Fundamental Properties of Steam-Cured Cementitious Composites Incorporating Fine Volcanic Glass Powder

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

• Table 1 gives the brief information of raw materials and more information including strength and physical parameters should be given.
• 2 gives appearance and SEM images of binder and it should be given in materials part.
• The W/B values are very low in this study and the increased W/B due to the decreasing weight of binder will have significant influence on strength development. This should be discussed in details.
• About the curing regimen, the steam curing temperature is 60-80℃, is it the same as the real factory production? On the other hand, the air-curing humidity was selected at 60%, why?
• 9 just presents the appearance of mortar samples and these surface pores formed due to the inappropriate compaction and it is difficult to define the influence on strength. More data such as MIP should be used to explain the strength reduction.
• From the introduction part, it is very difficult to find the novelty of this study.

Author Response

Responses to the Comments of Reviewer 1:
Dear Reviewer,
We sincerely appreciate your time and effort in reviewing our manuscript again and for
providing valuable comments and suggestions. Your insights have significantly contributed to
improving the quality of our work. We have carefully addressed your comments and revised
the manuscript accordingly. Below, we provide itemized responses to each of the listed
comments. All changes in the manuscript have been highlighted in red for clarity.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

This manuscript in its current version is inappropriate for publication in this journal. The innovation is nor clearly present in the introduction section. What is the research gap and what is your unique contribution? Moreover, the manuscript lacks microstructure characterizations (such as SEM, XRD, MIP) to confirm the findings from mechanical properties.

Comments on the Quality of English Language

See the comments.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

The study presents an interesting case for using VG as an alternative to SF in high-strength concrete piles (achieving up to 123 MPa). The manuscript recommends an optimal replacement of 20% of OPC with VG and a curing temperature of 70°C to achieve the desired compressive strength. This approach appears promising for the utilization of locally available construction materials. However, several issues need to be addressed before the manuscript can be considered for publication:

1. Mixing Procedure:
   The manuscript does not clearly indicate when the SP is added, although Table 3 (Mix Proportions) lists SP as a component. Please clarify the timing and role of SP during the mixing process.
2. Air Entrapment and Compressive Strength:
   In lines 230–233, the authors attribute the decrease in compressive strength of the SF 20-80°C sample to air escaping from inside and residing at the surface, as compared to the VG 20-80°C sample (as shown in Figure 9). Could you explain why this phenomenon does not occur in the VG 20-80°C sample or in other samples? Additionally, please discuss whether the inclusion of SP (if applicable) might influence the air void content in the mortar.
3. Data Replication and Variability:
   Please specify the number of parallel samples used to calculate the average compressive strength values presented in Figures 7 and 8. It would also be beneficial to include error bars to represent the data variability for each point.
4. Definition of Maturity and Activity Indices:
   In lines 248–252, the manuscript defines the “maturity index” and “activity index.” Please provide the relevant standards or supporting evidence that these definitions are based on.

Author Response

Please see the attached file.

Author Response File: Author Response.pdf

Reviewer 4 Report

Comments and Suggestions for Authors 1. The research object of this paper is high - strength precast concrete piles. However, the research objects in Figures 6 - 12 in the paper are all mortars. It is recommended to supplement relevant data of concrete to make it closer to reality. 2.  Please explain the basis and significance of the fitting in Figure 10 and Figure 11? 3.  Please mark the 1 - day compressive strength of VG20 - 70 in Figure 14. 4. The conclusion needs to be more concise and clear.

maturity index

Comments on the Quality of English Language

No

Author Response

Please see the attached file.

Author Response File: Author Response.pdf

Reviewer 5 Report

Comments and Suggestions for Authors

This manuscript studied volcanic glass powder incorporated into cementitious materials, for which some properties were evaluated. The manuscript's subject fits into the Applied Sciences Journal and is well structured. Before publication, it is necessary to provide some manuscript improvements.

Please improve the requirements listed below in the manuscript:

1) pg. 2, line 44 - change the word "complicating" to one of a scientific-technical order. Also, describe what "complicating its application" represents. Does it mean resistance, workability, or something else?

2) Include the reference source in Figures 1 and 2.

3) pg. 2, line 68 - At the first time that CO₂ appears in the text, you have to describe it, and then you can use the carbon dioxide formula. Include the numbers (values) when you write about low emissions. Compared to what?

4) Table 2 - insert a legend of chemical formulas.

5) Include a legend of the symbols used in Table 3 (below the table) to facilitate the reader's comprehension.

6) Item 2.2.1 - Could you include the laboratory figures (pictures) to show how or the procedure that the mortar specimens were prepared? Did you follow any standards? Please comment on it.

7) item 2.2.2 - Correct the item title. Does this procedure follow any standard? Please comment on it.

From the manuscript statements, it was concluded that the study focused on regional materials in Japan, such as volcanic glass powder and the experiences of this country. On the other hand, it is important

to mention whether the available VG amount is sufficient for industrial application. Also, is the proposed methodology suitable for large-scale applications? Explain in more detail how the cure can be applied when the material is used on a large scale. Another requirement is to compare the experimental results of VG incorporated with other materials. The comparative improves and give support for your research. Try to discuss your results more profoundly. This could be achieved when you present a comparison.

There is a lack of figures of procedures and material (VG) at the laboratory. What was the need/importance of Figure 2 if you did not include yours?

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Comments and Suggestions for Authors

The authors addressed all the comments properly and it can be acceptable.