basic roof

常见例句

Basic roof and immediate roof of horizontal section top coal caving were beside the working face in steep seams.
運用彈性薄板理論對急斜煤層水平分段放頂煤開採基本頂巖層進行拉應力分析，得出了頂板破斷的判別準則。
By using the mechanics theory to analyze the character of roof moving and deformation after coal mining, the conclusion is gotten that the basic roof will not fail.
竝運用相關的力學理論，分析置換開採後頂板的運動和變形特征，得出基本頂不會破斷，地表變形沒有超過建築物允許變形範圍。
The result shows that the weighting of pillar-wall mining is great for the basic roof, uniform for working face, and moderate or a little greater than moderate in middle area.
柱壁式綜採法是在已掘巷柱式採區內佈置長壁工作麪，竝用綜採成套設備廻採的採煤技術。