综放工作面大跨距切眼支护技术研究

Study on Support Technology with Large-span Open-off Cut at Fully-mechanized Caving Face

针对庞庞塔矿9-301工作面开切眼掘进过程中,由于跨距大导致的支护难题,采用理论分析、数值模拟和现场试验等方法对大跨距切眼的破坏特征及控制技术进行研究。结果表明:顶板临界应力与切眼跨距a的二次方成反比关系,与顶板厚度h的二次方成正比关系;顶板塑性区深度与面积随切眼宽度的增加明显增大,两帮塑性区变化不明显。结合庞庞塔矿实际地质生产条件,设计采用锚网索联合支护技术,现场试验取得较好的控制效果。

In view of the support problems caused by the large-span open off cut at 9-301 working face of Pangpangta Colliery,the failure characteristics and control technology of the large span open-off cut are studied by theoretical analysis,numerical simulation and field test,whose results show that the critical stress of the roof is inversely proportional to the square of the cut span,and is proportional to the square of the roof thickness;the depth and area of the plastic zone of the roof increase significantly with the increase of the cut width,while the plastic zone of the two sides does not change obviously.Combined with the actual geological production conditions,the bolt-mesh-cable combined support technology is designed,and good control effect is achieved in the field test.