The underhand slice stoping method, with reinforced concrete for roof support, is recommended to mine narrow veins where the mining technological conditions are very complicated.

 
  • 針對采礦技術(shù)條件復雜的薄礦脈開(kāi)采,推薦采用有鋼筋混凝土護頂的下向分層充填采礦法。
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