roof break

Actual example analysis indicate that the roof motion over the working face take on typical chaotic character, its chaotic degree along the direction of the working face length is closely related to the roof break law and its structure feature.

实例分析表明：综放工作面覆岩运动呈现出典型的混沌性态，沿工作面长度方向上的混沌程度与顶板破断规律及结构特征密切相关。

You'll break your neck if you fall off the roof.

你要是从屋顶上跌下来会摔死的.

If you fall off that roof you will break your neck.

你要是从房顶上摔下来,你会摔死.

Based on the damage mechanics, the model of damage base beam is established and the movement of main roof and abutment influenced by break of main roof ahead of workface are analyzed.

基于损伤力学的思想，建立了损伤基础梁的力学模型，并用该模型的结论分析了老顶岩梁超前破断对支承压力及其运动状态的影响。

But they have never thought of the following scene: the chimney at the top of the kitchen might break, the fire might leap up to the roof and the burning purling might destroy their nests.

它们完全没有考虑到：炉灶上的烟囱有可能会炸裂，火苗将会窜上屋梁，烧着的椽将会摧毁它们的巢穴。