The roof control design in mined field is the key to roof control and the movement rule of roof terrane is the basis of the roof control design.

 
  • 采場(chǎng)控頂設計是頂板管理的關(guān)鍵因素,而頂板巖層的運動(dòng)規律是采場(chǎng)控頂設計的依據。
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