关键词: 沿空留巷, 充填墙体, 联合支护, 数值模拟

Abstract: Taking the gob-side entry retaining at the working face 3311 at Hexi coal mine as the back- ground and using FLAC3D finite difference program, this paper has calculated and analyzed the distribu- tion characteristics of stress and deformation in the gob-side entry retaining surrounding rock, filled wall and coal pillars, and proposed reasonable support methods for the gob-side entry retaining. The research results have shown that: the fierce degree of the vertical stress and horizontal stress change in the immediate roof is obviously bigger than that in the main roof for the gob-side entry retaining; the mechanical change of the surrounding rock and filled wall is obviously influenced by the hysteresis mining-induced stress after the mining of the working face 3311 and the main impact is on the vertical stress change; at the second mining phase of the working face 3313, the deformation of the roadway surrounding rock caused by the mining influence at this phase is much more sensitive to the influence of the stress, which means after the action of the second mining stress, while the stress in the filled wall and the roadway surrounding rock increases moderately, the roadway deformation increases relatively significantly and is mainly in the form of convergence of floor heave and ribs. The underground test has indicated that with the combined support of the bolt, cable bolt and filled wall and optimized onsite construction, gob-side entry retaining has met the ventilation requirement of the mining face, reduced the cost of the roadway exaction and realized the rapid advancement of the mining face.

Key words: gob-side entry retaining, filled wall, combined support, numerical simulation