Research on the Calculation Model and Control Method of Initial Supporting Force for Temporary Support in the Underground Excavation Roadway of Coal Mine

Round 1

Reviewer 1 Report

This article discusses the issues of ensuring the efficiency of underground workings in coal mines.

Coal is the main component of the world fuel and energy balance along with oil and natural gas. At the same time, the main deposits in the world are highly methane-bearing, during the development of which it is possible by means of degassing to extract coal methane suitable for generating electric and thermal energy. However, abundant methane release in coal mines, in accordance with Russian regulations limiting the content of methane in the mine atmosphere, slows down the pace of mining operations and, under certain circumstances, can lead to gassing of workings and create prerequisites for explosions of methane-air mixtures. In order to reduce the likelihood of such prerequisites, it is necessary to apply rational technological schemes for the preparation and development of a suite of methane-bearing coal seams in various mining and geological conditions for the development of coal deposits, effective ventilation schemes for methane-rich coal mines and excavation fields, methods and schemes for degassing the main sources of methane emission with the possibility of subsequent utilization of captured coal mine methane.

Characteristic features of the schemes for opening coal deposits in the fields of specific mines are: opening the fields in a new mine by the main inclined conveyor shaft and vertical auxiliary shafts with a gentle fall; sinking of vertical air supply shafts in existing mines, leaving the existing transport horizon; its simultaneous development by one to three active longwalls with a load of 1 to 5 million tons of coal per year, depending on the thickness of the seam. The preparation of the extraction areas of the mine field for intensive mining of methane-bearing coal seams is carried out taking into account the mining and geological conditions of their occurrence and rational technological solutions that ensure the high-performance operation of modern coal mining equipment while meeting the requirements for safe mining operations in terms of the gas factor.

The choice of a preparation scheme or its individual elements at designed and newly constructed mines is carried out in accordance with the accepted scheme for opening methane-bearing coal seams; design capacity of the mine; number, angles of incidence and methane content of coal seams; depth of mining operations; parameters of the mine field and excavation areas; design productivity of the mine and individual longwalls.

The results obtained in the article are of undoubted interest to readers in the area under consideration, and allow improving the safety of coal mines.

 

However, there are the following issues that should be clarified:

1. In the introduction, it would be necessary to expand the literature review on possible emergencies that occur in coal mines and ways to prevent them in various regions of the world. In particular, the following sources could be considered: 

https://doi.org/10.1016/j.ssci.2023.106170

https://doi.org/10.3390/fire6030095

https://doi.org/10.3390/en16114276

2. Before the section “2.Calculation model for initial support strength and prediction model for supporting 170 strength”, it is desirable to provide a list of the main methods used in the article.

3. To what extent is the division classification according to the zones shown in Figure 5 universal? Is it allowed to change the numerical values of the scale of the considered zones for different conditions?

4. In Figure 7, the term "Hierarchical optimization" is used. However, it is not entirely clear how such optimization is carried out in this case, it should be explained.

5. It should be explained why the Matlab program was used (page 10 of the article). What are its advantages over other software? Along with this, it should be explained how the forecast values were obtained and what the relative errors show (Table 2).

6. The analysis of the algorithm presented in Figure 8 is not fully presented.

7. It should be clarified whether all the initial data are taken into account in the initial control system (Figure 9)?

8. Why was the stability analysis carried out in the article according to the Nyquist criterion? 

There are many other criteria that characterize the stability of the system, why was this criterion used?

9. It should be clarified whether a wider variation of the parameters presented in table 3 is allowed?

10. Enlarge the letters in Figure 12. Why is the word "Figure 12" highlighted in yellow?

11. Is there a patent for the invention for the device shown in Figure 18?

12. Based on the dependencies shown in Figure 19, it would be possible to carry out a regression analysis with specific mathematical models and determination coefficients.

13. In the conclusions, one should dwell in more detail on the approbation of the results obtained at specific production facilities.

Author Response

Please see the file attached

Author Response File: Author Response.pdf

Reviewer 2 Report

This paper proposes a temporary support system for improving the efficiency and safety of underground roadway excavation in coal mines. To achieve efficient and adaptive control of the initial supporting force of temporary supports at different locations, the study designs a support force controller based on simulated annealing particle swarm optimization (SAPSO-PID). The simulation results demonstrate that the proposed support force control system efficiently achieves adaptive control of the initial supporting force of temporary supports. This work is well-written and organised. I recommend the publication after minor revision. Please see the following comments

1. PID should be defined in the abstract.

2. In Figure 9, it should be input information.

3. In Figures 15 and 16, numerical oscillations can be observed. What causes these oscillations?

 

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 3 Report

This paper introduces a comprehensive approach involving calculation models, prediction techniques, and a simulation-based support force controller to enhance the efficiency and safety of underground roadway excavation in coal mines by achieving adaptive control of initial supporting forces in the temporary support system.

The design of a support force controller based on simulated annealing particle swarm optimization (SAPSO-PID) is intriguing, although my expertise as a tunnel engineer is not deeply rooted in mechanical control systems.

 

Some minor issues:

1.    Line 110: What is the “OSF method”. Please explain the acronym.

2.    Line 113: What is the “PID”. Please explain the acronym.

3.    Line 150: Provide reference for AMESim.

4.    Line 151: Provide reference for Matlab.

5.         Section 2.1: The explanation of the calculation model is unclear. Please use the symbols provided in Fig. 4 also in the text. What do you mean by “direct top of the roadway”? what is the “rated working resistance”?

6.         Fig. 4: The figure is unclear. Is this a longitudinal section? Please add some labels.

7.         Eq. 1: Some of the symbols are not shown in Fig. 4. Please add them.

8.         Line 229: P0=800 kN. Please add spaces before “=” as in P0 = 800 kN. This issue occurs several times in the manuscript. Please amend.

9.         Table 1: This is definitely not a “database”. Please amend the caption as “Hydraulic cylinder chamber pressure as a function of the bracing force”.

10.      Line 521: “Figure 12” is highlighted in yellow. Please amend.

11.      Fig. 12b: Please delete the redundant spaces in the axis units “(second              -1)”.

12.      Fig 12: Please keep the caption on the same page of the figure.

13.      Line 530: “point (-1, j0)”. What is “j0”?

14.      Line 607: “The intelligent emulsion pumping station”. Please explain what this emulsion pumping station is and why it is intelligent.

15.      Line 611: What is the “CANBUS bus”. Please explain.

16.      Line 617: “BR Automation Studio software”. Please add reference.

17.      Line 668: “findings presented in this paper hold immense significance”. This sounds like a huge claim. Please mitigate the hubris.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Round 2

Reviewer 1 Report

The authors finalized the articles and took into account my comments. Thanks to the authors for their work. The article may be published.

Author Response

Thank you for recommending the publication of my work. Additionally, I extend my gratitude for thoroughly reviewing my manuscript and offering valuable insights. I wish you continued happiness, excellent health, and continued success in your career.

Reviewer 2 Report

The authors have addressed all reviewers' comments. I recommend the publication of this work.

Author Response

Thank you for recommending the publication of my work. Additionally, I extend my gratitude for thoroughly reviewing my manuscript and offering valuable insights. I wish you continued happiness, excellent health, and continued success in your career.

Reviewer 3 Report

This paper introduces a comprehensive approach involving calculation models, prediction techniques, and a simulation-based support force controller to enhance the efficiency and safety of underground roadway excavation in coal mines by achieving adaptive control of initial supporting forces in the temporary support system.

The design of a support force controller based on simulated annealing particle swarm optimization (SAPSO-PID) is intriguing, although my expertise as a tunnel engineer is not deeply rooted in mechanical control systems.

 

Some minor issues:

1.    Line 150: Provide reference for AMESim.

The authors explained what AMESim is, which is OK. However, the reviewer meant a citation link to the software. Please cite the reference guide/manual.

2.    Line 151: Provide reference for Matlab.

Same as above. Please cite the reference guide/manual.

3.         Line 607: “The intelligent emulsion pumping station”. Please explain what this emulsion pumping station is and why it is intelligent.

The authors explained, in their response, what the emulsion pumping station is. However, this must also be included in the text.

4.         Line 617: “BR Automation Studio software”. Please add reference.

The authors explained, in their response, what BR Automation Studio software is, which is OK. However, the reviewer meant a citation link to the software. Please cite the reference guide/manual. Also, add the explanation to the manuscript.

Author Response

Point-by-Point Responses to Reviewer #3 Comments

Dear Reviewer,

Thank you for your second round of feedback on our manuscript. We appreciate your thorough review and have made changes accordingly. Here are our responses to your minor issues:

（In contrast to the revisions from the first round, we have distinguished the revisions made in the second round by using red font for emphasis.）

Comment # 1*

Provide reference for AMESim.( The authors explained what AMESim is, which is OK. However, the reviewer meant a citation link to the software. Please cite the reference guide/manual.)

Authors’ response:

Thank you for your suggestion. We apologize for the oversight. Following your suggestion, we have incorporated pertinent references into line 156 of the manuscript.

Comment # 2* Provide reference for Matlab. ( Same as above. Please cite the reference guide/manual.)

Authors’ response:

In a similar vein, we have included pertinent references at line 156 of the manuscript.

Comment # 3* Line 607: “The intelligent emulsion pumping station”. Please explain what this emulsion pumping station is and why it is intelligent. ( The authors explained, in their response, what the emulsion pumping station is. However, this must also be included in the text.)

Authors’ response:

Thank you for your suggestion. We have incorporated pertinent explanations into line 627 of the manuscript, following your suggestion.

Comment # 4* Line 617: “BR Automation Studio software”. Please add reference. ( The authors explained, in their response, what BR Automation Studio software is, which is OK. However, the reviewer meant a citation link to the software. Please cite the reference guide/manual. Also, add the explanation to the manuscript.)

Authors’ response:

Thank you for your suggestion. We have incorporated pertinent references into line 646 of the manuscript.

 

 

Once again, we appreciate your valuable input, and we are committed to addressing all the concerns raised in your review. If you have any further suggestions or questions, please do not hesitate to let us know.

 

 

Thank you for your time and consideration.

 

Best regards, Rui Li.

Round 3

Reviewer 3 Report

This paper introduces a comprehensive approach involving calculation models, prediction techniques, and a simulation-based support force controller to enhance the efficiency and safety of underground roadway excavation in coal mines by achieving adaptive control of initial supporting forces in the temporary support system.

The design of a support force controller based on simulated annealing particle swarm optimization (SAPSO-PID) is intriguing, although my expertise as a tunnel engineer is not deeply rooted in mechanical control systems.

 

Some minor issues:

All issues have been resolved.