Analysis of Impact Tendency and Sensitivity of Fractured Rock with Different Crack Arrest Measures
Round 1
Reviewer 1 Report
This paper presents a valuable study on the analysis of impact tendency and sensitivity of cracked rock with different crack arrest measures. The selection of this subject has a certain practical and academic value. These methods are detailed and reliable, and the conclusions are supported. Meanwhile, the paper has good logic, and I feel that it is very suitable for publication.
However, it is suggested that the author supplement or improve the following problems:
1. The author uses the PFC numerical simulation software to simulate cracked rocks with different crack numbers under different arrest measures. Please explain the characteristics of PFC and why PFC is selected for simulation research.
2. In the 3.2 section, it is concluded that the cracks generated in the rock specimen grow in steps, which needs to be explained. It is necessary to explain the reasons for the growth in step development of the cracks.
3. Figs. 9-11 is the direction of crack propagation of cracked rocks with different crack numbers under different arrest measures. The reasons for different fracture propagation directions of different cracked rocks with different crack arrest measures should be explained, and the distribution law of fracture propagation direction should be summarized.
4. In the description of failure characteristics in Fig. 13, "the growing anchored crack area measures form a certain range of anchoring area around the growing crack and the bolt", the influence of different crack arrest measures on the formation of anchoring area should be explained.
5. In the 4.2 section, the impact energy index of cracked rocks with different crack arrest measures is analyzed, and the reason for the influence of crack arrest measures on the variation trend of the impact energy index should be added.
6. The font size in Fig. 6, Fig. 7, and Fig. 12 in the paper should be the same standard as the fonts in other figures.
7. In the introduction, the references should be arranged in chronological order. Therefore, please modify the corresponding research contents.
8. The conclusion in the paper is too complicated, so the conclusion in the paper should be properly modified to make it refined.
9. References’ format is not unified and consistent. And some volume number of references were missed. In addition, there was some inconsistent writing format of the journal name. Besides, the language in this article should better be carefully checked and improved.
Author Response
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Author Response File: 
Author Response.pdf
Reviewer 2 Report
The paper does not indicate where the rock samples were taken from. There is no information about the type and type of rocks, petrographic composition, or geological conditions of rock occurrence.
Without reference to geological information, the results of the experiment do not make sense.
The article is a targeted work to account for the funding of the research project with a publication.
It could be a student paper and not a researcher working on a very important issue affecting the safety of coal mining.
Author Response
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Author Response File: Author Response.pdf
Reviewer 3 Report
Reviewer Comments
Paper title: Characterization of Tensile Crack Propagation and Energy Evolution During the Failure of Coal-Rock Samples Containing Holes
The present manuscript studied and analyzed the crack arrest effect of the grouting crack arrest measure, the anchoring crack arrest measure and the grouting anchored crack arrest measure. The crack propagation laws and sensitivities of cracked rocks with different arrest measures are compared and analyzed.
Of course it has a practical implication as the research results of this paper provide some guidance for the selection of crack arrest parameters and scheme design in practical rock engineering.
The paper can be accepted for publication after providing the corrections mentioned below.
Point 1. The abstract section sounds clear and follows the MDPI style of structured abstracts, but it would be perfect if the authors consider showing the novelty in the abstract. If there is no such opportunity, please indicate the novelty of the study in the conclusion section.
Point 2. The introduction section seems to be informative but not too short. In-deep literature review is required. It will be great if the authors show some description in context – Why it is important to conduct this study? Can the expected result be used or implemented within other conditions? If yes, then how? What limitations?
Point 3. The aim and the tasks must be highlighted at the end of the Introduction section.
Point 4. It is recommended to use Materials and methods instead of “Parameter selection and model building”
Point 5. Line 92. Authors indicate: “The model size is φ50 × 100 mm” Whys such dimensions were chosen? And, what about the scale effect?
In this context, please consider the reference mentioned below https://doi.org/10.33271/mining14.04.024
Point 6. Section Materials and methods needs more detailed description.
Point 7. It is recommended to use Results and discussion instead of “Experimental result”
Point 8. Is it possible to place formulas (1)-(3) on the Figure 6?
Point 9. Is it possible to place formulas (4)-(6) on the Figure 7?
Point 10. Is it possible to place formulas (7)-(9) on the Figure 12?
Point 11. It is recommended to place section 4 (Impact energy index) in the Section 3.
Point 12. Is it possible to place formulas (10)-(12) on the Figure 16?
Point 13. Place figure 17 after first mentioned in the text.
Point 14. Please provide a short description of further research.
Point 15. Delete dots before the paragraphs in the conclusion section.
Point 16. There is a paper that I would like to bring to your attention. Please consider the suggested research in your paper when enhancing the literature review in the context of crack influence on mining operations.
Krykovskyi, O., Krykovska, V., & Skipochka, S. (2021). Interaction of rock-bolt supports while weak rock reinforcing by means of injection rock bolts. Mining of Mineral Deposits, 15(4), 8-14. https://doi.org/10.33271/mining15.04.008
Point 17. Finally, I must admit that a very good study was performed, and I will recommend your paper for publication after careful revision.
Author Response
Please see the attachment.
Author Response File: Author Response.pdf
Round 2
Reviewer 2 Report
Corrections to the text and explanation largely realize the reviewer's comments. In its current form, the text at a basic level fulfills the conditions for printing an article.
Reviewer 3 Report
Dear authors,
I am more than satisfied with the corrections provided by you.
This study is an important contribution to sustainable mining.
Congratulations to the authors.
