Stability Analysis of Tunnel Surrounding Rock When TBM Passes through Fracture Zones with Different Deterioration Levels and Dip Angles
Round 1
Reviewer 1 Report
The paper investigated the stress and deformation of tunnel surrounding rock in urban subway construction based on an actual engineering project. The authors conducted simulation tests to study the effect of fracture zones with varying degrees of deterioration and dip angles on the stability of surrounding rock during the excavation of double-shield TBM. The research method and result data of this study are rigorous and detailed which can provide valuable reference and guidelines for tunnel construction projects through fracture zones. I think the manuscript is well-written with clear structure and it merits to be published. Some suggestions and questions are given below.
1. In the introduction section, please highlight the specific contribution and potential practical significance of this study.
2. In the introduction, in the sentence of "The other researchers have also 78 carried out experimental and numerical research for different fracture strata under various conditions", it is recommended to write as "experimental, analytical, numerical and in-situ research" to include more research in this area. Also, at the end of this sentence, the following reference (10.1007/s00603-022-03160-8) is recommended to be added to support this.
3. In the engineering survey section, please clarify the impact of the physical and mechanical properties of various strata on tunnel construction.
4. In section 3, further analysis and explanation of the results are recommended in comparison with previous studies.
5. In section 5, please provide a clear and concise summary of the main findings.
6. In section 5, please provide additional explanations and clarifications for the simulation assumptions used in this study.
Author Response
Response to Reviewer:
- In the introduction section, please highlight the specific contribution and potential practical significance of this study.
Thank you for your constructive feedback. We have carefully revised the introduction section and highlighted the specific contribution and potential practical significance of our study. We hope that these revisions have improved the overall quality of our paper.
- In the introduction, in the sentence of "The other researchers have also 78 carried out experimental and numerical research for different fracture strata under various conditions", it is recommended to write as "experimental, analytical, numerical and in-situ research" to include more research in this area. Also, at the end of this sentence, the following reference (10.1007/s00603-022-03160-8) is recommended to be added to support this.
Thank you for your valuable feedback on our paper. We have thoroughly reviewed the literature and included recent studies relevant to our study.
- In the engineering survey section, please clarify the impact of the physical and mechanical properties of various strata on tunnel construction.
Thank you for your valuable feedback. However, after careful consideration, we decided to include these clarifications in section 2.2 ("Mechanical Parameters of Materials and Boring Steps"), as we believe this is a more appropriate section to show the specific technical details of tunnel construction related to this topic. The relevant information of various strata was summarized in Table 1.
- In section 3, further analysis and explanation of the results are recommended in comparison with previous studies.
We have carefully considered your suggestion and have made the necessary revisions in Section 3. Compared to previous studies, we have provided a more detailed analysis and explanation of our results.
- In section 5, please provide a clear and concise summary of the main findings.
Thank you for your valuable feedback. We have revised this section (now section 6 in the revised version) to include a clear and concise summary of the main findings of our study.
- In section 5, please provide additional explanations and clarifications for the simulation assumptions used in this study.
Thank you for your insightful feedback regarding our paper. We have revised and included the additional explanations and clarifications of the simulation assumptions in a separate discussion section (now section 5) in the revised manuscript. The previous conclusion section has been moved to section 6. We hope these revisions will better convey our research methodology's details and provide readers with greater clarity.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
The research contributions of the paper should be articulated more clearly.
· Generally speaking, this manuscript contains quite limited new contributions to the Stability analysis of tunnel surrounding rock when TBM passes through fracture zones with different deterioration levels and dip angles. The findings in the manuscript are well documented in previous literature in recent years.
· The introduction section needs a major revision. It has to be corrected and deeply discussed, considering other studies in the literature. It should include recent studies.
- Anato, N.J., Assogba, O.C., Tang, A., Youssouf, D. 2021 .Numerical Investigation of Seismic Isolation Layer Performance for Tunnel Lining in Shanghai Soft Ground ; Arabian Journal for Science and Engineering
- X.H. Bao, Z.F. Xia, G.L. Ye, Y.B. Fu, D. Su; Numerical analysis on the seismic behavior of a large metro subway tunnel in liquefiable ground Tunnelling and Underground Space Technology, 66 (2017), pp. 91-106
- Hamrouni, A.; Sbartai, B.; Dias, D. Ultimate dynamic bearing capacity of shallow strip foundations—Reliability analysis using the response surface methodology. Soil Dyn. Earthq. Eng. 2021, 144, 106690.
- Do NA, Dias D, Oreste P, Djeran-Maigre I. Behaviour of segmental tunnel linings under seismic loads studied with the hyperstatic reaction method. Soil Dynam Earthq Eng 2015;79:108–17.
· Rock is modeled as an elastic-perfectly plastic material with the Mohr-Coulomb failure criterion. Young's modulus and Poisson's ratio of stratigraphic and TBM are taken as constants. It is well known that rock behavior is highly nonlinear, and that prediction of rock motion due to loading cannot be easily achieved by such a simple model with constant deformation parameters.
· in the 4th part (figure 8), fracture zone is modeled with graduations which greatly influences the results, please redo the model with straight lines
Author Response
Response to Reviewer:
- The introduction section needs a major revision. It has to be corrected and deeply discussed, considering other studies in the literature. It should include recent studies.
Thank you for your valuable feedback on our paper. We have taken your comments regarding the introduction section seriously and made significant revisions to address your issues. We have thoroughly reviewed the literature and included recent studies relevant to our study. We hope that these revisions have improved the overall quality of our paper.
- Rock is modeled as an elastic-perfectly plastic material with the Mohr-Coulomb failure criterion. Young's modulus and Poisson's ratio of stratigraphic and TBM are taken as constants. It is well known that rock behavior is highly nonlinear, and that prediction of rock motion due to loading cannot be easily achieved by such a simple model with constant deformation parameters.
Thank you for reviewing our paper and providing valuable feedback. We appreciate and acknowledge your points regarding the limitations and complexities of using an elastic-perfectly plastic model in rock mechanics modeling and the nonlinear behavior of rock.
In our study, we chose this model because it has been widely used in many practical situations and proven effective in previous studies. However, we recognize that this model cannot fully reflect the complex behavior of rock and its variations in deformation parameters, which is an aspect we need to improve further. We have added the additional explanations and clarifications of this simulation assumption in a separate discussion section (now section 5 in the revised manuscript). We hope these modifications will better clarify the methodology details of our study and provide readers with greater clarity. To further enhance our study, we will explore more complex models in future research works and model different types of rocks and strain conditions in more detail and accuracy.
- in the 4th part (figure 8), fracture zone is modeled with graduations which greatly influences the results, please redo the model with straight lines
Thank you for your attention to detail. We have made the necessary changes to address the issue you raised regarding modeling the fracture zone in the 4th part (figure 8). We have now re-done the model with straight lines, as suggested.
Author Response File: Author Response.pdf
Reviewer 3 Report
re-write 1st sentence of abstract.
Author Response
Response to Reviewer:
re-write 1st sentence of abstract.
Thank you for your valuable feedback on our study. We have made the necessary changes and hope that the revised version effectively and concisely captures the essence of our study.
Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report
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