JP3079231B2 - End fixing device for synthetic resin coated PC steel wire - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a synthetic resin-coated P
The present invention relates to an end fixing device when C steel wire is used as a tension member.

[0002]

2. Description of the Related Art Conventionally, in the construction of prestressed concrete and ground anchors, rust of tendon material has become a problem, and a synthetic resin layer has been applied to the surface to prevent rust.
C steel wire is being used. As the end fixing device for the PC steel wire, one having a structure shown in FIG. 4 is generally used.

[0003] This conventional apparatus comprises a concrete structure 1
A fixing head 3 for wedge fixing is supported on the surface of a support plate 2 provided in the fixing hole 3. The fixing head 3 has a fixing hole 5 through which a PC steel wire 4 is inserted. The fixing wedge 6 is inserted into the provided tapered hole 5a, the wedge 6 is bitten by the return force due to the release of the tension after the PC steel wire 4 is tensioned, and the fixing is performed by the PC steel wire gripping force at that time. ing.

For tensioning the PC steel wire 4, a center hole jack 7 is used to set the fixing head 3 at a predetermined position. Then, the ram chair 7a is supported on the surface side of the support plate 2, and the jack 7 is pulled. The PC steel wire 4 is gripped by the head 8 with the same wedge 9 as described above, the pulling head 8 is driven in the pull-out direction to tension the PC steel wire 4, and then the fixing is performed by the fixing head 3.

[0005]

In such a conventional end fixing device, it is necessary to peel off the synthetic resin coating 4a of the PC steel wire 4 to the vicinity of the fixing end in advance. This peeling
Assuming the length of elongation due to tension, it is necessary to peel off the necessary amount in advance according to the length, but if the peeling length is too long, a problem on rust prevention occurs, and conversely, it is too short However, there is a problem that the covering portion is fixed by the wedge and a defect in fixing strength occurs.

An object of the present invention is to provide an end fixing device for a synthetic resin-coated PC steel wire in which such a problem is solved and the synthetic resin of an appropriate length is always automatically peeled off. .

[0007]

SUMMARY OF THE INVENTION In order to solve the conventional problems as described above and to achieve the intended object, a feature of the present invention is to provide a synthetic resin coating layer on the outer surface of a single-stranded or stranded PC steel wire. Is used as a tensioning material, and the uncoated end of the tensioning material whose coating is removed is inserted through a fixing hole of a fixing head, and a fixing wedge is inserted into the fixing hole. In the end fixing device of the synthetic resin-coated PC steel wire which is prevented from coming off,
A ring-shaped coating stripper is fitted to the uncoated end of the PC steel wire.

[0008]

In the apparatus according to the present invention, the synthetic resin coating is peeled in advance to the position of the coating stripper in the non-tensioned state, and tension is applied in this state, whereby the length of movement of the end due to the elongation of the PC steel wire is increased. , The synthetic resin coating is peeled off by the coating peeling tool.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of the present invention will be described with reference to FIGS. The same parts as those in the above-described conventional technique are denoted by the same reference numerals, and the description thereof will be omitted.

In this apparatus, a coating stripper 10 is provided corresponding to each fixing hole 5 on the back surface of the fixing head 3. This coating stripper 10 is entirely formed of a steel material.
As shown in FIG. 2, the inner diameter of the ring is formed to be substantially equal to the outer diameter of the PC steel wire 4 from which the coating is removed.

The coating stripping tool 10 is fitted to a portion of each of the PC steel wires 4 from which the synthetic resin coating 4a has been stripped in advance, and the leading end thereof is inserted into the fixing hole 5 of the fixing head 3. The tip side of the PC steel wire 4 is tensioned by a jack 7 to apply tension. At this time, since the PC steel wire 4 is stretched,
Although the end moves in the tension direction, the coating stripper 10 contacts the back surface of the fixing head 4 and does not move during the movement, so that the synthetic resin coating on the outer surface of the PC steel wire 4 is applied to the coating stripper 10.
Stripped off by the inner edge of

In addition to the above, as the coating stripper 10, there can be used one in which mountain-shaped cutting blades 11, 11 are integrally formed on the surface as shown in FIG. The portions 11 and 11 are cut in the vertical direction, and are easily peeled. In addition, the form of the coating stripping tool 10 is PC
Various types other than those described above can be used as long as the synthetic resin coating is stripped by relative movement with the steel wire.

[0013]

As described above, the synthetic resin coating P of the present invention
In the end fixing device of the C steel wire, the back of the fixing head is provided with a coating stripping tool that removes the synthetic resin coating by the movement of the PC steel wire. The coating on the outer surface is automatically peeled off according to the moving length, so that the synthetic resin peeling length is always appropriate, rust prevention and fixing are properly performed, and
The operation is much simpler and more efficient than the conventional method of removing the synthetic resin coating.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a perspective view of an example of a coating stripper used in the present invention.

FIG. 3 is a cross-sectional view showing a peeled state by the coating peeling tool.

FIG. 4 is a perspective view of another example of the coating stripper used in the present invention.

FIG. 5 is a cross-sectional view of a conventional PC steel wire end fixing device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Concrete structure 2 Support plate 3 Fixing head 4 PC steel wire 4a Synthetic resin coating 5 Fixing hole 5a Tapered hole 6 Wedge 7 Jack 8 Pulling head 10 Coating peeling tool 11 Cutting blade

Claims (1)

(57) [Claims] 1. A synthetic resin-coated PC steel wire in which a synthetic resin coating layer is applied to the outer surface of a PC steel wire made of a single wire or a stranded wire is used as a tensioning material, and the end of the tensioning material is stripped. A synthetic resin coating P formed by passing an uncoated end portion through a fixing hole of a fixing head and holding the fixing hole with a fixing wedge in the fixing hole.
A synthetic resin-coated PC steel, wherein a ring-shaped coating stripper is fitted to the uncoated end of the PC steel wire at the back of the fixing head in the end fixing device for a C steel wire. Line end fuser.