Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

This manuscript presents a study on the abrasion resistance of granite manufactured sand pavement concrete based on an indoor abrasion tester. The authors need to address the following issues to improve the quality of the manuscript for publication.

1. Referencing style: The authors need to confirm from “Guides to Authors” the correct referencing style of the Coatings journal
2. Introduction: This section is well written, but nothing is written about two key materials mentioned in the abstract, which are river sand (HS) and limestone mechanism sand (SHY). The authors need to include missing information.
3. Table 1: Information on how flexural strength and compressive strength were conducted on P.O 42.5 ordinary Portland cement. This is important because flexural strength and compressive strength are not among common tests done on cement. These tests are done on concrete.
4. Table 2: The authors need to mention the equipment used to conduct and obtain the chemical composition of P.O. 42.5(%).
5. Table 3: The information in this table, especially the cumulative sieve residue, should be plotted in a logarithm graph as a particle size distribution curve.
6. Table 4: The authors provide information on how the crushing value was obtained.
7. Tables 3 and 4: Why are the crushing values for both fine and coarse aggregate within the same range of 11-20%?
8. Materials section: What is the water-reducing agent the authors are referring to in this statement? “The basic technical indices of the water-reducing agent are presented in Table 7.”
9. “The content of stone powder is substituted with 0%, 3%, 5%, 7%, 9%, 12%, and 15% of the cement amount, and these mixtures are named J0, J3, J5, J7, J9, J12, and J15, respectively.” – The authors’ mix proportion design does not have uniform variation, and this could affect the interpretation of results using observable patterns. Substituting with 0%, 3%, 6%, 9%, 12%, 15%, and 18% would have been a better and more accurate design.
10. “…the cube specimen takes 0.00766”—the authors need to indicate the unit of the value ‘0.00766.’
11. Figures 7-12: The authors need to label the observable features such as pores, etc., in the micrographs.

 

Author Response

Study on abrasion resistance of granite manufactured sand concrete based on indoor abrasion tester

Zhitang Li, Yuankuo Wang, Xiaolong Yang, Junlin Liang, Yuanfeng Chen and Minqiang Pan

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Dear Editors and Reviewer 1:

Thank you for your letter and for the reviewers’ comments concerning our manuscript entitled “Study on abrasion resistance of granite manufactured sand concrete based on indoor abrasion tester. These comments are very valuable and very helpful for revising and improving our manuscript, as well as the important guiding significance to our researches. We have studied comments carefully and made corrections which we hope meet with approval. Revised portions are marked in red in the revised manuscript accordingly. Please keep the authors informed if there is any further action needed. The main corrections in the paper and the responds to the reviewer’s comments are as flowing:

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REVIEWER 1:

This manuscript presents a study on the abrasion resistance of granite manufactured sand pavement concrete based on an indoor abrasion tester. The authors need to address the following issues to improve the quality of the manuscript for publication.

 

1) - Referencing style: The authors need to confirm from “Guides to Authors” the correct referencing style of the Coatings journal.

Response: Thank you for your comment. According to your suggestions, we have adjusted the references to conform to the correct citation style of the Coatings journal.

 

2) - Introduction: This section is well written, but nothing is written about two key materials mentioned in the abstract, which are river sand (HS) and limestone mechanism sand (SHY). The authors need to include missing information."

Response: Thank you for your comment. According to your suggestion, I explained the current shortage of river sand in the introduction part, and put forward the application prospect of machine-made sand. At the same time, the performance comparison between limestone manufactured sand and granite manufactured sand is added, which leads to the advantages of granite manufactured sand concrete. The specific additions are as follows:

HS typically exhibits high compressive strength and wear resistance. Its smooth sur-face and rounded particle morphology contribute to improved workability in concrete mixtures, while simultaneously providing enhanced abrasion resistance [1]. However, the high sand consumption of more than 5-billion tons/year made it an increasingly scarce resource [2,3]. （line 46-55）

Kim et al. suggested that the microstructure of HGY concrete is denser and its porosity is lower [10]. These characteristics help reduce water penetration and minimize drying shrinkage. In contrast, SHY concrete, due to its higher void ratio, is more susceptible to environmental influences, thereby compromising the durability of the concrete. Luo et al. postulated that the particle morphology of HGY is typically irregular, polygonal, and has a large aspect ratio, endowing concrete with potential wear resistance [11]. Binici et al. conducted a comparative study on HGY and SHY concrete and analyzed their durability, finding that concrete prepared with HGY exhibits better durability [12]. Sergii et al. discovered that HGY concrete possesses superior wear resistance compared to SHY concrete [13]. Therefore, HGY has high strength and hardness. If it is applied to concrete pavements, it will significantly enhance the wear resistance of the pavements, reduce the occurrence of pavement diseases [12,13]. （line 46-57）

In addition, an appropriate fine sand content helps to enhance the bonding force be-tween the cement paste and aggregates, strengthening the overall wear resistance. If the fi-ne sand content is too high, a large amount of fine sand will adsorb the cement paste，which may lead to uneven distribution of the cement paste[16]. Some aggregate surfaces cannot be fully coated, resulting in weak bonding. On the other hand, if the fine sand content is too low, the contact area between the coarse aggregates and the cement paste is limited, and it is also difficult to form a high-strength bond. During the wear process, the aggregates can easily break away from the cement matrix, causing potholes, spalling and other diseases on the pavement surface, and the wear resistance will decline sharply [17]. （line 67-75）

 

3) - Table 1: Information on how flexural strength and compressive strength were conducted on P.O 42.5 ordinary Portland cement. This is important because flexural strength and compressive strength are not among common tests done on cement. These tests are done on concrete.

Response: Thank you for your comment. The compressive strength and flexural strength of the cement used in this study are derived from the test report provided by the manufacturer. At the same time, we tested the compressive strength and flexural strength of concrete before the study, which was consistent with the test report provided by the manufacturer. Therefore, the compressive strength and flexural strength indexes of concrete are presented in the cement technical indexes.

 

4) - Table 2: The authors need to mention the equipment used to conduct and obtain the chemical composition of P.O. 42.5(%).

Response: Thank you for your comment. According to your suggestion, we have added equipment for obtaining P.O.42.5 (%) chemical composition. （line 135-137）

 

5) - Table 3: The information in this table, especially the cumulative sieve residue, should be plotted in a logarithm graph as a particle size distribution curve.

Response: Thank you for your comments. Based on your suggestion, we have drawn the cumulative sieve residue diagram of fine aggregate, as shown below: （line 151-152）

6) - Table 4: The authors provide information on how the crushing value was obtained.

Response: Thank you for your comment. This study is based on the 'construction sand ' (GB/T 14684-2022) test procedures, the physical properties of fine aggregate indicators (including crushing value) were tested. （line 135-137）

 

7) - Tables 3 and 4: Why are the crushing values for both fine and coarse aggregate within the same range of 11-20%.

Response: Thank you for your comment. In this study, the crushing values of fine aggregates (granite manufactured sand, limestone manufactured sand, and river sand) and coarse aggregates (limestone aggregates) ranged from 11% to 20%. The primary reasons are as follows:

Firstly, the geological properties of the parent rock are crucial. Granite and limestone, used to produce manufactured sand, possess moderate hardness and high inherent strength, which enhances the aggregates' resistance to crushing. River sand, formed through natural erosion processes, typically has sufficient strength.

Secondly, the processing techniques employed in the production of these aggregates ensure they meet the required strength standards. Advanced crushing and screening technologies are utilized to produce manufactured sand with appropriate particle shape, size, and strength. Similarly, limestone coarse aggregates undergo rigorous processing to achieve the desired quality.

Additionally, quality control measures implemented during production help maintain crushing values within the specified range. Producers regularly conduct tests to ensure aggregates conform to relevant standards, such as ASTM or local specifications, which define acceptable crushing value ranges for various applications.

Lastly, the intended application of these aggregates in concrete production also influences the target crushing value range. A crushing value between 11% and 20% is generally acceptable for numerous concrete applications. This indicates that aggregates possess sufficient strength to remain intact during handling and placement, thereby providing adequate support within the concrete matrix. This range ensures that aggregates contribute to the overall durability and strength of the concrete, while not being overly susceptible to crushing or causing workability issues.

 

8) - Materials section: What is the water-reducing agent the authors are referring to in this statement? “The basic technical indices of the water-reducing agent are presented in Table 7.”.

Response: Thank you for your comment. According to your suggestion, we have made a clear description of all the water reducers in the text, as follows:

The admixture utilized in this research is a WYF-H retarding superplasticizer. WYF-H retarding high-efficiency water-reducing agent, which is a transparent or pale yellow liquid, was used with a dosage of 1.0%. （line 173-175）

 

9) - “The content of stone powder is substituted with 0%, 3%, 5%, 7%, 9%, 12%, and 15% of the cement amount, and these mixtures are named J0, J3, J5, J7, J9, J12, and J15, respectively.” – The authors’ mix proportion design does not have uniform variation, and this could affect the interpretation of results using observable patterns. Substituting with 0%, 3%, 6%, 9%, 12%, 15%, and 18% would have been a better and more accurate design.

Response: Thank you for your comment. Thank you for your professional suggestions regarding the design of stone powder replacement ratios. The equidistant intervals (0%, 3%, 6%, 9%, 12%, 15%, 18%) you mentioned would indeed enhance the visualization of data trends, which is crucial for understanding the nonlinear effects of stone powder content.

In this study, the gradient design of 0%, 3%, 5%, 7%, 9%, 12%, and 15% was selected based on the following considerations:

1. Current Research Status (Domestic and International): Existing studies indicate that excessively low or high stone powder content may adversely affect concrete performance. Therefore, increasing the sampling density within the critical range (e.g., 5%–9%) helps capture threshold behaviors.
2. Practical Engineering Requirements:

In real-world applications, the stone powder content in manufactured sand is typically controlled within 5%–15% (referencing GB/T 14684-2022). Focusing on this range ensures practical relevance and guidance for engineering practices.

3. Material Limitations:

When the replacement ratio exceeds 15%, additional admixtures (e.g., viscosity-modifying agents) are required to mitigate adverse effects. Introducing such variables could interfere with isolating the singular impact of stone powder.

Your suggestions are highly insightful for our future research. We plan to adopt equidistant gradients (e.g., 3% intervals) and extend the replacement ratio to 18% in follow-up experiments to further enhance the universality of our conclusions.

 

10) …the cube specimen takes 0.00766”—the authors need to indicate the unit of the value ‘0.00766..

Response: Thank you for your comment. Based on your suggestion, we have added the relevant units, as follows:

S——Abrasion area of specimen（m²），the cube specimen takes 0.00766 m². （line 294）

 

11) Figures 7-12: The authors need to label the observable features such as pores, etc., in the micrographs.

Response: Thank you for your comment. According to your suggestion, we have marked the SEM images. For example:

 

 

Figure 9. Morphology of interface transition zone in concrete with different effective sand contents ((a) S80, (b) S85, (c) S90, (d) S95, (e) S100).

 

 

 

 

 

SUMMARY

According to the reviewers’ comments, we tried our best to revise the manuscript. And the revised portions are marked in red in the revised manuscript accordingly.

We appreciate the above advice of the reviewers very much. The advice will greatly benefit for the improvement of the paper and our future research. We appreciate for Editors/Reviewers’ warm work earnestly, and hope that the correction will meet with approvals of the journal.

Your good advice was very much appreciated.

Once again, thank you very much for your comments and suggestions.

Thank you and best regards.

Yours sincerely,

Yuanfeng Chen

 

Corresponding author:

Yuanfeng Chen

Email: 2210391014@st.gxu.edu.cn

 

 

 

 

 

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The manuscript entitled "Study on Abrasion Resistance of Granite Manufactured Sand Pavement Concrete Based on Indoor Abrasion Tester" investigates the influence of the fine aggregate granulation and origin on the wear resistance of concrete. The study combines macroscopic abrasion tests with SEM and XRD analyses to evaluate the mechanical and microstructural properties of the concrete specimens. While the experimental scope is relevant and potentially valuable for applications in pavement engineering, the scientific presentation suffers from several issues that limit the manuscript’s clarity and credibility.

The manuscript demonstrates numerous shortcomings, most notably in its citation practices, which frequently involve references that are either irrelevant or insufficiently justified within the context of the discussion. Key terms and abbreviations are inadequately defined, and critical methodological details—such as the origin of materials, standards applied, or specific testing procedures—are often missing or vague. Several scientific interpretations, particularly those involving hydration chemistry and microstructural evolution, are speculative and lack robust literature support. 

The authors should thoroughly revise the manuscript to address the issues highlighted in the attached PDF file, where detailed comments and corrections are provided directly in the text.

Comments for author File: Comments.pdf

Comments on the Quality of English Language

The quality of English throughout the manuscript is inadequate for a scientific publication. The text contains numerous grammatical errors, awkward sentence structures, and inconsistent terminology, which significantly hinder the clarity and precision required in academic writing. Many sentences are either incomplete or poorly constructed, leading to ambiguity in meaning and confusion regarding the authors’ intended message. These issues collectively impair the logical flow of the manuscript and make it difficult for readers to follow the methodology, interpret the results, or understand the conclusions. A thorough revision by a professional scientific editor or a fluent English speaker with domain expertise is strongly recommended to ensure the manuscript meets the linguistic standards expected for international publication.

Author Response

Study on abrasion resistance of granite manufactured sand concrete based on indoor abrasion testerr

Zhitang Li, Yuankuo Wang, Xiaolong Yang, Junlin Liang, Yuanfeng Chen, and Minqiang Pan

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Dear Editors and Reviewer 2:

Thank you for your letter and for the reviewers’ comments concerning our manuscript entitled “Study on abrasion resistance of granite manufactured sand concrete based on indoor abrasion tester. These comments are very valuable and very helpful for revising and improving our manuscript, as well as the important guiding significance to our researches. We have studied comments carefully and made corrections which we hope meet with approval. Revised portions are marked in red in the revised manuscript accordingly. Please keep the authors informed if there is any further action needed. The main corrections in the paper and the responds to the reviewer’s comments are as flowing:

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REVIEWER 2:

The manuscript entitled "Study on Abrasion Resistance of Granite Manufactured Sand Pavement Concrete Based on Indoor Abrasion Tester" investigates the influence of the fine aggregate granulation and origin on the wear resistance of concrete. The study combines macroscopic abrasion tests with SEM and XRD analyses to evaluate the mechanical and microstructural properties of the concrete specimens. While the experimental scope is relevant and potentially valuable for applications in pavement engineering, the scientific presentation suffers from several issues that limit the manuscript’s clarity and credibility.

Response: Thank you for your review and comments on our manuscripts. We attach great importance to your insights and are committed to improving the clarity and credibility of our scientific statements. We admit that there are some problems in our current scientific display, which affects the clarity and persuasiveness of the paper. We have revised the full text according to the suggestions of each reviewer. At the same time, we checked the overall expression of the article to ensure the credibility of the paper.

 

The manuscript demonstrates numerous shortcomings, most notably in its citation practices, which frequently involve references that are either irrelevant or insufficiently justified within the context of the discussion. Key terms and abbreviations are inadequately defined, and critical methodological details—such as the origin of materials, standards applied, or specific testing procedures—are often missing or vague. Several scientific interpretations, particularly those involving hydration chemistry and microstructural evolution, are speculative and lack robust literature support.

Response: Thank you for your valuable review and comments on our manuscript. We take your feedback very seriously and will comprehensively revise and enhance our paper.

To address the citation issues, we'll thoroughly reevaluate all references to ensure they're highly relevant to the discussions and backed by solid scientific evidence. This means removing unsupported or irrelevant citations and adding more pertinent ones to strengthen our paper's scientific credibility.

Regarding the insufficiently defined key terms and abbreviations, we'll systematically comb through the manuscript. Each technical term and abbreviation will be clearly defined upon first mention, ensuring readers can precisely follow our work.

For the speculative scientific interpretations, particularly those involving hydration chemistry and microstructure evolution, we'll conduct a stricter review. We'll ensure all explanations are firmly supported by existing literature. We'll either reduce speculative content or, where necessary, clearly indicate the assumptions made and back them up with appropriate references.

 

The quality of English throughout the manuscript is inadequate for a scientific publication. The text contains numerous grammatical errors, awkward sentence structures, and inconsistent terminology, which significantly hinder the clarity and precision required in academic writing. Many sentences are either incomplete or poorly constructed, leading to ambiguity in meaning and confusion regarding the authors’ intended message. These issues collectively impair the logical flow of the manuscript and make it difficult for readers to follow the methodology, interpret the results, or understand the conclusions. A thorough revision by a professional scientific editor or a fluent English speaker with domain expertise is strongly recommended to ensure the manuscript meets the linguistic standards expected for international publication.

Response: Regarding the quality of English manuscripts, we realize that there are a large number of grammatical errors, embarrassing sentence structures and inconsistent terms in the text, which greatly hinder the clarity and accuracy required in academic writing. We will carefully examine and correct all grammatical errors, optimize sentence structure to eliminate ambiguity, and unify the use of terms to improve the clarity and professionalism of the paper.

Questions in the PDF:

1. To improve the application and development of granite manufactured sand (HGY) concrete pavement in engineering. ——It appears that the second part of the sentence is incomplete or missing.

Response: Thank you for your comment. According to your suggestion, we have modified this sentence, as follows:

The long-term wear resistance of granite manufactured sand (HGY) concrete pavements has not been sufficiently investigated. This deficiency makes it difficult to accurately predict and evaluate the service life and durability of such pavements in practical engineering applications. （line 8-11）

 

2. How does reference [9] address this issue, given that it focuses on "(...) the Influence of Copper Slag on the Properties of Cement-Based Materials"?

Response: Thank you for your comment. The purpose of quoting the literature is to discuss the impact of fine sand content on cement-based materials. The copper slag described in the literature is also used as a fine aggregate, and the influence of its cement-based material is studied.

 

3. What do the authors mean by "effective sand content"?

Response: Thank you for your comment. This statement is indeed wrong, and we have corrected it. Change to the content of fine sand.

 

4. How does reference [11] address this concern, given that the article pertains solely to a method for sand quality control?

Response: Thank you for your question. The purpose of citing this literature is to demonstrate that too high or too low fine sand content will lead to unreasonable gradation, thus affecting the wear resistance of concrete, so as to lead to the research content of the article-the influence of effective sand content on the long-term wear resistance of granite machine-made sand concrete pavement.

 

5. However, if the content of coarse particles is too high, it will lead to excessively large voids between the particles, which are difficult to be fully filled by fine particles and cement paste ^[13]. ——Please provide a justification for the use of this reference in this context.

Response: Thank you for your comment. I 'm sorry that due to our negligence, we have cited irrelevant references. We have deleted the literature and cited other relevant literature to demonstrate this view. The reasons for citing the literature are as follows:

Literature: Kai-ren, L.; Ping-Li, H. Research on the Influence of Manufactured Sand Gradation on Concrete Performance. E3S Web of Conferences 2021, 283, 01024, doi:10.1051/e3sconf/202128301024

Reasons: When the fineness modulus of manufactured sand is too large, that is, the proportion of coarse particles is too high, it will lead to the aggregate gap cannot be fully filled by fine particles, which is prone to segregation and bleeding, which will affect the compressive strength of concrete. This shows that too high proportion of coarse particles will hinder the effective filling of voids by fine particles, thus reducing the overall performance of the material.

 

6. In some pavements with high requirements for surface flatness and smoothness, an appropriate increase in the content of fine particles helps to reduce surface irregularities, lowering the friction coefficient and reducing wear ^[14]. ——This reference does not appear to be relevant to the sentence.

Response: Thank you for your comment. I 'm sorry that due to our negligence, we have cited irrelevant references. We have deleted the literature.

 

 

7. However, if the content of fine particles is too much, it will increase the specific surface area of the concrete. ——What is meant by the specific surface area of concrete in this context?

Response: Thank you for your comment.  The specific surface area of concrete refers to the ratio of the total surface area of all particles (such as cement, aggregate, etc.) in concrete to the total volume of concrete. It reflects the fineness of particles in concrete and the size of the total surface area.

 

8. There are relatively few comparative studies on the wear resistance between HGY concrete and other lithological MS concrete. ——The authors should refer to these few relevant studies.

Response: Thank you for your comment. We have modified the description and cited the corresponding references. The specific contents after modification are as follows:

Additionally, comparative analyses of the abrasion resistance of HGY concrete versus other types of mechanism sand (MS) concrete are extremely limited [11]. This scarcity of research hinders the comprehensive evaluation of the performance advantages and practical applicability of HGY concrete relative to other concrete types. Moreover, the current research focus on HGY concrete predominantly emphasizes its durability characteristics [24,25]. Systematic studies on the evolutionary trend of abrasion resistance of HGY concrete pavements over extended periods of service, including factors such as the magnitude and rate of abrasion resistance changes at different service stages, have not been thoroughly conducted. （line 106-113）

 

9. Most of the existing studies focus on short-term wear resistance ——The authors should refer to these few relevant studies.

Response: Thank you for your comment. According to the reviewer 's suggestion, we have made some modifications to the introduction of the paper.

First, we changed this sentence to “Most of the existing studies focus on durability resistance of HGY concrete, and there is a deficiency in systematic research on the evolution law of the wear resistance of HGY concrete pavements during long-term use”. Secondly, the corresponding references are added. The references added are as follows:

Zheng, S.; Chen, J.; Wang, W. Effects of Fines Content on Durability of High-Strength Manufactured Sand Concrete. MATERIALS 2023, 16, doi:10.3390/ma16020522.

2Wang, J.; Yang, Z.; Liu, Y. Effects of the Lithologic Character of Manufactured Sand on Properties of Concrete. JOURNAL OF WUHAN UNIVERSITY OF TECHNOLOGY-MATERIALS SCIENCE EDITION 2014, 29, 1213–1218, doi:10.1007/s11595-014-1070-

 

10. The cement utilized in this study was a P.O 42.5 ordinary Portland cement, with its

basic parameters enumerated in Table 1 and the chemical composition depicted in Table 2.——The source or manufacturer of the cement should be clearly specified. The authors should indicate the standards used to determine these parameters.

Response: Thank you for your comment. According to your suggestion, we explain the source of cement and the quality standard of cement parameters. Specifically as follows:

The cement used in this study is P.O 42.5 ordinary Portland cement produced in Nanning area, and the quality meets the relevant requirements of ' general Portland cement ' GB175. The basic parameters are listed in Table 1. （line 133-135）

 

11. The cement utilized in this study was a P.O 42.5 ordinary Portland cement, with its

basic parameters enumerated in Table 1 and the chemical composition depicted in Table 2.

Response: Thank you for your comment. According to your suggestion, we have clearly explained the method of quantifying the chemical composition of cement. （line 135-137）

 

12. Table 3. Cumulative sieve residue and fineness modulus of fine aggregate grades. —（It would be more effective to present the results of the sieve analysis in a figure rather than in a table.）

Response: Thank you for your comment. According to your suggestion. Based on your suggestion, we have drawn the cumulative sieve residue diagram of fine aggregate, as shown below: （line 151-152）

 

13. The method used to determine the chemical composition of HGY should be clearly stated.

Response: Thank you for your comment. The chemical composition of HGY stone powder was detected by X-ray fluorescence spectrometer. （line 170-171）

 

14. Table 6. Chemical compositions of HGY stone powder. ——（The method used to determine the chemical composition of HGY should be clearly stated.）

Response: Thank you for your comment. Based on your suggestion, we have defined MS clearly. Manufactured sand (MS)

15. Including information on the geometric dimensions of each aggregate fraction would be helpful here.

Response: Thank you for your comment. We sincerely appreciate your insightful suggestion regarding the 'geometric size information of aggregate fractions.' This information would indeed provide a more comprehensive characterization of the material properties. In the current study, our primary focus was on investigating the abrasion resistance of concrete, which led us to prioritize chemical composition analysis over systematically collecting detailed data on particle geometry. This represents a limitation of the current research framework. In response to your recommendation, we plan to prioritize this issue in follow-up investigations, incorporating advanced particle morphology characterization techniques (e.g., laser granulometry or SEM-EDS mapping) to establish quantitative correlations between geometric parameters and material performance.

 

16. Upon the completion of specimen preparation, subsequent tests regarding abrasion

resistance are then conducted. ——（The authors should specify the curing time and regime applied in the study.）

Response: Thank you for your comment. We have determined the curing time and standard of concrete in the study. The details are as follows:

Through the self-made ring mold, the concrete was poured according to the 'High-way Engineering Cement and Cement Concrete Test Regulations’ and the specimens were standardly cured for 28 days. （line 271-273）

 

17. XRD Analysis

Response: Thank you for your comment. We are sorry for the inconvenience caused to you due to our negligence, we have modified it. （line 300）

 

18. As the effective sand content increases, a higher proportion of fine aggregates with smaller particle sizes is present, leading to an enhance cement in the strength of the cement paste. Consequently, the mass loss during abrasion decreases ^[25,26] —(How do the authors justify the use of these references in this context? What is the rationale for including them here at all?)

Response: Thank you for your comment. We are sorry that we have cited these two references to unrelated places. We want to demonstrate that the increase in the proportion of fine aggregate will increase the strength of cement slurry. At the same time, we put these two references in the position of the previous sentence.

 

19. The abbreviations 2w, 4w, and 6w should be clearly defined.

Response: Thank you for your comment. According to your suggestion, we define the abbreviations 2w, 4w and 6w clearly. Specific as follows:

Figure 5. Mass loss. ((a) effective sand content; (b) stone powder content; (c) fine aggregate lithology))  Note：2w- the cube specimen was worn 20000 times.; 4w- the cube specimen was worn 40000 times; 6w- the cube specimen was worn 60000 times. （line 346-348）

 

20. The results indicate that after 20,000 abrasion cycles, as the number of abrasion cycles in-creases, the mass loss of each specimen decreases. —How do the authors explain this phenomenon?

Response: Thank you for your comment. According to your question, we will explain this and describe it in the corresponding position of the original text and quote the relevant references to support it. The details are as follows:

This is because in the initial stage of wear (20000 wear cycles), pores and cracks are the main sources of concrete mass loss, as wear particles tend to detach easily from these weak areas. As the number of wear cycles increases, stone powder fills and blocks these pores and cracks, thereby densifying the internal structure of the material [36].（line 321-325）

 

21. The mass loss of the different fine aggregates follows the descending order: HS >

SHY > HGY. （—Is the mass loss referring to the different fine aggregates themselves, or to the concrete made with different fine aggregates?）

Response: Thank you for your comment. HS > SHY > HGY refers to the mass loss of concrete ring specimens prepared with different fine aggregates. To express this point more clearly, we changed HS > SHY > HGY into HS > SHY > HGY concrete specimens.

 

22. when the effective sand content continuously increases, the microscopic morphology of the cement paste surface becomes more compact. When the effective sand content ranges from 80% to 90%, the hydration products are randomly and loosely piled on the surface of the cement paste, resulting in many small pores. When the effective sand content is 95% and 100%, the microscopic morphology of the cement paste surface is dense. （—Which figures illustrate this phenomenon?）

Response: Thank you for your comment. Figure 7 is an argument for this sentence. To see this phenomenon more intuitively and clearly, we mark the observable features in the micrograph.

.    

 

 

Figure 6. Microstructures of the cement stone in concrete with different effective sand contents ((a) S80, (b) S85, (c) S90, (d) S95, (e) S100).

 

23. Figure 7. The microscopic morphology of the cement pastes in concrete with different effective sand contents ((a) S80, (b) S85, (c) S90, (d) S95, (e) S100)（—(1) The authors should indicate the observed phases in the SEM micrographs, for example by using arrows or labels. (2) By definition, cement paste does not contain any aggregate, so how could the effective sand content influence its morphology?）

Response: Thank you for your comment. According to your suggestion, we have marked the microstructure of concrete cement stone. The concrete specimens that have been maintained for 28 days were smashed, the coarse aggregate was removed and the cement stone between the aggregates was collected. After grinding into powder, the scanning electron microscope test was performed. At the same time, we modified the name of the micro-topography.

.    

 

 

Figure 6. Microstructures of the cement stone in concrete with different effective sand contents ((a) S80, (b) S85, (c) S90, (d) S95, (e) S100).

24. However, when the dosage is too high, it will result in relatively large hole sizes in the formed concrete, and the stone powder cannot completely fill these holes (—How do the authors explain this phenomenon?）

Response: Thank you for your comment. When the content of stone powder is too high, the stone powder particles themselves are relatively fine. Too much stone powder will cause the particle gradation inside the concrete to be unbalanced, and it cannot play an ideal filling role in the skeleton, resulting in the formation of large voids or holes inside the concrete. And we explain the corresponding position in the text.

 

25. Moreover, the addition of a large amount of stone powder will impede the cement hydration process and reduce the generation of hydration products. (—This claim should be supported by an appropriate reference.）

Response: Thank you for your comment. According to your suggestion, we have added references in the corresponding position.

 

26. This is because the stone powder contained in the MS can provide crystal nuclei points during the cement hydration process, promoting the formation of cement hydration products. (—This claim should be supported by an appropriate reference.）

Response: Thank you for your comment. According to your suggestion, we have added references in the corresponding position.

 

27. Figure 9. Morphology of cement stone in concrete with different fine aggregate lithology ((a) HS, (b) SHY, (c) HGY). (—Figure 9b is not legible in its current form.）

Response: Thank you for your comment.  Thank you for pointing out the problem that the figure is not clear. Due to the current objective conditions, we have been unable to shoot again to replace this picture. Nevertheless, we will try to explain the key information conveyed by the figure in detail through the text in the subsequent expression of the paper to make up for this deficiency.

 

28. Figure 9. Morphology of cement stone in concrete with different fine aggregate lithology ((a) HS, (b) SHY, (c) HGY). (—The aggregate in each of these micrographs should be visually distinguished from the cement paste, for example through illustrative marking.）

Response: Thank you for your comment. According to your suggestion, we have visually distinguished the aggregates and cement pastes in the micrographs by illustrative markers.

 

 

Figure 8. Microstructures of the cement stone in concrete with different fine aggregate lithology ((a) HS, (b) SHY, (c) HGY).

 

 

29. This shows that in the specimens with a low effective sand content, Ca (OH)₂, which would originally participate in the carbonation reaction, will continue to undergo a hydration reaction with SiO₂ under a high effective sand content, thereby increasing the hydration degree of the concrete. (—Since the SiO2 was probably primarily present in the mineral form of quartz (sourced from sand), as the authors should explicitly state, given that XRD analysis was conducted and would have confirmed this, they need to clarify under what conditions portlandite could react with quartz. Quartz, being a crystalline and chemically inert form of silica, does not typically react with portlandite under standard curing conditions. Therefore, the authors must specify the environmental or chemical circumstances under which such a reaction could occur, and support this claim with appropriate literature references. Otherwise, attributing any observed interaction between portlandite and quartz to a direct chemical reaction would be scientifically unfounded.）

Response: Thank you for your comment. Firstly, we fully agree with your view that quartz is a crystalline and chemically inert mineral, so the possibility of a direct chemical reaction between calcium hydroxide and quartz under conventional concrete curing conditions is extremely low. In our experiment, the silica in the sand used mainly exists in the form of quartz, and we can further confirm this and make it clear through XRD analysis results. We will supplement the related explanation in the text, pointing out that as the main form of silica in sand, the interaction mechanism between quartz and calcium hydroxide under experimental conditions needs to be discussed more rigorously.

We have reflected that the previous description of the hydration reaction between calcium hydroxide and silica was indeed inaccurate. In fact, the phenomenon we observed may not be a direct hydration reaction between calcium hydroxide and quartz. Instead, it is likely that the change in effective sand content affected the pore structure and chemical environment of the concrete system. This, in turn, indirectly promoted other hydration reactions or subsequent carbonation processes, thereby causing a certain change in the overall degree of hydration. We will revise this part in the text.

The specific description after modification is as follows:

The silica in the sand used mainly exists as quartz, a crystalline silica with high chemical stability that typically doesn't react directly with calcium hydroxide under conventional concrete curing conditions. However, the peak values of the characteristic peaks vary, es-specially for the carbonized products represented by CaCO₃ and the minerals of fine aggregates represented by SiO₂.  When the effective sand content increases to 100%, the contents of CaCO₃ and SiO₂ decrease significantly. In specimens with low effective sand content, calcium hydroxide (Ca (OH)2) mainly participates in the carbonation reaction. In high effective sand content conditions, quartz alters the concrete's pore structure and local chemical environment. This indirectly affects the hydration process by possibly promoting the formation or transformation of other hydration products, thus increasing the overall hydration degree. （line 489-499）

 

 

30. Figure 13. XRD patterns of concrete with different effective sand contents. (—In which mineral forms were each of these phases present within the cement matrix?）

Response: Thank you for your comment. Calcium carbonate (CaCO₃) typically exists in the form of calcite. Silicon dioxide (SiO₂) mainly exists in the form of quartz. Calcium silicate hydrate (C-S-H) usually exists in an amorphous or noncrystalline form. Calcium hydroxide (CH) commonly exists in a crystalline form. Calcium sulfoaluminate hydrate (Aft) often exists in the form of acicular or prismatic crystals.

 

31. It was speculated that the addition of an appropriate amount of stone powder into the concrete could effectively promote the hydration of cement, improve the compactness of the concrete, and reduce the generation of CaCO3 carbonized products at 28d. (—What was the underlying mechanism behind this observation? The authors should provide a more thorough explanation, preferably supported by relevant findings from previous research?）

Response: Thank you for your comment. According to your suggestion, we have modified this description as follows:

Studies have shown that stone powder particles, with their large specific surface area, can adsorb cement hydration products and provide more active surfaces for cement hydration, thus accelerating the cement hydration reaction. In addition, the filling action of stone powder can refine the pore structure within concrete, reduce the number of large pores, and enable cement hydration products to diffuse and fill these pores, thereby promoting further cement hydration more easily. Consequently, adding an appropriate amount of stone powder to concrete can effectively promote cement hydration, increase the compact-ness of the concrete, and reduce the formation of CaCO₃ carbonation products at 28 days. （line 507-516）

32. In a decrease in the content of SiO₂ and an increase in the content of silicate products. (—The same comment applies here as to the previous speculation regarding the amount of SiO2 in the XRD samples. From my perspective, the SiO2 originates from the sand and should therefore be present predominantly in the crystalline form of quartz (it should be checked though). The observed differences between samples are likely attributable to variations in the sand content of the analyzed specimens, rather than to any reaction between portlandite and SiO2?）

Response: Thank you for your comment. You pointed out that SiO₂ is mainly derived from sand and mainly exists in the form of quartz crystal, which is an important inspiration for our research. The following is our further explanation and explanation of related issues.

SiO₂ mainly exists in the form of quartz crystal in sand, which is the main source of SiO₂ in sand. The formation environment and processing technology of different fine aggregates (river sand, SHY, HGY) are different, resulting in differences in the content and characteristics of quartz crystals. This will directly affect the diffraction signal intensity of SiO₂ in the XRD pattern. Even under the same mix ratio, the amount of sand participating in the XRD test will change due to the different factors such as the bulk density and particle gradation of the fine aggregate, which will lead to the different intensity of the SiO2 characteristic peak.

In summary, we believe that the main reason for the difference of SiO2 content in different fine aggregate concrete in XRD pattern is the difference of quartz crystal characteristics (such as purity, crystal defects, etc.) and sand content in sand, rather than the direct conversion of SiO₂ by cement hydration reaction. Thank you for your careful guidance of our research, we will further improve the content of the paper according to your suggestions. （line 522-531）

 

 

 

SUMMARY

According to the reviewers’ comments, we tried our best to revise the manuscript. And the revised portions are marked in red in the revised manuscript accordingly.

We appreciate the above advice of the reviewers very much. The advice will greatly benefit for the improvement of the paper and our future research. We appreciate for Editors/Reviewers’ warm work earnestly, and hope that the correction will meet with approvals of the journal.

Your good advice was very much appreciated.

Once again, thank you very much for your comments and suggestions.

Thank you and best regards.

Yours sincerely,

Yuanfeng Chen

 

Corresponding author:

Yuanfeng Chen

Email: 2210391014@st.gxu.edu.cn

 

 

 

 

 

Author Response File: Author Response.pdf

Reviewer 3 Report

Comments and Suggestions for Authors

Please refer to the comments as marked in the manuscript. In addition, more testing are needed to be added (including results and discussion) in this manuscript. 

Comments for author File: Comments.pdf

Comments on the Quality of English Language

English usage needs to be improved. 

Author Response

Study on abrasion resistance of granite manufactured sand concrete based on indoor abrasion tester

Zhitang Li, Yuankuo Wang, Xiaolong Yang, Junlin Liang, Yuanfeng Chen and Minqiang Pan

-----------------------------------------------------------------------------------------------------------------------------

Dear Editors and Reviewer 3:

Thank you for your letter and for the reviewers’ comments concerning our manuscript entitled “Study on abrasion resistance of granite manufactured sand concrete based on indoor abrasion tester. These comments are very valuable and very helpful for revising and improving our manuscript, as well as the important guiding significance to our researches. We have studied comments carefully and made corrections which we hope meet with approval. Revised portions are marked in red in the revised manuscript accordingly. Please keep the authors informed if there is any further action needed. The main corrections in the paper and the responds to the reviewer’s comments are as flowing:

------------------------------------------------------------------------------------------------------------------------------

REVIEWER 3:

1) - Study on abrasion resistance of granite manufactured sand pavement concrete based on indoor abrasion tester. (—The word "pavement" here is very confusing - as this study is merely on concrete.)

Response: Thank you for your comment. According to your suggestion, we have replaced the title of this article with Study on abrasion resistance of granite manufactured sand concrete based on indoor abrasion tester, and checked all the incorrect statements in the article and modified them.

 

2) - To improve the application and development of granite manufactured sand (HGY) concrete pavement in engineering. (—This sentence is incomplete. Please revise.)

Response: Thank you for your comment. According to your suggestion, we have modified the sentence. The details are as follows:

The long-term wear resistance of granite manufactured sand (HGY) concrete has not been sufficiently investigated. This deficiency makes it difficult to accurately predict and evaluate the service life and durability of such concrete pavements in practical engineering ap-plications. (line 9-11)

 

 

3) - From the two dimensions of macroscopic performance and microscopic structure, the mechanisms influence of the effective sand ratio, stone powder content, and fine aggregate lithology on the wear resistance of HGY concrete were systematically investigated. (—HGY stands for?)

Response: Thank you for your comment. HGY refers to granite manufactured sand, and we have explained the position where the abbreviation first appeared. (line 8)

 

 

4) - Introduction. (—It is recommended to extend the write up on critical review of literature. to around 8 paragraphs.)

Response: Thank you for your comment. According to your suggestion, we have changed the introduction to 8 paragraphs. (line 34-130)

 

 

5) - To achieve the low-carbon, economic, and sustainable development of the construction industry, manufactured sand (MS) concrete has emerged as the focus of research and application. (—In general, the English usage (sentences) in this manuscript needs to be improved. It is recommended for the authors to send this work to be proof read or revised by the professional English proof reader before it can be considered for publication in Coatings.)

Response: Thank you for your comment. We realize that there are a large number of grammatical errors, embarrassing sentence structures and inconsistent terms in the text, which greatly hinder the clarity and accuracy required in academic writing. We will carefully examine and correct all grammatical errors, optimize sentence structure to eliminate ambiguity, and unify the use of terms to improve the clarity and professionalism of the paper.

 

6) - The effective sand content is one of the key factors affecting the concrete gradation.

Either an excessively high or low effective sand content will lead to an unreasonable gradation, thus affecting the wear resistance of the concrete. Existing studies have shown that appropriately increasing the content of coarse particles in HGY can, to a certain extent, enhance the skeletal function of concrete. Coarse particles can bear more external forces and play a certain resistant role when subjected to wear such as friction, contributing to the improvement of the initial wear resistance of concrete. However, if the content of coarse particles is too high, it will lead to excessively large voids between the particles, which are difficult to be fully filled by fine particles and cement paste. This will make the internal structure of the concrete loose. During long-term use, external moisture, dust and other impurities can easily enter these voids, accelerating the wear and damage of the concrete. For HGY, fine particles can increase the bonding area between the cement paste and aggregates, improving the bonding force and thus enhancing the wear resistance of the concrete to a certain extent. In some pavements with high requirements for surface flatness and smoothness, an appropriate increase in the content of fine particles helps to reduce surface irregularities, lowering the friction coefficient and reducing wear. However, if the content of fine particles is too much, it will increase the specific surface area of the concrete, requiring more cement paste to wrap it, thus increasing the water consumption15. Excessive water will form pores inside the concrete, reducing the strength and compactness of the concrete and instead decreasing the wear resistance. (—This is a good write up, but it seems a bit general. As a reader, I am looking for a critical review of literature.)

 

Response: Thank you for your comment. According to your suggestion, we have modified this passage. The details are as follows:

In addition, an appropriate fine sand content helps to enhance the bonding force be-tween the cement paste and aggregates, strengthening the overall wear resistance. If the fine sand content is too high, a large amount of fine sand will adsorb the cement paste, which may lead to uneven distribution of the cement paste. Some aggregate surfaces cannot be fully coated, resulting in weak bonding. On the other hand, if the fine sand content is too low, the contact area between the coarse aggregates and the cement paste is limited, and it is also difficult to form a high-strength bond. During the wear process, the aggregates can easily break away from the cement matrix, causing potholes, spalling and other diseases on the pavement surface, and the wear resistance will decline sharply.

The sand content within the range of 0.075 mm to 2.36 mm is one of the key factors influencing the concrete gradation. Either an excessively high or low fine sand content will lead to an unreasonable gradation, thus affecting the wear resistance of the concrete. Li et al. have shown that the wear resistance of MS concrete is closely correlated with its sand content. When the sand content is within an optimal range (e.g., 20%-35%), MS concrete exhibits better wear resistance, as this optimal sand content facilitates more uniform particle distribution and a denser microstructure. Other studies have shown that appropriately increasing the content of coarse particles in MS can, to a certain extent, enhance the skeletal function of concrete. Coarse particles can bear more external forces and play a certain resistant role when subjected to wear such as friction, contributing to the improvement of the initial wear resistance of concrete. However, if the content of coarse particles is too high, it will lead to excessively large voids between the particles, which are difficult to be fully filled by fine particles and cement paste. This will make the internal structure of the concrete loose. During long-term use, external moisture, dust and other impurities can easily enter these voids, accelerating the wear and damage of the concrete.

Therefore, in some MS concrete pavements with high requirements for surface flatness and smoothness, an appropriate increase in the content of fine particles helps to re-duce surface irregularities, lowering the friction coefficient and reducing wear. Within an optimal range, limestone powder content can enhance the durability and density of concrete. However, exceeding this optimal threshold can detrimentally impact the hardened MS concrete's wear resistance. Conversely, insufficient limestone powder content restricts its physical filling capacity and hydration-promoting effects, resulting in only marginal improvements to the mechanical and durability-related properties of MS concrete. (line 67-100)

 

8) - Global research initiatives have ascertained that HGY concrete exhibits good wear resistance. However, for HGY concrete, the optimal stone powder content and effective sand ratio when the wear resistance thereof reaches the optimum level have not yet been clearly defined. There are relatively few comparative studies on the wear resistance between HGY and other lithological MS, rendering it arduous to conduct a comprehensive evaluation of the superiority and applicability of HGY. Most of the existing studies focus on short-term wear resistance, and there is a deficiency in systematic research on the evolution law of the wear resistance of HGY concrete pavements during long-term use. (—This paragraph is a bit general.)

 

Response: Thank you for your comment. According to your suggestion, we have adjusted this passage, as follows:

Global research has extensively confirmed that HGY concrete exhibits superior abra-sion resistance. However, the optimal content of stone powder and fine sand required to maximize the abrasion resistance of HGY concrete remains unclear, with existing studies and experimental data failing to provide a precise range or standard value. Additionally, comparative analyses of the abrasion resistance of HGY concrete versus other types of mechanism sand (MS) concrete are extremely limited[11]. This scarcity of research hinders the comprehensive evaluation of the performance advantages and practical applicability of HGY concrete relative to other concrete types. Moreover, the current research focus on HGY concrete predominantly emphasizes its durability characteristics[24,25]. Systematic studies on the evolutionary trend of abrasion resistance of HGY concrete pavements over extended periods of service, including factors such as the magnitude and rate of abrasion resistance changes at different service stages, have not been thoroughly conducted. This significant research gap restricts the accurate prediction and effective assessment of HGY concrete’s long - term performance in practical applications. (line 102-115)

 

 

7) - 3.1.1. Effect of effective sand content on abrasion resistance of concrete. (—Sections 3.1.1, 3.1.2 and 3.1.3 can be combined as one section only, there is no need to saperate between them.)

Response: Thank you for your comment. According to your suggestion, we merge these three sections.

 

8) - Figure 4. Mass loss under different effective sand content. (—Figures 4 until 6 can be combined as one figure only, for example, Figure 4(a-c). Please revise.)

Response: Thank you for your comment. According to your suggestion, we combine the three diagrams as follows:

Figure 4. Mass loss. ((a) effective sand content; (b) stone powder content; (c) fine aggregate lithology)) Note: 2w- the indoor abrasion tester rotates 10000 times; 4w- the indoor abrasion tester rotates 20000 times; 6w- the indoor abrasion tester rotates 30000 times.

 

9) - Figures 13 - 15 can be combined as one figure only. for example, Figure 13 (a-c). Please revise.

Response: Thank you for your comment. According to your suggestion, we combine the three diagrams as follows:

   

9) - This study, a self-developed indoor abrasion tester for concrete pavements was utilized. Taking the mass loss as the evaluation index and combining with SEM and XRD testing technologies, revealed the influence mechanisms of the effective sand content, stone powder content, and fine aggregate lithology on the wear resistance of HGY pavement concrete. It determined the optimal contents of the effective sand content and stone powder content and explored the decay law of the long-term wear resistance of concrete pavements. The study improves road safety, durability, and reduces maintenance costs, providing valuable guidance for engineering practices. (—English usage needs to be improved.)

Response: Thank you for your comment. According to your suggestion, we combine the three diagrams as follows:

In this study, a self-developed indoor abrasion tester for concrete pavements was employed. Using mass loss as the evaluation metric, combined with scanning electron microscopy (SEM) and X-ray diffraction (XRD) analyses, this study elucidated the mechanisms by which effective sand content, limestone powder content, and fine aggregate lithology influence the abrasion resistance of high-grade granite (HGY) concrete. The study identified optimal thresholds for effective sand and limestone powder ratios and quantified the long-term degradation kinetics of abrasion resistance in HGY concrete pavements. These findings enhance road safety and durability while reducing maintenance costs, offering actionable insights for optimizing HGY concrete in engineering applications. (line 537-546)

 

10) - For a full technical paper, it is recommended to have around 35-45 references for critical review of literature.

Response: Thank you for your comment. Based on your suggestions, we have added 42 references. Finally, we have made a unified change to the reference format of the full text.

In this study, from the performance test of raw materials to the related experiments of concrete, the reference standard is the Chinese specification, as follows:

GB/T 14684-2022, Sand for Construction[S].; 2022.

  GB/T 14685-2011,Pebble and Crushed Stone for Construction[S].; 2011.

   GB 8076-2008,Concrete Admixtures[S].; 2008.

   GB/T 1596-2005,Fly Ash Used for Cement and Concrete[S].; 2005.

GB 5749-2006,Standards for Drinking Water Quality[S].; 2006.

 

 

 

 

SUMMARY

According to the reviewers’ comments, we tried our best to revise the manuscript. And the revised portions are marked in red in the revised manuscript accordingly.

We appreciate the above advice of the reviewers very much. The advice will greatly benefit for the improvement of the paper and our future research. We appreciate for Editors/Reviewers’ warm work earnestly, and hope that the correction will meet with approvals of the journal.

Your good advice was very much appreciated.

Once again, thank you very much for your comments and suggestions.

Thank you and best regards.

Yours sincerely,

Yuanfeng Chen

 

Corresponding author:

Yuanfeng Chen

Email: 2210391014@st.gxu.edu.cn

 

 

 

 

 

Author Response File: Author Response.pdf

Reviewer 4 Report

Comments and Suggestions for Authors

Good research topic and relevant to the journal theme. Adequate data collection. Perhaps correlation between different properties would be useful. Comments include:

 

HGY..is it the right acronym

 

 

 

 

Page 2..What is meant by the first sentence of the second paragraph

 

 

IMPROVE THE SENTENCE…Nanning local tap water is used for drinking water, which meets the ' Standards for drinking water quality ' (GB5749-2006 ) 21.

 

Table 9..what is the difference between adjusted sand and effective sand. Where si the stone powder or is it in Table 10

 

Equation 1..abrasion area of specimen…not fully described

 

Caption of figure 6. Lithology??..type??

Author Response

Study on abrasion resistance of granite manufactured sand concrete based on indoor abrasion tester

Zhitang Li, Yuankuo Wang, Xiaolong Yang, Junlin Liang, Yuanfeng Chen and Minqiang Pan

-----------------------------------------------------------------------------------------------------------------------------

Dear Editors and Reviewer 4:

Thank you for your letter and for the reviewers’ comments concerning our manuscript entitled “Study on abrasion resistance of granite manufactured sand concrete based on indoor abrasion tester. These comments are very valuable and very helpful for revising and improving our manuscript, as well as the important guiding significance to our researches. We have studied comments carefully and made corrections which we hope meet with approval. Revised portions are marked in red in the revised manuscript accordingly. Please keep the authors informed if there is any further action needed. The main corrections in the paper and the responds to the reviewer’s comments are as flowing:

------------------------------------------------------------------------------------------------------------------------------

REVIEWER 4:

Good research topic and relevant to the journal theme. Adequate data collection. Perhaps correlation between different properties would be useful. Comments include:

 

1) – HGY is it the right acronym.

Response: Thank you for your comment. To better represent the abbreviation of granite mechanism sand, the initials of granite are used as abbreviations.

 

2) – Page 2.What is meant by the first sentence of the second paragraph.

Response: Thank you for your comment. Based on the primary particle size range of river sand, the particles within the manufactured sand (MS) with a particle size ranging from 0.075 mm to 2.36 mm are defined as the effective sand of the MS. The ratio of the mass of the effective sand to the total mass of the MS is referred to as the effective sand content.

However, the expression in this paragraph is not correct. This paragraph wants to explain the influence of fine aggregate on the performance of concrete. Therefore, we have modified the paragraph accordingly, as follows:

In addition, an appropriate fine sand content helps to enhance the bonding force be-tween the cement paste and aggregates, strengthening the overall wear resistance. If the fi-ne sand content is too high, a large amount of fine sand will adsorb the cement paste，which may lead to uneven distribution of the cement paste. Some aggregate surfaces cannot be fully coated, resulting in weak bonding. On the other hand, if the fine sand content is too low, the contact area between the coarse aggregates and the cement paste is limited, and it is also difficult to form a high-strength bond. During the wear process, the aggregates can easily break away from the cement matrix, causing potholes, spalling and other diseases on the pavement surface, and the wear resistance will decline sharply.

 

 

3) – IMPROVE THE SENTENCE…Nanning local tap water is used for drinking water, which meets the ' Standards for drinking water quality ' (GB5749-2006) 21.

Response: Thank you for your comment. According to your suggestion, we have modified it. The modified content is as follows:

The water used in this study is the local tap water in Nanning. The water has been strictly tested and meets the requirements of the ' Standards for drinking water quality ' (GB5749-2006) [30]. The water quality is safe and reliable and can meet the water demand of this study.

 

4) – Table 9. what is the difference between adjusted sand and effective sand. Where is the stone powder or is it in Table 10.

Response: Thank you for your comment. The technical indexes of stone powder are in table 6, and the mix proportion of stone powder concrete is in table 10. Difference between Adjusted Sand and Effective Sand:

 

 

Adjusted sand:

The particle size range is 2.36 - 4.75 mm. These sand particles are relatively large and primarily serve as a framework in concrete, providing structural support and contributing to the strength and stability of the concrete. Due to their larger particle size, the inter-particle voids are relatively large, which can affect the density of the concrete. However, this can be improved by combining them with sand of other particle sizes.

Effective Sand:

The particle size range is 0.075 - 2.36 mm. These sand particles are smaller in size and can fill the voids between the adjustment sand particles, making the concrete denser. The presence of effective sand can improve the workability of the concrete, such as increasing its fluidity, because smaller sand particles can reduce the internal frictional resistance of the concrete. Moreover, effective sand also plays an important role in the development of concrete strength. It can better disperse cement particles, thereby improving the hydration degree of cement and consequently enhancing the mechanical properties of the concrete.

 

 

5) – Equation 1..abrasion area of specimen…not fully described.

Response: Thank you for your comment. According to your suggestion, we have improved the wear area of the specimen, as follows:

S——Abrasion area of specimen（m²）, the cube specimen takes 0.00766 m².

 

6) – Caption of figure 6. Lithology??..type??

Response: Thank you for your comment. In our study, the primary focus is on the physical and chemical properties of granite manufactured sand, which directly affect the performance of concrete. The term “lithology” can more comprehensively cover key factors such as the mineral composition, particle size distribution, structure, and texture of the rock, all of which are important parameters in determining the performance of manufactured sand. In contrast, “rock type” is more often used for the macro - classification of rocks and cannot provide the detailed information required for our research. Therefore, we have chosen “lithology” as a more accurate descriptive term.

 

 

 

SUMMARY

According to the reviewers’ comments, we tried our best to revise the manuscript. And the revised portions are marked in red in the revised manuscript accordingly.

We appreciate the above advice of the reviewers very much. The advice will greatly benefit for the improvement of the paper and our future research. We appreciate for Editors/Reviewers’ warm work earnestly, and hope that the correction will meet with approvals of the journal.

Your good advice was very much appreciated.

Once again, thank you very much for your comments and suggestions.

Thank you and best regards.

Yours sincerely,

Yuanfeng Chen

 

Corresponding author:

Yuanfeng Chen

Email: 2210391014@st.gxu.edu.cn

 

 

 

 

 

Author Response File: Author Response.pdf

Round 2

Reviewer 2 Report

Comments and Suggestions for Authors

The authors have carefully addressed all the remarks and suggestions provided in the initial review. The manuscript has been significantly improved in terms of scientific clarity, methodological transparency, and overall presentation. The experimental data are now more clearly linked to the conclusions, and the quality of the figures and textual descriptions has been enhanced. Based on the revisions made, the manuscript is now suitable for publication in its current form.

Reviewer 3 Report

Comments and Suggestions for Authors

The authors have addressed the comments/recommendations given by the reviewers, therefore this manuscript is in good shape to be considered for publication in Coatings. Thank you.

Comments on the Quality of English Language

The English usage could be improved better.