Research on the Mechanism of Coal-Wall Spalling and Flexible Reinforcement in Soft-Coal Seams Based on the Mogi–Coulomb Criterion
Round 1
Reviewer 1 Report
Comments and Suggestions for AuthorsIn this paper, based on the condition of 91-105 working face in Lu'an Wangzhuang Mine, the authors derived the safety stability coefficient of coal wall under the limit equilibrium condition by applying the Mogi-Coulomb criterion. It was found that the most dangerous sliding surface of the coal wall is at 0.6 times of the mining height. And then, the control mechanism of the grouting and flexible rope reinforcing technology for the coal wall spalling in the soft coal seam is revealed. This manuscript is interesting to read, and the findings of this research provide valuable insights for the sustainability and safety of mining. However, the following suggestions are offered for the author's consideration:
(1) Regarding the status of previous studies, the manuscript has listed some related research, lacking systematic summary and organization. Please review and update with the most recent references.
(2) The overall concept of this manuscript is distinct and the structure is compact. Nevertheless, the investigation and introduction of the engineering case is somewhat weak.
(3) Several figures presented in the paper lack sufficient clarity, and the expression is ambiguous, as indicated in Figure 1, Figure 5, Figure 15, and so on.
(4) The conclusions of the paper appear somewhat weak, lacking organization and a logical flow. It is recommended to revise and strengthen the summary to enhance clarity and cohesion.
Author Response
Comment 1: Regarding the status of previous studies, the manuscript has listed some related research, lacking systematic summary and organization. Please review and update with the most recent references.
Response: Thank you very much for this suggestion. We've restructured the introduction and added a summary (line 42-64, 73-75, and 84-88 in the introduction) with the most recent references (the reference 2, 3, 6, 15, 23, 24, 26, 30, and 31) in the revised manuscript.
Comment 2: The overall concept of this manuscript is distinct and the structure is compact. Nevertheless, the investigation and introduction of the engineering case is somewhat weak.
Response: Thank you very much for this suggestion. We have added the investigation and introduction (line 100-103, 106-107, 112, and 126 in the section 2.1 of the revised manuscript) of the engineering case in the revised manuscript.
Comment 3: Several figures presented in the paper lack sufficient clarity, and the expression is ambiguous, as indicated in Figure 1, Figure 5, Figure 15, and so on.
Response: Thank you very much for this suggestion. We have increased the clarity of figures and modified the ambiguous expression in the revised manuscript.
Comment 4: The conclusions of the paper appear somewhat weak, lacking organization and a logical flow. It is recommended to revise and strengthen the summary to enhance clarity and cohesion.
Response: Thank you very much for this suggestion. We have reorganized and added the summary (line 444-468 in the conclusions of the revised manuscript) in the conclusion of the revised manuscript.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
Comments and Suggestions for AuthorsThe main focus of this study is to investigate the mechanism of coal wall spalling in soft coal seam working faces and the effectiveness of flexible reinforcement technology. Through theoretical analysis and modeling, the literature aims to improve the safety and sustainability of coal mining. Meanwhile, the article considers the coal wall spalling mechanism of horizontal ground stress difference, which is innovative. The overall structure of the paper is complete, the research approach is innovative, the writing and logical flow are good, and the research results have significant application value. The specific review comments are as follows:
1. The introduction can elaborate on the theoretical basis and applicability of the Mogi-Coulomb criterion, and why it was chosen for research.
2. Are there any limitations or deficiencies in the 3D model of the spalling shape of the coal wall and the mechanical model established? The recommendations complement the discussion and provide recommendations for future research improvements and optimizations.
3. In the discussion section, the headings of section 4.1 are duplicated with section 4.2.
4. The results section could be added to include data analysis and explanations of related phenomena, rather than just a statement of the data.
5. These articles may be helpful in improving the quality of the manuscript, please check them out:
https://doi.org/10.1016/j.oceaneng.2024.118320
https://doi.org/10.1016/j.geotexmem.2024.06.002
Author Response
Comment 1: The introduction can elaborate on the theoretical basis and applicability of the Mogi-Coulomb criterion, and why it was chosen for research.
Response: Thank you very much for this suggestion. We have added to the introduction the elaboration of the Mogi-coulomb criterion and the reasons for its selection in the revised manuscript (line 53-64 in the introduction of the revised manuscript).
Comment 2: Are there any limitations or deficiencies in the 3D model of the spalling shape of the coal wall and the mechanical model established? The recommendations complement the discussion and provide recommendations for future research improvements and optimizations.
Response: Thank you very much for this suggestion. This model is not suitable for coal seams that contain faults and other modes such as tensile failure. We have added a detailed discussion of model limitations and future research directions to the paper (line 413-429 in the section 4.5 of the revised manuscript). In the future, we will continue to improve the model and expand the applicability of the model.
Comment 3: In the discussion section, the headings of section 4.1 are duplicated with section 4.2.
Response: Thank you very much for this suggestion. We have removed the duplicate headings of section 4.2 in the revised manuscript.
Comment 4: The results section could be added to include data analysis and explanations of related phenomena, rather than just a statement of the data.
Response: Thank you very much for this suggestion. We have added the data analysis and explanations (line 274- 278, 294-297, 314-316, 321-325, 333-334 and 351-353 in the section 4.1 of the revised manuscript) of related phenomena in the revised manuscript.
Comment 5: These articles may be helpful in improving the quality of the manuscript, please check them out: https://doi.org/10.1016/j.oceaneng.2024.118320
https://doi.org/10.1016/j.geotexmem.2024.06.002
Response: Thank you very much for these articles. We have consulted these references and added citations (the reference 2
Author Response File: Author Response.pdf
Reviewer 3 Report
Comments and Suggestions for Authors- Simplify the narrative structure and streamline technical explanations to improve accessibility for a multidisciplinary audience.
- Highlight the unique contributions compared to prior work.
- Enhance the presentation of figures and tables for better interpretability.
- Include a section addressing the limitations of the proposed methods and potential directions for future research.
Author Response
Comment 1: Simplify the narrative structure and streamline technical explanations to improve accessibility for a multidisciplinary audience.
Response: Thank you very much for these articles. We have simplified narrative structure and streamline technical explanations in the revised manuscript.
Comment 2: Highlight the unique contributions compared to prior work.
Response: Thank you very much for this suggestion. We've revised the structure of the introduction to include the differences from previous research work (line 58-59 and 84-86 in the introduction of the revised manuscript) in the revised manuscript.
Comment 3: Enhance the presentation of figures and tables for better interpretability.
Response: Thank you very much for this suggestion. We have revised the obscure figures, tables and the corresponding representation in the revised manuscript.
Comment 4: Include a section addressing the limitations of the proposed methods and potential directions for future research.
Response: Thank you very much for this suggestion. We have added a section on method limitations and potential directions for future research (line 413-429 in the section 4.5) in the discussion of the revised manuscript.
Author Response File: Author Response.pdf
Reviewer 4 Report
Comments and Suggestions for AuthorsThis paper addresses a significant issue in underground mining: coal wall spalling in soft coal seams. Its focus on the Mogi-Coulomb criterion and reinforcement strategies is highly relevant to the ongoing need for improved mining safety and sustainability. The integration of theoretical modelling, limit equilibrium analysis, and reinforcement techniques is well thought out, offering a solid foundation for the findings. The mathematical modelling provides valuable insights, while the use of real-world data from the Lu’an Wangzhuang Coal Mine adds practical relevance, helping readers assess the applicability of the proposed solutions.
However, there are a few areas for improvement:
- Some sentences are long and complex, making them difficult to follow. Simplifying technical jargon where possible could improve clarity.
- The abstract could more clearly summarize the key findings and their implications, making the study’s contributions more accessible to a wider audience.
- The inclusion of specific values or percentages related to the findings would strengthen the results and provide more concrete evidence.
- The introduction reviews prior research but lacks a clear problem statement outlining the research gap this study addresses. A more explicit identification of the gap would help clarify the paper's significance.
- Some of the cited literature is relatively outdated. Incorporating more recent studies would enhance the paper’s credibility and demonstrate a more comprehensive review of the current state of research.
- The assumptions made in the mechanical and limit equilibrium models should be more clearly articulated to ensure transparency and understanding.
- The paper would benefit from a more detailed discussion on the validation of the proposed models. Were simulations or experimental studies conducted to verify the results? Addressing this would help confirm the robustness of the models.
- While the results are promising, the discussion could delve further into the practical challenges of implementing flexible reinforcement technology in mining operations, particularly in terms of scalability and cost.
- The conclusion reiterates the findings but could focus more on specific outcomes and their broader implications for mining safety and sustainability. A stronger conclusion would better highlight the study's contributions to the field.
- It would be helpful to include a section that suggests areas for further research, such as testing the model’s applicability to different geological settings or considering additional factors, such as dynamic loading, which may influence the model’s effectiveness in real-world conditions.
Author Response
Comment 1: Some sentences are long and complex, making them difficult to follow. Simplifying technical jargon where possible could improve clarity.
Response: Thank you very much for this suggestion. We have simplified technical jargon and shorten the sentences in the revised manuscript.
Comment 2: The abstract could more clearly summarize the key findings and their implications, making the study’s contributions more accessible to a wider audience.
Response: Thank you very much for this suggestion. We have reorganized the key findings and implications in the abstract of the revised manuscript.
Comment 3: The inclusion of specific values or percentages related to the findings would strengthen the results and provide more concrete evidence.
Response: Thank you very much for this suggestion. The safety stability factor in this paper is a coefficient or percentage of coal wall stability. After reinforcement, the stability factor at the most dangerous locations was increased from 0.09 to 1.03. In addition, the actual application in the field shows that the coal wall does not have coal wall spalling after reinforcement.
Comment 4: The introduction reviews prior research but lacks a clear problem statement outlining the research gap this study addresses. A more explicit identification of the gap would help clarify the paper's significance.
Response: Thank you very much for this suggestion. We've revised the introduction to include a question statement (line 58-59 and 84-86 in the introduction of the revised manuscript).
Comment 5: Some of the cited literature is relatively outdated. Incorporating more recent studies would enhance the paper’s credibility and demonstrate a more comprehensive review of the current state of research.
Response: Thank you very much for this suggestion. We have removed outdated literature and added cited literature about more recent studies (the reference 2, 3, 6, 15, 23, 24, 26, 30, and 31).
Comment 6: The assumptions made in the mechanical and limit equilibrium models should be more clearly articulated to ensure transparency and understanding.
Response: Thank you very much for this suggestion. We have added the basic assumptions of the mechanics and limit equilibrium model in the revised manuscript (line 135-141 in the section 2.1 of the revised manuscript).
Comment 7: The paper would benefit from a more detailed discussion on the validation of the proposed models. Were simulations or experimental studies conducted to verify the results? Addressing this would help confirm the robustness of the models.
Response: Thank you very much for this suggestion. The proposed model has been validated in the field, and it is already mentioned in section 4.4 (Fig. 15). After flexible reinforcement, the stability of the coal wall is improved, and there is no coal wall spalling. Our future research will include numerical simulations or experimental studies.
Comment 8: While the results are promising, the discussion could delve further into the practical challenges of implementing flexible reinforcement technology in mining operations, particularly in terms of scalability and cost.
Response: Thank you very much for this suggestion. We have added the discussion about the cost and scalability of flexible reinforcement technology in practical applications (line 430-437 in the section 4.5 of the revised manuscript).
Comment 9: The conclusion reiterates the findings but could focus more on specific outcomes and their broader implications for mining safety and sustainability. A stronger conclusion would better highlight the study's contributions to the field.
Response: Thank you very much for this suggestion. We have revised our conclusions to include references to mine safety and sustainability.
Comment 10: It would be helpful to include a section that suggests areas for further research, such as testing the model’s applicability to different geological settings or considering additional factors, such as dynamic loading, which may influence the model’s effectiveness in real-world conditions.
Response: Thank you very much for this suggestion. We've added a discussion about model limitations and future research (line 413-429 in the section 4.5 of the revised manuscript). In the future research, we will continue to study these shortcomings.
Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report
Comments and Suggestions for AuthorsThe authors have made the requested revisions and the manuscript can be accepted.
Author Response
Comments: The authors have made the requested revisions and the manuscript can be accepted.
Response: Thank you very much for reviewing this manuscript, your comments have been of great help to improvement of the manuscript. In addition, we have made corrections to the structure and the expression of the manuscript and added some deductions and practical suggestions to the conclusion. Improvements and clarifications have been made in the current manuscript. These changes are marked in red.
