Document Type : Research Paper


1 Civil Engineering Dept., University of Technology-Iraq, Alsina’a street, 10066 Baghdad, Iraq.

2 Civil Engineering Department, University of Technology - Iraq

3 Civil Engineering, University of Technology, Baghdad, Iraq


One of the most user-friendly alternatives to ordinary concrete is geopolymer concrete(GPC), which achieves the same result. GPC is a unique substance made by activating source materials with a high concentration of silica and alumina. As a result, geopolymer binders use less raw resources and emit less carbon dioxide. For these reasons, most academics are focusing on these sorts of resins to develop eco-friendly housing. This article reports on an experimental investigation that examined the Mechanical Performance of Blended Fly Ash based Geopolymer concrete at 7,28 and 360 days made with two different activator solution molarities and varying R (SiO2/Al2O3) ratios. Positive findings were seen at a larger percentage of GGBS (36%) with a concentration of a sodium hydroxide solution of 10 M and an R ratio of 2.75, compared with other proportions. The test findings indicate that increasing the concentration of sodium hydroxide (NaOH) solution and R enhances the compressive strength and decreases water absorption of geopolymer concrete.

Graphical Abstract


  • The mechanical strength of Geopolymer concrete increase with an increase SiO2/Al2O3 ratio.
  • The substitution of GGBS with fly ash will increase the strength of concrete and reduce its workability.
  • Increasing the molarity of NaOH led to increased compressive, tensile, and flexural strength.
  • The workability increases with the fly ash content and decreases as NaOH concentration increases.
  • The substitution of metakaolin with fly ash will reduce the strength and workability. 


Main Subjects

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