| 摘要 |
PROBLEM TO BE SOLVED: To provide a method and a member for protective execution of a wall with a rock bolt hole, allowing the reliability of a rock bolt anchoring function to be enhanced by enabling a rock bolt hole to be stably drilled into the ground having a surface layer part likely to crumble while preventing the collapse of the hole and enabling a grout material to be reliably injected. SOLUTION: A drilling rod 24, whose end is fitted with a bit 25, is covered with an outer pipe 26 and mounted on a drilling machine 20. The outer pipe 26 is mounted on the drilling machine 20 through an outer pipe entraining adapter 1 rotatably holding the outer pipe 26 to the drilling rod 24, and the hole is drilled by means of the drilling rod 24 while permitting the outer pipe 26 to be hauled in such a condition that the bit 25 protrudes from the end of the outer pipe 26 by a prescribed length.
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