Review Reports

Round 1

Reviewer 1 Report

I have reviewed the manuscript titled "Shear strength and energy evolution of granite under real-time temperature" and found it to be a valuable contribution to the field of rock mechanics. However, I suggest some minor revisions and improvements to the manuscript to enhance its clarity and impact.

1-The abstract needs to be more concise and clearer. It should provide a brief summary of the research problem, methodology, and key findings. I suggest rewriting it.

2-The manuscript needs to provide more information on the practical implications of the findings. Specifically, the authors should discuss how the results can be used to improve deep underground rock engineering design and operations. Also, some limitations of the study should be mentioned, and directions for future research could be suggested.

3- The current conclusion section is repetitive, and the information is already presented in the results section. Please rewrite.

 

I believe that these minor revisions and improvements will enhance the manuscript's clarity and impact, making it a more valuable contribution to the field of rock mechanics.

 Minor editing of English language required

 

Author Response

Please see the attachment.

Author Response File: Author Response.docx

Reviewer 2 Report

Based on the rock shearing test under high temperature and high pressure and the acoustic emission (AE) technique, the authors discussed the evolution of macroscopic mechanical properties, AE characteristics and surface morphology of granite under real-time high temperature. The research results have great significance for the deep underground rock engineering. I think the manuscript is well written. There are several suggestions for the manuscript.

 

1. The rock mechanics experiments were carried out at 25℃, 100℃, 200℃, 300℃, and 400℃ with normal stresses of 10 MPa, 20 MPa, 30 MPa, and 40 MPa. Which means that authors considered the influences of both temperatures and pressures on macroscopic mechanical properties. In fact, the authorss focus was still on temperature, and the discussion of experimental results mainly focused on temperature. However, due to the consideration of pressures, there are some differences in the evolution of macroscopic mechanical properties such as shear stress-displacement under different pressures. Suggesting that the differences in the evolution of macroscopic mechanical properties caused by pressures should be better explained.

2. For some discussions of the evolution of macroscopic mechanical properties, it is recommended to supplement direct evidence. For example, “Before 200 ℃, the water inside the granite sample is heated and evaporated, resulting in a weakening of the bonding force between the mineral particles, but at the same time, the interaction between the mineral particles is enhanced due to thermal expansion, so that the shear modulus decreases slowly with increasing temperature.” CT scanning or other experiments can be considered to verify the authors’ viewpoint about a weakening of the bonding force between the mineral particles.

3. the curves at various temperatures under different normal stresses were divided into five stages. As shown in Figure 4, these five stages are not obvious, especially, at different temperatures, the timing of the five stages occurring is not uniform. it is recommended to further clarify the stage division.

4. The acoustic emission are an important testing method that can assist in understanding evolution of macroscopic mechanical properties. However, in section 3.4, the authors’ focus of AE energy was still on AE energy itself and of course, involves micro-cracks. The stage division of the change in AE energy is also inconsistent with the five stages of the evolution of macroscopic mechanical properties. It is recommended to combine the stage division of mechanical properties more closely and use the AE energy to provide a detailed explanation of the evolution of mechanical properties.

5. The surface morphology of granite shown in Figure 8 is not clear. Meanwhile, the variation characteristics of surface morphology cannot represent internal variation characteristics. It is recommended to use other CT scans and other experiments to visually observe internal variation characteristics.

Author Response

Please see the attachment.

Author Response File: Author Response.docx