回撤通道直接顶下沉量计算及其影响因素分析

Calculation of direct roof subsidence of retracement channel and analysis of its influencing factors

  • 摘要: 回撤通道的直接顶下沉量对设备回撤具有重要影响,本文基于基本顶断裂位置,建立了工作面贯通后回撤通道直接顶挠度力学模型,将支承应力表达式简化为与其拟合的xn次抛物线函数,断裂位置不同,n的取值不同,推导出了回撤通道顶板中心线处直接顶下沉量表达式。312工作面基本顶断裂位置d约12 m,此时n取4,求得直接顶下沉量约为105 mm。在理论计算的基础上,对直接顶下沉量影响因素进行了分析,结果表明:直接顶下沉量随着基本顶断裂位置、煤层埋深、应力集中系数及回撤通道跨度的增大而增加,随着直接顶厚度及弹性模量的增大而减小,其余因素影响较弱。在保证设备回撤空间的条件下,尽可能减小回撤通道跨度,控制直接顶下沉量。

     

    Abstract: The direct roof subsidence of retracement channel is of utmost importanie to the withdrawal of equipment in the final mining stage.Based on the basic roof fracture position, a mechanical model of the direct roof deflection of the withdrawal channel after penetration was established.The expression of the supporting stress was simplified to the n-th parabolic function of x fitted to it.The value of n varies with the fracture position, the expression of the direct roof subsidence at the center line of the roof of the retreat channel was derived.The basic roof fracture position d of 312 working face was about 12 m, at this time n was taken as 4, and the direct roof subsidence was about 105 mm.On the basis of theoretical calculations, the factors affecting the direct roof subsidence were analyzed.The results showed: The direct roof subsidence increases with the increase of the basic roof fracture location, coal seam depth, stress concentration coefficient and the span of the retreat channel, and decreases with the increase of the direct roof thickness and elastic modulus.The influence of other factors is not significant.Under the condition of ensuring the equipment withdrawal space, the span of the withdrawal channel should be reduced as much as possible to control the direct subsidence of the withdrawal channel.

     

/

返回文章
返回