Influence of Combined Action of Steel Fiber and MgO on Chloride Diffusion Resistance of Concrete
Round 1
Reviewer 1 Report
This paper is a study on the improvement of mechanical strength and reduction of chloride permeability by mixing MgO and steel fibers in cement binder. The experiment was conducted with proper composition and process, and it contains contents that would be interesting to readers of the journal. I recommend the publication with minor revision:
(1) In Fig. 3, it is believed that the slump test was also conducted in the present study. Could you please write the corresponding results for each specimen together?
(2) The author did the tensile test with reference to the Chinese standard, but finding the standard is not easy for international researchers. It would be helpful for readers' understanding to describe the details of the experiment as much as possible (load speed and the exact position of load, etc.).
(3) For the porosity test, simple results are addressed, but the analysis of the mechanism of the results is insufficient. Why did macro pores for (>1000 nm) 8%MEA increase? It would be nice to mention this in the last session. The results of the 8%MEA specimen in Fig. 8 are rather awkward. What are your thoughts on this?
(4) The tensile strength of steel fiber is 520 MPa and the content of MgO is 8%. Their numbers are not common values. Is there any reason to choose this material combination? I would be grateful if you could include related references.
Author Response
Thank you for your review of our article. Your suggestions are very helpful to our research, and we have carefully
revised and explained each of your opinions. The specific content is in the attachment. If you think that our research still needs to be further revised, you are
welcome to criticize and correct.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Number of specimens for each type and age of test to be stated.
Variability to be indicated on bar graphs - I bar.
Compressive strength of concrete to be included, if available.
Table 2: with increasing fibre content, the amount of materials for each cubic metre will change (hence kg/m3 need to be adjusted)
Line 109: the word "abrasives" is incorrect and to be amended
Author Response
Thank you for your review of our article. Your suggestions are very helpful to our research, and we have carefully revised and explained each of your opinions. The specific content is in the attachment. If you
think that our research still needs to be further modified, you are welcome to
point out the problem.
Author Response File: Author Response.pdf
Reviewer 3 Report
The paper is addressing an interesting topic and the authors presented it well. There are some gramatical issues that need to be addresses. Technically, the following comments have to be addressed:
Line 13, i think the word invented should be changed.
Line 17, MPI should be replaced by MIP
Line 23 through 25, at this point, the reader does not know what the symbols represent. The authors should present the effect by talking about the mix differences not the mix names.
Lines 37 and 38, change chlorine ions to chloride ions.
Table 2, it appears that the authors added MgO to the mix without reducing any other materials and thus the product will not be one cubic meter, is there an explanation for this approach?
Line 107, why was the split tensile test done on cubes not cylinders?
Line 109, the word abrasives seems to be misused.
Line 166, when talking about ductility, this would be better supported by stress-strain curve if available.
why is 8% MEA so different
how many replicates were made for each test?
Author Response
Thank you for your review of our article. Your suggestions are very helpful to our research, and we have carefully revised and explained each of your opinions. The specific content is in the attachment. If you
think that our research still needs to be further modified, you are welcome to
point out the problem.
Author Response File: Author Response.pdf
Round 2
Reviewer 3 Report
The paper was enhanced and all my points were addressed
Author Response
Thank you for your comments on our paper. Your comments help us a lot.
