Part roof fall accident cause is analyzed in flase top mining in No.5 Coal Seam of Pinggang Coal Mine.The prevention and cure measures are pointed out.

 
  • 通过对平岗煤矿5%23煤在托伪顶回采时发生的局部冒顶事故原因的分析,提出了解决该问题的防治措施。
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