XU L,  WANG S Y,  ELMO Davide, et al. Compression-consolidation-creep-diagenesis process of compacted gangue and analysis of its equivalent mining height model[J]. Journal of Henan Polytechnic University(Natural Science) , 2024, 43(6): 27-37.

doi：10.16186/j.cnki.1673-9787.2023060045

Received: 2023/06/19

Revised: 2023/08/03

Online: 2024/09/24

Compression-consolidation-creep-diagenesis process of compacted gangue and analysis of its equivalent mining height model

XU Lei1,2,  WANG Siyu1,  ELMO Davide3,  DING Shuxue1,  LIU Honglin4,  LI Wenfeng5,  HONG Zijie1

1. School of Civil Engineering, Henan Polytechnic University, Jiaozuo 454000, Henan, China； 2. International Joint  Research Laboratory of Henan Province for Underground Space Development and Disaster Prevention, Henan Polytechnic University, Jiaozuo 454000, Henan, China； 3.  Norman B. Keevil Institute of Mining Engineering, University of British Columbia, Vancouver, BC V6T 1Z4, Canada； 4. School of Geology and Mines Engineering, Xinjiang University, Urumqi 830046, Xinjiang, China； 5. Earth and Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, NM 87545, United States

Abstract: Objectives This study aims to investigate the compression-consolidation-creep-diagenesis process of compacted gangue and its equivalent mining height model, using the 1102 gangue filling face of Tingnan Coal Mine as the engineering background. Methods The research employed theoretical analysis, numerical simulation, laboratory tests， and field measurements. Results The findings show that the maximum roof control distance of the gangue filling face is the sum of the cutting depth, end face distance, top beam length, and the contact distance between the rear support and the gangue. The rotational subsidence of the roof equals the maximum roof control distance multiplied by the sine of the support’s tilt angle (h_t=L_max×sinθ). The backfill space height behind the support equals the mining height minus the roof’s rotational subsidence, the underconnection amount, and the bottom heave behind the frame. The compression-consolidation-creep-diagenesis process of compacted gangue in the backfill space comprises four stages with the following compression rates: skeleton adjustment stage (7.42%), slow compression stage (5.39%), consolidation settlement stage (0.34%), and creep-diagenesis stage (12.38%). The equivalent mining height for the 1102 face across these four stages is: skeleton adjustment stage (0.94 m), slow compression stage (1.10 m), consolidation settlement stage (1.11 m), and creep-diagenesis stage (1.48 m). Conclusions Comparisons of the probability integration method prediction, numerical simulations,  and subsidence observations revealed that the surface subsidence curves of the main cross-section along the strike and dip directions of the 1102 working face exhibit a bowl-shaped profile. The surface subsidence curves are gentle during the first two stages and steep during the latter two.

Key words:  gangue filling; equivalent mining height; gangue compression; consolidated diagenesis