Influence of Water-Binder Ratio on the Mechanical Strength and Microstructure of Arch Shell Interface Transition Zone

Round 1

Reviewer 1 Report

The comments on the Manuscript namely “Influence of Water-binder Ratio on the Mechanical Strength and Microstructure of Arch Shell Interface Transition Zone” are mentioned below:

1. Some grammatical errors in the manuscript need to be removed. Please proofread the manuscript.
2. Authors should add the content of the coarse aggregates used for the different mixes of the lightweight ultra-high performance concrete.
3. What is the loss of ignition of the cement during the testing of the chemical composition of cement?
4. Why water reducer was kept constant for each mix?
5. The mix proportions for different mixes should be illustrated in kg/m³ in Table 3.
6. The latest literature is missing from the manuscript. Authors may add the necessary literature.

Author Response

Thank you for your helpful comment on our paper. The  improvements made in the revised text are marked in blue.

Author Response File: Author Response.pdf

Reviewer 2 Report

The article is devoted to the influence of water-binder coefficient on selected properties of interface transition zone. The research described in the paper is interesting and the article is written in a concise and informative way. There are some typos in the text, but I assume that they will be corrected by the editors before publication, so I will not point them out here. However, I found a more serious mistake in the article and I hope that it is just a mistake and not the result of intentional action. Well, in Figure 5, in both its parts, two of the XRD patterns (for w/c = 0.2 and for w/c = 0.18) are identical. I must admit that this very unusual double mistake made me think that maybe this is not the work of chance. But I leave that for the editors to judge. A much smaller shortcoming is that in the figure mentioned above the authors inconsistently used the designation "w/c" instead of "w/b".
I also have some doubt about the conclusions of the study. The authors believe that their results entitle them to conclude that the use of prewetted lightweight aggregate can produce high strength lightweight concretes. In my opinion, it is far too early for such a conclusion. Firstly, it is not clear how the results obtained would translate into concrete compressive strength. Secondly, mixes with a very low w/b ratio and high cement content were made. When making concrete of such a composition (with very limited aggregate size variation), one can expect problems both in terms of technology - obtaining appropriate consistency, as well as potentially high value of shrinkage (the amount of cement per 1 m^3 would be about 600 kg). I would like the authors of the paper to comment on these objections in their paper. I think it would also be advisable to carry out similar tests at higher, closer to reality, values of w/b coefficient. Then the application value of the presented research would surely be much higher. But maybe this should be a subject for another publication. 

Author Response

Thank you for your helpful comment on our paper. The improvements made in the revised text are marked in blue.

Author Response File: Author Response.pdf