This paper introduced the experience of the inverted plumb line boring with high vertical requirement at high angle of tilt and adamant rock, and the bore hole surveying straightening and installing of the plumb line.
英
美
- 介绍了在高硬度高倾角岩层施钻铅垂度要求很高的倒锤钻的经验及钻孔纤偏检查和安装倒锤线的方法。