advanced abutment pressure的用法和样例：
- It is elaborated that the abutment pressure has the process of formation and development,by which the behavior mechanism is explained.
- Overlength isolated working face reduces the superposed influence of two sides abutment pressure on isolated working face.
- It is put forward that the top coal of low gaseous steep seam can be caved only when the top coal is in the limiting equilibrium state of stress under the abutment pressure.
- Stress shell, which bears and pass load of overlying strata, is primary supporting body.The stress in skewback of stress shell forms abutment pressure of surrounding rock in vicinity of working face.