To relieve the tension of driving behind the mining coal, the gob-side entry retained stage was promoted at stable roof, and the strip pillar along strike was distributed at unstable roof in Jixi Coal-Mining Group Co. Ltd. In order to slow driving behind the mining coal as well as avoid damnifying coal resource, the gob-side entry retained with building mullocks was ever developed, but its headroom had been less than 50% of its initial section when the mining deepness arrived at 600—800m. Further more, to solve the underground pressure problem of the gob-side entry retained stage, the gob-side entry retaining with the local grooving top-caving method was also brought forward, but it wasn't applied at all because the roof collapse was accompanying with the movement of the hydraulic support in the easily falling roof. On the basis of transformation of the gob-side entry retained stage, the gob-side entry retained stage with anchor cable and building the waste rock wall is put forward in this paper, i.e. the mild roof is first supported by anchor cable, and then it is again supported by the waste rock wall, so that cause a part of roof stress transfer to bottom, thereby avoiding roof excessive stress concentration. Qiujia Mine production practice shows that the gob-side entry retained stage with the waste rock wall and anchor cable can economically and effectively control the underground- pressure in the easily falling roof, but due to the transfer of stress is bigger, need many times excavating the bottom to eliminate the harm of the bottom drum.
LI Junping;HAO Fukun;YU Huijun
. The Technology and Application of the Gob-side Entry Retaining with Building Mullocks and Anchor Cable in the Roof Liable to Collapse[J]. Science & Technology Review, 2012
, 30(9)
: 69
-72
.
DOI: 10.3981/j.issn.1000-7857.2012.09.009