地下开采转露天复采复杂采空区顶板厚度的研究

为研究地下采空区顶板厚度对后期露天开采的影响,以紫金山金铜矿地下开采转露天复采为研究背景,运用5种经典理论计算公式对单一采空区顶板厚度进行计算,得出了顶板厚度的优化值; 并结合FLAC^3D有限元软件分析了多个采空区相连时所需的顶板安全厚度,提出了最优的采空区矿房跨度取值。结果表明,采矿量相同时,采空区矿房跨度越小,顶板越稳定,最小安全顶板厚度越薄; 为提高开采效率及安全等级,可适当减小采空区的矿房跨度。

Roof Thickness of Complex Goaf in Transition from Underground to Open-Pit Mining

In order to study the influence of roof thickness of underground goaf on subsequent open-pit mining, Zijinshan Gold Copper Mine in the transition from underground to open-pit mining was taken for analysis. Five classical theoretical calculation formulas were used to calculate the roof thickness of a single goaf, and then an optimal roof thickness was determined for the mine. The safety thickness of roof for several connected goaf rooms was also analyzed by using FLAC^3D finite element software, and then an optimal span of a goaf room was also determined. The results show that with the same mining quantities, a goaf with a shorter span of the roof will be more stable, and also the required minimum thickness of the safe roof will be lesser. Therefore, in order to improve mining efficiency and safety, the span of goaf can be appropriately shortened.