Round 1

Reviewer 1 Report

This work presents a study on the electrical and thermal properties of mortar reinforced by carbon fibers. Base on experimentally measured resistance and temperature values, the electro-thermal behavior of the reinforced mortar is investigated. In general, the methodology and presentation of the study are reasonable, the obtained results are interesting.

 

The format of this work may not fully fit the requirements of the journal, for example the tables are not properly aligned yet. Please revise.

 

Some detail comments are as follows:

 

 

Ÿ   What are the mixture designs of the mortars? Are they also the same as REF [12] ?

Ÿ   Please indicate how were the samples dried before and after the flexural test. The water content may have impact on the resistance and thermal tests. 

Ÿ   Line 256, should be table 2 not table 1. The format of the units are chaotic in this table. Please make them uniform.

Ÿ   Line 268, ”…that the conductivity of the prisms is originated by the fibers” this is doubtful. Indeed, the fibers decreases resistance, while normally plane mortars are also conductive. If the only origin is the fibers, it means that all fibers in the samples are connected, in this case the resistance of all specimens should be the same, as the resistivity of the fibers is a constant value.

Ÿ   Fig4, please add a temperature scale

Ÿ   Table 3, if there is no remark, it needs to be removed.

Ÿ   Figure7, please indicate what does the x axis and y axis mean in each figure. And the 1.5% figures are very vague, please improve the quality.

Ÿ   Line 556, “the temperature gaps between different percentage prisms are slightly increasing as the heating time increases” this is not very clear, for example 0.5% and 1%; or 1.5% and 2%.

Author Response

Dear:

Thank you for the helpful comments from reviewer.

We revised our manuscript according to the reviewer’ comments.

Our response to reviewer’s comments is given below.

Thank you!

Jung-Young Son

==========================================

Ÿ   What are the mixture designs of the mortars? Are they also the same as REF [12] :

The design was followed the Korean standard in Reference 11 and it is the same as described at Ref [12].

Ÿ   Please indicate how were the samples dried before and after the flexural test. The water content may have impact on the resistance and thermal tests.

It was stored on my lab. We consider that the samples are completely dried because the plane mortar prisms that were stored together with the samples revealed that their resistances are exceeding our multimeter(Fluke’s handheld)’s measurement range.

Ÿ   Line 256, should be table 2 not table 1. The format of the units are chaotic in this table. Please make them uniform.

Thanks. I corrected and revised to make it uniform.

Ÿ   Line 268, ”…that the conductivity of the prisms is originated by the fibers” this is doubtful. Indeed, the fibers decreases resistance, while normally plane mortars are also conductive. If the only origin is the fibers, it means that all fibers in the samples are connected, in this case the resistance of all specimens should be the same, as the resistivity of the fibers is a constant value.

Thank you for your sharp comment. But I consider that you missed four actual facts described in our text: 1) our sample prisms is nor a normal prism which has a certain amount of moisture, as we described in our text. They are completely dried because the resistances of plane prisms have the resistance values exceeding our multimeter measurement range, 2) each fiber strand has the average diameter of 7㎛ or so, 3) the fibers are randomly distributed in the mortar. and 4) the fibers are covered with cement powers with sands. These means that the fibers in the prisms are also randomly contacted. They are not serially connected to each other for most cases. Prisms with more fibers will have more chances of contacting each other, i.e., the contacting areas are increasing. So fibers has the same resistivity but their different contacting areas makes resistances values different. This is why the resistances of the prisms with different amount of the fibers are different from each other and prisms with more fibers have smaller resistances as shown in Table 2.

Ÿ   Fig4, please add a temperature scale:

Added.

Ÿ   Table 3, if there is no remark, it needs to be removed.

Revised

Ÿ   Figure7, please indicate what does the x axis and y axis mean in each figure. And the 1.5% figures are very vague, please improve the quality.

Our mistake. X and Y axes are specified and 1.5 % scales are cleared.

Ÿ   Line 556, “the temperature gaps between different percentage prisms are slightly increasing as the heating time increases” this is not very clear, for example 0.5% and 1%; or 1.5% and 2%.

This sentence is revised as “the temperature gaps between the 0.5 % and 1.0 %, the 1.0 % and 1.5, and the 1.5 % and 2.0% becomes almost constant, increasing and saturating, respectively, as the heating time increases”.

 

 

Reviewer 2 Report

This manuscript investigated the electro-thermal property of carbon fiber reinforced mortar prism with different fiber contents. The resistance and temperature change were studied, and the prism showed improved conductivity and electro-thermal property. The following minor revisions should be made.

1. The densities of carbon fiber and conceret should be presented.

2. What grade carbon fiber was used in this research?

3. Some samples show the big difference of conductivity. The authors must provide the microscopic morphology of the cross section.

4. The presented method seems practical. I suggest the author to compare the cost before and after introducing carbon fiber.

5. The caption of table 1 is not correct. It should be the mass but not the resistances. There are two table 1.

Author Response

Dear:

Thank you for the helpful comments from reviewer.

We revised our manuscript according to the reviewer’ comments.

Our response to reviewer’s comments is given below.

Thank you!

Jung-Young Son

----------------------------------------------------------------------

1. The densities of carbon fiber and concrete should be presented.

I added the following sentence in our text:

“The weight of the plane prisms allows estimating the density of the plane prisms. It is calculated as 1,804.69 Kg/m³. This density value is almost the same as that of the fiber (Toray (Japan)’s intermediate modulus type T1100G), which is specified as 1,800 Kg/m³. The density value of the plane prisms also implicitly indicates that they lost most of their moisture.

2. What grade carbon fiber was used in this research?

We used Toray (Japan)’s intermediate modulus type T1100G.

3. Some samples show the big difference of conductivity. The authors must provide the microscopic morphology of the cross section.:

It is shown in our reference [15].

4. The presented method seems practical. I suggest the author to compare the cost before and after introducing carbon fiber.

Thanks. But it will be a very difficult task for us now. We made only samples. We spent several hundred more for the carbon fiber compared with the plane prisms.

5. The caption of table 1 is not correct. It should be the mass but not the resistances. There are two table 1.

Thanks. It was changed to weights and the 2nd Table 1 is changed to Table 2.

 

Laura Fay and Karalyn Clouser, Alternative Methods for Deicing, The Western Transportation Institute of Montana State University Bozeman, MT, Project 1003322/CR18-05 May 2020

 

1. Snow melting system by type (Hydronic and Electric), by application (Residential, commercial and municipal): global industry perspective, comprehensive analysis and forecast (Zion Market Research Report 2018. 03), (Accessed 27 August 2020)
2. Chi, T. Yiqiu, Ye. Qing, Long-term thermal analysis of an airfield-runway snow melting system utilizing heat-pipe technology. Energy Convers Manag 186, 473–486 (2019)

he global Snow Melting System Market accounted for USD 5.71 Billion in 2020 and is expected to reach USD 7.95 Billion by 2028, growing at a CAGR of 4.1% from 2021 to 2028.    

 

 

their impairment on the vehicles, roads, and environment in long term is indisputable.

Cold Regions Science and Technology

Volume 160, April 2019, Pages 128-138

Electrical resistance heating for deicing and snow melting applications: Experimental study

Reviewer 3 Report

Dear Authors,

 

Please find enclosed comments.

 

Yours sincerely,

Reviewer

Comments for author File: Comments.pdf

Author Response

Dear Reviewer:

Thank you for the helpful comments.

We revised our manuscript according to the reviewer’ comments.

Thank you!

Jung-Young Son

Author Response File: Author Response.pdf

Round 2

Reviewer 3 Report

Dear Authors,

I read the responses to the reviews and noticed that in the revised version of the article, the authors corrected the errors and did not mark some of the corrections in the text.

 In my opinion captions under the figures should be concise, and any additional descriptions (comments) to these figures should be placed in the text.

For example, there is:

 “Figure 7. The waveforms of temperature distribution patterns along the vertical bisect lines: The vertical and horizontal axes represent temperature and pixel numbers from top to bottom of the vertical bisect line, respectively.”

and description:

“The vertical and horizontal axes represent temperature and pixel numbers from top to bottom of the vertical bisect line, respectively.:

should be included in the text.

So please correct these minor errors.

After making these corrections, I accept the answers and the article.

Best regards,

Reviewer

Author Response

Dear Reviewer:

 

Report : 

I read the responses to the reviews and noticed that in the revised version of the article, the authors corrected the errors and did not mark some of the corrections in the text.

 In my opinion captions under the figures should be concise, and any additional descriptions (comments) to these figures should be placed in the text.

For example, there is:

 “Figure 7. The waveforms of temperature distribution patterns along the vertical bisect lines: The vertical and horizontal axes represent temperature and pixel numbers from top to bottom of the vertical bisect line, respectively.”

and description:

“The vertical and horizontal axes represent temperature and pixel numbers from top to bottom of the vertical bisect line, respectively.:

should be included in the text.

So please correct these minor errors.

After making these corrections, I accept the answers and the article.

 

Reply :

I don’t know what is wrong in our description?

Can you indicate more specifically why do you think our expression is wrong?

We consider that our expression is proper.

 

Best regards,

Jung-Young Son