The crown pillar of stope is permanent loss and not recoverable, while sill pillar and barrier pillar shall be recovered after the ore drawing work is completed.
采场的顶柱作为永久矿柱损失，采场底柱、间柱等采场大量放矿完毕后，一次性进行回收。
2
The cause of mine pillar destruction in in Dachang Tongkeng Tin Mine was analyzed from observation by photoelastic stressmeter embedded in mine stope 570.
通过对埋设于570中段光弹性应力计的观测，分析了该中段矿柱破坏的情况及原因。
3
The technology and practice of artifical pumpcrete pillar support is briefly introduced in this paper. The mining test was carried out using the pillars, at 2364 stope of Woxi mining district.