基于板壳理论的采空区顶板稳定性分析及应用

Analysis and Application of Roof Stability in Goaf Based on Plate and Shell Theory

金厂河铅锌铜多金属矿主采区矿石资源消耗过快,D采区为主要补给矿块,铅锌品位低,充填掘进工程量多,充填难度大、成本高。针对金厂河铅锌矿D采区现存问题,运用弹性理论建立板壳结构力学分析模型,研究采空区顶板经历两次冒落而趋于稳定,计算分析不同方案下的采空区顶板的初始冒落高度分别为11~38 m、26~58 m、41~87 m,后续稳定冒落高度可达1.5~2.0倍采空区跨度。同时,依据采场参数和松散体特性,分析冒落67~100 m即可自然挤压冒落拱底板。为防治地表错裂塌陷,提出及时废石充填空区挤压临时矿柱,增强矿柱支撑能力和限制空区大范围冒落。以此设计空场法、留矿柱空场法和空场适时充填不同开采方案,通过空区顶板初始冒落高度、矿柱承载数值、回收矿量对比,推荐空场适时充填方案可保证D采区安全开采。

Aiming at the existing problems in D mining area of Jinchanghe Lead-zinc Mine,which included excessive consumption in main mining area,low grade of lead and zinc,amount of excavation work,difficulty in filling and the high cost,the mechanical model of plate and shell structure was established by applying the theory of elasticity to reveal two caving sta-ges,analyse the initial falling height of goaf roof of 11~38 m,26~58 m and 41~87 m under different schemes,and calculate the following stable caving height reaching 1.5~2.0 times the span of goaf.At the same time,according to the stope parameters and the characteristics of loose body,it was analyzed that the falling arch floor can be naturally squeezed when falling 67~100 m.In order to prevent the surface dislocation collapse,it was proposed to squeeze the temporary pillars by waste rock filling in time strengthening the pillar support capacity and limiting the caving of the large area.Based on this,different mining schemes of open stope method,pillar retaining open stope method and open stope timely filling were designed.Through the comparison of initial caving height of goaf roof,pillar bearing value and recovered ore volume,the open stope timely filling scheme was recom-mended to ensure the safety of D mining area.