TY - JOUR
T1 - Stability control of retained goaf-side gateroad under different roof conditions in deep underground Y type longwall mining
AU - Zhang, Zhiyi
AU - Shimada, Hideki
AU - Sasaoka, Takashi
AU - Hamanaka, Akihiro
N1 - Funding Information:
Acknowledgments: This research was sponsored by JSPS KAKENHI Grant Number 15H02332 and State Scholarship Fund from China Scholarship Council (CSC). We also thank Dalia Lahav-Jones, from Liwen Bianji, Edanz Group China for editing the English text of a draft of this manuscript.
Publisher Copyright:
© 2017 by the authors.
PY - 2017/9/21
Y1 - 2017/9/21
N2 - Abstract: Stability of the retained goaf-side gateroad (RGSG) is influenced mainly by the movements of the roof strata near coal seam after coalface passes by. To make effective controlling technology for the stability of the RGSG, we analyze the roof structure over the RGSG to illustrate the mechanism causing the RGSG instability under different roof conditions. We then examine the dynamic evolution of the deformation and abutment stress in the rock surrounding the RGSG during coal seam mining, using the FLAC3D numerical software to reveal the instability characteristics of the RGSG under different roof conditions. Next, corresponding stability controlling technologies for the RGSGs are proposed and tested in three typical deep underground coalmines. Results show that: sink and rotation of the roof cantilever over the RGSG impose severer influence on the stability of the RGSG. The RGSG suffers disturbances three times during the coal-seam mining, and the deformation and abutment stress in the rock surrounding the RGSG increase significantly when the main roof becomes thicker and the immediate roof becomes thinner. Staged support technology involving grout cable bolts has better controlling results of the RGSG stability than that composed of conventional rock bolts, when the RGSG is beneath weak immediate roof with large thickness. Roof structure optimizing technology involving pre-split technology can improve the stability of the RGSG effectively when the RGSG is covered by hard main roof with large thickness directly.
AB - Abstract: Stability of the retained goaf-side gateroad (RGSG) is influenced mainly by the movements of the roof strata near coal seam after coalface passes by. To make effective controlling technology for the stability of the RGSG, we analyze the roof structure over the RGSG to illustrate the mechanism causing the RGSG instability under different roof conditions. We then examine the dynamic evolution of the deformation and abutment stress in the rock surrounding the RGSG during coal seam mining, using the FLAC3D numerical software to reveal the instability characteristics of the RGSG under different roof conditions. Next, corresponding stability controlling technologies for the RGSGs are proposed and tested in three typical deep underground coalmines. Results show that: sink and rotation of the roof cantilever over the RGSG impose severer influence on the stability of the RGSG. The RGSG suffers disturbances three times during the coal-seam mining, and the deformation and abutment stress in the rock surrounding the RGSG increase significantly when the main roof becomes thicker and the immediate roof becomes thinner. Staged support technology involving grout cable bolts has better controlling results of the RGSG stability than that composed of conventional rock bolts, when the RGSG is beneath weak immediate roof with large thickness. Roof structure optimizing technology involving pre-split technology can improve the stability of the RGSG effectively when the RGSG is covered by hard main roof with large thickness directly.
UR - http://www.scopus.com/inward/record.url?scp=85029713708&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85029713708&partnerID=8YFLogxK
U2 - 10.3390/su9101671
DO - 10.3390/su9101671
M3 - Article
AN - SCOPUS:85029713708
SN - 2071-1050
VL - 9
JO - Sustainability (Switzerland)
JF - Sustainability (Switzerland)
IS - 10
M1 - 1671
ER -
