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.

• 应用弹塑性理论分析了矿山压力对急倾斜煤层顶煤破碎的作用,认为在低瓦斯急倾斜煤层中只有当顶煤在支承压力的作用下进入应力极限平衡状态时,顶煤才可放出,据此计算顶煤可能的分段高度。