特厚煤层大采高综放开采矿压规律

Research on strata behavior rules of ultra-thick seam in fully mechanized caving face with large mining height

为了对特厚煤层大采高综放开采矿压规律进行深入研究,以某煤矿15 m特厚煤层为实例,结合离散元法数值模拟和现场实测的方法对首采工作面矿压规律进行研究。现场实测结果表明,基本顶呈现周期性破断,周期来压步距在15~23 m范围内变化,且倾向方向工作面周期来压步距基本一致,来压期间动载系数不大。数值模拟结果表明,特厚煤层大采高综放开采过程中,基本顶中形成稳定的砌体梁结构,解释了开采过程中矿压显现不明显且来压期间无明显冲击载荷的现象。研究表明,该煤矿特厚煤层大采高综放开采工作面来压周期性比较明显,呈现高频率、低强度的特征,工作面液压支架满足安全生产要求,超前支护50 m较为合理。

Based on the example of 15 m ultra-thick coal seam in a certain mine,this paper studied the mining pressure rules of ultra-thick seam in fully mechanized caving face with large mining height.Numerical simulation of discrete element and field observation were conducted to study the mining pressure of first working face.The field test results indicated that the basic roof had periodic breakage and the periodic weighting distance varied from 15 m to 23 m.The pace of periodic weighting was generally consistent in trend direction and the dynamic load coefficient was basically invariable.The numerical results showed that the stable bond-beam structure was laid in basic roof which explained the phenomena of unapparent mining pressure and impulse load during the period of the pressure change.Research showed that the periodic weighting was obvious,which was characterized by high-frequency and low-intensity;hydraulic support in working face met safety production requirements and 50 m advanced support was relatively reasonable.