Analyzing the Synchronous Acoustic and Electric Response of Coal Burst Failure: Validation through the On-Site Application

Round 1

Reviewer 1 Report

The R value index of the paper is innovative, and the prediction of coal and rock dynamic disaster is of practical significance. In general, the paper is some good at writing, methodology and diagram display, but there are still some major problems and some Suggestions:

(1) there should be a parameters and lithological description of the samples of the test in the form of the form.

(2) the x and y coordinates of Figure 2(a) are not clear.

(3) What is the EME that pops up in 3.2? What is the difference with the aforementioned AMR?

(4) The physical components observed by the instrument should be indicated in the test, and what are the relationships to EMR and AE? The theoretical background of parameters calculation should be clarified.

(5)From Figure 4, it is hard to see where M is. It's not represented on the axes, right?

(6) Is R index self-proposed? What's the rationale?

(6) The English writing level of the article needs to be improved.

Author Response

Dear Reviewers:

On behalf of my co-authors, we thank you very much for giving us an opportunity to revise our manuscript, we appreciate editor and reviewers very much for their positive and constructive comments and suggestions on our manuscript. We have studied reviewer’s comments and editor suggestion carefully and modified the paper with the review mode. Please refer to the attachment for the main corrections in the paper and the replies to the reviewers' comments.

Author Response File: Author Response.docx

Reviewer 2 Report

Review of “Analyzing the synchronous acoustic and electric response of coal-rock burst failure: validation through the on-site application” by Zhao et al.

 

General comments:

This paper presents the assessment of rock failure risk using Acoustic Emission (AE) and Electromagnetic Energy (EME) measurement technologies. The authors characterized the correlations AE/EME signals and the rock failure process (i.e., elastic-, yield-, plastic-, and failure-stages) using the core samples with the different physical properties obtained from the mines. Then, the proposed method was applied to the actual mine, and compared with the seismic anomalies. The authors introduce the ratio of the signal energy to the number reflecting the where the stress of coal rock during the loading (i.e., the M value). However, the interference noise may contaminate the AE/EME signals. To circumvent this issue, the authors propose new index (i.e., the R value) to evaluate the risk of rock failure based on the AE/EME measurements, and I guess this can contribute to the assessment of rock failure risk. I feel that the number of the core sample for the examination was a few (only 6 samples for the laboratory experiment) to generalize the application to the in-situ AE/EME measurements and no evidence of rock failure was observed in the field so far. Nevertheless, this paper is interesting and highlights the potential added values of AE/EME measurements for monitoring/assessment of the rock failure risk. Overall, I think this paper would be published in the journal once some concerns/questions are addressed.

 

As for the on-site verification of the proposed R values, is the basic physical properties (e.g., P-wave and S-wave velocities) for the Jin Jia mine similar to those of Kuangou and Tashan samples employed in the laboratory experiment? I think if the sample from the Jin Jia mine was used, the paper is more persuasive.

 

 

Line comments:

Lines 126 – 127: In general, elastic energy conserved in a sample is defined by the area for which stress times deformation, and therefore the elastic energy of Kuangou samples has larger than that of Tashan’s ones except for T3 sample. Can you confirm the description here whether it is correct?

 

Lines 129 – 130: The term of “rockburst” is repeated for two different mechanism of coal-rock failure by an external loading, which may confuse readers. Can you say “rock collapse” or simply “rock failure” for the latter “rockburst”?

 

Line 135: Abbreviation “EME” should be defined at the first use in the article.

 

Line 143: Is “the strain strengthened area” same as “strain hardening zone” in Fig. 2? If so, the expression of Fig. 2 should be revised as used in the text. The same concern is raised at Line 121.

 

Line 146: How did you identify the T2 sample shifted the elastic to strengthened area at 150 s? The black line shows the stress increase with time smoothly over time until the yield point at 200 s.

 

Lines 157 - 158: Can you generalize this for the strengthened area? Is it really correlated in frequency between the AE and EME? I see the AE has much more energy, counts, and frequencies than the EME in the strengthened area for both the K1 and the T2 samples.

 

Line 172: It is difficult to follow the phrase starting with “The graph was enlarged …” I guess that this intends that red marks were added when the value of M > 1.

 

Line 202: R value mentioned before the definition by Eq. (2). I recommend the authors to revise this para, with separating R value.

 

Line 211: Should “m value” be “M value”.

 

Line 226: Isn’t “Jin jia” to be “Jin Jia”? I am not familiar with the regional town name.

 

Line 238: How long did you measure AE and EME for each site? Duration of measurement should be provided here. Is this AE/EME acquisition a permanent observation system during the operation for the Jin Jia mine?

 

Line 247: Should “Figure 11” be “Figure 10”.

 

Lines 263 – 264: A negative anomaly (i.e., < -0.25 ) is identified at a distance from 260 – 300 m; however its effect seems very little in the AE/EME correlate events and the R values. The authors should mention this and discuss with a few wording. Can this negative anomaly affect the authors’ interpretation?

 

Line 302: “6. Patents” should be moved to a new line or deleted here.

 

Figures 8 & 11: Can you add a legend for distance scale?

 

Figure 12: Captions for axis (i.e., length in meters) may be needed.

 

 

Author Response

尊敬的审稿人：

 

我们代表我的合著者，非常感谢您给我们机会修改我们的手稿，我们非常感谢编辑和审稿人对我们手稿的积极和建设性的意见和建议。我们仔细研究了审稿人的意见和编辑建议，并以审稿模式修改了论文。论文主要更正及审稿人意见回复见附件。

Author Response File: Author Response.docx

Round 2

Reviewer 1 Report

All my amendments have been responded to.