分段空场崩落采矿法顶板稳定性分析

蜂子山铅锌矿ⅪV1主矿体上下盘围岩均不稳固,试验应用改进的分段空场崩落采矿法。采用三维有限元对其护顶矿层和隔离矿柱的稳定性进行模拟分析。通过比较4种方案的应力、安全率和塑性区分布,优选了合理的采场结构参数。研究结果表明:矿房回采时,护顶层厚度对顶板稳定性有显著影响,顶板稳定性随护顶层厚度增加而提高;采场跨度对顶板稳定性也有较大影响,随采场跨度增加而降低。选取适当的护顶层厚度和控制采场跨度可有效保证空场稳定性,论文研究成果可为实际采矿设计和岩层控制提供理论依据。

Roof Stability Analysis of Sublevel Open Stope and Caving Mining Method

The hanging wall and footwall of the ⅪV1 main ore body are unstable in Fengzishan lead-zinc deposit.The improved sublevel open stope and caving method was tested.Using three-di-mensional finite element,the stability analysis of protective pillar and insulating pillar was presented.The distribution of stress,safety rate and plastic zone was analyzed,and the reasonable stope structural parameters were optimized in the four schemes.The results indicate that the thickness of protective layer has a significant influence on the roof stability,which improves with the increase of stope span during the room stoping.In addition,the roof stability decreases with the increase of stope span.It can effectively ensure the stope stability to select the suitable protective layer thickness and to control the stope span.The results can provide theoretical basis for the mining design and strata control.