The effect of additional aluminium to the strength of geopolymer paste

Aulia Rahman, Januarti Jaya Ekaputri

Research output: Contribution to journalConference articlepeer-review

1 Scopus citations


Alternative cementitious materials have been widely used because of the environmental issue of greenhouse gasses produced by portland cement production. A possible solution is the green concrete made from fly ash based-geopolymer paste. The natural differences of Indonesian coal ash lead to various chemical contents of fly ash. The chemical composition of alkali activated paste is also varied causing differences in the strength of the paste. Silica to alumina ratio is indicated as the greatest influencing factor to geopolymer strength. The bond among silica-alumina preserves a compact microstructure resulting in the strength. This paper proposes a Si-Al ratio between 1.5 and 2.0 by adding a synthetic aluminium substance from some sources. Using a natural aluminium substance from other fly ashes which contain excessive amounts of Al2O3 was one of that efforts. The result indicated that the addition of a small amount of aluminium powder showed insignificant differences in geopolymer strength. The powder addition of up to 4% of fly ash decreased the strength by up to 60% of the original one. The methods of mixing are indicated as the trigger of lower strength because.

Original languageEnglish (US)
Article number01011
JournalMATEC Web of Conferences
StatePublished - Aug 22 2018
Event4th International Conference on Rehabilitation and Maintenance in Civil Engineering, ICRMCE 2018 - Solo Baru, Indonesia
Duration: Jul 11 2018Jul 12 2018

All Science Journal Classification (ASJC) codes

  • General Chemistry
  • General Materials Science
  • General Engineering


Dive into the research topics of 'The effect of additional aluminium to the strength of geopolymer paste'. Together they form a unique fingerprint.

Cite this