ZHANG G C, LIU Y H, YIN M S,et al.Dynamic fracturing effects of the immediately overlying thick， hard roof in deep mining and the stability mechanisms of gob-side roadways[J].Journal of Henan Polytechnic University(Natural Science) ,2026,45(2):86-96.

doi:10.16186/j.cnki.1673-9787.2025080022

Received:2025/08/15

Revised:2025/10/30

Published:2026/01/28

Dynamic fracturing effects of the immediately overlying thick， hard roof in deep mining and the stability mechanisms of gob-side roadways

Zhang Guangchao1, Liu Yuhang1, Yin Maosheng1, Zhang Zhaoyun2, Zheng Canguang2, Zhang Ronggang1, Lei Teng1, Zhao Xipo2

1.College of Energy and Mining Engineering， Shandong University of Science and Technology， Qingdao  266590，  Shandong， China；2.Yankuang Energy Group Co.， Ltd.， Jining  272000， Shandong， China

Abstract: Objectives To address impact-induced instability of gob-side roadways beneath immediately overlying thick， hard roof in deep mining faces of the Yanzhou mining area，  the transport roadway of the 18306 working face in Jisan Coal Mine is taken as the engineering background to investigate the underlying disaster mechanisms and propose effective control technologies.  Methods A comprehensive approach integrating field investigation， theoretical analysis， numerical simulation， and in-situ testing is employed. A cantilever-beam mechanical model of the immediately overlying thick， hard roof is established to systematically analyze its mining-induced load-bearing behavior and the evolution characteristics of energy accumulation. The influences of roof properties on the catastrophic instability of gob-side roadways are revealed， and the definition and evolutionary process of dynamic instability under thick， hard roof conditions are clarified. On this basis， a layered collaborative control system integrating variable-diameter borehole sealing and coupled roof anchoring–grouting reinforcement is proposed and implemented. Results 1. The accumulation and distribution of mining-induced energy in thick， hard roof strata are significantly influenced by their inherent geological and mechanical properties. Higher roof strength and greater thickness correspond to lower peak bending energy and weaker energy concentration， whereas longer roof suspension lengths and greater overlying loads result in higher peak bending energy accumulation and a more extensive high-stress zone. 2. Dynamic instability of deep roadways essentially results from rapid energy release and structural degradation of surrounding rock under strong dynamic disturbances induced by thick， hard roof fracturing， typically manifested as coal ejection and support system failure. 3. A layered collaborative control strategy combining pressure relief through variable-diameter borehole sealing and roof anchoring–grouting reinforcement is developed， forming a targeted protection system for immediately overlying thick， hard roofs.  Conclusions Field tests demonstrate that the proposed technology effectively ensures the stability of surrounding rock in gob-side roadways beneath immediately overlying thick， hard roofs， providing a valuable reference for support design in similar roadway conditions.

Key words: dynamic instability; immediately overlying thick， hard roof; gob-side roadway; dynamic disaster; layered collaborative support