According to the number of practical data coming from drills and mines, the author puts forward classification of broken coal.

本文以陕西韩城矿区北区钻孔和井下大量的实际观测资料为依据，提出了破坏煤分类的方案。

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This paper discusses the classification of the stages of engineering geological works at coal mines and the assignments of the works in these stages.

本文论述了煤炭矿山工程地质工作的阶段划分及各阶段工程地质工作的任务。

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Also this paper discusses the classification of the designed structure model of underground mines.

论文对地下矿山构建筑物模型进行分类研究。

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