Study on Heating Performance and Flexural Strength Properties of Electrically Conductive Mortar

Round 1

Reviewer 1 Report

The article has potential for publication, but some points need to be clarified:

- Abstract: there are some punctuation errors in this section. Also the abstract is very generic and unattractive. Please proofread these sections appropriately, making it clear how your research differs from others published in the same field. In the abstract include the main objectives and the originality of the research.

- Review the sentence: “In particular, more and more studies are being conducted on the conductive fiber-reinforced cement-based composites incorporating conductive materials into existing”.

- Do not use generic quotes. See for example the first paragraph of the article. The authors use 7 citations to present information widely known by authors in the field. The same happens in the second paragraph where the authors use 10 citations to discuss widely known information in the area. Instead, provide more in-depth information about the citations. Explain what is already known about the area and what has not yet been studied, based on the citations.

- In the introduction, one point is very flawed: what are electrically conductive mortars? Although the name is very specific, it is necessary for authors to contextualize this type of material. What are your applications? Advantages and disadvantages? In what situation is this type of mortar recommended? How is it different from conventional mortars? Just using carbon fiber or steel fiber? Are all mortars containing carbon fiber or steel fiber considered electrically conductive mortar? Authors should provide more specific information about this type of material as it is not a conventional mortar.

- What are the differences between this work and other similar research published by the authors? (Effect of Carbon and Steel Fibers on the Strength Properties and Electrical Conductivity of Fiber-Reinforced Cement Mortar). Please clarify the differences and explain why these jobs are different.

- Section 2.2: present the granulometry of the materials used in the research.

- Section 2.3: explain how the compositions studied in the research were defined.

- Section 3.1, 3.2, 3.3: the authors do not use quotes or references in these sections. This is not acceptable in a scientific article. Please compare the results obtained with similar searches. In addition, justify the statements made in this section using appropriate references.

- Figures 6 and 7: the content and quality of the figures is very low, making it difficult to understand the information present in the image. Please improve the quality of these figures in the next version of the article.

- Section 3.4: “In road pavement, flexural strength is the most basic variable in identifying material properties and is a factor for measuring strength.” It is the first time we find this information in the article. It should be very clear that this is the proposed application. Also correlate this application with electrically conductive mortar. Why is this type of mortar necessary for road pavement? Please make it more clear.

- Section 3.4: it should be very clear to the readers what is the effect of the fibers in the studied material. For example, comparing CF and SF, what are the effects of these two fiber types? Another point that needs to be highlighted is the effect of the fiber content in the mortar. It is expected that the higher the fiber content the better the behavior. Why didn't it happen? Is it related to the fiber saturation point, for example? Please justify further.

- Figure 10: include the experimental deviations in the image.

- In mortars (and other cementitious materials) the main mechanical property is the compressive strength. Why is this property not evaluated in the authors' research? Please specify further why these properties were not evaluated in your search.

- Figure 12: improve the quality of the figure and explain what fiber content was used in the test.

- Section 3.5: SEM images must have the same magnification and fiber content to be compared. Note that the ECM-CF composition was evaluated at 500x and 100x magnification, while the ECM-SF composition was evaluated at 150x and 50x magnification. If the increase is not the same, it is impossible to perform the comparison made in this section. Furthermore, I do not believe that it is possible to observe C-S-H and other cement hydration products at 150x magnification. To observe these products the magnification must be above 500x. Therefore, I do not agree with the discussion that took place. Review.

- Figure 13: Was there an increase (or gain) in mass in the test? How is this possible? What justifies the increase in mass observed in the figure in the SF composition? It makes no sense. Please look at the data and see what happens to this material at temperatures above 800°C.

- Review your conclusions based on previous comments.

Abstract: there are some punctuation errors in this section.

Author Response

Submit as an attachment.

Author Response File: Author Response.docx

Reviewer 2 Report

The reviewer recommends taking the following notes into account.

 “many studies have been conducted on electrically conductive heating cement composites and their mechanical properties [1-3].” Many in minds, a few in references.

 The quality of the 6, 7, 8, 9, 10, 11 figures needs to be improved, numbers should be highlighted and enlarged.

 The temperature of which part of the surface of the specimen is shown in Figures 8 and 9?

 „tended to increase proportionally“ ? The reviewer did not find proportionality. Maybe you could clarify.

Author Response

Submit as an attachment.

Author Response File: Author Response.docx

Reviewer 3 Report

The paper "Study on Heating Performance and Flexural Strength Properties of 2 Electrically Conductive Mortar" presents interesting research into the properties of electrically conductive mortar with two types of fibers. Conductive mortars and concretes are a current issue, and thus the paper is of interest. The research is broad, and well described. There are a few issues I would like to point to the authors: 

1. Table 1 is very uninformative and mixes several types of information. There is no need to include the size of the samples in it (there is only one); also the types of tests are not variables. 

2. There is no statistical information about the results obtained, 

3. there is no clear indication of how the consistency was set and tested, 

4. Figures are blurry and hard to read - this may be an issue with saving as .pdf  and might not have a bearing on the final version, but please check that issue. 

Author Response

Submit as an attachment.

Author Response File: Author Response.docx

Reviewer 4 Report

The authors have presented a very interesting paper that deserves consideration for the journal Applied Sciences. Some changes are proposed before acceptance and some reflections are included.

The abstract is very long and should be shortened.

The introduction is very complete and well organised, with very relevant and leading references.

In the experimental plan, include the reference standards used. It is understood that the moulds used are the RILEM standard moulds,

In Table 2, indicate whether the properties of the fibres used have been measured or, if not, give a reference to where the results have been obtained.

The granulometric curve, mortar consistency and porosity of the mixture should be included.

The error of the measurements should be included in the graphs.

The discussion of Figure 12 should be included below the image and not before. Idem, TGA.

Line 511, delete: "We think...", this expression shows opinion and is not an informative article. In addition, the limitations of the study should be included: have the environmental parameters of humidity been considered, has the porosity of the mixture been taken into account?

Finally, and as a future idea, I can advise the authors to replicate a similar study comparing mortars made with mortars made with recycled sands. The latter will require more mixing water and the variations could be more significant.

Author Response

Submit as an attachment.

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

The authors revised the comments of the previous version. So my decision is: accept the article for publication.