软煤综放开切眼顶板锚固支护理论研究

Theoretic Study on Roof Anchor Support for Open-off Cut in Soft Coal Fully-mechanized Mining

为了研究软煤综放开切眼顶板锚固支护原理,采用数值模拟方法对已破碎顶板近似处理为似连续体,分别对一系列不同锚固体厚度进行模拟。经对其表面中点水平应力及垂直位移场分析后得出:当锚固体厚度小时(厚宽比<3/10),其内部的拉应力为顶板破坏的决定因素;当锚固体厚度大时(厚宽比≥3/10),其内部的剪应力为顶板破坏的决定因素。因此,通过力学理论分析和数值模拟计算,提出软煤综放开切眼顶板内形成的锚固体厚度与开切眼跨度比为3:10较为合理。

To study the roof anchor support for open-off cut in soft coal mechanized mining,the roofs which had been broken were processed as continuity in numerical simulation.A series of different anchor thicknesses were simulated.After the analysis of horizontal stress in the center of surface and vertical disposition field,the results were: when the thickness was small(width-thickness ratio < 3/10),the interior tensile stress was the decisive factor in roof destruction;when the thickness was large(width-thickness ratio >3/10),the interior shear stress was.Therefore,by the theoretical analysis and numerical simulation,the rational ratio between the anchor thickness and open-off cut width is 3/10.