回采巷道顶板大深度切缝后煤柱应力分布特征

Distribution characteristics of coal pillar stress after the roadway roof being large depth cutting seam

以晋城煤业集团赵庄煤矿3305综采工作面工程地质条件和开采技术条件为背景,应用相似材料模拟和数值模拟方法,深入研究了回采巷道顶板切缝后不同切缝深度与回采巷道煤柱应力相关关系及应力分布特征。研究表明,与不切缝相比,回采巷道顶板切缝后,随切缝深度增加,垮落高度增加,以切缝高度处为垮落角顶点,顶板垮落角减小,垮落后矸石能够充满采空区并且支撑基本顶,减弱工作面采动应力传递,使煤柱应力降低。煤柱垂直应力峰值、垂直应力峰值位置距回采巷道煤壁距离和距工作面后方的距离与切缝深度成对数关系,煤柱垂直平均应力与切缝深度成非线性反比关系。

Similarity material simulation and numerical simulation were adopted to research on the relationship and stress distribution characteristics of roadway coal pillar stress with different depth cutting seam after cutting the roof in basis of engineering geological and exploitation technical conditions of the 3305 fully-mechanized face in Zhaozhuang Coal Mine.The conclusions show that the roof caving angle decreases with cutting seam height for the fulcrum,the height of breaking down increases with the increase of cutting seam depth,leading to the result that the gob is filled up and old roof is supported and the working face disturbance stress transmission is weakened and stress of the coal pillar is reduced comparing with no cutting seam of the roadway roof.Coal pillar vertical stress peak value,vertical stress peak value point away from the coal wall of roadway distance and the distance from the rear of working face follow by the cutting seam depth displays logarithmic relationship.The relationship between the average vertical stress of coal pillar and cutting seam depth is nonlinear inverse.