**5. Conclusions**

A dynamic risk assessment method of high slope in open-pit coalmine based on interval trapezoidal fuzzy soft set has been proposed for realizing dynamic early warning of high slope risk in open-pit coalmine. The proposed dynamic interval trapezoidal fuzzy soft set method integrates time points and the weights of slope risk factors. The formulations of the proposed method are derived, along with a detailed introduction to the procedures for implementation. Finally, the method is illustrated by a case study of high slope in Shengli #1 open mine located in Xilinhot, Inner Mongolia to verify the effectiveness of the proposed method. The main conclusions are summarized as follows:


at different time ranges are analyzed; the results show that the above-mentioned slope dynamic evaluation model and method are reasonable and effective. In the process of slope reinforcement at the later stage for Shengli #1 open-pit mine, the influence of hydrological and climatic conditions and geometric shapes should be evaluated.

**Author Contributions:** Conceptualization, Z.W., M.H. and P.Z.; methodology, Z.W. and P.Z.; software, M.H.; validation, X.L. and S.Y.; formal analysis, Z.W.; investigation, P.Z., X.L. and S.Y.; data curation, P.Z.; writing—original draft preparation, Z.W., M.H. and P.Z.; writing—review and editing, Z.W.; funding acquisition, Z.W. and X.L. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research was funded by Scientific and Technological Project of Henan Province (222102320060), Strength Improvement Plan of the Advantageous Disciplines of Zhongyuan University of Technology (SD202232), Henan Postgraduate Education Reform and Quality Improvement Project (YIS2022SZ16), Postgraduate Education Reform and Quality Improvement Project of Zhongyuan University of Technology (JG202220).

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** Not applicable.

**Conflicts of Interest:** The authors declare no conflict of interest.

#### **Appendix A**

**Table A1.** Risk assessment index system and classification standard for slope of open-pit coal mine.



**Table A2.** The different risk evaluation values subordinated by influencing factors of *B*<sup>1</sup> at time *t*1.

**Table A3.** The different risk evaluation values subordinated by influencing factors of *B*<sup>2</sup> at time *t*1.


**Table A4.** The different risk evaluation values subordinated by influencing factors of *B*<sup>3</sup> at time *t*1.


**Table A5.** The different risk evaluation values subordinated by influencing factors of *B*<sup>4</sup> at time *t*1.


**Table A6.** The different risk evaluation values subordinated by influencing factors of *B*<sup>1</sup> at time *t*2.


**Table A7.** The different risk evaluation values subordinated by influencing factors of *B*<sup>2</sup> at time *t*2.



**Table A8.** The different risk evaluation values subordinated by influencing factors of *B*<sup>3</sup> at time *t*2.

**Table A9.** The different risk evaluation values subordinated by influencing factors of *B*<sup>4</sup> at time *t*2.


**Table A10.** The different risk evaluation values subordinated by influencing factors of *B*<sup>1</sup> at time *t*3.


**Table A11.** The different risk evaluation values subordinated by influencing factors of *B*<sup>2</sup> at time *t*3.


**Table A12.** The different risk evaluation values subordinated by influencing factors of *B*<sup>3</sup> at time *t*3.


**Table A13.** The different risk evaluation values subordinated by influencing factors of *B*<sup>4</sup> at time *t*3.



**Table A14.** The influencing factors of *B*<sup>1</sup> in the whole time period belong to the comprehensive evaluation value of different risks.

**Table A15.** The influencing factors of *B*<sup>2</sup> in the whole time period belong to the comprehensive evaluation value of different risks.


**Table A16.** The influencing factors of *B*<sup>3</sup> in the whole time period belong to the comprehensive evaluation value of different risks.


**Table A17.** The influencing factors of *B*<sup>4</sup> in the whole time period belong to the comprehensive evaluation value of different risks.


**Table A18.** Fuzzy symmetric matrix for influencing factors of hydrology-climate *B*1.



**Table A19.** Fuzzy symmetric matrix for influencing factors of geological structure in slope *B*2.

**Table A20.** Fuzzy symmetric matrix for influencing factors of slope geometry condition *B*3.


**Table A21.** Fuzzy symmetric matrix for inducing factors *B*4.


**Table A22.** Fuzzy symmetric matrix corresponding to first level index.


**Table A23.** The integrated evaluation value of different parameters belonging to open-pit slope risk.


**Table A24.** Integrated value of surface mine slope risk relative to different risk grades.


#### **References**


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