The effects of dynamic pressure on the stability of prepared drifts near the working surface areas
- Authors: Nhan Thi Pham *, Nghia Viet Nguyen
Hanoi University of Mining and Geology, Vietnam
- Keywords: Auxiliary tunnel, Coal pillar, Displacement, Pressure.
- Received: 25th-Oct-2020
- Revised: 23rd-Jan-2021
- Accepted: 6th-Feb-2021
- Online: 28th-Feb-2021
- Section: Mining Engineering
Due to the effects of dynamic pressure, the stress distribution of rock mass is very complex. The reason for this could be a risk of stability loss for an auxiliary tunnel system constructed within the study area. In this article by using Flac3D software the author simulated two adjacent working faces with the thickness of 5 m natural coal pillar. Three factors: the upper working face excavation process, auxiliary tunnel mining process, and the location of lower working face, affected by deformation, stress distribution, safety of lower floor area and surrounding rock mass of tunnel. The research results show that during the excavation, the mechanical behavior of the rock mass surrounding the auxiliary tunnel showed displacements, volatility, and phase characteristic. The displacement on the auxiliary tunnel boundary in both excavation and working face cases showed that the roof and the left side wall displacement was greater than the right side wall and the bottom. Therefore, the distance between the auxiliary tunnel and the empty mining space needs to be computed to meet technical and economic requirements.
Bai Jian Biao, (2002). Nghiên cứu nguyên lý và công nghệ điều khiển ổn định khối đá xung quanh đường lò chuẩn bị khi khai thác bằng cơ giới hóa hoàn toàn. Luận văn tiến sĩ, Đại học Mỏ Công nghệ, Từ Châu, Trung Quốc.
Itasca (2005). Flac Fast Lagrangian analysis of continua. User’s guide. Third edition.
Heping, Xie, Gao Feng, and Ju Yang (2015). Research and development of rock mechanics in deep ground engineering. Chinese Journal of Rock Mechanics and Engineering 34.11: 2161÷2178.
Nguyễn Phi Hùng và nnk, (2020). Giải pháp nâng cao hiệu quả chống giữ cho lò chợ cơ giới hóa vỉa 6 mỏ than Nam Mẫu. Tạp chí khoa học kỹ thuật Mỏ - Địa chất. Tập 61, kỳ 1, tr116÷123.
Yang Ke, Xie Guang-xiang, Chang Ju-cai, (2009). Study on the stability of rock surrounding gateway with different coal – pilar widths. Chinese Jounal of Underground Space and Engineering. Vol 5: 991-996.
Xia Jingchao, (2019). Research on the influence of repeated mining on Tunnel safety and Its control measure. North China University of Technology.
XU Zhu-he, XIAO Peng, LI Xiao-bin, (2020). Study on Control Technology of Roadway Affected by Mining in Extra Thick Coal Seam. Coal Technology. Vol.39 No.06: 8-11. Doi:10.13301/j.cnki.ct.2020.06.003