Rock Material Recycling in Tunnel Engineering
Round 1
Reviewer 1 Report
The reviewed article shows an interesting idea of recycling of tunnel excavation material on an example of Brenner Base Tunnel. The presented concept seems to be worth a detailed examination. Nevertheless, the reviewer is wondering if the journal Applied Sciences is appropriate for the manuscript. In his opinion, a journal on sustainable development is worth considering.
According to the reviewer, in the presented article, are missing some key issues.
1. The article introduction is incomplete. There is no clear aim. What the authors would like to achieve with this article? Is this a strictly theoretical article? It seems so.
In addition, a significant literature review is missing here. Only a fragment of the first paragraph of the Introduction section may possibly be included in the literature review.
2. Part of the article regarding the Brenner Base Tunnel construction is presented correctly, however, Table 1 needs some supplementing. There is no discussion of the results from Table 1. In addition, it is not known if these are the results of own studies conducted for the purposes of this article? Where was the research done?
The research section is very small and could be improved. For sure, the value of the article will increase.
3. When presenting selected test results, not everything is clear. For readers unfamiliar with the topic, some concepts/parameters may be unknown, e.g., shape index, flakiness index. Please, explain these parameters and give their meaning.
Author Response
Dear Reviewer!
Many thanks for your detailed and constructive feedback to improve the article! I hope the adjustments meet your expectations. The changes in the text were marked grey.
The points highlighted in your review report were modified/improved as follows:
The article is intended for the special issue "Recycling Waste in Construction Materials" of Applied Sciences, therefore the topic of rock material recycling for construction products should meet the content alignment.
1. In the article abstract and introduction, the challenges as well as the clear aim of the article are presented more explicitly.
A more detailed literature review was added into the introduction and the reference list was extended.
2. Additional information for Table 1 is given and is discussed in detail. The research was done in the course of my postdoctoral qualification and is now designated correctly.
The research section was extended regarding the content of aggregate shape characterisation and concrete mix design experimentation (section 4.3 and 4.4) as well as references to the technical standards, giving a more holistic view.
3. Unknown concepts and parameters, like shape index and flakiness index, were explained at the relevant text sections.
Many thanks and best regards
Klaus Voit
Reviewer 2 Report
In my opinion, it si a good paper. Perhaps, the authors should be make the conclusions more specifics.
Regarding the the waste obtained of the excavation with tunnel boring machine, is not neccesary to washed it before the use like aggregates in concrete?
Author Response
Dear Reviewer!
Thank you very much for your positive review!
The conclusions were modified to be more specific regarding the content of the article.
You are absolutely right, washing of the aggregate need to be done during material processing. This information was supplemented in the paper at the corresponding location.
Please find the changes in the paper highlighted in grey.
Many thanks and best regards
Klaus Voit
Round 2
Reviewer 1 Report
Dear authors.
I would like to thank you for all changes to the presented article. Thanks to them, the article has become clearer and certainly reflects the intended purpose better. I agree with all the modifications introduced by the authors and I think that the article in its current form can be published in the special issue "Recycling Waste in Construction Materials" of Applied Sciences.
