露-井联采下煤层倾角对边坡稳定性影响规律研究

随着我国煤矿井下支护技术和设备的快速发展,利用井工开采露天煤矿端帮呆滞煤技术也日渐完善,为了研究不同煤层倾角条件下,露-井联采叠加扰动对露天煤矿端帮边坡稳定性的变化规律,依据煤层赋存条件及开采方式将端帮边坡下煤层倾角分为水平、水平、顺倾、逆倾3种类型,采用理论推导分析井工开采对端帮边坡的破坏原理,根据安家岭露天煤矿的岩体力学参数建立数值模型,通过数值模拟方法从端帮边坡的高应力区分布、变形破坏程度和破坏范围3个方面进行研究,得出露天煤矿端帮相同开采工艺、不同煤层倾角条件下边坡稳定性变化规律。结果表明:煤层倾角越大,工作面两侧高应力区影响范围越大,合理控制开切眼位置与边坡面的距离,可避免井采高应力区对边坡稳定性的影响;端帮下煤层倾角越大,井工开采后边坡的破坏范围越大;煤层为顺倾赋存状态时的对边坡的破坏程度大于水平赋存状态,而逆倾赋存状态破坏程度小于水平赋存状态;端帮下煤层顺倾状态不利于边坡稳定,煤层逆倾状态有利于边坡稳定。

Study on influence law of coal seam angle to slope stability under joint of open casting mining and underground mining

With the rapid development of underground coal mine support technology and equipment in China,the technology for mining open-pit coal at the end of open-pit mines using underground technology has also been gradually improved.In order to study the change law of the surface-underground combined mining disturbance on the stability of open-pit side slopes under different coal seam occurrence conditions,the coal seam occurrences under the side slope was divided into different levels according to the coal seam occurrence conditions and mining methods.Three types of sloping and backward tilting were used to theoretically analyze the failure principle of the sideslope sloping of the underground mining.A numerical model was established according to the rock mass mechanical parameters of the Anjialing Open-Pit Mine.The distribution of the high stress area,the degree of deformation and damage,and the scope of the damage were studied,and the law of slope stability changes under the same mining technology and different coal seam inclination in the open pit mine was obtained.The results show that the larger the dip angle of the coal seam,the larger the influence range of the high stress area on both sides of the working face,and the reasonable control of the distance between the open cut position and the slope surface can avoid the influence of the high stress areas on the slope stability;the greater the dip angle of the lower coal seam,the larger the scope of the slope damage after underground mining;when the coal seam is in the state of sloping occurrence,the degree of damage to the slope is greater than that in the horizontal occurrence,and the degree of damage in the state of anti-dip occurrence is less than the horizontal occurrence,the state of coal seam sloping under the end is not conducive to slope stability,and the state of coal seam sloping is favorable to slope stability.