浅埋煤层开采顶板切落条件下支架动载效应

发布时间：2018-12-13 20:55

【摘要】：针对浅埋煤层开采周期来压过程中顶板沿煤壁切落时对支架造成冲击的现象,根据基本顶回转切落造成直接顶岩体非线性破坏特征,建立了由基本顶-直接顶-支架-采空区矸石组成的力学模型,应用突变理论和岩石动力学方法,推导了直接顶失稳前后基本顶切落荷载作用下的支架压缩量表达式,分析了顶板切落过程中的动载效应,获得了顶板切落条件下支架工作阻力。研究结果表明:基本顶回转切落和直接顶失稳破坏是造成支架冲击的主因,直接顶岩体变形的突变量决定了冲击荷载的大小,系统失稳时的支架荷载除了与基本顶的周期来压步距、上覆岩层荷载、直接顶厚度有关外,还与支架和直接顶岩体的刚度比、直接顶岩体性质等因素相关。
[Abstract]:In view of the phenomenon of roof impact on the support during the mining period of shallow coal seam, according to the nonlinear failure characteristics of the direct roof rock mass caused by the basic roof rotary cutting, A mechanical model consisting of basic top, direct top, support and goaf gangue is established. By using catastrophe theory and rock dynamics method, the expression of support compression under the action of basic top shear load before and after direct top instability is derived. The dynamic load effect in the process of roof cutting is analyzed, and the working resistance of the support is obtained under the condition of roof cutting. The results show that the main causes of the impact are the basic roof rotary cutting and the direct roof instability, and the sudden change of the deformation of the direct roof rock mass determines the magnitude of the impact load. When the system is unstable, the support load is related not only to the periodic pressure step of the basic roof, the overburden load and the direct roof thickness, but also to the stiffness ratio of the support and the direct roof rock mass, and the properties of the direct roof rock mass.
【作者单位】：中国矿业大学(北京)力学与建筑工程学院;
【基金】：国家重点基础研究发展计划(973)资助项目(2013CB227903) 国家自然科学煤炭联合基金重点资助项目(U1361209)
【分类号】：TD323;TD355

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