Impact Resistance and Flexural Performance Properties of Hybrid Fiber-Reinforced Cement Mortar Containing Steel and Carbon Fibers

Round 1

Reviewer 1 Report

The article is scientifically and research-correct. The description of samples and performed tests is clear and legible. The issues presented are generally known and can be read about them in the literature. The article is therefore a supplement to the information on the subject of mortars and fiber reinforced concretes. It is a pity that the literature review in the introduction is somewhat sparse and the results obtained by other researchers are not presented. The conclusions did not manage to confront the obtained results with the results taken from the literature. Perhaps the literature review and conclusions will be developed.

Author Response

 "Please see the attachment."

Author Response File: Author Response.pdf

Reviewer 2 Report

In this study, the properties such as flexural performance, compressive strength, and impact resistance of MFRCM and HyFRCM were investigated.

From my point of view, the paper is complete, the test design is reasonable, the structure layout is good, and the conclusion is convincing. I suggest some minor modifications in order to make it better:

1.      Figure (2) should be more clear for readers to observe the structure of the two fibers.

2.      Please check 3.1.2 chapter, if the sentence”The reason why the compressive strength increased this way was because the use of CF could reinforce CF which was relatively smaller in size than SF.” is right.

3.      Kan, W.; Yang, Z.; Yu, L. Study on frost resistance of the carbon-fiber-reinforced concrete. Appl. Sci. 2022, 12, 3823. The citation of this document has little relevance to this paper.

 

Author Response

 "Please see the attachment."

Author Response File: Author Response.pdf

Reviewer 3 Report

In this paper, authors assess the impact resistance, the flexural performance and the compressive strength of Fiber-Reinforced cement mortar containing mixes of steel and carbon fibers. The following comments should be considered to improve the quality of the paper:

-          Line 108. Why was water/cement relationship set to 0.46? This is a strange value. This value is usually fixed at the beginning as starting parameter.

-          Line 109. What super-plasticizer was used?

-          Line 127-129. The grammatical construction of the sentence is not correct.

-          Line 169. What authors mean with “domestic regulations”?

-          Line 179, the equation appears wrong in the pdf.

-          Figure 5. The resolution of the figure must be improved.

-          Line 190. The compression tests were performed in too small samples (40 x 40 x 160 mm). The typical design regulations employ 300 mm length and 150 mm diameter cylinders, or 100 mm – 150 mm cubes. Do authors think that the small sample size affects the results?

-          Line 205. This is a very important part of the paper. The explanation of why the combination of different types of fibers is better. Authors should justify much more this explanation and references that endorse authors statements.

-          Line 225. This statements also must be endorsed by citations of other researchers. The size of the fibers in relation to the aggregates can also be a part of the explanation.

-          In general, authors do not justify the explanations of the results properly. This is the most important part of the research and it is not correctly justified.

Author Response

 "Please see the attachment."

Author Response File: Author Response.pdf

Round 2

Reviewer 3 Report

Reviewer thanks authors' response. Nevertheless there are some comments that has not been properly answered. According to the revision document of authors, the following information is missed:

 Question 1: Authors do not respond why that W/C relation has been used.

Question 8: Some citations that endorese the sentence “That is, it is considered that the performance is improved by controlling the rather macrocracks of the relatively long steel fibers while the short carbon fibers control the microcracks.” should be added, as the primal comment suggested.

Question 10: Authors are asked to provide more explanations to the results that they are getting in the current research, not only in the future ones. Therefore, the paper should be enriched with more result justificactions.

 

Author Response

Please see the attachment.

Author Response File: Author Response.docx