| 摘要 |
This invention provides a measuring nail which can be prevented from being pulled out from a roadbed even when pushed down on the roadbed by a motorized grader, a macadam roller, a tired roller, a tire of a dump car carrying a pavement material or a foot of a worker, to provide an improved working efficiency. The measuring nail of this invention comprises a nail body embedded in a roadbed and a rod-like elastic member engageable with a top end of said nail body.
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