YUAN R F, LI H, DONG Z,et al.Failure evolution mechanism of the end-area hanging roof of a coal mining face under static fracturing effects[J].Journal of Henan Polytechnic University(Natural Science) ,2026,45(2):54-63.

doi:10.16186/j.cnki.1673-9787.2024120020

Received:2025/03/09

Revised:2025/07/24

Published:2026/01/28

Failure evolution mechanism of the end-area hanging roof of a coal mining face under static fracturing effects

Yuan Ruifu1,2,3, Li Hui1,2, Dong Zhuo1, Zhang Qunlei1

1.School of Energy Science and Engineering， Henan Polytechnic University， Jiaozuo  454003， Henan， China；2.Collaborative Innovation Center of Coal Work Safety and Clean High Efficiency Utilization， Jiaozuo  454003， Henan， China；3.Zhengzhou Institute for Advanced Research of Henan Polytechnic University， Zhengzhou  451464， Henan， China

Abstract: Objectives To reveal the failure evolution mechanism of the end-area hanging roof of a coal mining face and to achieve rational mine pressure control， this study investigates the static fracturing failure characteristics of the hanging roof and determines the optimal drilling spacing. Methods A numerical model of end-area hanging roof failure was established using the Continuous-Discontinuous Element Method （CDEM） to analyze the static fracturing failure characteristics. Based on the geological conditions of the 5-2 coal seam in a representative mine， a numerical model of the strata in the end area of the working face was constructed to investigate the deformation and fracture processes of the hanging roof before and after static fracturing during excavation， thereby revealing the failure evolution mechanism under the action of static cracking agents. Results The results indicate that the expansion pressure of the static cracking agent is positively correlated with the tensile strength of the hanging roof. When the tensile strength is lower than 8 MPa and the expansion pressure is ≥30 MPa， optimal fracturing performance is achieved. The optimal drilling spacing for hanging roof fracturing is 1.25 m. Before static fracturing， the periodic caving interval of the end-area hanging roof ranges from 37.5 m to 22.5 m， with an average interval of 27.5 m. After static fracturing， the periodic caving interval is reduced to 17 m to 12 m. Field measurements of support resistance and roof displacement further verify the feasibility of the static fracturing technique.  Conclusions By regulating the caving interval and fracture sequence of the hanging roof， static fracturing technology can effectively mitigate safety hazards induced by sudden mine pressure variations. The findings provide theoretical guidance for the engineering application of static fracturing technology in hard roof control.

Key words: end-area hanging roof; static fracturing; roof cutting and pressure relief; numerical simulation; failure evolution mechanism