Development of Scientific Mining: a Case Study of Gob-Side Entry Retaining Technology in China
The gob-side entry retaining technology, one of the scientific mining technical system, can enhance coal recovery rate and reduce entry excavation quantity. However, only the effective entry-side support and the proper entry-in support could guarantee stability of the retaining entry undergoing mining influences of two working faces. In order to recover the section coal pillar between two working faces, the technology is applied in Qinxin coal mine. By using the high-water rapid hardening material as backfill material, the backfill pumps as transportation equipments of the material, the steel formwork and backfill bag as forming molds of the material, the entry-side support is of high support resistance, certain shrinkage, convenient construction. As for the entry-in support, the bolt support is designed to improve the bearing capacity and anti-deformation capacity of the surrounding rock, and the single hydraulic prop is adopted to reinforce roof support. The observation results show that the retaining entry keeps good performance. The case not only brings better economical benefit for Qinxin coal mine but also has referential significance for other coal mines.
Y. Xu et al., "Development of Scientific Mining: a Case Study of Gob-Side Entry Retaining Technology in China", Advanced Materials Research, Vols. 255-260, pp. 3786-3792, 2011