The article discusses feasibility of secondary mining of natural–manmade sylvinite seam KrII* in the Upper Kama Potassium Salt Field. The full scale tests of large samples were carried out to determine mechanical properties of seam KrII*. Mathematical modeling provides estimates of load exerted on nonuniform safety pillars after secondary mining. The authors propose alternative flow charts for the secondary mining of natural–manmade seam KrII* to ensure safety and reasonable efficiency of production.

中文翻译：

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钾储量二次开采的理由

本文讨论了在上卡马钾盐田二次开采天然-人造钾盐矿层 KrII* 的可行性。进行了大样本的全尺寸测试以确定接缝 KrII* 的机械性能。数学建模提供了二次开采后施加在非均匀安全支柱上的负载估计值。作者提出了天然-人造煤层 KrII* 二次开采的替代流程图，以确保安全和合理的生产效率。