Rheological Properties of Cement Paste Containing Ground Fly Ash Based on Particle Morphology Analysis

Round 1

Reviewer 1 Report

The theoretical, experimental background and aim of the study are suitable for the special issue. However, the authors should mention why their applied method could be useful and important for green building materials and structural performance. Furthermore, the authors should provide more detailed discussions correlating their data with the results of the previous studies on the influence of fly ash admixtures on the rheological properties of cement. The current format is more or less a technical report instead of a research article. I added some corrections and suggestions in the revised MS. Overall, I could advise moderate corrections, and would like to re-consider the MS after suggested corrections made by the authors.

Comments for author File: Comments.pdf

Author Response

Thank you for your hard work and recognition of this paper. Those comments are very helpful for revising and improving our paper. We have studied the comments carefully and made corrections which we hope meet with approval. 

In the revised manuscript, we have added the importance of this study in the abstract and introduction.
In the abstract, we have rewrite the background:"Separating finer particles from raw fly ash is a popular method to produce high-performance admixture of concrete. However, the supply of separated fly ash is obviously behind the demand and the residue fly ash is difficult to be disposed. Ground fly ash is another method to improve the particle size and reactivity, but the change of particle morphology during grinding may affect the rheological properties of cement paste and concrete, which limited the application of ground fly ash in concrete project."
In the introduction, we added that "The rheological properties of fresh concrete containing ground fly ash is significant in the construction process, while the influence law and mechanism is not clear up to now."
The changes have been highlighted in red color.

In the discussion section, we have moved the particle morpology analysis to the discussion on the basis of another reviewer's suggestion. In the particle morphology analysis, shear rate and apparent viscosity analysis, rheological parameter analysis, packing density analysis and zeta potential analysis, we have used the discussions of some related bibliographical references to support the discussion of our results. These references have ever given some related experiment and conclusion, and our experiments continued the further studies. The references and related analysis are listed in the section, and the changes have been highlighted in red color.

The corrections and suggestions in the pdf are also revised and answered. Thank you for your suggestion again.

Author Response File: Author Response.pdf

Reviewer 2 Report

Dear author,
Please consider the following remarks.
1. Line 34. It is recommended to refer not to normative documents but the underlying scientific results.
2. Line 34 and others. Standards and regulatory documents should be described so that a foreign language reader can understand them. References to local standards are incomprehensible to English-speaking readers and without detailed explanations. Links to the full texts of the standards should be added. It is recommended to refer not to normative documents but the underlying scientific results.
3. Lines 78-82. A more detailed description of the measuring equipment is required.
4. References are not formatted correctly. DOI or URL are missing. Use free Mendeley reference manager (or similar software) is recommended. Use MDPI citation style, available for installing to Mendeley software with entering the link http://www.zotero.org/styles/multidisciplinary-digital-publishing-institute.

Author Response

Thank you for your hard work and recognition of this paper. Those comments are very helpful for revising and improving our paper. We have studied the comments carefully and made corrections which we hope meet with approval. The main corrections are in the manuscript and the responds to the reviewers’ comments are as follows.

1. Line 34. It is recommended to refer not to normative documents but the underlying scientific results.
Reply：The conclusion is from scientific results, not from normative documents. Our original intention is to solve the problem in the application of low-grade fly ash, and the difference between high-grade and low-grade fly ash was listed in the original paper. The changes have been highlighted in red color.

2. Line 34 and others. Standards and regulatory documents should be described so that a foreign language reader can understand them. References to local standards are incomprehensible to English-speaking readers and without detailed explanations. Links to the full texts of the standards should be added. It is recommended to refer not to normative documents but the underlying scientific results.
Reply: The standard in Line 34 has been deleted, and the "fly ash of grade I" is substituted by "the high-grade fly ash". In Line 73, it is the reference of the experiment method. The link of this standard is added in the reference, and has been highlighted in red color.

3. Lines 78-82. A more detailed description of the measuring equipment is required.
Reply: More details of SEM are added in the paper, and the magnification is added. The additions have beedn highlighted in red color.

4. References are not formatted correctly. DOI or URL are missing. Use free Mendeley reference manager (or similar software) is recommended. Use MDPI citation style, available for installing to Mendeley software with entering the link http://www.zotero.org/styles/multidisciplinary-digital-publishing-institute.
Reply:  Thank you for your suggestion. We are trying to use Mendeley here and the reference are rewrote. 

Reviewer 3 Report

Journal: Crystals (ISSN 2073-4352)

Manuscript ID: crystals-1647175

Type: Article

Title: Rheological properties of cement paste containing ground fly ash based on particle morphology analysis

Authors: Juntao Ma, Huifang Zhang, Daguang Wang, Huixian Wang, Gonglian Chen

Section: Inorganic Crystalline Materials

Special Issue: Advances in Green Building Materials and Structural Performances

General comments for authors:

The title of the paper is interesting despite the fact that there is a vast amount of work in this field.

Specific comments form authors:

Abstract:

-The Abstract needs to be rewritten. The authors do not state the main objective of this work. This is essential. Check.

-The first paragraph (lines 11 and 12) is poorly written and confusing. Check.

-The analytical methods used in the research are not mentioned. Check.

-There are confusing terms such as: "separated fly ash", "zata potential". Check.

Authors are recommended to rewrite the Abstract according to the following steps: a very short introduction; a clear statement of the objective of the work; methods used; and a concluding paragraph saying what the results obtained would be useful for and in which field they could be used. Check.

Line 27. Fly ash is not a mineral. Please check.

Bibliographic references in brackets [1-3], [4-8]... should not be represented as superscript, they have to be in line with the text. Please arrange throughout the text.

Section 2. Change the word "Experiment" to "Materials and methods". Check.

Subsection 2.1. Change the phrase "Fly ash treatment and analysis" to "Materials". Check.

Figure 1. The resolution of Figure 1 is poor. Please improve it.

Figures 1, 2 and 3 as well as Tables 2 and 3 have to be removed to the "Results" Section. Furthermore, in the Subsection "Methods", the authors have to explain in detail the procedure to determine the pore distribution and the analysis by SEM. Check.

Subsection 2.2. Change the phrase "Experiment design" to "Methods". Check.

Subsection 3. Change the phrase "Experimental results and analysis" to "Results and discussion". Check.

Figures 4, 5, 6, 7, 8 and 9 have poor resolution and need to be improved. Check.

The authors do not make any bibliographic reference in the "Results and discussion" section, so their results are not contrasted; thus, their arguments are inconsistent. It is recommended that the authors introduce several bibliographical references to contrast their work. Check.

The "Discussion" section is missing. The authors limit themselves only to presenting the results, but do not make a discussion supported by bibliographical citations; this turns the work into a mere technical report. Check.

Conclusions: The authors have forgotten to write down possible applications of the results obtained. Check.

Author Response

Thank you for your hard work and recognition of this paper. Those comments are very helpful for revising and improving our paper. We have studied the comments carefully and made corrections which we hope meet with approval. The main corrections are in the manuscript and the responds to the reviewers’ comments are as follows.

-The Abstract needs to be rewritten. The authors do not state the main objective of this work. This is essential. Check.
Reply:  The main objective of this work is to study if ground fly ash can substitute seperated fly ash in concrete. The seperated fly ash is popular and effective, but the supply of separated fly ash is obviously behind the demand and the residue fly ash is difficult to be disposed. Grinding process is useful to improve the particle size and reactivity, but the particle morphology may affect the rheological properties. This experiment is to study the difference of seperated fly ash and ground fly ash in rheological test of cement paste. It is very significant to the application of ground fly ash. The revised abstract is highlighted in red color in the manuscript.

-The first paragraph (lines 11 and 12) is poorly written and confusing. Check.
Reply:  The objective of this study is rewrited and the original sentence has been deleted. The revised abstract is highlighted in red color in the manuscript.

-The analytical methods used in the research are not mentioned. Check.
Reply: The particle morphology is analyzed by Image-Pro Plus process and spherical particles proportion calculation, and the following rheological study is based on this. This part is added in the abstract and highlighted in red color in the manuscript.

-There are confusing terms such as: "separated fly ash", "zata potential". Check.
Reply: Separated fly ash is to describe the finer particles in raw fly ash, which are seperated by the pneumatic separation system. I am sorry that I have not found a properer phrase to describe it. "zata potential" is a clerical error and has been revised in the abstract. The revised abstract is highlighted in red color in the manuscript.

Authors are recommended to rewrite the Abstract according to the following steps: a very short introduction; a clear statement of the objective of the work; methods used; and a concluding paragraph saying what the results obtained would be useful for and in which field they could be used. Check.
Reply: Thank you for your recommendation here. I have rewrited the abstract on the basis of your recommendation. The revised abstract is highlighted in red color in the manuscript.

Line 27. Fly ash is not a mineral. Please check.
Reply: "mineral admixture" has been revised to "supplementary cementing material". The changes have been highlighted in red color.

Bibliographic references in brackets [1-3], [4-8]... should not be represented as superscript, they have to be in line with the text. Please arrange throughout the text.
Reply: All the superscripts are revised in the manuscript. We use the Mendeley to rewrite the references. In the revised manuscript, all the references are formatted correctly.

Section 2. Change the word "Experiment" to "Materials and methods". Check.
Reply: Thank you for your suggestion. The word "Experiment" has been changed to "Materials and methods". The changes have been highlighted in red color.

Subsection 2.1. Change the phrase "Fly ash treatment and analysis" to "Materials". Check.
Reply: Thank you for your suggestion. The phrase "Fly ash treatment and analysis" has been changed to "Materials". The changes have been highlighted in red color.

Figure 1. The resolution of Figure 1 is poor. Please improve it.
Reply：Figure 1 has been exported from the software again, and the figure is replaced and improved.

Figures 1, 2 and 3 as well as Tables 2 and 3 have to be removed to the "Results" Section. Furthermore, in the Subsection "Methods", the authors have to explain in detail the procedure to determine the pore distribution and the analysis by SEM. Check.
Reply: Figures 1, 2 and 3 as well as Tables 2 and 3 have been removed to the "Results" Section. And the related introduction is revised.  The changes have been highlighted in red color.

Subsection 2.2. Change the phrase "Experiment design" to "Methods". Check.
Reply: Thank you for your suggestion. The phrase "Experiment design" has been changed to "Methods". The changes have been highlighted in red color.

Subsection 3. Change the phrase "Experimental results and analysis" to "Results and discussion". Check.
Reply: Thank you for your suggestion. The phrase "Experimental results and analysis" has been changed to "Results and discussion". The changes have been highlighted in red color.

Figures 4, 5, 6, 7, 8 and 9 have poor resolution and need to be improved. Check.
Reply: Figures 4, 5, 6, 7, 8 and 9 have been improved and replaced in the manuscript.

The authors do not make any bibliographic reference in the "Results and discussion" section, so their results are not contrasted; thus, their arguments are inconsistent. It is recommended that the authors introduce several bibliographical references to contrast their work. Check.
Reply: Thank you for your suggestion. To support the discussion of the results, we have used the discussions of some related bibliographical references in the "Results and discussion" section. These references have ever given some related experiment and conclusion, and our experiments continued the further studies. The references and related analysis are listed in the section, and the changes have been highlighted in red color. Thank you for your suggestion again.

The "Discussion" section is missing. The authors limit themselves only to presenting the results, but do not make a discussion supported by bibliographical citations; this turns the work into a mere technical report. Check.
Reply: Thank you for your suggestion. We have added some mechanism analysis on the basis of some related references. The changes have been highlighted in red color.

Conclusions: The authors have forgotten to write down possible applications of the results obtained. Check.
Reply: In the conclusion, we have added "When the addition of ground fly ash exceeds 30%, extra adjustment methods are needed to improve the rheological properties of cement paste." It is valuable when ground fly ash is applied in concrete. The changes have been highlighted in red color.

Round 2

Reviewer 1 Report

The authors did almost all suggested corrections. I do not have any further scientific comment; however, some typo errors still exist and some parts of the MS should be re-phrased by the authors, especially in section 3.4. After these corrections done, the MS could send to production service.

Comments for author File: Comments.pdf

Author Response

Thank you for your every comments of this paper. The typo errors have been rewriten. This paper has been greatly improved by your advice.

Author Response File: Author Response.docx

Reviewer 3 Report

The authors have answered all the questions raised. The work has undergone a visible improvement.

Author Response

Thank you for your hard work and recognition of this paper.