| 摘要 |
PROBLEM TO BE SOLVED: To provide a prestress introduction method for a concrete structure, which significantly improves the performance of an arrangement material.SOLUTION: A hollow PC steel bar 11 in which a male screw is formed by rolling on an outer peripheral surface and a female screw-like unevenness is formed on an inner peripheral surface is used. A pressure-stopping plate 13 is positioned by a moving pressure-receiving plate 25 and a loosening prevention nut 14 on a device base 20, a slice rod 24 is inserted in an insertion hole 17A on a stopper plate 17 of a PC steel bar unit 10, a jack 22 is operated to press a pressing plate, a cylindrical nut 15 is rotated to screw a stopper plate which comes into contact with the pressing plate to be held, and the PC steel bar unit is contracted. The PC steel bar unit is set in a hole on a concrete structure 30, and a concrete 31 is placed around the hole. The cylindrical nut, the stopper plate, the pressing plate, the loosening prevention nut, the pressure-stopping plate, and a reaction core grid are removed, and prestress is introduced to the concrete structure. A steel bar 19 is inserted in the hollow PC steel bar, and a concrete 32 is placed between the steel bar and the inner peripheral surface of the hollow PC steel bar.SELECTED DRAWING: Figure 8 |
