Bond Strength Properties of GFRP and CFRP according to Concrete Strength
Round 1
Reviewer 1 Report
The authors investigated the bond strength by using the water-cement ratio as the variable, based on ASTM C 234, and got some conclusions, such as lower water-cement ratio led to higher compressive strength as well as bond strength, and the bond strength of GFRP was about 23% lower than that of CFRP. It is an interesting work. The reviewer has several questions to be considered in minor revision before this paper can be published.
-What is the advantages of the proposed method? Please give some quantitative analysis by comparison.
-Paper subject is interesting, but scientific contribution and novelty of the paper should be showed with results with explanations. Results are not informative. Comparisons are not enough.
-The introduction does not analyze enough the existing literature on the specific topic: there is no clear claim about what is original compared to what has been done by others on the same matter.
-The reference part has to be improved a lot by adding more very recent references, for example, DOI: 10.14359/51732989, DOI: 10.1016/j.conbuildmat.2020.118048, DOI: 10.3390/ma12182958, and DOI: 10.1007/s10163-019-00922-5.
-Please double check the English expressions.
Author Response
Please see the attachment.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
The paper presented an experimental investigation of the bond strength performance of Glass and Carbon fiber-reinforced plastics (GFRP and CFRP) bars with concrete materials that have varied water-cement ratios (varied compressive strengths). However, before the final decision, the authors need to address the following comments:
1. The Abstract is quite general, the main problem statement and objective of this research need to be discussed and presented in a better version.
2. The background and literature in the introduction section must be further improved by discuss additional references within the scope of the current study; specifically those published in the latest five years. The presented literature was prepared based on old and very limited references, where only 1 paper from total 13 references is within the latest 5 years, which is Ref. [9].
3. The research gap and objective of this research should be clearly highlighted and discussed in the introduction.
4. The technical writing of the results discussions must be improved to properly justify the objective of this research. For example, need to discuss scientifically the reason why CFRP bars achieved higher bond strength than the GFRP bars for the same concrete mixture (strength)?.
5. The conclusions are too general, and the limitation of the current study should be clearly highlighted.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report
The authors addressed most of the given comments and the revised paper is improved.
However, the last 4 references [20-23] in the updated list are not cited in the sections of the paper (Introduction, experimental procedure, and/or results and discussion). !!!
This matter is very compulsory, where all listed references must be mentioned and cited in the related sentences in the sections of the paper.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
