LIU Z M, CHEN Y, LI H,et al.Seepage diffusion and application of advanced grouting in Kilometer-deep mines[J].Journal of Henan Polytechnic University(Natural Science) ,2026,45(2):166-174.

doi:10.16186/j.cnki.1673-9787.2024040033

Received:2024/04/18

Revised:2024/07/11

Published:2026/01/28

Seepage diffusion and application of advanced grouting in Kilometer-deep mines

Liu Zhengmao1, Chen Yan2, Li Hu1, Liu Qingbo3, Zhang Zhiliu1, Zhu Yangtao1, Meng Qingbao1, Li Shuai1, Zong Chengbo1, Wang Jiahao2

1.China Coal Xinji Fuyang Mining Co.， Ltd.， Fuyang  236153， Anhui， China；2.Collaborative Innovation Center of Coal Work Safety and Clean High Efficiency Utilization， Henan Polytechnic University， Jiaozuo  454003， Henan， China；3.China Coal Xinji Energy Co.， Ltd.， Huainan  232001， Anhui， China

Abstract: Objectives Rib failure and roof collapse in deep， soft-rock coal faces under ground pressure are addressed through investigation of seepage diffusion laws and field application of advance grouting for kilometer-deep mining.  Methods Taking the 140504 working face of Kouzidong Mine as a case study， a fan-shaped grouting hole layout is designed for advance roof reinforcement with cement slurry. Using COMSOL Multiphysics， the variations in slurry diffusion radius and grouting pressure over time under double-hole grouting are simulated. FLAC3D is then employed to compare the vertical displacement of the surrounding rock before and after grouting， thereby evaluating the reinforcement effect.  Results The results show that： （1） the slurry diffuses concentrically， with the highest concentration at the grouting hole， decreasing axisymmetrically outward； the diffusion radius increases nonlinearly with time. （2） The maximum diffusion radius is attained after 17 h of grouting. By varying the final hole spacing based on this radius， three reinforcement scenarios—overlapping， tangent， and separated diffusion zones—are simulated； the tangent condition is adopted to determine the optimal grouting hole spacing. （3） The grouting pressure remains nearly constant near the injection point， then drops sharply and stabilizes symmetrically toward both sides. （4） Simulation indicates that roof grouting reduces the maximum vertical displacement by 21.4%， demonstrating effective control of overlying-strata movement. （5） Field practice confirms that grouting reinforcement significantly reduces personnel requirements and increases the monthly face-advance rate by 62.4%. Based on actual grouting data， the final hole pressure should be no less than 8 MPa.  Conclusions The findings provide a practical reference for the design and implementation of advance grouting reinforcement in kilometer-deep coal faces.

Key words: pre-grouting; slurry diffusion; grouting pressure; end hole spacing; thousand meters deep mine