厚煤层预采顶分层综放工作面区段煤柱合理宽度留设研究

针对厚煤层预采顶分层综放工作面区段煤柱合理宽度留设的问题,以山东金桥煤矿1308工作面为工程背景,运用理论分析、公式计算、数值模拟的方法研究了煤柱的合理宽度范围、应力分布规律、塑性区分布特征,从而确定合理宽度值。研究表明:为确保煤柱中部没有过高应力叠加现象,煤柱宽度应大于21.9 m;煤柱宽度在14~22 m之间时,中部逐渐形成弹性区,两侧采空区在煤柱中应力叠加较强,应力峰值较高,煤柱的稳定性较差;煤柱宽度在22~32 m之间时,煤柱中部有足够弹性区宽度,两侧采空区的应力在煤柱上叠加程度较弱,稳定性高。因此,合理的区段煤柱宽度是22 m。

Study on Reasonable Width of Coal Pillars in Pre-mining Top-slicing Fully Mechanized Top-coal Caving Face of Thick Coal Seam

Aiming at the problem of reasonable width of coal pillars in thick seam pre-mining roof slicing fully mechanized mining face, taking 1308 working face of a mine as engineering background, the reasonable width range, stress distribution law and plastic zone distribution characteristics of coal pillars are studied by theoretical analysis, formula calculation and numerical simulation, so as to determine the reasonable width value. Research shows: to ensure that there is no overlapping phenomenon of excessive stress in the middle of the coal pillar, the width of the coal pillar should be greater than 21.9 m. When the width of the coal pillar is between 14 m and 22 m, the elastic zone gradually forms in the middle of the coal pillar. The stress overlap of the two sides of the goaf is stronger, the peak stress is higher, and the stability of the coal pillar is worse. When the width of the coal pillar is between 22 m and 32 m, there is enough elastic zone width in the middle of the coal pillar, and the stress in the goaf on both sides is weak and stable. Therefore, the reasonable width of coal pillar is 22 m.