强导(含)水隐伏陷落柱底板突水机理研究

华北型煤田采场底板隐伏强导(含)水岩溶陷落柱突水以其隐蔽性强,突水速度快,水量大,破坏性强,危害严重的特点已成为影响煤矿安全生产的重大隐患.但是,受奥陶系灰岩承压水和采动应力耦合作用下的岩溶陷落柱突水机理、突水过程和突水力学规律的研究尚不够系统和完善.本文以陷落柱上覆岩层层状介质假设和剪切破坏理论方法为出发点,建立了不同水平截面形状类型的强导(含)水岩溶陷落柱突水力学模型,并确立了奥灰承压水与采动应力共同作用诱发强导(含)水陷落柱突水的临界条件,并提出了突水危险性系数对陷落柱突水危险性进行定性和定量的评价.理论推导和数值分析表明,奥灰承压水和采动应力耦合作用下的强导(含)水陷落柱突水与其水平截面形状、隔水层厚度、岩石物理性质有关.当采场环境确定后,陷落柱水平截面形状则是决定其突水的关键因素,而且陷落柱水平截面形状是圆形时最容易发生突水.

Water inrush mechanism research of strong conducting (water including) karstic collapse column

North China type coalfield karstic collapse column water inrush is the most serious potential issue for coalmine production safety, as the water inrush quantity is significantly huge and destructive. However, research on karstic collapse column water inrush mechanism, water inrush process and mechanical model of water inrush is still in its infancy. In this paper, based on heterogeneity assumption of the collapse column overburden layer and shear failure theory, we established a water inrush mechanical model of strong conducting (water including) karstic collapse column of different cross section types. Besides, the critical condition of strong conducting (water including) karstic collapse column water inrush, which is caused by Ordovician confined water stress and mining stress during mining process, was established. Meanwhile, the water inrush risk coefficient is proposed and utilized to evaluate the karstic collapse column stability of water inrush resistance. Theoretical derivations and numerical analysis indicate that strong conducting (water including) karstic collapse column water inrush is a complex processes related with the column cross section shape, critical thickness of water-resisting layer, and rock physical properties. The work in this paper indicates that column section shape is the key for water inrush under the same mining environment, and the circle section column is the most vulnerable section shape of column to water inrush.