Factors Influencing Post-Construction Responses of Underlying Tunnel below Excavation Base in Gravelly Clay
Round 1
Reviewer 1 Report
The paper in general is well written and presents information that is of great interest to the geotechnical engineering community from a practical and research perspectives. From my viewpoint, the results might have research significance as long as the comments described in this document are carefully addressed by the authors. The following comments and changes need to be incorporated in a revised manuscript to improve the clarity and quality of the paper. The comments are not presented in order of priority:
R1: Provide more insight into the measurements shown in Table 2. How was that measured?
R2: Line 73 has a typo. Please revise.
R3: There is a typo in Table 2 (row 2).
R4: The discussion from Lines 358 to 367 is hard to follow and the reviewer strongly recommends revising very carefully what is written there.
R5: Please further refine each conclusion.
Author Response
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Reviewer 2 Report
This paper investigates the post-construction tunnel responses to overlying excavation and influencing factors. The research is of significance to engineering practice because the post-construction tunnel responses are generally appreciable and relevant research is sparse. On the whole, this paper should become acceptable pending minor revisions in light of the appended comments:
1. Superstructure construction in engineering practice generally leads to the surcharge on the excavation base and also prevent the seepage. The authors need to introduce the magnitude of surcharge due to superstructure construction.
2. The reason behind the no effects of soil permeability on the normalized tunnel heave illustrated in Fig. 16 should be further explained.
3. “Fitting degree” for R2 should be replaced by “coefficient of determination”.
4. Use of articles should be checked throughout the manuscript.
5. Period adopted among Line 170 to Line 172 should be replaced by comma.
Using full title or symbol for the vertical and horizontal coordinates should be unified throughout the manuscript.
Author Response
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Reviewer 3 Report
The article describes factors influencing post-construction responses of underlying tunnel below excavation base in gravelly clay. However, due to the poorly accepted input data for the FEM model, the calculation results are incorrect, which disqualifies any further findings. In addition, there are a number of inaccuracies in the article that need to be corrected.
The article is not suitable for publication in Sustainability as it stands.
General remarks
1. A separate subchapter should clearly define the purpose and scope of the research.
2. Subsection "3.1. Engineering Background" should be found in Chapter 2.
3. In Chapter 1, the works of other authors are cited in a very general manner, without giving details.
4. Terminology should be standardized: eg stiffness or rigidity.
5. In Tab. 1 incorrectly accepted input parameters of the structure. Consequently, further calculations are inappropriate. Why is the modulus of elasticity reduced since it is a material property? Moreover, what reduction in the modulus of elasticity is envisaged for steel since Ered = 210 GPa? .
6. Lack of information on how the soil permeability was determined.
The article is not well written and needs improvement.
Specific remarks
7. 25 line: Please explain the symbol Ly.
8. 53 line: Please explain why.
9. 95 line: Please explain in the article on what basis the reduction of stiffness was adopted.
10. 97 line: How do the authors justify the determination of the effective degree of effectiveness of stiffness?
11. 99 line, Tab.1: What is the Poisson's ratio for steel? On what basis was the modulus of elasticity assumed for steel and concrete? How was the reduction of the steel elastic modulus Ered = 210 GPa assumed?
12. 114 line: Please explain what characterizes the size "m".
13. 116 line: Module but what? Should be given.
14. 121 line: How deep was the trench basically? 4 x 120 mm?
15. 170 line; Describe the symbols in Eq.1 clearly.
16. 181 line Fig.4: What is the size on the ordinate? You should write what the abbreviation "Cal." Means. Is the formula in Fig. 4 complete?
17. 192 line Fig.5: In the ordinate axis, the symbol "d" should be explained.
18. 192 line Fig.6: On the abscissa the symbol "d" should be explained.
19. 214 line Fig.7: What is the size on the ordinate which stands for Cal.? Are the formulas in the drawing complete?
20. 217 line: In which units is the T shown?
21. 181 line Fig.4: What is the size on the ordinate and what does the abbreviation "Cal." ?
22. 304 line: Should read: "permeability rate" or "a coefficient of permeability k".
23. 305 line: Please state how the permeability k was determined.
24. 323 line Fig.16: In the ordinate what is the size? Is the graph equation complete?
25. 368 line Fig.19: What is the size on the ordinate? Are the equations in the graph complete?
I recommend an in-depth review of the manuscript, including comments, to make it an article suitable for publication in the Sustainability.
Author Response
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Author Response File: Author Response.pdf
Round 2
Reviewer 3 Report
Compared to the previous version of the article, they have introduced corrections that partially reflect the reviewer's suggestions. However, there are still serious inaccuracies which need to be corrected.
1. The authors of the article still did not provide basic information on the items in question in the literature review in chapter 1. This is very important due to the possibility of comparing the findings of previous research with the information provided in the current article. Otherwise, such a general literature review has nothing to do with the subject of the article.
2. Again, I ask the following questions: Why do the authors reduce the modulus of elasticity of steel, since it is a material property. In other words: If we reduce the strain and stress (the stress-strain relationship), then the value of the steel elasticity modulus should not change. Since the modulus of elasticity is by definition the ratio of stress to strain (Hooke's law). The modulus of elasticity for a commonly used structural steel is between 205 and 210 GPa. Hence the question why then the unreduced value of the elastic modulus is 262.5 GPa? Why is the Poisson's ratio for steel 0.2? Please check. The Poisson's ratio for steel is on average 0.3.
3. Ad. 13 It is not clear why the authors do not understand the question. G is by definition "shear modulus". Therefore, it should be correctly defined.
4. Ad. 19 The answer to the second question is No. Because the equation is invisible at the beginning (the symbol Δ is missing). The same applies to Notes 16, 24, 25.
5. Ad.20 First, the unit used in the article is "days", not "day". So the unit "days" and not "day" should be entered.
The article requires a thorough correction of the calculations.
Author Response
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