powder charge

Using common powder charge structure makes larger vibration damage to the surrounding rock when drifting, and it needs higher requirements to tunnel support which leads to higher final cost.

巷道掘进过程中采用普通装药结构对围岩振动损伤较大，导致对巷道支护要求高，支护成本增大；

This cartridge has a powder charge of 50 grains.

这种子弹筒能装50发子弹.

The results of the calculation show that when the blasting with not-coincident powder charge is happened, the effective affecting radius of stress waves is about eight times of the diameter of the blasthole.

计算结果表明，采用不偶合装药的爆破方法时，应力波有效作用半径约为炮孔直径的8倍。

This makes it possible for theoretical powder charge length of a row or a tier boreholes to be further calculated complexly for wider use.

从而可进一步对一排（层）炮孔理论装药长度进行复合计算和更广泛使用。