Research on the Performance of Recycled-Straw Insulating Concrete and Optimization Design of Matching Ratio
Round 1
Reviewer 1 Report (Previous Reviewer 1)
The authors improved the second submission of the paper and its quality and addressed properly my comments. However, I urge the authors to proofreading their papers one more time.
Author Response
Response to Reviewer 1 Comments
We appreciate your time and effort in reviewing our manuscript and greatly value your constructive comments and suggestions for improvement. We respond to each of your remarks below. Thank you!
Point 1: The authors improved the second submission of the paper and its quality and addressed properly my comments. However, I urge the authors to proofreading their papers one more time.
Response 1: We are deeply thankful for the critique and suggested experiments that have greatly improved our manuscript. According to your comments, we have checked and proofreading the manuscript again.
Thank you for your insightful and thorough review of our manuscript. Your constructive remarks helped us strengthen those areas of the manuscript that you have pointed out. We are more than happy to further revise the manuscript if you feel that we have failed to implement the suggested changes satisfactorily. However, we hope the revised version of the manuscript meets your expectations.
Author Response File: 
Author Response.pdf
Reviewer 2 Report (Previous Reviewer 2)
This manuscript presents a new way to preparing insulating materials from recycled straw and recycled concrete. I suggest the authors revise the manuscript according the comments below.
The abstract needs improving. It needs to be understood when presented separately from the manuscript. For example, In Lines 20 to 22, it makes no sense by giving a maximum temperature because the readers will not know what the temperature meant and how it was measured.
The writing English still needs improving. I suggest the authors refer to a language editor.
Figs 3, 4, and 5 can be removed as they contribute little to the topic discussed.
Section 2.4. The heat transfer model seems too simple. Convection, which is very important for heat transfer in porous materials, was not modeled. Thus, the method needs justifying.
Section 3.2.1. The discussion here needs more interaction with existing publications. For example, when discussing the effect of pozzolanic reaction, the authors can refer to C. Li et al., Cement and Concrete Research 92 (2017) 98–109.
Line 300, “cement slurry” needs to be replaced by “cement paste”.
Figs 12 to 14 needs modifying. I do not think it a good idea to show the brand of the software in the figures. Moreover, the size of the figures needs to be adjusted so that the words on the figures can be read clearly.
The writing English needs improving. I suggest the authors refer to a language editor.
Author Response
Response to Reviewer 2 Comments
We appreciate your time and effort in reviewing our manuscript and greatly value your constructive comments and suggestions for improvement. We respond to each of your remarks below. Thank you!
Point 1: The abstract needs improving. It needs to be understood when presented separately from the manuscript. For example, In Lines 20 to 22, it makes no sense by giving a maximum temperature because the readers will not know what the temperature meant and how it was measured.
Response 1: Thank you for your valuable suggestions for improvement. We are very sorry for our negligence of the explanation. The parts of the abstract have been modified accordingly according to your suggestions. Hope our improvements to the manuscript can meet your expectations.
Point 2: The writing English still needs improving. I suggest the authors refer to a language editor.
Response 2: Thank you very much for your valuable suggestions. According to your comments, we have consulted relevant English editors to make English modifications.
Point 3: Figs 3, 4, and 5 can be removed as they contribute little to the topic discussed.
Response 3: Thank you very much for your valuable suggestions. Figure 3 shows the appearance of the straw fibers used in this research, which can intuitively allow readers to obtain the morphology of the straw fibers. Figure 4 is a picture of the equipment used to test the thermal conductivity, Figure 5 is the test block used to test the thermal conductivity. These two figures and the steps of the thermal conductivity test can give readers a better understanding of the test steps of the thermal conductivity test. Hope our interpretation of these figures can meet your expectations.
Point 4: Section 2.4. The heat transfer model seems too simple. Convection, which is very important for heat transfer in porous materials, was not modeled. Thus, the method needs justifying.
Response 4: Thank you very much for your valuable suggestions, The heat transfer in porous materials is exactly what we need to work on in the future, and we are working on it, and you will see research in this area in our future work.
Point 5: Section 3.2.1. The discussion here needs more interaction with existing publications. For example, when discussing the effect of pozzolanic reaction, the authors can refer to C. Li et al., Cement and Concrete Research 92 (2017) 98–109.
Response 5: Thank you for your valuable suggestions for improvement. We have added relevant literature references to the discussion. And the literature you proposed has been referred to and the serial number is [59].
Point 6: Line 300, “cement slurry” needs to be replaced by “cement paste”.
Response 6: Thank you very much for your valuable suggestions. We've replaced the word "cement slurry" in the manuscript with "cement paste."
Point 7: Figs 12 to 14 needs modifying. I do not think it a good idea to show the brand of the software in the figures. Moreover, the size of the figures needs to be adjusted so that the words on the figures can be read clearly.
Response 7: Thank you very much for your valuable suggestions. Figure 12-14 has been modified according to your suggestion.
Thank you for your insightful and thorough review of our manuscript. Your constructive remarks helped us strengthen those areas of the manuscript that you have pointed out. We are more than happy to further revise the manuscript if you feel that we have failed to implement the suggested changes satisfactorily. However, we hope the revised version of the manuscript meets your expectations.
Author Response File: Author Response.pdf
Reviewer 3 Report (New Reviewer)
General Comments:
- The title clearly describes the focus of the research, and it provides a good overview of the study's objectives.
- The abstract provides a concise summary of the research, including the key findings and implications.
- The authors' affiliations are clearly stated, allowing for easy identification of their institutional affiliations.
Specific Comments:
- It would be beneficial if the introduction provided more background information on the significance of using recycled-straw insulating concrete and its potential advantages over traditional materials.
- The methodology section should provide more details on the experimental setup, including the specific testing procedures and equipment used for evaluating the mechanical and thermal properties of the recycled-straw insulating concrete.
- The results presented in the abstract could be expanded upon in the main body of the article, providing more detailed numerical data and analysis to support the conclusions.
- The discussion section should further explore the practical implications of the research findings and address any limitations or potential areas for future research.
- It would be helpful to include a conclusion section that summarizes the key findings and their implications for the use of recycled-straw insulating concrete in building envelopes.
- The keywords effectively capture the main topics and techniques used in the research.
Language and Style:
- The overall language and writing style are clear and concise, making the article easy to understand.
- Some sentences could be rephrased or improved for clarity. For example, in sentence 20, it is unclear what is meant by "1.45 times higher than the maximum temperature of plain concrete." Clarifying the comparison would be helpful.
- The abbreviations used in the abstract should be defined upon their first mention to ensure clarity for readers who are not familiar with them.
Overall, the research provides valuable insights into the mechanical and thermal properties of recycled-straw insulating concrete. Addressing the specific comments mentioned above would strengthen the manuscript and enhance its contribution to the field.
Author Response
Response to Reviewer 3 Comments
We appreciate your time and effort in reviewing our manuscript and greatly value your constructive comments and suggestions for improvement. We respond to each of your remarks below. Thank you!
General Comments:
Point 1: The title clearly describes the focus of the research, and it provides a good overview of the study's objectives.
Response 1: Your positive feedback and encouragement have been instrumental in enhancing the quality of the final manuscript, and I am truly honored to have had the benefit of your expertise and insights.
Point 2: The abstract provides a concise summary of the research, including the key findings and implications.
Response 2: Thank you for your recognition of this paper and we will continue to improve this manuscript to meet your expectations.
Point 3: The authors' affiliations are clearly stated, allowing for easy identification of their institutional affiliations.
Response 3: Sincerely thank you for your recognition of our paper, we will further improve the paper to meet your expectations.
Specific Comments:
Point 1: It would be beneficial if the introduction provided more background information on the significance of using recycled-straw insulating concrete and its potential advantages over traditional materials.
Response 1: Thank you very much for your valuable suggestions. We have adapted accordingly to your recommendations. Compared with ordinary concrete, recycled-straw insulating concrete is the recycling of construction solid waste and agricultural waste resources, which can reduce the waste of resources and realize the recycling of resources, in line with the characteristics of sustainable development. Recycled-straw insulating concrete applied to the enclosure structure can save heating costs in winter and reduce carbon dioxide emissions, which has significant economic and environmental significance for some areas with low outdoor temperature in winter and long heating period. we have added the suggested content to the manuscript on page 3 line 117~120.
Point 2: The methodology section should provide more details on the experimental setup, including the specific testing procedures and equipment used for evaluating the mechanical and thermal properties of the recycled-straw insulating concrete.
Response 2: Thank you for bringing these points up for discussion. We have added the figure of the equipment for compressive strength test and testing procedures for compressive strength in the methodology section. The contents added are as follows: The equipment for testing compressive strength is shown in Figure 1. The steps for testing compressive strength are as follows:1. The specimens were taken out from the curing room, then wiped the attached water off the surface of the specimen with a wet washcloth wrung out. 2. The specimens were placed in the center of the lower pressure plate surface of the testing machine, then started the testing machine. 3. Uniform and continuous loading in the test process, the loading speed was set at 0.4~0.6MPa per second. Compressive strength was recorded until the specimen was damaged. At the same time, you can see these suggested content to the manuscript on page 7 line 206~224.
Figure 1. servo universal testing machine model HCT306A
Point 3: The results presented in the abstract could be expanded upon in the main body of the article, providing more detailed numerical data and analysis to support the conclusions.
Response 3: Thank you very much for your valuable suggestions. The results presented in the abstract were expanded in 3.4 Optimal Design of Mix Ratio and 3.5 Finite Element Simulation Analysis of Wall Temperature Field of this manuscript. According to the data of compressive strength and thermal conductivity shown in Table 12, these two types of data are put into formula (3)~(5) for calculation, and the total efficiency coefficient of each group is calculated. The summary of the calculated values of the total efficiency coefficient is shown in Table 12. It can be seen that the total efficiency coefficient of group 12 is the highest, which has a recycled coarse aggregate replacement ratio of 70%, fly ash replacement ratio of 20%, and straw content of 1%. This optimal mix ratio results in compressive strength of 30.93 MPa and thermal conductivity of 0.5051 W/ (m. K). The interior surface temperature value obtained by steady-state thermal analysis of the recycled-straw insulating concrete wall is shown in Table 13. From Table 13 we can know that the interior wall temperature of the recycled-straw insulating concrete wall with the optimal ratio is 19.01℃, while that of the plain concrete wall is 7.77℃. The interior surface temperature of recycled-straw insulating concrete wall is 1.45 times that of plain concrete interior wall, which confirms the thermal insulation performance of recycled-straw insulating concrete.
Point 4: The discussion section should further explore the practical implications of the research findings and address any limitations or potential areas for future research.
Response 4: Thank you very much for your valuable suggestions. In the conclusion part, the practical implications of the research findings and address any limitations or potential areas for future research are supplemented. you can see these suggested content to the manuscript on page 24 line 552~569
Point 5: It would be helpful to include a conclusion section that summarizes the key findings and their implications for the use of recycled-straw insulating concrete in building envelopes.
Response 5: Thank you for providing these insights. We have adapted accordingly to your recommendations. You can see these suggested content to the manuscript on page 24 line 529~541.
Point 6: The keywords effectively capture the main topics and techniques used in the research.
Response 6: Your revisions are the key to improving our manuscript. Thank you for your high evaluation of our manuscript.
Language and Style:
Point 1: The overall language and writing style are clear and concise, making the article easy to understand.
Response 1: Thank you very much for your high evaluation of our manuscript. Hope our improvements to the manuscript can meet your expectations.
Point 2: Some sentences could be rephrased or improved for clarity. For example, in sentence 20, it is unclear what is meant by "1.45 times higher than the maximum temperature of plain concrete." Clarifying the comparison would be helpful.
Response 2: Thank you for your valuable suggestions for improvement. We are very sorry for our negligence of the explanation. What we want to express here is that the steady-state thermal analysis of recycled-straw insulating concrete wall and plain concrete wall was carried out by finite element software. The simulation results showed that the insulation performance of the recycled-straw insulating concrete walls was improved by 145% compared with plain concrete wall. Compared with plain concrete, recycled-straw insulating concrete has a better thermal insulation effect. You can see these suggested content to the manuscript on page 1 line 24~27.
Point 3: The abbreviations used in the abstract should be defined upon their first mention to ensure clarity for readers who are not familiar with them.
Response 3: Thank you for your valuable suggestions for improvement."ANSYS" is the abbreviation of "ANSYS,Inc". ANSYS software is a large scale universal finite element analysis software developed by American ANSYS Company. ANSYS Workbench is a version of finite element software released by ANYSYS.
Thank you for your insightful and thorough review of our manuscript. Your constructive remarks helped us strengthen those areas of the manuscript that you have pointed out. We are more than happy to further revise the manuscript if you feel that we have failed to implement the suggested changes satisfactorily. However, we hope the revised version of the manuscript meets your expectations.
Author Response File: Author Response.pdf
Reviewer 4 Report (New Reviewer)
Dear Authors ,
The present paper is interesting and contains valuable information, and the structure of the paper is well-designed. However, there are some major comments on the writing quality and the analysis of the results.
（1）The conclusion is not written in detail enough, and the language needs to be reorganized.
（2）Some physical and mechanical properties of straw need to be stated, and the insulation performance should be closely related to the moisture content and other properties of the straw.
（3）The heat transfer coefficient of concrete with different properties will greatly affect the accuracy of finite element calculation. Please clarify how to select the heat transfer coefficient of various types of concrete.
Minor editing of English language required
Author Response
Response to Reviewer 4 Comments
We appreciate your time and effort in reviewing our manuscript and greatly value your constructive comments and suggestions for improvement. We respond to each of your remarks below. Thank you!
Point 1: The conclusion is not written in detail enough, and the language needs to be reorganized.
Response 1: Thank you very much for your valuable suggestions. We have made corresponding modifications to the conclusion according to your suggestions.
Point 2: Some physical and mechanical properties of straw need to be stated, and the insulation performance should be closely related to the moisture content and other properties of the straw.
Response 2: Thanks for your suggestion. According to your suggestion, we have added the table of physical performance parameters of straw fibers into the manuscript. You can see these suggested content to the manuscript on page 5 line 163~165.The physical performance parameters of straw fibers are shown in Table 3.
Point 3: The heat transfer coefficient of concrete with different properties will greatly affect the accuracy of finite element calculation. Please clarify how to select the heat transfer coefficient of various types of concrete.
Response 3: Thank you very much for your valuable suggestions. The heat transfer coefficient is represented by K, which refers to the heat transferred by unit area in unit time when the air on both sides of the enclosure structure is unit temperature difference under the steady-state condition. Heat transfer coefficient is calculated according to formula (1)~(3). According to formula (1)~(3), heat transfer coefficient and thermal resistance are reciprocal to each other, and the thermal resistance of materials is related to the thickness and thermal conductivity of materials. In this research, finite element software is used for steady-state thermal analysis of the wall. The temperature field of the system in steady-state heat transfer does not change with time, so in steady-state heat transfer analysis, the heat transfer coefficient can be calculated for steady-state thermal analysis only by knowing the thermal conductivity and thickness of the material. In the finite element software, the thickness of the simulated wall is 0.24m. After setting the thermal conductivity measured by the thermal conductivity measuring instrument, the steady-state thermal analysis of the wall can be simulated.
Thank you for your insightful and thorough review of our manuscript. Your constructive remarks helped us strengthen those areas of the manuscript that you have pointed out. We are more than happy to further revise the manuscript if you feel that we have failed to implement the suggested changes satisfactorily. However, we hope the revised version of the manuscript meets your expectations.
Author Response File: Author Response.pdf
Reviewer 5 Report (New Reviewer)
This paper investigated the effects of recycled coarse aggregate replacement ratio, fly ash replacement ratio, and straw content on the mechanical and thermal properties of recycled-straw insulating concrete. The results showed that the compressive strength of the recycled straw insulating concrete with the optimal ratio was found to be 30.93 MPa and thermal conductivity was 0.5051W/ (m. K).
The article is well research and contains novel idea that adds some information to the body of knowledge. Likewise, the paper complies with the writing standard of the Journal and all tests were done according to the normal standard of tests. Based on these aforementioned, I recommend that the research paper can be accepted for publication after minor revision.
1. What is the cement loss on ignition in Table 1? Need to supplement.
2. The particle size distribution has a significant impact on the performance of concrete. Please supplement the raw material particle size distribution curve.
3. As an important additive for preparing insulating concrete, the author needs to elaborate on the parameters such as fiber diameter, length, and density of rice husk fiber.
4. The 3 in 2380Kg/m3 of line 126, please superscript.
5. Please use a three line table format for Table 4, and adjust the format of Table 5.
6. From Table 2, it can be seen that the water cement ratio during the author's preparation of adiabatic concrete is constantly changing. Please explain the effect of water adhesive ratio on insulation performance.
7. The author explored in lines 268 to 309 that the strength of concrete decreases with the increase of recycled aggregate, fly ash, and rice husk fiber content. In fact, from the author's experimental proportions in Table 5, it can be seen that the water cement ratio of concrete increases with the increase of rice husk fiber content, which has a crucial impact on the strength of concrete.
8. Please remove the spaces in 7 and d, as well as in 28 and d, on lines 320 and 321, respectively.
9. This article only briefly describes the experimental phenomenon and does not reflect from the mechanism that the author uses rice husk fibers to promote the preparation of adiabatic concrete in concrete. However, the reason why it promotes insulation has not been elucidated from a mechanistic perspective.
10. The author used finite element method for simulation. The author needs to elaborate in detail on how to perform grid partitioning during the simulation process and how to set parameters such as the model.
This paper investigated the effects of recycled coarse aggregate replacement ratio, fly ash replacement ratio, and straw content on the mechanical and thermal properties of recycled-straw insulating concrete. The results showed that the compressive strength of the recycled straw insulating concrete with the optimal ratio was found to be 30.93 MPa and thermal conductivity was 0.5051W/ (m. K).
The article is well research and contains novel idea that adds some information to the body of knowledge. Likewise, the paper complies with the writing standard of the Journal and all tests were done according to the normal standard of tests. Based on these aforementioned, I recommend that the research paper can be accepted for publication after minor revision.
1. What is the cement loss on ignition in Table 1? Need to supplement.
2. The particle size distribution has a significant impact on the performance of concrete. Please supplement the raw material particle size distribution curve.
3. As an important additive for preparing insulating concrete, the author needs to elaborate on the parameters such as fiber diameter, length, and density of rice husk fiber.
4. The 3 in 2380Kg/m3 of line 126, please superscript.
5. Please use a three line table format for Table 4, and adjust the format of Table 5.
6. From Table 2, it can be seen that the water cement ratio during the author's preparation of adiabatic concrete is constantly changing. Please explain the effect of water adhesive ratio on insulation performance.
7. The author explored in lines 268 to 309 that the strength of concrete decreases with the increase of recycled aggregate, fly ash, and rice husk fiber content. In fact, from the author's experimental proportions in Table 5, it can be seen that the water cement ratio of concrete increases with the increase of rice husk fiber content, which has a crucial impact on the strength of concrete.
8. Please remove the spaces in 7 and d, as well as in 28 and d, on lines 320 and 321, respectively.
9. This article only briefly describes the experimental phenomenon and does not reflect from the mechanism that the author uses rice husk fibers to promote the preparation of adiabatic concrete in concrete. However, the reason why it promotes insulation has not been elucidated from a mechanistic perspective.
10. The author used finite element method for simulation. The author needs to elaborate in detail on how to perform grid partitioning during the simulation process and how to set parameters such as the model.
Author Response
Response to Reviewer 5 Comments
We appreciate your time and effort in reviewing our manuscript and greatly value your constructive comments and suggestions for improvement. We respond to each of your remarks below. Thank you!
Point 1: What is the cement loss on ignition in Table 1? Need to supplement.
Response 1: Thank you very much for your valuable suggestions. According to the standard GB175-2007 "General Purpose Portland Cement", the loss of ordinary Portland cement should be less than 5, and the loss of ordinary Portland cement of P.O 42.5 used in this research is 2.1, which meet the requirements of relevant standards.
Point 2: The particle size distribution has a significant impact on the performance of concrete. Please supplement the raw material particle size distribution curve.
Response 2: Thank you very much for your valuable suggestions. The particle size of recycled and natural aggregates used in this research is 5-16mm. The particle size of the sand is 0-5mm, and its fineness modulus is 3.05, which belongs to medium sand.We have added screening curves for natural aggregate and recycled aggregate, as well as for sand. You can see the proposed additions on page 4 of the manuscript on line 149 and page 5 on line 159-160.
Point 3: As an important additive for preparing insulating concrete, the author needs to elaborate on the parameters such as fiber diameter, length, and density of rice husk fiber.
Response 3: Thanks for your suggestion. The appearance of the straw fibers can be observed in Figure 4. Straw fibers were physically processed by shearing them into small segments of 5-10 mm size. According to your suggestion, we have added the table of physical performance parameters of straw fibers into the manuscript. You can see these suggested content to the manuscript on page 5 line 162.The physical performance parameters of straw fibers are shown in Table 3.
Point 4: The 3 in 2380Kg/m3 of line 126, please superscript.
Response 4: Thank you very much for your valuable suggestions. We are sorry to this detail error, We have adapted accordingly to your recommendations.
Point 5: Please use a three line table format for Table 4, and adjust the format of Table 5.
Response 5: Thank you for your valuable suggestions for improvement. We apologize for neglecting to check the chart format. We have changed Table 4 to a three line table format and reformatted Table 5.
Point 6: From Table 2, it can be seen that the water cement ratio during the author's preparation of adiabatic concrete is constantly changing. Please explain the effect of water adhesive ratio on insulation performance.
Response 6: Thank you very much for your valuable suggestions. In this experiment, the water absorption of recycled aggregate was 3.4%, while that of natural aggregate was 1.11%. As the water absorption of recycled coarse aggregate is about 3 times that of natural aggregate, additional water is used to reduce the effect of high water absorption of recycled coarse aggregate on the effective water-cement ratio. The formula for calculating additional water consumption is the water absorption of recycled aggregate minus the water absorption of natural aggregate, and then multiplied by the quality of recycled aggregate. It can be seen from the physical property parameters of straw in Table 3 that the mass water absorption of straw is (353±16) %. In order to prevent the influence of high water absorption of straw on the effective water-cement ratio, good workability needs to be maintained. Combined with relevant literature to consider, for each 1% increase in straw content, approximately 10-13kg of additional water is added per cubic meter of concrete.
Point 7: The author explored in lines 268 to 309 that the strength of concrete decreases with the increase of recycled aggregate, fly ash, and rice husk fiber content. In fact, from the author's experimental proportions in Table 5, it can be seen that the water cement ratio of concrete increases with the increase of rice husk fiber content, which has a crucial impact on the strength of concrete.
Response 7: Thank you very much for your valuable suggestions. The increase in the water-cement ratio you refer to here is due to the additional water for recycled aggregate and straw fibers. If no additional water is added, the water absorption of recycled aggregate and straw is too large, which will lead to the actual water consumption of concrete is reduced, resulting in the actual water-cement ratio is reduced.
Point 8: Please remove the spaces in 7 and d, as well as in 28 and d, on lines 320 and 321, respectively.
Response 8: Thank you for your valuable suggestions for improvement. The problem you pointed out has been corrected.
Point 9: This article only briefly describes the experimental phenomenon and does not reflect from the mechanism that the author uses rice husk fibers to promote the preparation of adiabatic concrete in concrete. However, the reason why it promotes insulation has not been elucidated from a mechanistic perspective.
Response 9: Thank you for your valuable suggestions for improvement. In the discussion part, there are references to other scholars' literature to do the analysis of the related concrete mechanism leading to insulation. The straw fiber contains honeycomb pores and is mainly comprised of substances like lignin and cellulose, which are poor conductors of heat, resulting in better insulation performance. Additionally, straw increases the internal porosity of concrete, leading to more closed voids and lower thermal conductivity, which improved its thermal performance. Straw fibers mainly contains cellulose and hemicellulose. The sugars precipitated from organic cellulose will prevent the hydration reaction of cement, that is, hinder the growth of Ca (OH)2 crystals, resulting in a “retarded coagulation” phe-nomenon. In addition, the compatibility between fiber and cement slurry is poor, which will affect the internal molecular crystallization and reduce the amount of C-S-H (calcium-silicate-hydrate) gel production generated. Hemicellulose is also known to delay the hydration of C2S (dicalcium silicate), and hinder the generation of Aft (ettringite). These mechanical reactions will cause the strength of concrete to decrease, so the internal porosity of concrete will increase, and its thermal conductivity will decrease.The reason why it promotes insulation from a mechanistic perspective is exactly what we need to work on in the future, and we are working on it, and you will see research in this area in our future work.
Point 10: The author used finite element method for simulation. The author needs to elaborate in detail on how to perform grid partitioning during the simulation process and how to set parameters such as the model.
Response 10: Thanks for your suggestion. According to your suggestion, The detailed process of finite element simulation is described in the manuscript. You can see these suggested content to the manuscript on page 10 line 271-304. Hope our improvements to the manuscript can meet your expectations.
Thank you for your insightful and thorough review of our manuscript. Your constructive remarks helped us strengthen those areas of the manuscript that you have pointed out. We are more than happy to further revise the manuscript if you feel that we have failed to implement the suggested changes satisfactorily. However, we hope the revised version of the manuscript meets your expectations.
Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report (Previous Reviewer 2)
The manuscript has been much improved. It can be accepted for publication.
Reviewer 4 Report (New Reviewer)
It is recommended to accept the manuscript in the existing format.
This manuscript is a resubmission of an earlier submission. The following is a list of the peer review reports and author responses from that submission.
Round 1
Reviewer 1 Report
Comments for author File: Comments.pdf
Author Response
Point 1: In scientific technical paper, the use of “we” at the beginning of the sentence should be avoided such as “we used” “we evaluated” “we placed” “we added”. Please correct it accordingly throughout the paper. There are countless of those mistakes.
Response 1: Thanks for your suggestion. All the English writing mistakes you mentioned above have been corrected.
Point 2: Line 132: did the authors conduct any treatment on the straw fibers? And why?
Response 2: We are sincerely thankful to you for reviewing our manuscript and giving the significant suggestions. The straw fibers were physically processed by shearing them into small segments of 5-10mm, placing in a dry place to prevent the straw from getting wet.
Point 3: The authors mentioned in line 180 that there are “six specimens each” but I don’t see any error bars in figure 7, 8, 9 and 10.
Response 3: Thanks for your suggestion. According to the GB/T 50081-2002, “Standard for Mechanical Properties of Ordinary Concrete”, the mechanical properties test of ordinary concrete should take three specimens as a group, and the arithmetic mean value of the measured values of the three specimens is taken as the strength value of the group of specimens. Each set of six test blocks, half of which were used to test the 7d compressive strength of concrete, and the remaining three were used to test the 28d compressive strength of concrete.
Point 4: how the authors determine the levels of each factors? Any references? The values in the table appear arbitrary.
Response 4: Thanks for your suggestion. The level of each factor is determined according to the reference literature, and the corresponding literature reference has been added.
Point 5: In general, the tables and figures in the manuscript should be placed after being mentioned in the text, and not the opposite. This should be corrected.
Response 5: Thank you for remarking this point. All the tables and figures in the manuscript have been put after the text mentioned.
Point 6: Figures 12, 13 and 14 appear exactly the same (same color of the wall, although different legend). How can we differentiate between the different temperatures?
Response 6: Thank you very much for your valuable suggestions. The wall colors in figure 12, 13, and 14 are different. The inner wall is red while the outer wall is blue. The partial enlargement of the finite element analysis of the wall is shown in Figure 1, and the change of the wall temperature value is shown in Figure 2.
Figure 1 The partial enlargement of the finite element analysis of the wall
Figure 2 The change of the wall temperature value
Point 7: Conclusions: a few sentences need to added to emphasize the importance of the work.
Response 7: Thanks for your suggestion.The conclusion section adds a statement about the importance of the research work. The use of solid waste resources effectively alleviates the resource waste problem and has significant environmental and socio-economic benefits. Recycled-straw insulating concrete has favorable thermal insulation properties, and can save energy and costs when used in actual projects, promoting the development of green building practices.
Point 8: The optimal ratio of straw-regenerated insulation concrete must be explicitly specified in the conclusion section.
Response 8: Thank you very much for your valuable suggestions. The optimal mix ratio has been added at the conclusion. The optimal mix ratio for recycled-straw insulating concrete falls into Group 12, which has a recycled coarse aggregate replacement ratio of 70%, fly ash replacement ration of 20%, and straw content of 1%. This mix ratio results in a compressive strength of 30.93 MPa and thermal conductivity of 0.5051 W/ (m. K).
Point 9: A recommendation section is needed.
Response 9: Thanks for your suggestion.The recommendations have been added in the conclusion section.
Thank you for your inciteful and thorough review of our manuscript. Your constructive remarks helped us strengthen those areas of the manuscript that you have pointed out. We are more than happy to further revise the manuscript if you feel that we have failed to implement the suggested changes satisfactorily. However, we hope the revised version of the manuscript meets your expectations.
Author Response File: Author Response.pdf
Reviewer 2 Report
This manuscript used recycled straw for thermal insulation cementitious materials production. The English writing needs extensive improvements. The technical part also needs improving. I do not suggest the manuscript be published in its current form.
1) I can see many terms that are mistakenly used. For example, straw-recycled in the title should be replaced by recycled-straw. All terms used in orthogonal array analysis should be checked, e.g., extreme difference. Lines 286, volcanic ash effect should be replaced by pozzolanic reaction. Lines 298, what is slow setting. Lines 359, regenerated aggregate.
2) The analyses on tests results are not satisfactory. Many claims are not supported by test results or literature. For example, Lines 279 to 306. Doesn’t fly ash react before 7d? Does aluminates in FA react with Ca(OH)2? Is there any literature supporting the presence of cellulose and hemicellulose in straw and the impacts of these two substances on cement hydration?
Overall, I think the manuscript is still premature for consideration for publication.
The English writing needs much improving in order not to mislead the readers.
Author Response
We appreciate your time and effort in reviewing our manuscript and greatly value your constructive comments and suggestions for improvement. We respond to each of your remarks below. Thank you!
Point 1: I can see many terms that are mistakenly used. For example, straw-recycled in the title should be replaced by recycled-straw. All terms used in orthogonal array analysis should be checked, e.g., extreme difference. Lines 286, volcanic ash effect should be replaced by pozzolanic reaction. Lines 298, what is slow setting. Lines 359, regenerated aggregate.
Response 1: Thank you for bringing these points up for discussion. We are sorry to this detail mistake. The straw-recycled in the title has been replaced by recycled-straw. All terms used in orthogonal array analysis have been checked,e.g, extreme difference has been replaced by range analysis. Volcanic ash effect has been replaced by pozzolanic reaction.The slow setting in line 298 has been replaced by retarded coagulation. The regenerated aggregate in line 359 has been replaced by recycled aggregate.
Point 2: The analyses on tests results are not satisfactory. Many claims are not supported by test results or literature. For example, Lines 279 to 306. Doesn’t fly ash react before 7d? Does aluminates in FA react with Ca(OH)2? Is there any literature supporting the presence of cellulose and hemicellulose in straw and the impacts of these two substances on cement hydration?
Response 9: Thank you very much for your valuable suggestions. The early 7d reaction of fly ash mentioned here is slower rather than no reaction at all. Fly ash is a kind of volcanic ash material, which has no gelling property. In the presence of water at room temperature, after the hydration reaction of cement, fly ash can carry out a secondary reaction with Ca(OH) 2, the product of hydration reaction in concrete, namely volcanic ash reaction, to generate calcium silicate hydrate gel that is insoluble in water. Aluminate reacts with calcium hydroxide to precipitate ettringite. Relevant references have been added to confirm the presence of cellulose and hemicellulose in straw and the impacts of these two substances on cement hydration.
Thank you for your inciteful and thorough review of our manuscript. Your constructive remarks helped us strengthen those areas of the manuscript that you have pointed out. We are more than happy to further revise the manuscript if you feel that we have failed to implement the suggested changes satisfactorily. However, we hope the revised version of the manuscript meets your expectations.
Author Response File: Author Response.pdf
Reviewer 3 Report
This paper presented the performance of straw-recycled insulating concrete and its optimization design ratio. The comments can be found as follows:
1. Line 22: more specific construction solid waste is required.
2. Line 59: what are the differences between these two sources?
3. Line 64: what is EPS?
4. Line 78-79: what does it mean by "to ultra-high performance concrete containing dune sand"?
5. Line 87: what does it mean "the reinforcement diameter"?
6. Line 88: how straw ash concrete showed better corrosion resistance than ordinary concrete?
7. Line 129: please try to avoid the term "we" in academic research article.
8. Line 130: Please provide more specifics about Class II fly ash. How many classes of fly ash are classified and by whom?
9. Line 252: please check the typing error ".the".
10. Line 252-255: it is hard to understand; please revise it.
11. Line 288-290: how to confirm this discussion? is there any backup information, test or reference to support?
12. Line 300-302: similar to comment no. 11, the solid evident or support is required.
13. Table 7: please clearly indicate the meaning of SS, df, MS, F, CV, and Sig.
14. Line 338-341: It hard to believe this discussion unless it has more support evident.
15. Line 346-347: please recheck this discussion as the thermal conductivity as remarkably dropped when 10% fly ash was added.
16. Is there any treatment for straw material prior to use it in this study? The straw is a bio-degradable material, which might negatively influence the properties of the concrete in long-term. Please make more discussion about this.
Editing English writing and checking grammar error is required.
Author Response
We appreciate your time and effort in reviewing our manuscript and greatly value your constructive comments and suggestions for improvement. We respond to each of your remarks below. Thank you!
Point 1: Line 22: more specific construction solid waste is required.
Response 1: Thanks for your suggestion. The construction solid waste in line 22 refers to construction solid waste from the reconstruction, demolition and new construction of engineering. The source of construction solid waste in this study is from pavement improvement projects.
Point 2: Line 59: what are the differences between these two sources?
Response 2: Thanks for your suggestion. The different sources here refer to the different types of recycled aggregates from the construction solid wastes taken from two different sites.
Point 3: Line 64: what is EPS?
Response 3: Thanks for your suggestion. EPS refers to expanded polystyrene, It is a lightweight polymer. It is the use of polystyrene resin to add foaming agent, at the same time heating softening, gas generation, the formation of a hard closed cell structure of the foam plastic.
Point 4: Line 78-79: what does it mean by "to ultra-high performance concrete containing dune sand"?
Response 4: Thank you very much for your valuable suggestions. This refers to the sand added to the ultra high performance concrete in this study is dune sand. The dune sand comes from the Tunisian Sahara Desert in the south of country, The particle size of the sand is fine.
Point 5: Line 87: what does it mean "the reinforcement diameter"?
Response 5: Thanks for your suggestion. This paragraph has been revised.
Point 6: Line 88: how straw ash concrete showed better corrosion resistance than ordinary concrete?
Response 6: Thanks for your suggestion. After replacing the cement with the straw ash admixture, the compactness of concrete is im-proved. Besides, the rebar corrosion rate is lowered, and the corrosion resistance of rebars is improved effectively, thereby enhancing the durability of concrete structures.
Point 7: Line 129: please try to avoid the term "we" in academic research article.
Response 7: Thanks for your suggestion. The term "we" in this article has been completely revised.
Point 8: Line 130: Please provide more specifics about Class II fly ash. How many classes of fly ash are classified and by whom?
Response 8: Thanks for your suggestion. According to GB/T1596-2005 "Fly Ash for cement and concrete" specification, fly ash for mixing concrete and mortar technical requirements. Fly ash has three grades, according to fineness, water requirement ratio, burning vector classification. The chemical composition of fly ash in this research is supplemented in detail in the paper.
Point 9: Line 252: please check the typing error ".the".
Response 9: Thanks for your suggestion. The typing error has been corrected.
Point 10: Line 252-255: it is hard to understand; please revise it.
Response 10: Thanks for your suggestion. This part has been revised. For the range analysis, `Ki is the average value of the same level of different factor, and the range value R refers to the difference between the maximum and minimum value of `Ki. The larger the value of R, the greater the influence of the level change of the factor (recycled coarse aggregate replacement ratio, fly ash replacement ratio, and straw content) on the performance of recycled-straw insulating concrete, the more important the factor.
Point 11: Line 288-290: how to confirm this discussion? is there any backup information, test or reference to support?
Response 11: Thanks for your suggestion. The corresponding references have been added here to support this discussion.
Point 12: Line 300-302: similar to comment no. 11, the solid evident or support is required.
Response 12: Thanks for your suggestion. The corresponding references have been added here.
Point 13: Table 7: please clearly indicate the meaning of SS, df, MS, F, CV, and Sig.
Response 13: Thanks for your suggestion. SS: sum of squares of deviation from mean; df: degree of freedom; MS: mean square; F: statistic; CV: coefficient of variation; sig: significance. The supplementary explanation has been made in the paper.
Point 14: Line 338-341: It hard to believe this discussion unless it has more support evident.
Response 14: Thanks for your suggestion. The corresponding references have been added in line 338-341.
Point 15: Line 346-347: please recheck this discussion as the thermal conductivity as remarkably dropped when 10% fly ash was added.
Response 15: Thanks for your suggestion. Changes have been made here, The thermal conductivity appears to decrease by 19.34% as the fly ash replacement ratio increases from 0% to 10%, and by 7.4% when the replacement ratio increases from 10% to 20%.
Point 16: Is there any treatment for straw material prior to use it in this study? The straw is a bio-degradable material, which might negatively influence the properties of the concrete in long-term. Please make more discussion about this.
Response 16: Thank you very much for your valuable suggestions. Considering that if the straw is treated in the early stage, it will increase the economic cost, and if the straw is treated with chemical specimens, there may be residue, which will affect the subsequent test results. Although incorporating straw fibers into concrete causes a decline in its mechanical properties, for some building envelopes with low mechanical requirements, It can lend a certain insulation effect and reduce costs while satisfying certain mechanical properties.
Thank you for your inciteful and thorough review of our manuscript. Your constructive remarks helped us strengthen those areas of the manuscript that you have pointed out. We are more than happy to further revise the manuscript if you feel that we have failed to implement the suggested changes satisfactorily. However, we hope the revised version of the manuscript meets your expectations.
Author Response File: Author Response.pdf
