Roll pass on Angle steel rolling, I-beam rolling and U-section, etc. were intensively studied.
他对角钢孔型轧制的，工字钢轧制和U -型钢轧制等剧做过深入研究。
2
Forward support bolt combined with roop rock by bolting can play a roll of combined beam, which can prevent roof rock caving immediately after explosion.
超前支护锚杆锚固后与顶板岩石构成一体，这样使超前锚杆形成组合梁作用，放炮后，能够阻止顶板岩石冒落。
3
According to the results of model tests in a regular beam wave, the motion stability, the time history of the motion and the amplitude-frequency response of the parametric roll are investigated.