Numerical Simulation of the External Water Pressure in Seepage Anisotropy Under Heterogeneous Conditions
Round 1
Reviewer 1 Report
Comments and Suggestions for Authors1. What is the main question addressed by the research?
The paper tackles the parameters on the infiltration of the tunnel on external pressure numerically.
2. What parts do you consider original or relevant to the field? What
specific gap in the field does the paper address?
The paper suffers from lack of originality in scientific methodology and results.
3. What does it add to the subject area compared with other published
material? It does not add very much to the field and the journal.
4. What specific improvements should the authors consider regarding the
methodology? What further controls should be considered?
The authors should justify their method used. Why do they use this method? Then, the governing equations, the numerical method used, the mesh and the boundaries should be discussed.
5. Are the conclusions consistent with the evidence and arguments presented? Were all the main questions posed addressed? By which specific experiments?
More numerical results and deeper comparison with the literature are necessary.
6. Are the references appropriate? The literature review is poor.
7. Any additional comments on the tables and figures and the quality of the
data. No more comments.
The language needs to be improved. It is written in a very poor way.
Author Response
Point 1: What is the main question addressed by the research?
The paper tackles the parameters on the infiltration of the tunnel on external pressure numerically.
Response 1: For the heterogeneous soil layer and seepage anisotropy, numerical simulations are employed to examine how composite lining parameters affect the tunnel’ external water pressure.
Point 2: What parts do you consider original or relevant to the field? What specific gap in the field does the paper address?
The paper suffers from lack of originality in scientific methodology and results.
Response 2: In the process of tunnel construction, external water pressure is an important load that should be considered in the design of tunnel lining structure. Especially in the water-rich area, the design value of external water pressure determines the strength of lining structure, which has a far-reaching impact on tunnel construction and operation safety. At present, there are generally three kinds of waterproof and drainage methods for composite lining tunnels : full plugging type, full drainage type and water plugging and limited drainage type. In the full water plugging scheme, the tunnel lining bears all the water pressure, and the excessive water pressure will cause the designed lining to be too thick. The full drainage scheme basically does not consider the water pressure in the design, which can make the lining structure more economical, but the excessive drainage will affect the surrounding ecological environment. In contrast, the water plugging and drainage limiting scheme by increasing the grouting ring can not only reduce the external water pressure of the lining, but also will not have a great impact on the environment. It is increasingly used in high water pressure tunnels. Based on the No.1 tunnel of Xiaolangdi project, this paper analyzes the influence of composite lining parameters on external water pressure under the action of heterogeneous surrounding rock and seepage anisotropy.
Point 3: What does it add to the subject area compared with other published material? It does not add very much to the field and the journal.
Response 3: We have considered the geological conditions of the location of the tunnel, which is a heterogeneous stratum of mudstone interbeds , the influence factors of surrounding rock lithology, drainage or grouting measures on the external water pressure of tunnel lining.
Point 4: What specific improvements should the authors consider regarding the methodology? What further controls should be considered?
The authors should justify their method used. Why do they use this method? Then, the governing equations, the numerical method used, the mesh and the boundaries should be discussed.
Response 4: Thank you for pointing out this suggestion. Because of the time schedule, we will further consider the control measures and theoretical research on external water pressure in the next article.
Point 5: Are the conclusions consistent with the evidence and arguments presented? Were all the main questions posed addressed? By which specific experiments?
More numerical results and deeper comparison with the literature are necessary.
Response 5: Thanks for your valuable suggestion. The conclusions and arguments we get are consistent. We have modified it according to the comment.
Point 6: Are the references appropriate? The literature review is poor.
Response 6: We have modified it according to the comment. We reorganized the introduction part.
Point 7: Any additional comments on the tables and figures and the quality of the
data. No more comments.
Response 7: We have modified it according to the comment.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsMinor revise：
1. The formula and parameter part: the text and the variables and parameters mentioned in the formula give an explanation when they first appear, and the variables are in italics.
2. The annotation method of references in this journal adopts sequential coding system, referring to the manuscript template of this journal.
3. The figure in the text should appear with the text, serial number.
4. The paper font and font size should be unified, refer to the journal template.
5. Increase the number of references.
6. Grammatical errors, read through the full text, and make corresponding changes.
(1) On Pg. 3, line 93. It seems that “each layers” should be deleted the “s”.
(2) On Pg. 3, the before and after tenses must be consistent.
(3) On Pg. 6, line 175. Confirm the subject-predicate agreement.
(4) On Pg. 6, line 202. Please check the “formula”, which is usually a complex number here.
(5) On Pg. 9, line 202. Two-predicate errors.
(6) On Pg. 9, line 202. It seems that “an effects” should be deleted the “s”.
(7) On Pg. 10, line 280. Please check the “growth rate”, article missing.
(8) On Pg. 11, line 312. “horizontal” suspected adjective misused as a noun.
(9) On Pg. 11, line 312. Please confirm that the subject and predicate are consistent.
7. The size of the picture is required to be uniform.
8. The text size contained in the picture is required to be uniform.
9. The image format is not clear.
Author Response
Point 1: The formula and parameter part: the text and the variables and parameters mentioned in the formula give an explanation when they first appear, and the variables are in italics.
Response 1: We have modified it according to the comment.
Point 2: The annotation method of references in this journal adopts sequential coding system, referring to the manuscript template of this journal.
Response 2: We have modified it according to the comment.
Point 3: The figure in the text should appear with the text, serial number.
Response 3: We have modified it according to the comment.
Point 4: The paper font and font size should be unified, refer to the journal template.
Response 4: We have modified it according to the comment.
Point 5: Increase the number of references.
Response 5: We have modified it according to the comment.
[5] Luo, S., Xu, M. Kang, X.B., Li, X.X., Rao, L,F. Analytical solution of external water pressure on deep tunnel lining in horizontally layered hydrogeological structures. Bulletin of Engineering Geology and the Environment, 2022,81(6):
[6] Su, K., Yang, F.J., Nian, F.X., Zhu, H.Z. Anti-seepage and drainage measures of ultra-deep buried tunnel and distribution law of external water pressure of lining. Journal of Central South University(Science and Technology), 2024, 55(06):222-2235.
[7] Ahmad S, Naji M A, Hussain I, Rehman H, Yoo H. Ground Saturation Response During First Filling of Lined Pressure Tunnels: A Case Study. Rock Mech Rock Eng, 2020, (prepublish): 1-23.
[18] Wang, X.R., Liu, X.F., Wang, E.Y., Liu, S.X., Shan, T.C. Microcracking Characterization in Tensile Failure of Hard Coal: An Experimental and Numerical Approach. Rock Mech Rock Eng, 2024, 57(8): 6441-6460.
[19] Hassani N A, Farhadian H, Katibeh H. A comparative study on evaluation of steady-state groundwater inflow into a circular shallow tunnel. Tunn Undergr Sp Tech, 2018, 7315-25.
[24] Lv, Y.X., Jiang, J., Chen, L., Hu, W., Jiang, Y.J. Elaborate simulation and predication of the tunnel drainage effect on karst groundwater field and discharge based on Visual MODFLOW. J Hydrol, 2022, 612(PA):
[25] Park K, Owatsiriwong A, Lee J. Analytical solution for steady-state groundwater inflow into a drained circular tunnel in a semi-infinite aquifer: A revisit. Tunn Under Sp Tech, 2007, 23(2): 206-209.
[26] Zhang, J.W., Zeng, X.T., Tan, Y. Analytical solution for deep pressure tunnels using composite stratum under a groundwater table. Ain Shams Eng J, 2020, 12(2):1419-1434.
Point 6: Grammatical errors, read through the full text, and make corresponding changes.
(1) On Pg. 3, line 93. It seems that “each layers” should be deleted the “s”.
(2) On Pg. 3, the before and after tenses must be consistent.
(3) On Pg. 6, line 175. Confirm the subject-predicate agreement.
(4) On Pg. 6, line 202. Please check the “formula”, which is usually a complex number here.
(5) On Pg. 9. Two-predicate errors.
(6) On Pg. 9. It seems that “an effects” should be deleted the “s”.
(7) On Pg. 10, line 280. Please check the “growth rate”, article missing.
(8) On Pg. 11, line 312. “horizontal” suspected adjective misused as a noun.
(9) On Pg. 11, line 312. Please confirm that the subject and predicate are consistent.
Response 6: Thank you for the suggestion. We have modified it according to the comment.
Point 7: The size of the picture is required to be uniform.
Response 7: We have modified it according to the comment.
Point 8: The text size contained in the picture is required to be uniform.
Response 8: We have modified it according to the comment.
Point 9: The image format is not clear.
Response 9: We have modified it according to the comment.
Author Response File: Author Response.pdf
Reviewer 3 Report
Comments and Suggestions for Authors1. The article title must reflect a novel study in the field. Change it accordingly.
2. Line 12-13; The abstract count analytical and numerical approaches, however the title is only counting the numerical approach.
3. The authors pinpoint the limitations of the analytical approaches, but some basic definitions like homogeneity and isotropic behavior is also associated in the numerical approaches.
4. The abstract reflect that the authors claim the limitation of the analytical approach as the research novelty, however the article air is different. Based on the exiting literature, define the article novelty.
5. As the authors are interested to publish their findings in an international journal, therefore, avoid the words like “foreign scholars”.
6. For the non-hydropower tunnels, the issue which has discussed in the article is the seepage. However, in the hydropower tunnels, such issues are in the opposite scenario. The details are available in the article “Ground saturation response during first filling of lined pressure tunnels: A case study”.
7. Discuss the tunnel construction and support pattern in details. Although the authors have shown the bore hole section. It will be appropriate to show the longitudinal section of the tunnel with experience geology. Also, show the analysis section and the reason behind its selection.
8. Line 115-140; no reference is available.
9. Model input parameters (mechanical, permeability, etc).
10. Support input parameters.
11. Figure 6; the legend is not readable.
12. The authors are dealing with shallow tunnels and in such situations, the topography has a major role in the modelling. Why the authors has not considered the topography?
13. On what basis the authors selected the range for the parametric analysis. Also, the author must discuss the major factors which affect the water pressure.
14. How the authors validated their model?
15. While concluding the study, the conclusion must contain the limitations and application of the findings.
Author Response
Point 1: The article title must reflect a novel study in the field. Change it accordingly.
Response 1: We have modified it according to the comment. The title is “Numerical simulation for the external water pressure in seepage anisotropy under heterogeneous condition” in the revised manuscript.
Point 2: Line 12-13; The abstract count analytical and numerical approaches, however the title is only counting the numerical approach.
Response 2: We have modified it according to the comment. In fact, according to the characteristics of geological conditions, we compared and analyzed the applicability of numerical simulation method and empirical formula method, and finally decided to use numerical simulation method.
Point 3: The authors pinpoint the limitations of the analytical approaches, but some basic definitions like homogeneity and isotropic behavior is also associated in the numerical approaches.
Response 3: We thank the reviewer for the valuable and practical suggestion. Actually, some basic definitions like homogeneity and isotropic behavior is also associated in the numerical approaches. However, considering the limitation of time, We 're sorry we didn't consider this. This manuscript mainly focuses on the influence of anisotropy on external water pressure.
Point 4: The abstract reflect that the authors claim the limitation of the analytical approach as the research novelty, however the article air is different. Based on the exiting literature, define the article novelty.
Response 4: Thank you for the suggestion. We have modified it in the introduction.
Point 5: As the authors are interested to publish their findings in an international journal, therefore, avoid the words like “foreign scholars”.
Response 5: Thank you for the suggestion. We have modified it according to the comment.
Point 6: For the non-hydropower tunnels, the issue which has discussed in the article is the seepage. However, in the hydropower tunnels, such issues are in the opposite scenario. The details are available in the article “Ground saturation response during first filling of lined pressure tunnels: A case study”.
Response 6: We are grateful for the interesting suggestion. We have changed and added the references here(Line38-42).
Point 7: Discuss the tunnel construction and support pattern in details. Although the authors have shown the bore hole section. It will be appropriate to show the longitudinal section of the tunnel with experience geology. Also, show the analysis section and the reason behind its selection.
Response 7: In tunnel engineering, the support of the surrounding rock is a crucial aspect to ensure the safety of tunnel construction and usage. The method used for supporting the surrounding rock in this project is anchor bolt support. Tunnel construction includes initial support, secondary lining, and grouting. Among these, the grouting ring is used to seal off water. The reason for choosing this drilling hole：This section, the terrain is low-lying, the lithofacies are different, and it is easy to form seepage. Affected by groundwater, there may be water inrush and roof fall.
Point 8: Line 115-140; no reference is available.
Response 8: Thank you for the suggestion. We have added the reference.
- Park K, Owatsiriwong A, Lee J. Analytical solution for steady-state groundwater inflow into a drained circular tunnel in a semi-infinite aquifer: A revisit. Tunn Under Sp Tech, 2007, 23(2): 206-209.
- Zhang, J.W., Zeng, X.T., Tan, Y. Analytical solution for deep pressure tunnels using composite stratum under a groundwater table. Ain Shams Eng J, 2020, 12(2):1419-1434.
Point 9: Model input parameters (mechanical, permeability, etc).
Response 9: We have modified it according to the comment(Line 188).
Point 10: Support input parameters.
Response 10: We have modified it according to the comment.
Point 11: Figure 6; the legend is not readable.
Response 11: We have modified it according to the comment.
Point 12: The authors are dealing with shallow tunnels and in such situations, the topography has a major role in the modelling. Why the authors has not considered the topography?
Response 12: Thank you for the suggestion. I’m so sorry about that the project has been completed. Because of the time problem, the topographic map has not been found.
Point 13: On what basis the authors selected the range for the parametric analysis. Also, the author must discuss the major factors which affect the water pressure.
Response 13: According to the results of field physical experiments, we selected the parameter range. And We have added the discuss here(Line38-41 ).
Point 14: How the authors validated their model?
Response 14: We verified according to the field test and empirical formula.
Point 15: While concluding the study, the conclusion must contain the limitations and application of the findings.
Response 15: We have modified it according to the comment.“In addition to the above aspects, our research work still has shortcomings. The current analysis fails to fully consider the important impact of heavy rainfall infiltration on groundwater dynamics. The influence of rainfall infiltration on external water pressure should be considered in the follow-up work.”
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
Comments and Suggestions for AuthorsThe paper is improved and can be published now...
Reviewer 3 Report
Comments and Suggestions for Authors.
