1) tunnel enlarging
扩巷
1.
When blasting doesn t work, the high efficiency and noiseless breaking substance can be used in tunnel enlarging and basement excavation, and it is worthy of being popularized and applied.
本文介绍了在无法使用爆破法施工时,采用高效无声破碎剂扩巷和开挖基础的新技术,具有较高的推广应用价值。
2) side expansion
二次扩巷
补充资料：充扩
1.扩充，开拓。
说明：补充资料仅用于学习参考，请勿用于其它任何用途。