A new technique, supporting funnel method, is introduced to recover and controll large-scale collapse in main shaft.

介绍一种治理主溜井特大塌方的新方法——托斗法。

youdao

A new technique, supporting funnel method, is introduced to recover and controll large-scale collapse in main shaft.

介绍一种治理主溜井特大塌方的新方法——托斗法。

youdao