MECHANICAL PERFORMANCE OF ALKALI-ACTIVATED CONCRETE INCORPORATING RECYCLED AGGREGATES AND STEEL FIBERS

Hilal El-Hassan, Tamer El-Maaddawy, Abdalla Hussein, Jamal Medljy

Research output: Contribution to journalConference articlepeer-review

Abstract

This study evaluates the mechanical performance of alkali-activated concrete cured at ambient conditions and made with recycled aggregates (RA) and steel fibers. The precursor binder was either ground granulated blast furnace slag or a blend of slag and fly ash (3:1 and 1:1). The alkaline activator solution was a blend of sodium hydroxide and sodium silicate. Coarse aggregates were either natural aggregates (NA) or RA, while fine aggregates comprised desert dune sand. Steel fibers were incorporated, in 2%, by volume, in RA-based concrete mixes. Results showed that replacing NA by 100% RA in plain alkali-activated slag concrete led to decreases of 21, 23, and 51% in compressive, tensile splitting, and flexural strengths, respectively. Meanwhile, alkali-activated slag-fly ash blended (3:1 and 1:1) mixes experienced respective losses of up to 65, 50, and 57%. The corresponding properties of alkali-activated counterparts made with 100% RA increased by up to 172, 273, and 167% upon the addition of 2% steel fibers, by volume. Yet, the impacts of RA and steel fiber incorporation on the mechanical properties were more pronounced in concrete mixes having higher fly ash replacement. Alkali-activated slag and slag-fly ash blended concrete mixes incorporating 2% steel fibers, by volume, and 100% RA exhibited equivalent compressive strength and superior tensile splitting and flexural strengths to those of NA-based counterparts.

Original languageEnglish
Pages (from-to)AAC-09-1-AAC-09-6
JournalProceedings of International Structural Engineering and Construction
Volume9
Issue number1
DOIs
Publication statusPublished - 2022
Event4th European and Mediterranean Structural Engineering and Construction Conference, EURO-MED-SEC-4 2022 - Virtual, Online
Duration: Jun 20 2022Jun 25 2022

Keywords

  • Alkali-activation
  • Fly ash
  • Performance evaluation
  • Slag

ASJC Scopus subject areas

  • Building and Construction
  • Architecture
  • Civil and Structural Engineering
  • Safety, Risk, Reliability and Quality

Fingerprint

Dive into the research topics of 'MECHANICAL PERFORMANCE OF ALKALI-ACTIVATED CONCRETE INCORPORATING RECYCLED AGGREGATES AND STEEL FIBERS'. Together they form a unique fingerprint.

Cite this