大红山铜矿矿柱的稳定性与岩体强度

Pillar stability and strength of rockmass of Dahongshan copper mine

对影响大红山铜矿矿柱稳定性主要原因进行了分析。发现影响矿柱稳定性的主要因素是充填欠账导致岩体强度的下降,以及断层等软弱结构面的存在。根据少量矿柱垮塌的情况和岩石试块力学试验结果得出,未垮塌地段岩体的单轴抗压强度在40MPa以上。在岩体强度较高的矿体东部,当矿柱高度较低时,可以将原设计8m的矿柱厚度降低为5m,以提高资源回收率。

Analyzing was performed for the reason of influencing the stability condition of the pillars of Dahongshan copper mine. It is found that the main factors influencing pillar stability are the descending of the rock strength caused by the lag of the backfilling, and the existance of the planes of weaknesses. It is concluded from some failed pillars and test results of rock samples that the un-axial compressive strength of the rock mass （unfailure pillar） is over 40MPa; and the pillar thickness could reduce from 8m to 5m for short pillars at east part of the ore body where rock is relatively stable.