLEK, V. KALINA, L. NOVOTNÝ, R. TKACZ, J. PAŘÍZEK, L.

Originální název

Some Issues of Shrinkage-Reducing Admixtures Application in Alkali-Activated Slag Systems

Typ

článek v časopise ve Web of Science, Jimp

Jazyk

angličtina

Originální abstrakt

Significant drying shrinkage is one of the main limitations for the wider utilization of alkali-activated slag (AAS). Few previous works revealed that it is possible to reduce AAS drying shrinkage by the use of shrinkage-reducing admixtures (SRAs). However, these studies were mainly focused on SRA based on polypropylene glycol, while as it is shown in this paper, the behavior of SRA based on 2-methyl-2,4-pentanediol can be significantly different. While 0.25% and 0.50% had only a minor effect on the AAS properties, 1.0% of this SRA reduced the drying shrinkage of waterglass-activated slag mortar by more than 80%, but it greatly reduced early strengths simultaneously. This feature was further studied by isothermal calorimetry, mercury intrusion porosimetry (MIP) and scanning electron microscopy (SEM). Calorimetric experiments showed that 1% of SRA modified the second peak of the pre-induction period and delayed the maximum of the main hydration peak by several days, which corresponds well with observed strength development as well as with the MIP and SEM results. These observations proved the certain incompatibility of SRA with the studied AAS system, because the drying shrinkage reduction was induced by the strong retardation of hydration, resulting in a coarsening of the pore structure rather than the proper function of the SRA.

Klíčová slova

alkali activated slag; shrinkage reducing admixture; shrinkage; hydration; microstructure; retardation

Autoři

BÍLEK, V.; KALINA, L.; NOVOTNÝ, R.; TKACZ, J.; PAŘÍZEK, L.

Vydáno

10. 6. 2016

Nakladatel

MDPI

ISSN

1996-1944

Periodikum

Materials

Ročník

9

Číslo

6

Stát

Švýcarská konfederace

Strany od

1

Strany do

12

Strany počet

12

URL

http://www.mdpi.com/1996-1944/9/6/462

Plný text v Digitální knihovně

http://hdl.handle.net/11012/61755

BibTex

@article{BUT125827,
  author="Vlastimil {Bílek} and Lukáš {Kalina} and Radoslav {Novotný} and Jakub {Tkacz} and Ladislav {Pařízek}",
  title="Some Issues of Shrinkage-Reducing Admixtures Application in Alkali-Activated Slag Systems",
  journal="Materials",
  year="2016",
  volume="9",
  number="6",
  pages="1--12",
  doi="10.3390/ma9060462",
  issn="1996-1944",
  url="http://www.mdpi.com/1996-1944/9/6/462"
}