| 摘要 |
PROBLEM TO BE SOLVED: To enhance working efficiency of a series of drilling operations including a setup for preventing a core from falling on a construction site, by greatly shortening time for the setup.SOLUTION: Before a through-hole TH is formed on a concrete floor CF, a bottom surface 33b of a fixture 33 is bonded to a drilling-scheduled location of the concrete floor CF in the state of butting against it, and a plurality of locking hook parts 27 of a hooking implement 25 are locked to a part-to-be-locked 35 of the fixture 33. |
