Studies on Optimization of Fly Ash, GGBS and Precipitated Silica in Geopolymer Concrete

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

The article, Studies on Optimization of Fly Ash, GGBS and Precipitated Silica in Geopolymer Concrete, presents a timely and relevant study focusing on sustainable alternatives to traditional concrete using industrial byproducts and novel additives. The authors tackled both the mechanical and microstructural aspects of hybrid geopolymer concrete, which is commendable. The following are comments for the authors.

• The novelty as well as the used methodology, should be highlighted in the abstract. What was the kind of the tested specimens? What were the percentages of these materials?
• Several awkward or incorrect phrases (For example: "Concrete is a widely used as construction material after water in global usage" in line 28). Please check the technical writing as well as the grammar of this manuscript.
• Lines 76-84: The research gap should be more sharply defined: What specifically hasn’t been studied? Why is this important?
• Section 2.1: Alkali Activator preparation (NaOH and Na₂SiO₃) could use more detail. For example, mixing procedure, curing temperature, and activation time.
• Section 2.3.3: Please mention the equipment make/model, magnification used, and preparation protocols in more detail to ensure reproducibility.
• The caption of Table 1 should be revised. It can be “Mix Proportions”.
• Section 3: A table summarizing all strength data (7, 28, 90 days compressive and tensile) should be provided to improve clarity significantly.
• Many grammatical issues reduce readability. Examples: “The slump values ranged between 22.5mm to 25mm, indicting a low workability.” “indicting” should be “indicating”, “Set 1 and Set 3 recorded 25mm average slump values exhibiting…” Missing punctuation and awkward phrasing. Repetitive sentence openings: “Set 1 showed… Set 2 showed…” becomes monotonous.
• The result that GGBS/FA drops 35.46% in strength from 28 to 90 days is surprising and demands further explanation (Was it due to shrinkage or incomplete reaction). Also, the authors need to mention this reduction in section 3 when discussing the experimental results.
• Section 3.4: SEM images are visually referenced but lack detailed quantitative insight. For example, no mention of average pore size, gel morphology, or porosity estimates is given. The use of descriptors like "well compacted" or "loose particles" is too general.
• Conclusion section: The section reads like a bullet list disguised as prose. A conclusion should synthesize, not just list, the findings. Each sentence begins with “FA/C exhibited…”, “GGBS/C showed…”, etc., which sounds more like a results table than a reflection.
• The conclusion fails to link findings back to the larger context of sustainable concrete or geopolymer adoption.
• There’s no mention of practical implications, limitations, or future work.

Author Response

Thank you very much for the valuable suggestions and comments.

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

please, see the file attached

Comments for author File: Comments.pdf

Comments on the Quality of English Language

a revision of English could improve the reading of the text

Author Response

Thank you for your valuable suggestions. 

Please see the attachment. 

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

The authors have addressed most of the reviewer's comments.