急倾斜煤层俯伪斜工作面基本顶破断特征分析

Main roof fracture characteristics of pitching oblique fully mechanized working face in steeply inclined coal seam

为深入研究急倾斜煤层俯伪斜综采工作面基本顶破断特征,以重庆逢春煤矿N2821综采工作面为例,利用薄板理论,同时考虑煤层倾角α和工作面俯采角度β对采场的影响,建立了急倾斜煤层俯伪斜工作面基本顶弹性薄板模型,得出了工作面基本顶的挠曲变形方程,并进一步分析了在两个角度共同影响下的俯伪斜综采工作面基本顶应力分布特征,经过理论计算得出了基本顶的初次来压步距为13.7 m,周期来压步距为7.9 m,揭示了急倾斜煤层俯伪综采工作面最大挠度点位于工作面的中部偏下端头位置处,基本顶初次破断和周期破断特征分别为“⊂-≻”型和“⊂-≻”型破断,研究结果为急倾斜工作面煤层顶板控制提供了一定的理论参考。

In order to further study the roof fracture mechanism of pitching oblique fully mechanized working face in steeply inclined coal seam,taking N2821 working face of Fengchun Coal Mine as an example,based on the plate theory,considering the influence of coal seam angleαand working face angleβon stope,a model of elastic thin plate of the main roof is established.The equation of roof deflection and deformation of subducted pseudo inclined working face is obtained.The stress distribution characteristics of the main roof of the pitching oblique fully mechanized working face under the influence of two angles are further analyzed.Moreover,the initial and periodic fracture distances of the main roof are theoretically calculated to be 13.7 m and 7.9 m,respectively.The maximum deflection point of the working face is located at the lower end of the middle part of the working face and the characteristics of“⊂-≻”type initial fracture and“⊂-≻”type periodic fracture of roof in steeply inclined coal seam are revealed.The research results can provide certain theoretical reference for the control of coal seam roof in steeply inclined working face.