The best stress state of the U-shaped steel support is that the back wall is filled and compacted to make it press evenly. When the pressure value of the surrounding rock applied to the U-shaped steel
Supporting of soft rock tunnel excavation has been one of the key technical problems which affects the further development of coal industry production and construction of our country .
The stress principle of U-shaped Steel Arch Support
1. The hydraulic support worker must be familiar with the performance, structure, principle and hydraulic control system of the hydraulic support, familiar with the basic operation and hydraulic knowl
