Study on the Influence of Soil Engineering Geological Characteristics at Key Tectonic Sites on High-Speed Railway Foundation—A Case of the Beijing–Zhangjiakou High-Speed Railway (Huailai Section)
Round 1
Reviewer 1 Report
Dear Editor
The authors conduct a study to examine the differential settlement of a high-speed railway in China. They also study engineering geological characteristics affecting the settlement and deformation of the pile foundation of the high-speed railway and concluded some remarks.
This paper describes a case study and there are some issues that the authors should consider in the revision round.
Please consider the following comments.
General Comments:
Since the paper describes a case study. It should be highlighted in the Title.
The Abstract should be shortened and conclusion remarks should be added.
Keywords contain mostly 3-4 words. They should be revised.
What is the novelty of the paper? It should be highlighted in the Introduction section. An in-situ experiments? New measurement techniques? Performed regular techniques? What is the soundness in this manuscript?
Earthquake history of the study area/region and the hazards recorded should be also mentioned in the text. Figure 1 may not be sufficient to understand this issue.
What is g watt in line 207?
Geotechnical classification given in Table 2 must be referenced and included in references.
The abbreviation of logarithm is log. Please consider it and correct where necessary.
The authors explained the differences of Fig. 4 in lines 227-231. What about water content varying in depth? Did they measure? If yes, the results should be included.
From Table 4, Cs/Cc varied between 0.0036 and 0.0516. The authors mentioned it as 0.01-0.04 in the related section, Abstract and Conclusion.
Is it logical to fit Cc with Cc/e0 in Figure 6 by finding a linear variation? How would Eq. 5 change by eliminating the intercept value (y=ax)? Eliminating the intercept value would contribute to find the optimal value of e0.
Which version of ANSYS was used?
In modelling studies, inputs, boundary conditions, mesh sizes/types, number of elements, governing equations, discretization schemes, simulation time, etc. must be clearly defined in the relevant sections.
What about errors?
What about numerical diffusion?
How did the authors validate their models?
What about sensitivity of parameters on the results? Which parameter dominate the results?
What are the advantages of the methodology?
Discussion section must be enlarged by discussing the findings and compatibility with literature.
Conclusion section must be enlarged and avoided summarization.
Author Response
Dear Reviewer
Thanks a lot for reviewing our manuscript. We have substantially revised our manuscript after reading the comments provided by you. We again thank you for considering our work and look forward to your response at your earliest convenience.
Below is our response to the reviewers' comments and the explanation of the details of the revisions to the manuscript.
Point 1: Since the paper describes a case study. It should be highlighted in the Title. The Abstract should be shortened and conclusion remarks should be added. Keywords contain mostly 3-4 words. They should be revised.
Response 1: Thanks for your suggestion, the author has changed the title to "Study on the influence of engineering geological characteristics of soils at key tectonic sites on high-speed railway Foundation -- A Case of Beijing-Zhangjiakou high-speed railway (Huailai section)". And cut the keywords down to four.
Point 2: What is the novelty of the paper? It should be highlighted in the Introduction section. An in-situ experiments? New measurement techniques? Performed regular techniques? What is the soundness in this manuscript?
Response 2: The feature of this paper is that the stratigraphic structure 500m deep of a major project such as the Beijing-Zhangjiakou high-speed railway has not been disclosed to the public. Previous study on the deformation of high-speed railway foundation are limited to the long-term creep of static load or cyclic loading of dynamic load, and the deformation of high-speed railway foundation across hidden active faults under different dynamic loads has not been considered. This paper analyzes these problems one by one.
Point 3: Earthquake history of the study area/region and the hazards recorded should be also mentioned in the text. Figure 1 may not be sufficient to understand this issue.
Response 3: Thanks for your suggestion. The author has added the historical earthquake disaster records of Zhangjiakou in section 2.1.
Point 4: What is g watt in line 207 ?
Response 4: “76 g watt conical instrument” means the conical instrument used is Vasilev conical instrument (cone mass 76g, cone Angle 30°).
Point 5: Geotechnical classification given in Table 2 must be referenced and included in references.
Response 5: The author has added it as a reference.
Point 6: The abbreviation of logarithm is log. Please consider it and correct where necessary.
Response 6: The author has modified formula 1 and 2.
Point 7: The authors explained the differences of Fig. 4 in lines 227-231. What about water content varying in depth? Did they measure? If yes, the results should be included.
Response 7: The relationship between water content and depth is expounded in this paper. Due to the existence of groundwater level and other factors, the water content of various soils has little relationship with buried depth.
Point 8: From Table 4, Cs/Cc varied between 0.0036 and 0.0516. The authors mentioned it as 0.01-0.04 in the related section, Abstract and Conclusion.
Response 8: According to the experimental results, the Cs/Cc values of the soil samples measured in Table 4 are only one 0.0036 and one 0.0516. The paper describes the main range of Cs/Cc, so the minimum and maximum values with low outgoing frequency are discarded
Point 9: Is it logical to fit Cc with Cc/e0 in Figure 6 by finding a linear variation? How would Eq. 5 change by eliminating the intercept value (y=ax)? Eliminating the intercept value would contribute to find the optimal value of e0.
Response 9: Previous experimental studies(Park et al. (2004)) have found that the formula between Cc /e0 and Cc is highly linear, and has nothing to do with soil layer sensitivity. This paper, the same fitting is carried out to Figure 6, which not only reveals the relationship between Cc and e0, but also applies this formula to a wider range (regardless of soil layer sensitivity, soil properties, and buried depth). This formula can not eliminate the intercept, if you eliminate the intercept, it becomes a relationship between e0 and 1. It is not scientific or rational to do so.
Point 10: Which version of ANSYS was used?
Response 10: We purchased the copyright of version of ANSYS 10.0. Although ANSYS is updated and expanded with new functions every year, its solver remains unchanged and has no impact on the calculation.
Point 11: In modelling studies, inputs, boundary conditions, mesh sizes pes, number of elements, governing equations, discretization schemes, simulation time, etc. must be clearly defined in the relevant sections.
Response 11: Thanks for your suggestion and it has been revised in section 4.2. The normal displacement constraints are applied to the front, back, left and right sides of the model, respectively. The vertical displacement constraints are applied to the bottom boundary of the model, and the top of the model is a free surface without any constraints. The mesh size is 10 m. The number of elements is 24197. The number of nodes is 5276.
Point 12: What about errors?
Response 12: During the meshing stage, a coarse grid division was first made, and then the fine grid division was made. In the calculations, it was found that they were convergent at one point. So the error was considered negligible.
Point 13: What about numerical diffusion?
Response 13: The paper uses the SOLID185 element to mesh the model. The element is defined by 8 nodes, and each node has 3 degrees of freedom that translate along the x, y, and z directions. Grid the 3D geological model through finite element modelling technique. As the model is far away from Guanting reservoir, groundwater seepage is not considered in this paper.
Point 14: How did the authors validate their models?
Response 14: Model validation is discussed in discussion section 5.2. The results of numerical simulation show that the dynamic stress of the surface soil along the high-speed railway line is 0.5~1.2kPa (Figure 11), which is basically consistent with the measured value (about 1~1.5kPa) in other published papers. It can be considered that the loading mode of dynamic load in numerical simulation is reasonable. The measured value along the Beijing-Zhangjiakou high-speed railway line needs further studied after INSAR data decryption and interpretation to further verify the result of the model.
Point 15: What about sensitivity of parameters on the results? Which parameter dominate the results?
Response 15: The physical and mechanical properties of soil and the train load affect the modeling results. The selection of elastic modulus, Poisson ratio and other physical and mechanical parameters are based on laboratory tests and empirical values. The train load impact the modeling results significantly. The vertical displacement decreases with the increase of train speed.
Point 16: What are the advantages of the methodology?
Response 16: Ansys is simple and convenient to operate, and has become the most popular finite element analysis software in the world. It has been widely used in geotechnical engineering. This paper used Ansys to analyze the settlement of soil along the Beijing-Zhangjiakou high-speed railway line.
Point 17: Discussion section must be enlarged by discussing the findings and compatibility with literature.
Response 17: Thanks for your suggestion. In the discussion part, the author mainly analyzes the selection of model parameters in the modeling to prove that our work is scientific, reasonable and practical on the basis of previous studies.
Point 18: Conclusion section must be enlarged and avoided summarization.
Response 18: Thanks for your suggestion. The author has re-edited and modified the conclusion.
Author Response File: 
Author Response.docx
Reviewer 2 Report
Line 131, what etc, stand for; please elaborate.
Table 1, equivalent dose and age, should be referred to three significantt figures.
Figure 3 needs to be in higher resolution.
Table 3, not all numbers are in 3 significant figures format.
For figures 5 and 6 it would be nice to have also the linear regression values in the text.
Table 4, not all numbers are in 3 significant figures format.
Line 461, InSAR data is briefly mentioned but not substantiated.
Overall, the scientific work is sound. The manuscript will benefit more by going further to provide meaningful information from the data analysis. This is rather limited. The laboratory methods for getting the data are not provided.
Author Response
Response to Reviewer 2 Comments
Dear Reviewer
Thanks a lot for reviewing our manuscript. We have substantially revised our manuscript after reading the comments provided by you. We again thank you for considering our work and look forward to your response at your earliest convenience.
Below is our response to the reviewers' comments and the explanation of the details of the revisions to the manuscript.
Point 1: Line 131, what etc, stand for; please elaborate.
Response 1: The authors have added Tianzhen-Yanggao Basin, Yangyuan Basin, Yuxian Basin, deleted the “etc”.
Point 2: Table 1, equivalent dose and age, should be referred to three significantt figures.
Response 2: The authors have modified the significant numbers in the Table 1.
Point 3: Figure 3 needs to be in higher resolution.
Response 3: The authors have improved the resolution of Figure 3.
Point 4: Table 3, not all numbers are in 3 significant figures format.
Response 4: The authors have completed all numbers which are in 3 significant figures format.
Point 5: For figures 5 and 6 it would be nice to have also the linear regression values in the text.
Response 5: The authors have added linear slope values between related parameters in the paper.
Point 6: Table 4, not all numbers are in 3 significant figures format.
Response 6: The authors have completed all numbers which are in 3 significant figures format.
Point 7: Line 461, InSAR data is briefly mentioned but not substantiated.
Response 7: Because InSAR data is classified and unclassified interpretation has not been completed at present, no comparative data analysis has been provided. After the interpretation is completed, the author will conduct detailed comparative analysis.
Author Response File: Author Response.docx
Round 2
Reviewer 1 Report
The authors should make sure whether they revised the title of the manuscript when submitting. Although it was revised in the manuscript, it was not changed when you looked at article information.
Authors did not refer the changes in the revised manuscript. It is not easy to catch the revisions author has made.
The reviewer asked the novelty of the paper (What is the novelty of the paper? It should be highlighted in the Introduction section. An in-situ experiments? New measurement techniques? Performed regular techniques? What is the soundness in this manuscript?). However, the authors preferred replying outside of the manuscript. Reviewer requested highlighting in the manuscript.
Reviewer remarks the same points since they were not clarified.
What is g watt in line 206?
Authors expressed that they included the reference of geotechnical classification. Reviewer cannot catch this reference in reference list. It should be clearly written in cover letter.
From Table 4, Cs/Cc varied between 0.0036 and 0.0516. The authors mentioned it as 0.01-0.04 in the related section, Abstract and Conclusion. Authors interpret the Cs/Cc values from Table 4. In cover letter, authors express that they interpreted the main range of Cs/Cc. It is not acceptable, authors should revise these statements and may discuss this issue.
In Equation 6, why the intercept value cannot be eliminated? When w=0, what is e0? Does this equation satisfy this value?
Reviewer requested inclusion of the version of ANSYS. It should be written. Any problem if the author includes the version? Reviewer did not ask the output sensitivity regarding ANSYS version.
In modelling studies, inputs, boundary conditions, mesh sizes/types, number of elements, governing equations, discretization schemes, simulation time, etc. must be clearly defined in the relevant sections.
When the reviewer asked the errors why did the authors prefer discussing outside of the manuscript. It should be included in the manuscript.
Reviewer re-asks the following points and would like to see discussion in the manuscript.
1. What about sensitivity of parameters on the results? Which parameter dominate the results?
2. What are the advantages of the methodology?
3. Discussion section must be enlarged by discussing the findings and compatibility with literature.
4. Conclusion section must be enlarged and avoided summarization.
Author Response
Point 1: The authors should make sure whether they revised the title of the manuscript when submitting. Although it was revised in the manuscript, it was not changed when you looked at article information.
Response 1: The authors does not have the right to modify the title information of the web page, we have contacted the editor to change the article information.
Point 2: Authors did not refer the changes in the revised manuscript. It is not easy to catch the revisions author has made.
Response 2: The author has submitted a manuscript showing the modification pattern. The editor says he didn't send you the revised version showing the changes. This time, we put the modified part in red font, so that you can catch the modified part.
Point 3: The reviewer asked the novelty of the paper (What is the novelty of the paper? It should be highlighted in the Introduction section. An in-situ experiments? New measurement techniques? Performed regular techniques? What is the soundness in this manuscript?). However, the authors preferred replying outside of the manuscript. Reviewer requested highlighting in the manuscript.
Response 3: The author has added relevant content to the new manuscript in the introduction.
Point 4: What is g watt in line 206?
Response 4: Here is not “g watt”. “76 g watt conical instrument” means “76g , watt conical instrument “. International conical instrument for measuring liquid limit is watt conical instrument. Watt's body weight is 76 grams.
Point 5: Authors expressed that they included the reference of geotechnical classification. Reviewer cannot catch this reference in reference list. It should be clearly written in cover letter.
Response 5: The author has added it as reference [32].
Point 6: From Table 4, Cs/Cc varied between 0.0036 and 0.0516. The authors mentioned it as 0.01-0.04 in the related section, Abstract and Conclusion. Authors interpret the Cs/Cc values from Table 4. In cover letter, authors express that they interpreted the main range of Cs/Cc. It is not acceptable, authors should revise these statements and may discuss this issue.
Response 6: The authors have modified the ratio of Cs/Cc to 0.0036-0.0516.
Point 7: In Equation 6, why the intercept value cannot be eliminated? When w=0, what is e0? Does this equation satisfy this value?
Response 7: Thanks for your suggestion. For the intercept problem of formula 5, the author will explain this as follows: First of all, this is a soil mechanics problem, not a mathematical problem. Soil is a very complex material, not a perfect tiny particle, which is why the intercept in the empirical formula has important significance. Secondly, the limiting state of soil mass, such as w = 0 and Cc = 0, does not exist in practical engineering. They only occur in laboratory human intervention. The empirical formula in this paper is based on the real data measured in the laboratory for normal soil mass. At the same time, appropriate mathematical means are adopted to sum up the empirical formula, so as to guide practical engineering and accept the test of measured data. Finally, the author has also carried out linear or exponential matching of the Cc and e0, but the matching curve is very chaotic. Therefore, we referred to the research of Park et al., and expanded on the basis of their research.
Point 8: Reviewer requested inclusion of the version of ANSYS. It should be written.
Response 8: The author has added the version into the article.
Point 9: In modelling studies, inputs, boundary conditions, mesh sizes/types, number of elements, governing equations, discretization schemes, simulation time, etc. must be clearly defined in the relevant sections.
Response 9: Thanks for your suggestion and it has been revised in section 4.2.
Point 10: When the reviewer asked the errors why did the authors prefer discussing outside of the manuscript. It should be included in the manuscript.
Response 10: The author has added this part in section 4.2.
Point 11: Reviewer re-asks the following points and would like to see discussion in the manuscript.
Response 11: Thanks for your suggestion and it has been revised in relevant section
Author Response File: Author Response.docx
Round 3
Reviewer 1 Report
Title of the manuscript is now compatible with the submission system.
The authors point out the remarks raised by the reviewer in cover-letter. However, the authors should discuss those issues in the manuscript. For example, at intercept of Eq 6, reviewer find replies convincing, but they are not highlighted in the manuscript.
In previous cover letter, the authors reply that they purchase ANSYS 10.0. However, they included the version as 14.5.
Some of the concerns were not considered. For instance, reviewer asks the parameter sensitivity on the results, etc. Nevertheless, reviewer found the manuscript acceptable.
