大倾角大采高综采工作面支架受载与失稳特征分析

对支架的稳定性控制是大倾角大采高煤层安全、高效开采亟待解决的关键问题之一，以2130煤矿25221大倾角大采高综采工作面为研究背景，基于现场监测对覆岩破断运移规律和支架受载特征分析的基础上，通过理论分析系统研究了采高和工作面顶板运移对支架受载与失稳特征的影响。结果表明，在大倾角大采高煤层开采中，受采高增大影响，顶板运移的幅度和剧烈程度及支架工作阻力均较一般采高大倾角煤层开采时明显增大，架间推压、咬挤现象明显;当工作面顶底板岩层稳定时，使支架保持不转动和下滑的临界工作阻力均不超过支架自重的2倍;但受工作面顶板运移影响，支架亦会随着顶板的运动而运动，且其不会随着支架工作阻力的增大而消失;支架转动下滑的幅度和失稳概率随着支架工作阻力的减小、顶板与支架间摩擦力绝对值的增大、顶板载荷偏载程度的增大及采高的增大而增大，且其转动失稳的概率大于下滑失稳的概率。

Load and instability characteristics of support in large mining height fully-mechanized face in steeply dipping seam

The stability control of support is a technical problem to be solved urgently in steeply dipping thick seam mining.Based on the geological conditions and characteristics of strata behaviors of No.25221 working face in 2130 Coal Mine,China,the overburden migration law and load characteristics of support is analyzed with field monitoring,and the theoretical analysis is used to research the influence of mining height and roof movement on the load and instability of supports.Results show that the movement amplitude and intensity of the roof and working resistance of support are higher than those of normal mining height face in steeply dipping seam,which is due to mining height increase.When the roof and floor of working face is stable,the critical working resistance of support is less than two times the weight of support.However,with the influence of roof movement,the support will also move with the movement of the roof,which would not disappear with the increase of the working resistance of support.The movement amplitude and instability probability of the support are increased with the decrease of the working resistance of support and the increase of the friction between the roof and the support,the partial loading degree of roof load and mining height.In addition,the probability of rotation instability in large mining height fully-mechanized face in steeply dipping seam is greater than that of falling instability,and this phenomenon will be obvious with the increase of mining height.