Study on the Deformation Mechanisms of the Surrounding Rock and Its Supporting Technology for Large Section Whole Coal Cavern Groups
Round 1
Reviewer 1 Report
In this paper, the equivalent circle method is used to solve the loose circle of the rectangular road and numerical calculation is used to retain the deformation and stress distribution law of surrounding rock under the excavation condition of large section whole coal cavern groups (WCCG)The deformation and failure mechanism of surrounding rock is revealed under linkage impact between large section whole coal cavern groups. This is a well-written paper containing interesting results which merit publication. For the benefit of the reader, however, several points need clarifying and certain statements require further justification. The following points:
1、Figure 1 is not clear and the figure is not described in detail；
2、Formula 8 is obtained when the pressure measurement coefficient is 1. What is the significance for solving the loose circle problem of rectangular roadway based on the equivalent circle method？
3、What are the boundary conditions of the simulation in Figure 3?
4、How to simulate low and high negative pressure caverns?
5、Figure 5, Figure 9, Figure 11 and Figure 13 are fuzzy, please modify；
6、The numerical simulation does not reflect LBG support technology to improve the stress state of surrounding rock.
7. The deformation mechanism of the surrounding rock and its supporting technology for large section whole coal cavern groups is related with tunnel deformation and failure. Some references related with the mechanism of tunnel deformation and failure should be furtherly reviewed in Introduction. .eg. Experimental Test on Nonuniform Deformation in the Tilted Strata of a Deep Coal Mine/ A Comparative Study on Steady-State Water Inflow into a Circular Underwater Tunnel with an Excavation Damage Zone/ A Unified Solution for Surrounding Rock of Roadway Considering Seepage, Dilatancy, Strain-Softening and Intermediate Principal Stress. / Coupled seepage-damage effect in fractured rock masses: model development and a case study /Mechanical characteristics and deformation control of surrounding rock in weakly cemented siltstone.
Author Response
Please see the attachment.Author Response File: 
Author Response.pdf
Reviewer 2 Report
1.- Lines 57 and 58: Why large section (12~20m2) and large section (≥20 m2), are there some difference?.
2.- The aim will be more specific.
3.-Page 5, Figure 2 bigger
4.- Page 6, line 208, say: r1 into, the correct is: r1 into.
5.- Page 6, line 209, Say: 2.54m, the correct is: 2.54 m
6.- Page 6, line 215, say: 50m and 40 m, the correct is 50 m and 40 m.
7.- Page 7, figure 3: Rearrange, the figure is diffuse.
8.- Page 7, figure 4, Rearrange, the letter it can not be read.
9.- Page 7, figure 5, same comment.
10.- Page 7, line 245, Say: 5.09MPa to 6.71Mpa2, the correct is: 5.09 MPa to 6.71 Mpa.
11.- Page 7, lines 258, 259, and 261, same comment.
12.- Pages 8, and 9: Figures 6, 7, and 8: Rearrange, the letter it can not be read.
13.- Page 14, lines 418-424: Check the text, there are very much words joined, and unify this.
14.- Page 14, lines 427-433: Check the text, there are very much words joined, and unify this.
15.- Page 15, Figure 13: Rearrange, the letter it can not be read.
16.- Pages 15 and, Figures 14 and 15: Rearrange, the letter it can not be read. Enlarge the figures
17.- The conclusión Will be more specific.
18.- There is no discussion, I think it is very important to add this section, to give more relevance to your work.
19.- They do not include the material and methods, results and discussion sections, they must be included
20.- Page 18 line: say stra- ta ¿??
21.-
Check the text, there are very much words joined, and unify this.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Reviewer 3 Report
In this paper, the equivalent circle method is proposed to solve the loose circle of rectangular roadway, and the deformation and stress distribution law of surrounding rock under the condition of excavation of large section full-coal cavern group is obtained through numerical calculation. The research in this paper is relatively in-depth, the content is substantial, and the structure is complete. There are still some problems to be modified.
The following are the questions and some mistakes in this manuscript:
(1) In line 57 of the second page of the article, it is mentioned that what is the difference between the surrounding rock section "lager section (12~20m2)" and "lager section (≥20m2) "?
(2) The figures in the text as a whole are blurred, and the annotated text in the text is not readable, especially the two figures in Fig. 1 and Fig. 13 are not readable at all.
(3) It is suggested that the number of formula (3) should be aligned with other formula numbers. The overall layout of the formula is chaotic. The symbols in the formula are inconsistent with the symbols in the notes. There are also many symbols such as formula (5) σθ and τr that are not annotated. It is suggested to supplement the explanation.
(4) The calculation theory quoted in this paper and the new reinforcement method "LBG" proposed by the author are based on circular section, while the numerical model in this paper uses rectangular section. Can a rectangular section be equivalent to a circular section for numerical calculation? Which is more reasonable for numerical simulation of circular section and rectangular section? It is suggested that the author supplement the explanation.
(5) There is no comparison between the measured stress and deformation data of surrounding rock and the results calculated by the numerical model. Is the numerical model reasonable? Is the subsequent numerical calculation result based on the numerical model meaningful?
To conclude, this paper is well organized, but there are still many of the above problems that need to be revised.
Author Response
Please see the attachment.Author Response File: Author Response.pdf
Round 2
Reviewer 3 Report
All are reviesed based on the comments.
