main roof造句

• Analysis of the way for the main roof caving relating to the staggered sublevel caving method
  错层位放顶煤方法老顶垮落方式分析
• In accordance with the occurrence behavior of roof strata and the fracture characteristics of key stratum in shallow seam longwall mining , studied post - buckling behavior of roof key stratum in the process of mining by using initial post - buckling theory , which derived a critical load and a breaking span of the main roof during the first weighting , determined the final subsidence and the maximum rotation angle for broken key stratum , and presented an application with the example of daliuta 1203 face
  摘要根据浅埋煤层顶板岩层的赋存特点和长壁开采时关键层的变形破断特征，应用初始后屈曲理论探讨了开采过程中顶板关键层的后屈曲性态，得出了老顶初次来压时顶板的临界载荷和破断步距，确定了顶板破断后的极限下沉量和回转角，并以神东矿区大柳塔1203工作面为例给出了工程实例。
• Cross - check the main roof truss roof installation quality of the surface is not perpendicular to the vertical center two blocks ; roof surface pressure chord of the roof truss vertical bending side , we must ensure that such errors do not exceed the allowable deviation to ensure roof stability and comply with the design requirements of the state by force
  屋架安装质量主要检查屋架跨中对两支座中心竖向面的不垂直度;屋架受压弦杆对屋架竖向面的侧面弯曲,必须保证上述偏差不超过允许偏差,以保证屋架符合设计受力状态及整体稳定要求