The Performance of Alkali-Activated Self-Compacting Concrete with and without Nano-Alumina

Round 1

Reviewer 1 Report

The authors have submitted a well prepared paper on the interesting topic of the Effect of Nanoalumina on the Characterization of Sustainable Alkali-Activated Self-Compacting Concrete. The highlights in this study, the effect of nano-alumina (NA) on the fresh and hardened stag of Fly ash (FA) and/or slag (S)-based alkali-activated self-compacting concrete cured at an ambient environment was investigated. The paper is clearly presented and provides interesting results. This study is valuable for the practical engineering. However, the following comments are provided to assist the authors to improve the paper:

1) The article's purpose should be clarified in detail, why this study could be beneficial, and a more in-depth conclusion in applications should be provided.

2) Kindly provide the images of fly ash (FA) and slag (S) used in the present study.

3) Why was the alkali-activated solution ratio to binder materials kept constant as 0.5? The author should have references and explanations.

4) How many days does the curing time before the compressive strength test, splitting tensile strength test and flexural strength test? Please describe.

5) Figure 1 to Figure 7 have low pixels and should be improved clearly.

6) The sample considered for this study needs to be more convincing. What is the standard deviation and COV value considered?

7) I recommend expanding to ref [5] the following articles related to geopolymer materials; doi.org/10.3390/su14169856; doi.org/10.21660/2018.42.7152.

8) Conclusions: the author should further explain this research's construction application limitations. Please describe in the conclusion.

Author Response

Response to Reviewer 1 Comments

• The authors have submitted a well-prepared paper on the interesting topic of the Effect of Nanoalumina on the Characterization of Sustainable Alkali-Activated Self-Compacting Concrete. The highlights in this study, the effect of nano-alumina (NA) on the fresh and hardened stag of Fly ash (FA) and/or slag (S)-based alkali-activated self-compacting concrete cured at an ambient environment was investigated. The paper is clearly presented and provides interesting results. This study is valuable for the practical engineering. However, the following comments are provided to assist the authors to improve the paper:

Response 1: Thank you indeed for your valuable comments.

 

• The article's purpose should be clarified in detail, why this study could be beneficial, and a more in-depth conclusion in applications should be provided.

Response 2: Agree, The revised manuscript was revised and rephrased and the purpose of the paper was added with many conclusions.

 

• Kindly provide the images of fly ash (FA) and slag (S) used in the present study.

Response 3: Agree, the images of fly ash (FA) and slag (S) and materials used in the present study were added to the revised manuscript.

 

• Why was the alkali-activated solution ratio to binder materials kept constant at 0.5? The author should have references and explanations.

Response 4: Agree, as mentioned in the previous research, that the optimum ratio of alkali-activated solution ratio to binder materials is 0.5. However, this ratio was fixed constant for all mixes.

 

• How many days does the curing time before the compressive strength test, splitting tensile strength test, and flexural strength test? Please describe.

Response 5: Agree, the curing time was added to the revised manuscript.

 

• Figures 1 to Figure 7 has low pixels and should be improved clearly.

Response 4: Agree, the figures were improved in the revised manuscript.

 

• The sample considered for this study needs to be more convincing. What is the standard deviation and COV value considered?.

Response 5:  Agree, the standard deviation was added to the revised manuscript.

 

• I recommend expanding to ref [5] The following articles related to geopolymer materials; doi.org/10.3390/su14169856; doi.org/10.21660/2018.42.7152

Response 4: Agree, the above reference was cited in the revised manuscript.

 

• Conclusions: the author should further explain this research's construction application limitations. Please describe in the conclusion

Response 5: Agree, the conclusion section was revised with further explanations.

Author Response File: Author Response.pdf

Reviewer 2 Report

Dear author(s),

there are some inspiring insights thorough the manuscript and I tend to agree on its publication. However, there are few points that needs to be quickly addressed to improve its overall communication:

 

Title:

1/ be more specific about the "Effect", clearly condensate the novelty and significance of the main discovery into a short and groundbreaking claim

 

Abstract:

2/ strictly follow the established schema of writing academic Abstract: A/ introduction (urgency and significance of the research hypothesis); B/ principles of the methods used + key results; C/ conclusions (commercial and environmental impacts)

3/ reduce the use of abbreviations, jargon and technical terms, please understand that the purpose of the Abstract is to explain to all readers (including those from other disciplines) what the paper is about

4/ there is no reason to go into detail and present the results obtained under specific reaction conditions, rather provide a synthesis of the results obtained

5/ originality and significance needs to be better communicated

 

Introdustion:

6/ use only SI units if you want to get published in international journal (avoid "BTU", "pounds" etc.)

7/ the "pollution crisis" needs to be better put into the context, refer to paper "Techno-economic review on short-term anthropogenic emissions of air pollutants and particulate matter"

8/ go straight to the point and more in depth, write more technically (always provide corresponding numbers), significantly condensate all the text by reducing ballast phrases and cliché

9/ make sure that this chapter fully introduces any reader into to the topic, explain all the terms, units, abbreviations, Latin and Greek letters, and the whole context that is necessary for anyone (including experts from other disciplines) to understand the following chapters

10/ with regards to "carbon dioxide", you should remind our readers with the most profitable methods of carbon sequestration that can be achieved in synergy with nutrient regeneration ("Economic considerations on nutrient utilization in wastewater management")

11/ the importance of pricing of metals should be commented, provide numbers

12/ please understand that if you use any currency, you must also add the corresponding date so that exchange rates and in(de)flation can be calculated, refer to paper "The Influence of the International Price of Oil on the Value of the EUR/USD Exchange Rate"

13/ the research hypothesis is hard to find, make sure the urgency and significance of its investigation was properly justified

 

Experimental methods:

14/ the method must be presented in such a way that it can be reproduced anytime, by anyone, anywhere (do not create obstacles like referring to specific location etc.)

15/ avoid overkill of zeros, "100000" = 0.1 M

16/ please understand that the methodology must be described in a completely unambiguous way that does not allow for multiple interpretations (everyone who reads this chapter should get very precise instructions on how to repeat your procedure to achieve exactly the same results)

17/ Table 1 and Table 2 seems to represent some results of yours, if so - move it into the chapter "Results and Discussions"

18/ each material/reactant and apparatus used needs to be presented in detail (serial number, setup, process parameters, manufacturer, country of origin, purity etc.)

19/ provide cost breakdown or at least some simplified financial analysis if you are about to argue that this concept is realistic (refer to latest papers on manufacturing "Sustainable Organizational Performance, Cyber-Physical Production Networks, and Deep Learning-assisted Smart Process Planning in Industry 4.0-based Manufacturing Systems" and "Artificial Intelligence Data-driven Internet of Things Systems, Real-Time Advanced Analytics, and Cyber-Physical Production Networks in Sustainable Smart Manufacturing")

 

Results and Discussions:

20/ change the chapter title to "Results and Discussions"

21/ each Tab. and Fig. should be provided with caption that describes A/ what can be seen and B/ how is this relevant to the research hypothesis

22/ show more self-criticism to your work (can all the methods and results be fully trusted? what are the weaknesses of the methods used? where do the main measurement inaccuracies arise? what are the limitations from a commercial point of view? are the lessons learned transferable to other fields?), comment the latest findings in concrete production, refer to paper "Shower cooler reduces pollutants release in production of competitive cement substitute at low cost"

23/ avoid data overkill, present only the most most industrially important results (focus on financial analysis)

24/ pricing of metals is crucial for this manuscript, refer to papers "Predicted Future Development of Imperfect Complementary Goods – Copper and Zinc Until 2030", "Development of copper price from July 1959 and predicted development till the end of year 2022", "Copper and Aluminium as Economically Imperfect Substitutes, Production and Price Development"  and "Silver as a value keeper and wealth distributor during an economic recession"

25/ propose some improvements and direction for future research

26/ discuss the latest findings on "alumina", refer to papers "Aluminum nanoparticles from liquid packaging board improve the competitiveness of (bio) diesel"

27/ Fig. 1: do not use weird abbreviations such as "100S-0,5NA" etc., use A, B - G instead

28/ the energy-circularity nexus needs do be discussed deeper, refer to papers "Clusters in Transition to Circular Economy: Evaluation of Relation" and "A Comprehensive Bibliometric Analysis of the Energy Poverty Literature: From 1942 to 2020"

29/ compare your results in more depth with the existing literature, identify the main deviations and try to explain the mechanisms by which they may have been caused

30/ the economic point of view should not be ignored, refer to papers "Does the life cycle affect earnings management and bankruptcy?" and "Data-driven Machine Learning and Neural Network Algorithms in the Retailing Environment: Consumer Engagement, Experience, and Purchase Behaviors"

31/ reveal the main driving mechanisms of your results, provide deeper synthesis and reveal some more original/significant findings

 

Conclusions:
32/ do not repeat your methods and results again and again, please understand that the Conclusion chapter is not a summary of your work, present only original and industrially significant revelations that have the potential to expand the horizon of human knowledge (higher level of generalization is mandatory)

33/ clearly indicate whether the research hypotheses tends to be confirmed or not

34/ novelty and significance of these revelations needs to be better communicated

Author Response

Response to Reviewer 2 Comments

• there are some inspiring insights thorough the manuscript and I tend to agree on its publication. However, there are few points that needs to be quickly addressed to improve its overall communication:

Response: Thank you indeed for your valuable comments.

 

• Title:

1/ be more specific about the "Effect", clearly condensate the novelty and significance of the main discovery into a short and groundbreaking claim

Response 1: Agree, The title was changed in the revised manuscript.

 

• Abstract:

2/ strictly follow the established schema of writing academic Abstract: A/ introduction (urgency and significance of the research hypothesis); B/ principles of the methods used + key results; C/ conclusions (commercial and environmental impacts).

Response 2: Agree, the abstract section was revised in the revised manuscript.

 

• reduce the use of abbreviations, jargon and technical terms, please understand that the purpose of the Abstract is to explain to all readers (including those from other disciplines) what the paper is about.

Response 3: Agree, the section was revised and the abbreviations were reduced.

 

• there is no reason to go into detail and present the results obtained under specific reaction conditions, rather provide a synthesis of the results obtained.

Response 4: Agree, kindly, the section was revised and explained with short details.

 

• originality and significance needs to be better communicated.

Response 5: Agree, the section was rechecked and revised.

• Introdustion:

6/ use only SI units if you want to get published in international journal (avoid "BTU", "pounds" etc.).

Response 6: Agree, the section was rechecked and revised.

• the "pollution crisis" needs to be better put into the context, refer to paper "Techno-economic review on short-term anthropogenic emissions of air pollutants and particulate matter".

Response 7: Agree, the section was rechecked and revised.

• go straight to the point and more in depth, write more technically (always provide corresponding numbers), significantly condensate all the text by reducing ballast phrases and cliché.

Response 8: Agree, the section was rechecked and revised.

• make sure that this chapter fully introduces any reader into to the topic, explain all the terms, units, abbreviations, Latin and Greek letters, and the whole context that is necessary for anyone (including experts from other disciplines) to understand the following chapters.

Response 9: Agree, the section was rechecked and revised.

• with regards to "carbon dioxide", you should remind our readers with the most profitable methods of carbon sequestration that can be achieved in synergy with nutrient regeneration ("Economic considerations on nutrient utilization in wastewater management").

Response 10: Agree, the section was rechecked and revised.

• the importance of pricing of metals should be commented, provide numbers.

Response 11: Agree, the section was revised and the pricing of metals was added.

• please understand that if you use any currency, you must also add the corresponding date so that exchange rates and in(de)flation can be calculated, refer to paper "The Influence of the International Price of Oil on the Value of the EUR/USD Exchange Rate".

Response 12: Agree, the above paper was mentioned in the revised manuscript.

• the research hypothesis is hard to find, make sure the urgency and significance of its investigation was properly justified.

Response 13: Agree, the revised manuscript was rechecked with more explanation and details.

• Experimental methods:

14/ the method must be presented in such a way that it can be reproduced anytime, by anyone, anywhere (do not create obstacles like referring to specific location etc.).

Response 14: Agree, the revised manuscript was rechecked with more explanation and details.

• avoid overkill of zeros, "100000" = 0.1 M.

Response 15: Agree, the revised manuscript was rechecked and revised.

• please understand that the methodology must be described in a completely unambiguous way that does not allow for multiple interpretations (everyone who reads this chapter should get very precise instructions on how to repeat your procedure to achieve exactly the same results).

Response 16: Agree, the revised manuscript was revised with more details.

• Table 1 and Table 2 seems to represent some results of yours, if so - move it into the chapter "Results and Discussions".

Response 17: Thank you for your valuable comments, Tables 1 and 2 include data from the supplier that provided the materials for the experiments.

• each material/reactant and apparatus used needs to be presented in detail (serial number, setup, process parameters, manufacturer, country of origin, purity etc.).

Response 18: Agree, the revised manuscript was rechecked and revised.

• provide cost breakdown or at least some simplified financial analysis if you are about to argue that this concept is realistic (refer to latest papers on manufacturing "Sustainable Organizational Performance, Cyber-Physical Production Networks, and Deep Learning-assisted Smart Process Planning in Industry 4.0-based Manufacturing Systems" and "Artificial Intelligence Data-driven Internet of Things Systems, Real-Time Advanced Analytics, and Cyber-Physical Production Networks in Sustainable Smart Manufacturing").

Response 19: Thank you indeed for your valuable comments, the authors investigated the performance (fresh and hardened properties) of alkali-activated concrete incorporating nano-alumina.

• Results and Discussions:

20/ change the chapter title to "Results and Discussions".

Response 20: Agree, the title was changed.

• each Tab. and Fig. should be provided with caption that describes A/ what can be seen and B/ how is this relevant to the research hypothesis.

Response 21: Agree, the manuscript was rechecked and revised.

• show more self-criticism to your work (can all the methods and results be fully trusted? what are the weaknesses of the methods used? where do the main measurement inaccuracies arise? what are the limitations from a commercial point of view? are the lessons learned transferable to other fields?), comment the latest findings in concrete production, refer to paper "Shower cooler reduces pollutants release in production of competitive cement substitute at low cost".

Response 22: Agree, the manuscript was rechecked and revised with more details.

• avoid data overkill, present only the most most industrially important results (focus on financial analysis).

Response 23: Agree, the manuscript was rechecked and revised with more details.

• pricing of metals is crucial for this manuscript, refer to papers "Predicted Future Development of Imperfect Complementary Goods – Copper and Zinc Until 2030", "Development of copper price from July 1959 and predicted development till the end of year 2022", "Copper and Aluminium as Economically Imperfect Substitutes, Production and Price Development" and "Silver as a value keeper and wealth distributor during an economic recession".

Response 24: Agree, the pricing of the metals was added to the revised manuscript.

• propose some improvements and direction for future research.

Response 25: Agree, the manuscript was rechecked and revised with more details.

• discuss the latest findings on "alumina", refer to papers "Aluminum nanoparticles from liquid packaging board improve the competitiveness of (bio) diesel".

Response 26: Agree, the manuscript was revised and the above paper was mentioned.

• Fig. 1: do not use weird abbreviations such as "100S-0,5NA" etc., use A, B - G instead.

Response 27: Agree, the figures were improved and the abbreviations were described in the previous section.

• the energy-circularity nexus needs do be discussed deeper, refer to papers "Clusters in Transition to Circular Economy: Evaluation of Relation" and "A Comprehensive Bibliometric Analysis of the Energy Poverty Literature: From 1942 to 2020".

Response 28: Thank you indeed for your valuable comments, the authors investigated the performance (fresh and hardened properties) of alkali-activated concrete incorporating nano-alumina.

• compare your results in more depth with the existing literature, identify the main deviations and try to explain the mechanisms by which they may have been caused.

Response 29: Agree, the manuscript was rechecked and revised with more details.

• the economic point of view should not be ignored, refer to papers "Does the life cycle affect earnings management and bankruptcy?" and "Data-driven Machine Learning and Neural Network Algorithms in the Retailing Environment: Consumer Engagement, Experience, and Purchase Behaviors".

Response 30: Thank you indeed for your valuable comments, the authors investigated the performance (fresh and hardened properties) of alkali-activated concrete incorporating nano-alumina.

• reveal the main driving mechanisms of your results, provide deeper synthesis and reveal some more original/significant findings.

Response 31: Agree, the manuscript was rechecked and revised with more details.

 

• Conclusions:

32/ do not repeat your methods and results again and again, please understand that the Conclusion chapter is not a summary of your work, present only original and industrially significant revelations that have the potential to expand the horizon of human knowledge (higher level of generalization is mandatory)

33/ clearly indicate whether the research hypotheses tends to be confirmed or not

34/ novelty and significance of these revelations needs to be better communicated.

Response 31: Agree, the conclusion section was rechecked and revised with more details.

 

 

 

 

 

 

 

 

 

 

 

 

Author Response File: Author Response.pdf

Reviewer 3 Report

-We live now in a climate emergency so its most strange that the authors have not start the paper by mentioning exactly that. It seems that they are not aware about the words of a Professor of Physics at the University of Oxford authored a paper where one can read the following:

 “Let’s get this on the table right away, without mincing words. With regard to the climate crisis, yes, it’s time to panic”

Pierrehumbert, R., 2019. There is no Plan B for dealing with the climate crisis. Bulletin of the Atomic Scientists, pp.1-7.

So please start the introduction by draw a connection between environmental degradation and resource efficiency.

 

- Remove sustainable from the title and from abstract because no LCA was carried out. Even because sodium silicate and sodium hydroxide have a high carbon footprint. Let´s also no forget that Ouellet-Plamondon and Habert (2014) showed that only ´one part alkali-activated` binders shows carbon footprint levels much lower than Portland cement based mixtures.

Ouellet-Plamondon, C. ; Habert, G. (2014) Life cycle analysis (LCA) of alkali-activated cements and concretes. In Handbook of Alkali-Activated Cements, Mortars and Concretes, 663-686 (Eds) WoodHead Publishing-Elsevier, Cambridge

 

-The authors should read the paper below to have an update about these materials:

Palomo A, Maltseva O, Garcia-Lodeiro I and Fernández-Jiménez A (2021) Portland Versus Alkaline Cement: Continuity or Clean Break: “A Key Decision for Global Sustainability”. Front. Chem. 9:705475. doi: 10.3389/fchem.2021.705475

 

- The first phrase of the abstract must be a summary of the introduction

 

- “significant reductions in both natural resource use and CO2 emissions”

Comment: Where´s the evidence of that ?

 

-”Geopolymer 58 concrete (GPC) is made without the use of heat and emits no CO2

Comment: Remove that phrase because is scientific inacurate

 

Avoid mixing geopolymers with alkali-activated materials. Use only a single terminology

 

- Cost is a crucial issue in the construction industry and although nano particles have a high cost the authors do not mention it even once

 

- -Comments on the toxicity of various nanomaterials for human health is also needed and the authors must comment on the safety procedures that they used in this study. See for instance

Silva, F., Arezes, P., & Swuste, P. (2019). Risk management: Controlling occupational exposure to nanoparticles in construction. In Nanotechnology in Eco-efficient Construction(pp. 755-784). Woodhead Publishing.

 

Buzea, C., & Pacheco, I. (2019). Toxicity of nanoparticles. In Nanotechnology in Eco-efficient Construction (pp. 705-754). Woodhead Publishing.

Author Response

Response to Reviewer 3 Comments

• -We live now in a climate emergency so its most strange that the authors have not start the paper by mentioning exactly that. It seems that they are not aware about the words of a Professor of Physics at the University of Oxford authored a paper where one can read the following:

 “Let’s get this on the table right away, without mincing words. With regard to the climate crisis, yes, it’s time to panic”

Pierrehumbert, R., 2019. There is no Plan B for dealing with the climate crisis. Bulletin of the Atomic Scientists, pp.1-7.

So please start the introduction by draw a connection between environmental degradation and resource efficiency.

Response 1: Thank you indeed for your valuable comments, the manuscript was revised with more details.

 

• Remove sustainable from the title and from abstract because no LCA was carried out. Even because sodium silicate and sodium hydroxide have a high carbon footprint. Let´s also no forget that Ouellet-Plamondon and Habert (2014) showed that only ´one part alkali-activated` binders shows carbon footprint levels much lower than Portland cement based mixtures.

Ouellet-Plamondon, C. ; Habert, G. (2014) Life cycle analysis (LCA) of alkali-activated cements and concretes. In Handbook of Alkali-Activated Cements, Mortars and Concretes, 663-686 (Eds) WoodHead Publishing-Elsevier, Cambridge.

Response 2: Agree, The term (sustainable) was removed.

 

• The authors should read the paper below to have an update about these materials:

Palomo A, Maltseva O, Garcia-Lodeiro I and Fernández-Jiménez A (2021) Portland Versus Alkaline Cement: Continuity or Clean Break: “A Key Decision for Global Sustainability”. Front. Chem. 9:705475. doi: 10.3389/fchem.2021.705475.

Response 3: Thank you indeed. The paper was clearly checked and understood.

 

• The first phrase of the abstract must be a summary of the introduction.

Response 4: Agree, the abstract section was rephrased with more details.

 

• “significant reductions in both natural resource use and CO2 emissions”

Comment: Where´s the evidence of that ?.

Response 5: Agree, the introduction section was rephrased with more details.

 

• ”Geopolymer 58 concrete (GPC) is made without the use of heat and emits no CO2 Comment: Remove that phrase because is scientific inacurate.

.

Response 6: Agree, the sentences were deleted.

 

• Avoid mixing geopolymers with alkali-activated materials. Use only a single terminology.

Response 7: Agree, the manuscript was rechecked and revised.

 

• Cost is a crucial issue in the construction industry and although nano particles have a high cost the authors do not mention it even once.

Response 8: Agree, the introduction section was revised with more details.

 

• Comments on the toxicity of various nanomaterials for human health is also needed and the authors must comment on the safety procedures that they used in this study. See for instance

Silva, F., Arezes, P., & Swuste, P. (2019). Risk management: Controlling occupational exposure to nanoparticles in construction. In Nanotechnology in Eco-efficient Construction(pp. 755-784). Woodhead Publishing.

Buzea, C., & Pacheco, I. (2019). Toxicity of nanoparticles. In Nanotechnology in Eco-efficient Construction (pp. 705-754). Woodhead Publishing.

Response 9: Agree, kindly, the toxicity section was added to the revised manuscript.

 

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

Dear authors, thank you for the revised version. It has been well-revised based on the reviewer's comments and can be accepted for publication.

Reviewer 2 Report

well revised

Reviewer 3 Report

The revised paper can be accepted