Supporting of gob-side entries driving head-on adjacent advancing coal face with a reserved narrow pillar

摘要

On the basis of analyzing the special structure of surrounding rock of gob-side entries, a comparison between gob-side entries driving in stable coal body and driving head-on adjacent advancing coalface is made. The latter case is severely subject to the whole breaking process of lateral main roof strata, which will unavoidably lead to the separation of coal seam from the roof and collapse of the narrow coal pillar. Therefore, its supporting in active state of surrounding rock is completely different from that of the former case. So a new kind of pretensioned truss, which can ensure the safety of the roof and control the serious deformation of roadway as well, is presented with a successful engineering practice.