Practical Model Proposed for the Structural Analysis of Segmental Tunnels
Round 1
Reviewer 1 Report
Dear Authors,
Thank you for the paper and interesting study. The paper structure and contents are very well presented. I further, propose the following changes and major revision on the paper and re-consideration of the paper.
Comments:
1- In line 111 and 112 after the authors stated: “firstly, a constitutive moment-rotation equation under constant eccentricity of the axial load is used, with this, it is not necessary to iterate during the analysis”. The question here is could you please clarify why it is not necessary to iterate during analysis and also compare in a previous study where they use iteration but, in your study, not needs for what reasons?
2- From line 111 until 123; you are explaining the main purposes of this study but mainly you are expressing how easy is the model and methodologies beside cost effective! But here I cannot see the main contribution is only is easy to apply? Please explain the methodology and fundamental science question in this study as I see you can propose a new section and re-consider the main purposes and secondary purposes of this study. In my point of view being easy model can be a secondary purpose but how it can help accuracy and precise of the model? Or any new contribution that make this research different from other.
3- In line 179 you are calculating a Mmax and yield rotation but many variables are unknown such as in previous equations 3 and 4; can you please consider adding a new table with all data for an example and show the results with equations in an above inside table? This will make your research more prestige and will help journal prestige as well such as table 2 (mechanical properties of materials).
- In line 218 you are ignoring the damage caused by tensile stress would it be possible to add effects of both tensile and compressive and why this study is only considering compressive caused damages?
5- For me, the paper still needs to discuss the novelty of this research not the only application of the FEM model, what is making your work a unique work? Discussion needs to show more data and results or comparisons if needed?
6- Please, re-consider the conclusion and mention what’s the contribution and innovative outcomes from this research?
7- Figures need to be revised such as Fig.2.a colours are not so convincing for readers, and check others. Fig.5 need separations and defining other parts of the model and lower ring are not considered or why I can’t not see? Please explain this. Check all figures.
8- Please re-write abstract in better form after considering all changes?
After a comprehensive review, I suggest a major revision of the paper and most importantly please consider well-addressing results to support the scientific outcomes from your research work.
Best of Luck!
Saludos cordiales
Comments for author File: 
Comments.pdf
Author Response
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Author Response File: Author Response.pdf
Reviewer 2 Report
In this study, the structural response of a typical tunnel built in soft soil was studied, using a simplified model which consider the coupling between segmental rings. Generally speaking, this paper is well written and can be of interest to the readers of structural engineering. However, there are some problems the authors should look into.
- I am not sure why this manuscript was submitted to the section of Sustainable and Durable Building Materials, since I cannot find any contents about sustainability and durability. Some sustainable building materials should be reviewed. For example, geopolymer (sometimes called alkali-activated materials) has been considered as the third generation of green cementing materials.(e.g., "Evaluation of glass powder-based geopolymer stabilized road bases containing recycled waste glass aggregate. Transportation Research Record, 2674(1), pp.22-32."; "Analytical investigation of phase assemblages of alkali-activated materials in CaO-SiO2-Al2O3 systems: The management of reaction products and designing of precursors. Materials & Design, 194, p.108975."; "Strength, microstructure, efflorescence behavior and environmental impacts of waste glass geopolymers cured at ambient temperature. Journal of Cleaner Production, 252, p.119610." etc.)
- The introduction part should highlight the limitations of previous work and how this study can contribute to a deeper understanding of this problem.
- In the section of Materials and Methods, the authors should explain how they got the experimental results (what kind of tests were performed?) which were used to compare with the modelling results.
- The input information of the modelling are not well described. For example, the density of soil, existing load above the soil, underground water, self-weight etc.
- What assumptions have been made to make it a non-linear FEM? It looks like linear FEM is also feasible.
- The conclusions are too simple. Please highlight the findings and innovations with more descriptions.
Author Response
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Author Response File: Author Response.pdf
Reviewer 3 Report
Interesting reading for practical engineers. For me, the practical impact of this paper is more significant then scientific one.
Paper can be considered as "back to roots" in the field of use FEM for structural analysis, but smarter way, easily available for engineers, not scientist.
Second equation in (2) and (4) should have the same order of used variables, but nothing serious
Author Response
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Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
Dear Authors,
Thank you for answering and modifying all necessary information in your revised version.
From my side, I agree with the publication of the paper in the present form.
best regards
Reviewer 2 Report
This paper has been revised significantly and should be ready for publication.
