Research on Rheological Energy Characteristics of Fractured Sandstone Strengthened with CFRP
Round 1
Reviewer 1 Report
The excavation of underground engineering can easily lead to the cracking and even destruction of surrounding rock. The study on the rheological characteristics of fractured rock mass has a strong engineering significance for analyzing the stability of surrounding rock. In this paper, the characteristics of energy dissipation in the rheological process of fractured sandstone reinforced by CFRP are analyzed through the graded loading rheological test, and the working mechanism of the reinforced structure in the rheological process is revealed, which has a guiding role for the rheological failure analysis of reinforced rock in practical engineering.
1.In this paper, it is not appropriate to determine the reinforced area by using the reinforced intact sandstone sample. Since the fractured samples were obtained by fracturing the intact sandstone samples, the method of comparing the stress-strain curves of the reinforced fractured samples and the intact sandstone samples is suggested to determine the reinforcement area, and the author is requested to explain and improve it.
2. In Section 2.2, the stress level in the flow process of fractured sandstone strengthened by CFRP is divided into low stress, medium stress and high stress. What is the basis for the classification? Is it creep rate, damage, something else?
3. “4.1. Analysis of global energy evolution” should be“4.1 Energy evolution analysis of rheological processes”
4. In Section 4.2, the last sentence "And almost no damage occurs in the sandstone" has no logical relation to the preceding, where does this conclusion come from?
5. The ratio of elastic energy Ue to dissipated energy Ud under arbitrary stress is defined as the damage variable, and the resulting damage variable value is greater than 1, which is inconsistent with the meaning of conventional damage, and it is doubtful. Please explain the basis and physical meaning.
6. Many sentences are not accurate enough, and it is suggested to polish the language.
Author Response
请参考附件。
谢谢审稿人。
Author Response File: 
Author Response.pdf
Reviewer 2 Report
The authors report a study on the rheological energy characteristics of fractured sandstone strengthened with CFRP. The manuscript is well written and can be published in the Sustainability prestigious journal. However, this manuscript needs some revisions prior to acceptance. Below, the authors can find some advice that can help improve the structure of their article.
#1 Abstract: Every abstract should contain relevant information that summarizes the work. Please add more quantitative information to the abstract. I recommend authors use the following reference (Good reading) to adjust their abstract.
(https://doi.org/10.1016/j.carbon.2007.07.009).
#2 There are several typographical and grammatical mistakes which should be corrected. eg., unnecessary comma and typo mistakes. Please carefully revise it.
#3 The novelty of the work is not expressed explicate. In what aspect is this work original and better than others? Please try to be clearer about the novelty of the work.
#4 The last paragraph of the introduction must also be dedicated to explain the main goal of the work not a summary of what will be presented in the manuscript. Please make clear the purpose of the work. Rewrite the last paragraph of the introduction.
#5 Although the conclusion can be writing by more than 1 item, it must be written in a single running paragraph.
Author Response
请参阅附件。
谢谢审稿人。
Author Response File: Author Response.pdf
Reviewer 3 Report
Dear Authors,
The topic covered in the manuscript “Research on rheological energy characteristics of fractured sandstone strengthened with CFRP” is quite an interesting topic in terms of determining of properties and rheological energies of fracture sandstone. Unfortunately the manuscript is not without ambiguities.
First of all, in the introduction section Authors give a huge range of methods for determining the properties of sandstone, pointing out that the topic has been studied in depth in the literature. Hence, the motivation for taking up the topic of rheological energy research is unclear. Also, the reason for using exactly the CFRP method for the study was not explained.
The section Materials and Methods lacks an indication of the load pattern.
Although the manuscript has a classic section breakdown, the information contained in each section is not presented in the corresponding sections. For example, Tables 2 and 3 are presented experimental results but are presented in section Materials and Methods.
Description od schematic loading discussed after Table 3 is not clear, Fig. 5 also does not clarify this issue. Maybe there is a point in applying particular loads given as a text on the figure.
In my opinion, the manuscript can present quite interesting results under the condition that the article is improved and refined.
Best regards
Author Response
Please see the attachment.
Thank you, reviewer.
Author Response File: Author Response.pdf
Round 2
Reviewer 3 Report
The authors took into account most of my comments
