大跨度采场上部硐室条形矿柱尺寸优化研究

Optimization of strip pillar size in upper chamber of long-span stope

为了保证大跨度采场上部硐室稳定和作业安全,研究上部硐室条形矿柱最优宽度尺寸。首先分析条形矿柱的力学承载机理,运用突变理论推导条柱失稳的必要条件,并初步确定上部硐室条柱宽度。随后对大跨度采场开挖及上部硐室稳定性进行数值模拟,得到不同宽度条形矿柱下上部硐室顶板和条形矿柱的位移变化、最大应力变化和塑性区。最后通过对模拟结果的综合研究,确定对于30 m宽的大跨度采场,上部硐室条形矿柱最优宽度为5 m。现场开挖情况表明:研究结果与现场实际情况相吻合,5 m宽度条形矿柱对于上部硐室具有良好的支撑作用,条柱所受破坏较小,有效保证了上部硐室的稳定和作业现场的安全。

In order to ensure the stability and operation safety of the upper chamber of the large-span stope,the optimal width of the strip pillars in the upper chamber has been studied.Firstly,the mechanics bearing mechanism of strip pillar has been analyzed,the necessary conditions for the instability of strip pillars have been deduced through catastrophe theory,and the width of strip pillars in upper chamber has been preliminarily determined.Subsequently,excavation of long-span stope and the stability of the upper chamber have been simulated numerically.The displacement,maximum stress,and plastic zone of upper chamber roof and strip pillar under strip pillar with different widths have been obtained.Finally,the comprehensive analysis of simulation results has shown that the optimum width of strip pillar in upper chamber is 5 m for a large-span stope with a width of 30 m.The field excavation has shown that the research results are consistent with actual situation,the 5 m-width strip pillar has a good supporting effect on the stability of the upper chamber,and the damage of the strip pillar was small,which effectively guarantees the stability of the upper chamber and the safety of the working site.