Establishing Particle Size Recommendations for Cationic Asphalt Emulsions

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This article presents a detailed study of cationic asphalt emulsions (CSS type) properties. The authors tested two emulsions (CSS-1 and CSS-1H) using physical and performance tests and proposed new particle size recommendations. The article is practical and well-organized, but there are a few unclear points and small issues that should be improved or explained.

I kindly ask the authors to clarify three issues that came to my mind while reading the manuscript.

• Lack of explanation about low IDT results - the CMA mixes did not meet the required minimum IDT strength (310 kPa). The authors mention this but do not explain why it happened or how it affects the conclusions.
• Unclear changes in CSS-1H viscosity of this emulsion changed a lot, especially on the last test day. It’s unclear whether this was just a random change or if the emulsion started to break. Please clarify if you performed any tests (visual or other) to confirm this.
• Small test sample for particle size - the PSA test was done using just one emulsion drop. It might not represent the whole material well. Please explain if you considered testing a larger or better-mixed sample to improve accuracy.

I also have a few questions about the research in the manuscript.
Why did you test only CSS emulsions? Why not include CMS or CRS in the same test plan?
Did you consider using a second stabilizer (like cement) since the CMA mixes did not meet IDT strength limits? Is it possible?
How did you ensure the RAP used in all tests had the same properties?
Could the viscosity change of CSS-1H on day 184 mean that the emulsion was starting to break? How did you check this?
How did you ensure that the one-drop sample used for PSA was well-mixed and represented the whole emulsion?
Since DST results did not show clear trends, is this test sensitive enough? Could another test be better?

This article is helpful and contributes to better asphalt emulsion standards. However, some methods and explanations need to be improved. I suggest accepting the article after major revisions and adding some missing information.

Author Response

Please see attached file for responses.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

Dear authors, I have prepared some comments for improving this article: 1. The abstract should provide a more precise breakdown of the research methodology, including the materials and testing techniques. Additionally, key quantitative findings should be included to enhance its informativeness. 2. The introduction should better highlight the research gap. While the study mentions the importance of sustainable construction materials, it lacks a direct comparison with prior studies that have attempted similar innovations. 3. Expand the literature review to include more recent relevant studies (preferably from the last five years) on similar materials. 4. The methodology lacks sufficient detail regarding sample preparation, mixing ratios, curing conditions, and testing standards. 5. The manuscript presents experimental results but does not discuss statistical significance or error margins. Adding standard deviation, confidence intervals, or ANOVA results would strengthen the reliability of the findings. 6. The discussion should address how the results align or contrast with existing studies. 7. The manuscript should explicitly discuss how the obtained results compare with similar studies in the field. I think providing a comparative table summarizing key properties of similar materials would be beneficial. 8. Some terms and abbreviations are used without prior. 9. The conclusion should summarize the findings and highlight the study's practical implications. Discussing potential applications, scalability, and limitations would provide more depth.

Author Response

Please see attachment for reply.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

My comments have been addressed by the authors. The article is now more detailed and enriched with the aspects I previously pointed out.

Reviewer 2 Report

Comments and Suggestions for Authors

I think that this version of the article can be published in the journal.