Improving Structural Performance of Reinforced Concrete Beams with Phragmites Australis Fiber and Waste Glass Additives
Round 1
Reviewer 1 Report
This paper deals with the performance evaluation of reinforced concrete beams with Phragmites-Australis fibers and waste glass additives.
The paper contains all the necessary data that will ensure the reproducibility of the research. The paper clearly states the norms according to which the samples were made and according to which the testing was carried out.
I think that the conclusion is concise and that it gives an overview of the most important results obtained from the research.
The literature review is very extensive.
Despite what was written earlier, the Authors should address the following issues in order to increase the quality of the manuscript:
Line 139: "...cut into 3 cm lengths and 2 cm widths using..." Please explain why and how that specific length and width was chosen.
Line 142: "...a 24-hour chemical treatment using NaOH was applied to these fibers.." Please explain in the manuscript why such a treatment was chosen. Was it carried out according to other literature or according to some norm.
I believe that Figure 1 does not show "the transformation", but the pieces of glass are shown on the left, while the fine aggregate/particles are shown on the right.
In Figure 3, the diagram for cement needs to be shown in a different color (e.g. black), because gray is very difficult to recognize with auxiliary lines.
The title of Figure 4 and 6 needs to be edited. Colons and commas are used incorrectly in the title. kindly ask the Authors to fix it.
In the title of Figure 5, it is necessary to write the units of measurement.
I think that the views in Figure 6 need to be rotated (aligned) because the slanted views give the impression that something is uncertain, strange or confusing.
The text in Figure 14 should be enlarged so that it matches the surrounding text in the manuscript. The font in the figure is too small.
Author Response
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Author Response.docx
Reviewer 2 Report
The article aims to investigate the effect of incorporating waste glass as a cement replacement with natural fibers from the Phragmites Australis plant on the performance of reinforced concrete (RC) beams. The experimental activity was well-conceived and performed correctly. Nevertheless, some issues are not correctly addressed, and the article needs revisions before being suitable for publication. Some detailed comments are provided below:
· Lines 77-84: Is there any more research regarding the addition of PA fibers in concrete? I mean, did any article analyzed the strength or any other property of those materials?
· Lines 130-131: What is the chemical composition of the cement?
· Lines 135-136: What is the absorption of the aggregates? This is an important value that can affect the properties of the final material.
· Line 200: Figure 4 does not really add anything to the article. I would remove it.
· Lines 236-248: I do not think that these results are showing big changes. The authors did modify the y-axis, and the drops seem higher. Nevertheless, the “decrease” in density is lower than 0.83% (compared to the reference value). Therefore, we could say that the density of all mixtures is almost the same.
· Line 250: How many samples were tested? What is the standard deviation? This must be included in Figure 7. One sample is not enough to obtain meaningful data. Same comments for Figures 8-11.
· Lines 286-290: Is there a good correlation between UPV and compressive strength? Authors should show this correlation to justify this observation.
· Figure 12: Are these graphs related to flexural strength tests? This should be clear in the manuscript.
· Table 2: Add the units of all the columns.
· Lines 234-444: I miss more discussion of the results.
· Lines 445-470: The conclusions are simply an overview of the observations of the tests. Please add part of the main points of the discussion.
Author Response
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Reviewer 3 Report
1) Avoid mass citation, e.g. "[6-11]" in line 48, "[12-20]" in line 51 or especially "[30-46]" in line 98, etc. The mass citation does not give any value or content to the paper only increasing the number of references. These citations are never referenced back in the paper, authors put them after general sentences. I suggest to rewrite these sentences and break the citations into categories at least the referenced papers.
2) I may advise to put a table into subchapter 2.1. which contains the physical data of the raw materials that authors used in the research and describe the data source as well. Are the properties (e.g. density) measured by authors themselfs or the data is from technical datasheets of the manufacturer of the raw materials? I also advise to include or cite the producer and country, when an exact product is used, e.g. VisoCrete.
3) I recommend using "glass powder" instead of glass in the paper, when referencing the pulverized glass.
4) I may recommend changing grey color in Figure 3 for visibility. Also, I miss a description in the text about Figure 3, as well as the details of the methodology of the sieve analysis done by the authors.
5) I suggest to include the environment conditions (temperature, relative humidity) during mixing, sample preparation, curing (temperature of curing water) and testing in the laboratory.
6) All barcharts shows average values (Fig. 7-11), I recommend adding the error bars showing the standard deviation of the tests.
7) I recommend to unify the aesthetics of the figures containing bar charts. E.g. Figure 8 has now outlines around the bars (although the thickness of the outlines are varying), and the others does not. Figure 11 has shades, and others does not. I recommend having thin outlines around the bars.
8) I recommend adding also some percentage differences, values or indicators referring to specifics in the conclusions.
9) I advise to extend the conclusion chapter with the industrial usability of the results and further research perspectives.
Author Response
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Round 2
Reviewer 2 Report
· Figures 7, 8, 10 and 11: The standard deviations of those figures are not acceptable to draw any conclusions. The authors must repeat the tests to possibly trust the results.
· Lines 234-444: I still miss more discussion of the results. The authors just added two sentences.
Author Response
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Reviewer 3 Report
Thank you for the detailed answers on the reviewers' questions. I may suggest a few things:
1) Remove the outer frame from Figure 15 to unify the aesthetics with all other figures in the paper.
2) Instead of writing "AutoCAD sketch", I advise to use "schematic illustration" in Figure 5. There is no need for adding AutoCAD product name to that figure.
4) Chemical composition of cement in Table 1 does not add up to 100%, there are "other" elements present, which should be represented in an "others" column with their percentage.
5) I may advise writing cement properties in text instead of Table 2, and add unit for water demand as well.
6) In conclusion chapter, the last bullet point should not be bullet point, but simply the last paragraph, since it does not belongs to the conclusions, it presents the practical implications.
7) Reviewer 1 asked about fiber length of PA fibers. It may worth to mention that natural fiber bulks' thermal conductivity is affected by the fiber lenght, e.g. wheat or barley straw's optimal length for insulation purposes is shown to be 1-3 cm: https://www.researchgate.net/publication/344418814_Biodegradable_and_fire-resistant_thermal_insulation_boards_made_of_wheat_straw Reviewer 1 also asked about the NaOH wet fiber treatment, and based on your answer, you may try dry treatment processes on lignocellulosic fibres in the future, e.g. https://doi.org/10.1007/s10973-023-11945-4
Author Response
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