Investigation Properties of Pervious and Water-Retaining Recycled Concrete to Mitigate Urban Heat Island Phenomena
JIE HU
Round 1
Reviewer 1 Report
1. The research objectives and the significance of the newly developed pervious concrete in the heat island effect mitigation should be clarified in the manuscript.
2. There is a lack of citations for the reviews and the literature content should be improved.
3. The author should clarify the side benefit of the material in resolve the heat island effect instead of hydric and hygroscopic properties of the pervious pavement only.
4. The author’s team should consider the color of the fabricated material which may significantly impact the urban heat islands effects.
5. Some figures are not sufficient to express the mechanism, the figure should be revised by adding more arrows...
6. In this research, Sorption\desorption test were one of the most important in this research to support the term “hygric properties of cool water-retaining” in the title. However, the research content may be insufficient to support the research objectives. Therefore, it is suggested to revised slightly the title to meet the quality of the journal.
7. Besides, the Figures system should be revised to meet the quality of the Journal.
Author Response
Thank you for your thoughtful and constructive feedback on the manuscript. I appreciate your insights and suggestions on how to improve the quality and clarity of the research presented in the article. (All changes are marked in red in the revised version).
Please see the attachment file that provide a point-by-point response to the reviewer’s comments
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Please find my comments to improve the paper:
1. Please write the paper title in one complete sentence. "Pervious" can be relocated at the second row, instead of writing it as pervi-ous.
2. Please double check your objective or aim of the research. Currently, there were three objectives stated in the write-up. Page 1, line 44, page 2, line 46 and page 2, line 72.
3. Add signposting sentences before Figure 4, after the Section 3.1 title. This is to guide and inform the reader about the figure location. This comment applies to sections 3.2, 3.3, 3.5, and 3.6.
4. Why citation [11] and [47] is written in line 189.
5. The decimal point is limited to 2. d.p. as in Figure 4.
6. Please state the location of the pervious concrete to be applied.
7. Rather than stating that "These findings have been supported by studies in many literature sources [15], [19], [60], [65]", please discuss in brief other researchers' findings which can support the study.
Author Response
Thank you for your thoughtful and constructive feedback on the manuscript. I appreciate your insights and suggestions on how to improve the quality and clarity of the research presented in the article. (All changes are marked in red in the revised version).
Please see the attachment file that provide a point-by-point response to the reviewer’s comments
Author Response File: Author Response.pdf
Reviewer 3 Report
In this paper, the authors focused on the improvement of hygric and water retention properties of pervious concrete to mitigate urban heat island phenomena.
Specific comments:
1. Please provide evidence to support the authors’ point of view in the Results and discussions.
2. Despite conducting a significant number of experiments, the article lacks a deep analysis of the results and fundamental analyses.
3. The importance of this work as well as novelty are unclear.
Author Response
Thank you for your thoughtful and constructive feedback on the manuscript. I appreciate your insights and suggestions on how to improve the quality and clarity of the research presented in the article. (All changes are marked in red in the revised version).
Please see the attachment file that provide a point-by-point response to the reviewer’s comments
Author Response File: Author Response.pdf
Reviewer 4 Report
Comments for author File: Comments.pdf
Author Response
Thank you for your thoughtful and constructive feedback on the manuscript. I appreciate your insights and suggestions on how to improve the quality and clarity of the research presented in the article. (All changes are marked in red in the revised version).
Please see the attachment file that provide a point-by-point response to the reviewer’s comments
Author Response File: Author Response.pdf
Reviewer 5 Report
Authors conducted some interesting. Unfortunately, within here presented research, there is a lack of scientific or practical contribution to the research topic and it is not on appropriate scientific or technical level to be considered for publication in this high impact journal. Within the introduction section, detailed literature review is missing considering to the topic covered in the paper. Materials and methods section are not properly presented and Results and discussion has some serious flaws. I have serious concerns about the applicability, appropriateness and accuracy of the used materials and methods and presented analyzes and discussions.
What is the origin of recycled aggregates, what kind of natural aggregates were used (crushed stone, diabase, dolomite, gravel…).
Entire section 2.2. Mix composition and preparation should be rewritten since it is confusing and unnecessarily filed with references. On the other hand, details on specimen preparation are missing and explanation on using pressure during specimen casting must be explained. Due to specimen casting, explanation on particular use and application of here presented material must be given. Generally, specimen preparation, material application and conducted tests are not aligned. If material is supposed to be used for pavers, specimen dimensions of 15x15x15 cm are not suitable. Also, there are existing standard for testing paves and paving flags (for example EN 1338 and EN 1339) and using test methods for ordinary concrete are not suitable. For example, pavers are characterized by bending not compressive strength. Also, if water retention is analyzed, freeze/thaw resistance must be analyzed as well.
Figure 3 is not a schematic chart, it is a photograph?
Figure 5 should be presented with the same scaling factor, figures are not comparable in here presented state.
Figure 9, correlation determined based on 3-4 points is not statistically relevant. These analyses should be omitted or more data should be provided for statistically relevant analyses.
Author Response
Thank you for your thoughtful and constructive feedback on the manuscript. I appreciate your insights and suggestions on how to improve the quality and clarity of the research presented in the article. (All changes are marked in red in the revised version).
Please see the attachment file that provide a point-by-point response to the reviewer’s comments
Author Response File: Author Response.pdf
Reviewer 6 Report
The work is experimental and concerns a very important problem of urban heat island (UHI) occurring in urban centers. Unlike other concepts of UHI mitigation (road surfaces, reflective surface and permeable concrete), the article presents the results of research on the improvement of hygroscopic properties and water retention.
The tests were carried out in dry and modular conditions using four different concretes on recycled aggregates (RA). It was shown that with the increase in the amount of RA, the water absorption increased by 75 liters compared to the reference samples. Thanks to the favorable results, suitability for paving and mitigating the UHI phenomenon was determined.
I find the work interesting from a practical and cognitive point of view. Below are my detailed comments, which should be taken into account to improve the quality of the publication:
1. Abstract: The research is quite extensive, I suggest making the abstract more detailed with more results.
2. Chapter 1: What must be the percentage share of surfaces to the development area for the UHI effect to occur. I propose to clearly emphasize what is the greatest achievement of the work.
3. Chapter 2: When discussing tests, please state how many samples were tested each time.
4. Chapter 2.1: Has it been analyzed how the w/c ratio could have changed due to cement from RA?
5. Chapter 3: Please be consistent - either we give results to three significant places in each graph, or we don't do it anywhere. The results are very interesting, it is puzzling whether ettringite is formed during wetting and drying, causing damage to the concrete structure? The permeability of concrete makes it easy for aggressive substances to penetrate. Has the progress of sulphate or chloride corrosion been analysed? The same doubt also applies to the effect of low temperatures.
6. Chapter 4: Please provide directions for further work.
Author Response
Thank you for your thoughtful and constructive feedback on the manuscript. I appreciate your insights and suggestions on how to improve the quality and clarity of the research presented in the article. (All changes are marked in red in the revised version).
Please see the attachment file that provide a point-by-point response to the reviewer’s comments
Author Response File: Author Response.pdf
Reviewer 7 Report
This paper is well written and the topic of this paper is interesting to me. However, there are a few questions that deserve to be resolved.
1. In the abstract, what is RA? It’s better to write the full description of this term.
2. There is a blank page on page 11. Please correct it.
3. As reported in the paper, the recycled aggregates tends to have a relatively lower compressive strength. I am wondering if this compressive strength can satisfy the pavement’s requirements?
4. Have you considered the effects of water to cement ratio? This is another factor that affects the permeability of concrete?
5. Please consider to cite the following articles as they are good for this paper.
Bamforth, P. B. "The water permeability of concrete and its relationship with strength." Magazine of Concrete Research 43.157 (1991): 233-241.
Chia, Kok Seng, and Min-Hong Zhang. "Water permeability and chloride penetrability of high-strength lightweight aggregate concrete." Cement and concrete research 32.4 (2002): 639-645.
Yu, Tzuyang, et al. "Subsurface moisture characterization for sustainable concrete structures using imaging radar." AIP Conference Proceedings. Vol. 2102. No. 1. AIP Publishing LLC, 2019.
Chen, J. J., A. K. H. Kwan, and Y. Jiang. "Adding limestone fines as cement paste replacement to reduce water permeability and sorptivity of concrete." Construction and Building Materials 56 (2014): 87-93.
Author Response
Thank you for your thoughtful and constructive feedback on the manuscript. I appreciate your insights and suggestions on how to improve the quality and clarity of the research presented in the article. (All changes are marked in red in the revised version).
Please see the attachment file that provide a point-by-point response to the reviewer’s comments
Author Response File: Author Response.pdf
Reviewer 8 Report
This paper investigate the hygric properties of water-retaining pervious concrete. The amount of experiments is very large, and the research content is very rich. However, the author seems to have too little intention in writing the article, and still needs to improve the details of the article.
1、The introduction does not clearly explain the research objectives and significance. It is suggested to start from the perspective of environmental protection, next describe the UHI effect and resource shortage respectively, summarize the current research hotspots, and finally highlight the importance of this study.
2、Please check the citation format of references. Such as line 39, 189, 441, etc. Please revise other similar questions together.
3、Please check the unit writing format. Such as line 109 (kg/m3 should be modified as kg/m3), line 86, etc. Please revise other similar questions together.
4、It is suggested to supplement the source of RA, obtained from buildings or roads?
5、It is recommended to delete the data label of the histogram in Figure 4.
6、Please carefully check the layout of the article to avoid blank pages （Page 11）.
7、This paper mainly studies recycled aggregate, but it can not directly obtain research information from the title of the paper. Therefore, it is suggested to modify the title of the article.
Author Response
Thank you for your thoughtful and constructive feedback on the manuscript. I appreciate your insights and suggestions on how to improve the quality and clarity of the research presented in the article. (All changes are marked in red in the revised version).
Please see the attachment file that provide a point-by-point response to the reviewer’s comments
Author Response File: Author Response.pdf
Round 2
Reviewer 7 Report
This paper can be accepted on the present version.
Reviewer 8 Report
I have reviewed the revised manuscript and I'm satisfied that the author has addressed all my concerns in a thorough and thoughtful manner. The manuscript has been significantly improved as a result of their revisions, and I believe it is now of publishable quality.
