弓长岭露天矿含空区边坡稳定性研究

针对弓长岭露天铁矿含空区边坡稳定性问题，考虑不同大小、位置空区对边坡稳定的影响，利用FLAC和Geo-slope软件，分别模拟3种情况（包括36种情形）下边坡的稳定性：①不含空区；②空区分别位于边坡上部、中部、下部和坡角底部,这些空区距坡面的距离固定，改变空区的宽度；③空区大小确定，改变空区距坡面的距离。通过对比不同宽度、位置空区的边坡塑性区、位移云图和安全系数来分析空区对边坡稳定性的影响规律。结果表明：上部空区的存在有利于边坡整体稳定，但是影响边坡的局部稳定；中部空区的存在对边坡稳定性影响比较复杂，既有对边坡稳定有利的情况，也有对边坡稳定不利的情况；下部空区的存在严重影响边坡的稳定性。该规律对露天开采转地下开采很有借鉴意义。

Study on Stability of the Slope With Goafs in Gongchangling Open-pit Mine

For the stability of the slope with goafs in Gongchangling open-pit iron mine，the influence of goafs with different size and position was considered. Numerical simulation was carried out by FLAC and Geo-slope software. Three conditions (including 36 cases) of the slope stability were simulated: ①without goaf；②goaf lies in the top, middle, lower part and bottom of the slope and the distance of all goafs from slope surface is fixed, and the width of the goaf is changed；③The size of goafs is fixed, and the distance from slope is changed. Through contrasting with plastic zone，displacement and safety factor of slope with different goafs, the influence law of the goaf on the slope stability was obtained. The results showed that the goaf in the upper slope is beneficial to the overall slope stability，but has influence on the local stability of the slope. The goaf in the middle slope has more complex influence on slope stability，both favorable or unfavorable for slope stability situation. The goaf in the lower part of the slope has serious influence on slope stability. This law has reference meaning in transferring from open-pit mining to underground mining.