Study on Longitudinal Stress Relaxation Effect and Reinforcement Technology of Segment Lining during Shield Docking

Round 1

Reviewer 1 Report

Dear Authors,

The topic you are addressing is interesting because it deals with a serious engineering task. Stress relaxation and reinforcement modeling as a practical guide for planning and applying technology are considered crucial. While the idea of your paper seems clear to me, the paper itself is not. It is not structured well and lacks clear novelty and contribution to the body of knowledge. In the introduction, lines 88-89, you state that the paper ".. provides some theoretical basis for engineering construction." For a scientific or professional paper, this is not an acceptable contribution. You have to be precise with the aim of your paper, and pronouns such as "some," which denotes an indeterminate quantity, are not welcome. Please state the precise contribution of your study. As well, if you are aiming to present the current state-of-the-art, the literature review has to be more comprehensive. On the other hand, if you provide a new modeling approach, you have to precisely state why and how your approach is better than the previous ones. In both cases, the methodology is a crucial part of such papers, and in yours, this segment is missing. The title is awkwardly structured and seems unfinished, or it lacks a noun. The figures are of poor quality and are blurred.

For this first round of review, please be more precise with your paper, and in the second round, perhaps I could provide you with more helpful advice.

Kind regards

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Reviewer 2 Report

The assessed work is interesting  and relatively rarely published work on the topic researches on longitudinal stress relaxation and reinforcement technology of segment lining after shield docking and dismantling. It should be noted that due to the practical difficulty of tunnel construction, it is almost always necessary to treat the topic individually. Many of the solutions used in this area are purely practical, developed on the basis of many years of experience and they are not confirmed by appropriate mathematical models. The authors focused mainly on the methods of theoretical calculation and numerical simulation to study the longitudinal stress relaxation effect of segment lining and steel channel reinforcement technology after the thrust is unloaded in the process of shield docking and dismantling and the obtained results were verified by comparing them by comparing the opening of circumferential joint.

In my opinion, although the final conclusions directly confirm the analyzes and calculations carried out, the very way of describing the issues and adopted models is complicated and difficult to understand, and therefore the number of potential recipients (readers) may be significantly limited. I find it useful (but not necessary) to use simpler and more readable methods to describe the issue.

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

Dear Authors,

I can notice your effort in acknowledging my suggestions in the revised version of your paper, and I thank you for that. However, as I promised, here are my more helpful suggestions:

1. Figures 1-7, 9, 11, 12, and 13-21 are still blurred; the small font size makes them hard to read; if you are aiming to highlight reference lines by color, please do so in a clear manner. 

2. Figure 8, besides its blurriness, is not clear and requires a legend, textual explanation, or scale of the color gradient and highlighted "red and blue line" you are referring to in the text.

3. Figure 10: What are you aiming to present with this figure? It seems that it is a missing segment, as is the case in the previous note.

4. Consider merging graphs in order to reduce the number of figures and make the results comparable.

5. You have 9 references out of a modest 26 total, published in the last 5 years. As I mentioned in the previous round of the review, in order to have a well-backed research gap that you are aiming to fill, the literature review has to be more thoroughly presented; e.g., by using your keywords and their combinations, I managed to find some recent scientific articles that you have neglected.

6. Replacing the sentence "This paper provides some theoretical basis for engineering construction." with the sentence "This paper provides a theoretical basis for shield tunnel segment longitudinal reinforcement technology in the process of docking." does not make your contribution clear nor precise. As such, it better fits in a professional textbook than in a scientific paper. The question from the previous round still stands: why, how, and to what extent does your paper contribute to the body of knowledge?

7. In the conclusion, you structured the results into 4 points. Why are there no four hypotheses, i.e., research questions and anticipations, stated in the paper previously? In this way, it seems that you were surprised by the results and that they appeared spontaneously.

8. You have not presented a clear methodology applied in your study. Without this segment, a paper cannot be qualified as a scientific, or a professional, paper.

9. The parameters presented in tables 1 and 2 have to be referenced as well.

10. The results could be easily presented in a table where they could be comparable. This is what the paper would greatly benefit from, so I strongly suggest that you compress the results in this form. This I would suggest for constants appearing in the text as well.

11. On page 8, line 275, you state, "The contact of the model is optimized." The further text does not explain the objective and constraints of the model optimization. The model itself is an idealization, and the optimized one tends to be highly sensitive. Hence, you should provide a clear sensitivity analysis of the model since you are leaning on the theoretical data. In this perspective, I can suggest a reference. Optimization of a steel penstock with stiffener rings, Electronic Journal of the Faculty of Civil Engineering Osijek-e-GFOS, 2018, 17, pp. 64-73, https://doi.org/10.13167/2018.17.7

Kind regards

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Round 3

Reviewer 1 Report

Dear Authors,

Your paper accurately reflects the revisions. Best of luck with the rest of the publishing procedure.

Best regards

Author Response

Thank you for your valuable suggestions on my paper and wish you all the best.

Kind regards.