Research on small pillar remaining width and surrounding rock control technology in gob-side entry driving with hard roof
In order to study the surrounding rock stability control technology of roadway retaining with small pillar under the condition of hard roof,taking the practical engineering of large-height mining with hard roof in Shennanwa Coal Mine in Xiangning mining area as the background,the theoretical analysis,numerical simulation and field test methods were comprehensively used to study on the gob-side overburden structure,small pillar width and roadway surrounding rock stability.Based on the actual engineering background of gob-side entry driving with small pillar in 20108 working face in Shennanwa Coal Mine,the mechanical model of the gob-side overburden structure under the condition of hard roof was established,and the calculation formula of the length of the internal stress field under the condition of hard roof was derived,and then the theoretical width of the small pillar was determined as 7.27 m.Numerical simulation was used to compare and analyze key information such as stress,plastic zone distribution characteristics,displacement of the two sides and the roof and floor of the surrounding rock with different coal pillar widths.The optimal roadway retaining scheme was selected and industrial tests were conducted on site.Research had shown that using a 6-meter roadway pillar combined with a support method with high pre-tension anchor mesh cable,M-steel strip,and anchor beam,the maximum absolute displacement of the two sides during mining could be controlled within 520 mm with no occurrences of roof collapse,coal pillar collapse,or overall removal of anchor bolts in the roadway.
hard roofgob-side entry drivingsmall pillar widthsurrounding rock stability control
万方数据
维普
