Effect of Recycled Foundry Sand on the Workability and Mechanical Properties of Mortar

Round 1

Reviewer 1 Report

1.       In section 3.6, it is suggested to use microstructure to analyze the impact mechanism of W/C ratio and replacement ratio on the workability and mechanical properties of mortar.

2.       Since many groups of experiments have been finished, it is suggested to propose the optimized combination of W/C ratio and replacement ratio for mortar that can be applied in practice according to these experimental results.

Author Response

Answers to comments have been made in the attached file

Author Response File: Author Response.docx

Reviewer 2 Report

This manuscript explores the “Effect of recycled foundry sand on the workability and mechanical properties of mortar”. The manuscript is elaborately described and contextualized with the help of previous and present theoretical background. All the references cited are relevant to this area of research. The methods/analytical study are clearly stated. The result and discussion section are clearly presented. The manuscript needs the following modifications before the acceptance.

1. Abstract – Mention your research recommendation.

2. Abstract: Present more results of your work specifically

3. Key words: Change the foundry sand to Used foundry sand (UFS)

4.  Mention your problem statement clearly.

5. Is the properties of foundry sand in Table 3 tested by the author?

6. State the reason clearly for the reduction in workability, strength, durability of mortar with higher replacement of foundry sand

7. Fig.17. Mark the salient features in SEM image and explain

8. Fig 17. It would be better if magnification is in the rabge of 500x

9. Conclusion: Mention the research recommendations and scope for the future work

Author Response

Answers to comments have been made in the attached file

Author Response File: Author Response.docx

Reviewer 3 Report

The paper is systematic presentation for reusing the waste foundry sand in a cementitious mortar. It was accepted in that form.

Author Response

Answers to comments have been made in the attached file

Author Response File: Author Response.docx

Reviewer 4 Report

In this research, 32 mix proportions were manufactured to study the effect of the foundry sand replacement (FSR) and the water cement ratio (W/C) on the workability physical and mechanical properties, durability, and microstructural characteristics of mortars. The work is realy well organized, well structured, linear, result are well presented and clear. I have no more comments. My best compliments.

Author Response

Answers to comments have been made in the attached file

Author Response File: Author Response.docx

Reviewer 5 Report

The authors used recycled foundry sand in mortar. The paper is generally good but it needs improvement. Followings should be carried out before acceptance:

The abstract should contain important results of the study.

How this recycled materials for this study is obtained?

What is chemical properties of cement

Novelty is not clear. Very same studies are already exists. What is the difference?

The reason for selecting design mixture should be added.

Compare your results with existing studies

Other types of recycled materials can also be used as replacement for aggregate such as glass, marble, steel,PET and coal bvottom ash. The authors should add a brief introduction for the use of recylced materials, types, its improtance for this. For this purpose the following studies also must be add:  investigation of the physical-mechanical properties and durability of high-strength concrete with recycled pet as a partial replacement for fine aggregates; effects of waste powder, fine and coarse marble agregates on concrete compressive strength.; use of recycled coal bottom ash in reinforced concrete beams as replacement for aggregate; concrete containing waste glass as an environmentally friendly aggregate: a review on fresh and mechanical characteristics; mechanical behavior of crushed waste glass as replacement of aggregates;flexural behavior of reinforced concrete beams using waste marble powder towards application of sustainable concrete;  introduction using:  improvement in bending performance of reinforced concrete beams produced with waste lathe scraps; performance assessment of fiber-reinforced concrete produced with waste lathe fibers; performance evaluation of fiber-reinforced concretes produced with steel fibers extracted from waste tire; investigation on improvement in shear performance of reinforced-concrete beams produced with recycled steel wires from waste tires;

Add photos for test setup?

Add photos for utilized materials. There is no photo related to which materials are utilized.

Please add damaged photos damaged photos of samples

The number of reference is too low for this kind of study. Add recent studies on this subject to introduction. There are many studies on the introduction for this topic.

Quality of figures should be increased

Conclusion should be improved. The recommendation consdiering all test should be given for engineers.

Author Response

Answers to comments have been made in the attached file

Author Response File: Author Response.docx

Reviewer 6 Report

The author explored the recycled foundry sand on the workability and mechanical properties of mortar; the topic is fascinating, and the scope is suitable for the journal. However, there are some problems in this paper's writing and experimental analysis, and it is recommended after major revision to reconsider.

Abstract: In lines 23-24, please give specific research conclusions and explain the significance of the research.

Line 47-48, it is recommended to add some introduction. To reuse solid waste and reduce carbon dioxide emissions, the building materials industry has also made great efforts, including the following aspects, such as waste reuse, the use of low-carbon cement-based composite materials, and improving the service life of building materials. These two kinds of literature can be referred to (https://doi.org/10.1016/j.jobe.2022.104880,https://doi.org/10.1016/j.jobe.2023.106018); therefore, as we carry out this research work, the benefits to the environment and society must be elaborated.

For Fig.3a，what is the role of the fitting equation, and its meaning needs to be explained in the article?

For Fig.3b，what valuable information can we get from fig; please explain; fig. 5 also needs to be explained.

For Fig.11.12.13, Please replace it with a clearer Fig.

For, Fig.13b, What is the role of the fitting equation, and its meaning needs to be explained in the article?

For SEM, Details need to be marked on the SEM.

For conclusion part, looking forward to the application value of this research work is necessary.

Line 74-78, elaborate on why you want to study this research. What is the value of this work?please refer to this literature. https://doi.org/10.1016/j.conbuildmat.2022.126921

The novel elements should be clearly described in the Introduction.

In lines 117-119, what equipment is used for the wear resistance test? How are the mortar specimens handled?

In lines 121-122, a reference to the "Pearson correlation coefficient" should be added there.

In lines 131-133, the authors metallized the specimens. How to metalize the specimens? Why is it necessary to metallize the specimens?

Figure 3a should give a top view similar to Figure 3b, and the diameter should be measured with a ruler. Otherwise, no comparison can be made between the two figures, and the conclusion of "Lines 147-149" in the text cannot be drawn.

Figure 4a is not clear and needs to be redrawn. The same problem also occurs in Figures 6a, 7a, 8a, 9-12, 13a and 16.

In Figure 16, how was the value of the variable correlation coefficient obtained? The relevant formula should be given.

The author may refer to and cite the following related articles as well.

 

 Embedded PZT aggregates for monitoring crack growth and predicting surface crack in reinforced concrete beam, Constr. Build. Mater. 364 (2023) 129979, 10.1016/j.conbuildmat.2022.129979.

Author Response

Answers to comments have been made in the attached file

Author Response File: Author Response.docx

Round 2

Reviewer 5 Report

Thank you for improvement

The paper can be accepted.

Author Response

Responses to the reviewers’ comments to the manuscript applsci-2219457

 

Effect of recycled foundry sand on the workability and mechanical properties of mortar

Dear editor,

We greatly appreciate the opportunity you gave us to improve the paper with the valuable comments of the reviewers.

Below you can find the detailed answers to the comments and resulting modifications.

Best regards,

The authors

Author Response File: Author Response.docx

Reviewer 6 Report

The author has replied to all the comments made by the reviewers, but there are a few replies that are not satisfactory. In addition, the author has made a mistake in the reviewer's number. It is recommended that the author revise carefully and consider it after major revision.

1.      For Fig.3a，what is the role of the fitting equation, and its meaning needs to be explained in the article? Is this fitting equation universal and can it be extended?

2.      For, Fig.13b, What is the role of the fitting equation, and its meaning needs to be explained in the article? Is this fitting equation universal and can it be extended?

3.      For SEM, Details need to be marked on the SEM. Specific substances need to be marked, please add it.

4.      Line 74-78, elaborate on why you want to study this research. What is the value of this work?please refer to this literature. https://doi.org/10.1016/j.conbuildmat.2022.126921. The references cited by the author are not related to low carbon, it is recommended to refer to the references recommended by the reviewers.

 

5.      The novel elements should be clearly described in the Introduction. It is not that no one studies or few studies are innovations, and the significance and importance of its research need to be explained.

Author Response

Responses to the reviewers’ comments to the manuscript applsci-2219457

 

Effect of recycled foundry sand on the workability and mechanical properties of mortar

Dear editor,

We greatly appreciate the opportunity you gave us to improve the paper with the valuable comments of the reviewers.

Below you can find the detailed answers to the comments and resulting modifications.

Best regards,

The authors

 

----

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Reviewer 6 (changes in red).

The author has replied to all the comments made by the reviewers, but there are a few replies that are not satisfactory. In addition, the author has made a mistake in the reviewer's number. It is recommended that the author revise carefully and consider it after major revision.

Dear reviewer, in the applied science web page your reviewer number is 6, the authors apologize for the confusion, in advance we thank you for the comments in order to enhance the manuscript.

1. For Fig.3a，what is the role of the fitting equation, and its meaning needs to be explained in the article? Is this fitting equation universal and can it be extended?

Dear reviewer, thank you for this comment, the following paragraph has been added in lines 177 to 180:

The fitting equations for each UFS replacement percentage show that in general there is a linear relationship between increasing W/C ratio and slump. If the methodology is replicated in another study, validated results can be guaranteed for each replacement percentage.

2. For, Fig.13b, What is the role of the fitting equation, and its meaning needs to be explained in the article? Is this fitting equation universal and can it be extended?

Dear reviewer, thank you for this comment, the following paragraph has been added in lines 308 to 312:

The fitting equations for each UFS replacement percentage show the relationship between increasing W/C ratio and decreasing compressive strengths. It is observed that a small variation in the W/C ratio has a major influence on the compressive strength when higher percentages of UFS are used. Also, it is observed that the slope increases with increasing UFS

3. For SEM, Details need to be marked on the SEM. Specific substances need to be marked, please add it.

Dear reviewer, in this regard the details in the SEM images have been marked as it shows:

UFS =0%	UFS =25%
(a)	(b)
UFS =50%	UFS =75%
(c)	(d)
UFS =100%
(e)

Microstructural analysis under 25x magnification: Pores, cracks and cabities of UFS mortars with 0%(a), 25% (b), 50%(c), 75% (d) and 100% (e) substitution.

 

 

UFS =0%	UFS =25%
(a)	(b)
UFS =50%	UFS =75%
(c)	(d)
UFS =100%
(e)

 

Microstructural analysis under 500x magnification. Bond between paste and aggregates of UFS mortars with 0%(a), 25% (b), 50%(c), 75% (d) and 100% (e) substitution.

4. Line 74-78, elaborate on why you want to study this research. What is the value of this work? please refer to this literature. https://doi.org/10.1016/j.conbuildmat.2022.126921. The references cited by the author are not related to low carbon, it is recommended to refer to the references recommended by the reviewers.

Dear reviewer, thanks for your comment, regarding the value of this work, the following has been added in lines 93 to 96:

The value of this research lies in the study of the physical-mechanical properties and statistical analysis of the effects of incorporation of UFS in mortar to achieve more sustainable materials, following the research line of low carbon footprint materials as other authors have developed [32]. 

[32] Cui, K.; Liang, K.; Chang, J.; Lau, D. Investigation of the Macro Performance, Mechanism, and Durability of Multiscale Steel Fiber Reinforced Low-Carbon Ecological UHPC. Constr. Build. Mater. 2022, 327, 126921, doi:10.1016/j.conbuildmat.2022.126921.

5. The novel elements should be clearly described in the Introduction. It is not that no one studies or few studies are innovations, and the significance and importance of its research need to be explained.

Dear reviewer, in this regard, the following lines have been added in lines 96 to 100:

Most studies use low UFS replacements and a fixed W/C ratio. This paper investigates in depth the influence between higher UFS replacements and W/C ratio. Also, the mechanical durability will be analysed. The total use of UFS as an aggregate in mortars is an alternative to avoid the exploitation of natural resources and in-crease the life cycle of a material that is perceived as waste.

Author Response File: Author Response.docx

Round 3

Reviewer 6 Report

The author carefully revised the reviewers' comments, and the article's quality has been greatly improved. It is recommended to accept this manuscript.