JP2004211442A - Uniformly arranging tool of fixing wedge - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a uniformly arranging tool of a fixing wedge for preventing a deviation of additional stress applied to a PC steel material by gripping the PC steel material by arranging respective divided pieces of the wedge without dislocating in the peripheral direction or the shaft direction with a simple constitution. <P>SOLUTION: This uniformly arranging tool has a cylindrical part 10 fitted outside the PC steel material (a PC steel stranded wire 100) and a projection part 20 arranged in an end part of the cylindrical part 10, inserted between wedge divided pieces for gripping the PC steel material and uniformly arranging the respective divided pieces in the peripheral direction. When inserting the projection part 20 between the respective wedge divided pieces, the divided pieces can be arranged uniformly in the peripheral direction. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a jig for uniformly arranging divided pieces of a wedge for fixing an end portion of a PC steel material in a PC structure. In particular, the present invention relates to a jig capable of arranging wedge split pieces without shifting in a circumferential direction and an axial direction of a PC steel material.
[0002]
[Prior art]
A fixing device using a wedge is known as a structure for fixing a PC steel material such as a PC steel strand to a PC structure. As shown in FIG. 3, the fixing device includes a combination of a wedge 200 and an anchor disk 120 or a female cone 130 having tapered holes 121 and 131.
[0003]
The wedge 200 is generally formed into a truncated cone shape having a large diameter at one end and a small diameter at the other end by combining two or three divided pieces. When the divided pieces are combined, a circular hole extending in the axial direction is formed at the center of the wedge 200. The PC stranded wire 100 is gripped by the wedge 200 in this circular hole. Further, a groove is formed on the outer periphery of the large diameter side of each divided piece. In a state where the divided pieces are combined in a truncated cone shape, an O-ring (not shown) is fitted into this groove so that the divided pieces are bound so as not to be separated.
[0004]
The PC steel stranded wire 100 whose end is gripped by the wedge 200 is given a predetermined tension by a jack, and is fixed by fitting the wedge 200 into the tapered hole of the anchor disk 120 or the female cone 130. The anchor disc 120 or the female cone 130 is arranged on the anchor plate 110 located on the surface of the concrete structure, for example. Note that, instead of the anchor plate, a rib cast anchor or a socket may be used.
[0005]
By the way, in such a wedge, there is a problem that the divided pieces are unevenly arranged in the axial direction of the PC steel stranded wire and in some cases also in the circumferential direction. As described above, the conventional wedge merely retains a truncated conical shape by binding the divided pieces with an O-ring. For this reason, as shown in FIG. 4, the O-ring 140 easily extends at the time of fixing, and each divided piece may be shifted in the axial direction or the circumferential direction. For example, when the PC steel strand is bent near the fixing device (when not linearly arranged), it is difficult to uniformly dispose the divided pieces in the axial direction, and the applied stress applied to the PC steel strand also acts unevenly. May be. In particular, wedges used for diagonal cables and outer cables of cable-stayed bridges that require high fatigue characteristics require a high level of uniform arrangement of the divided pieces, and further prevention of slippage is required.
[0006]
On the other hand, a wedge driving device described in Patent Document 1 is known as a conventional technique for preventing such a displacement. This device includes an outer cylinder and a hollow extrusion cylinder slidably housed in the outer cylinder. The distal end of the outer cylinder has a leaf spring for temporarily fixing the divided pieces and a stopper located between the divided pieces to prevent the divided pieces from moving on the circumference.
[0007]
[Patent Document 1] Japanese Patent Application Laid-Open No. 7-279912
[Problems to be solved by the invention]
However, the technology described in Patent Document 1 has the following problem.
(1) The configuration of the wedge driving device is complicated.
A stopper and a leaf spring are required to keep the divided pieces combined in a truncated conical shape, so that the number of parts is large and the configuration of the apparatus is complicated.
[0009]
{Circle around (2)} When the wedge split pieces are bound by an O-ring, they cannot be used.
If the divided pieces are bound by an O-ring, the stopper disposed at the distal end of the outer cylinder expands the O-ring, so that the O-ring cannot bind the divided pieces. Further, when the wedge is pushed in by the pushing cylinder, the leaf spring interferes with the O-ring, which causes problems such as hindrance to pushing out the wedge smoothly and the O-ring falling off.
[0010]
Accordingly, a main object of the present invention is to provide a fixing wedge having a simple configuration, in which the divided pieces are arranged without being shifted in the circumferential direction or the axial direction to grip the PC steel material and to prevent bias of the applied stress applied to the PC steel material. An object of the present invention is to provide an evenly arranged jig.
[0011]
Another object of the present invention is to provide a fixing wedge that can be used without any problem even when the wedge division pieces are bound by an O-ring, and that can prevent the division pieces from shifting in the circumferential or axial direction. To provide tools.
[0012]
[Means for Solving the Problems]
The present invention achieves the above object by using a jig in which the divided pieces are evenly arranged when the wedge is inserted into the tapered hole.
[0013]
That is, the jig of the present invention is provided between the cylindrical portion fitted on the outer side of the PC steel material and the end of the cylindrical portion, and is inserted between the wedge divided pieces for gripping the PC steel material to surround each divided piece. And a protrusion arranged evenly in the direction.
[0014]
By using a jig having projections arranged evenly at the tip of the cylindrical portion, if this projection is inserted between the wedge split pieces, the split pieces are automatically and uniformly arranged in the circumferential direction. As a result, it is possible to eliminate the case where the PC steel material is gripped while the displacement occurs.
[0015]
The jig of the present invention has a cylindrical portion and a projection. The cylindrical portion has an inner diameter through which a PC steel material can be inserted. When the protrusion is inserted between the split pieces of the wedge, the material of the cylindrical portion hits the side of the cylindrical portion without the protrusion, so that the material has sufficient mechanical strength to withstand the impact Consist of things.
[0016]
In this cylindrical portion, it is preferable that the end face provided with the protrusion is formed of a surface orthogonal to the axial direction of the cylindrical portion so that the divided pieces can be evenly arranged in the axial direction. With this configuration, when the projecting portion is inserted between the divided pieces and the jig is driven into the wedge side, the end face of the cylindrical portion comes into contact with the large diameter side end face of the wedge, and each divided piece is shifted in the axial direction. It can be arranged without.
[0017]
On the other hand, the protrusions are a plurality of protrusions protruding from the end of the cylindrical portion. Each projection is evenly arranged in the circumferential direction of the cylindrical portion. Usually, each protruding portion is made of the same material as the tubular portion and is integrally formed. The number of projections is a number corresponding to the number of gaps between the divided pieces. For example, when a wedge is formed by three divided pieces, the number of gaps is three, and the number of protrusions is three.
[0018]
It is preferable that the shape of the protrusion is a tapered shape that becomes thinner toward the tip. By making the projections tapered, the projections can be easily inserted between the divided pieces and can be easily removed.
[0019]
The above jig is used by inserting a protrusion between the divided pieces constituting the wedge and hitting the end of the cylindrical portion opposite to the protrusion. By inserting the protrusion between the divided pieces, the divided pieces can be evenly arranged in the circumferential direction. Further, since the end face of the cylindrical portion provided with the projection abuts on each of the divided pieces, each of the divided pieces can be arranged without being shifted in the axial direction.
[0020]
In this jig, a projection may be inserted between the divided pieces in advance, and then the divided pieces may be inserted into a tapered hole such as a female cone, or the divided pieces may be inserted into a tapered hole such as a female cone. After that, a projection may be inserted between the divided pieces.
[0021]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described.
<Jig configuration>
FIG. 1 shows a jig of the present invention, in which (A) is an end view and (B) is a front view.
This jig has a cylindrical portion 10 and a protruding portion 20 protruding from one end thereof. The cylindrical portion 10 is a cylindrical member having an inner diameter into which a PC strand is inserted, and having an outer diameter slightly smaller than the outer diameter of the wedge. In this example, the cylindrical portion 10 was formed of a carbon steel pipe for machine structure (STKM13A) having an outer diameter of 25.4 mm and an inner diameter of 19.4 mm.
[0022]
A protrusion 20 is formed on one end of the tubular portion 10. In this example, the three protrusions 20 are evenly arranged in the circumferential direction at intervals of 120 °. The projecting portion 20 is also made of the same material as the tubular portion 10 and is integrated with the tubular portion 10.
[0023]
The protruding portion 20 has a tapered shape in which the width on the base side is wide and the width becomes narrower toward the tip side. Its length is 10 mm, the width on the root side is 4 mm, and the width on the tip side is 3 mm.
[0024]
One end of the cylindrical portion 10 where the protrusion 20 is formed, that is, a portion of the end surface of the cylindrical portion where the protrusion 20 is not provided is formed of a surface orthogonal to the axial direction of the cylindrical portion 10.
[0025]
<Jig use procedure>
This jig is used in the following procedure.
As a premise, as shown in FIGS. 3 and 4, a wedge 200 having one end on the large diameter side and the other end on the small diameter side is prepared. The wedge 200 is formed in a substantially truncated conical shape by combining three divided pieces. Such divided pieces are combined in a truncated cone shape, and an O-ring is fitted from the outer periphery so that the divided pieces do not fall apart.
[0026]
As shown in FIG. 2, the projection 20 of the jig is inserted into the gap between the divided pieces (wedges 200) in the combined state. Since the protruding portion 20 is formed in a tapered shape that is thinner toward the distal end, it can be easily inserted into the gap between the divided pieces. By inserting the jig into the gap, the projections 20 are evenly arranged in the circumferential direction of the cylindrical portion 10, so that the divided pieces are also equally arranged in the circumferential direction.
[0027]
Furthermore, when the protrusion 20 is inserted into the gap between the divided pieces, the surface of the cylindrical portion end face without the protrusion 20 comes into contact with the wedge large diameter side end face. Due to this contact, the divided pieces are arranged without being shifted in the axial direction.
[0028]
In this state, the wedge 200 combined with the jig is fitted into the female cone 130. As shown in FIG. 2 or FIG. 3 (B), the female cone 130 is configured such that a tapered hole 131 is formed, and the wire 100 from the PC steel projects from the tapered hole 131.
[0029]
The wedge 200 combined with the jig is inserted into the tapered hole 131 in a state where each divided piece is not displaced in either the circumferential direction or the axial direction. Does not occur.
[0030]
Then, the other end of the cylindrical portion 10, that is, the side having no protrusion is hit with a hammer or the like, and the wedge is pressed into the tapered hole 131. Thereafter, the jig is removed from the wedge 200.
[0031]
【The invention's effect】
As described above, according to the jig of the present invention, the following effects can be obtained.
[0032]
(1) By using a jig having projections arranged evenly at the tip of the cylindrical portion, if the projections are inserted between the wedge split pieces, the split pieces are automatically evenly distributed in the circumferential direction. Therefore, the problem that the PC steel material is gripped while the displacement occurs can be solved.
[0033]
{Circle over (2)} The jig of the present invention has a very simple structure in which a plurality of protrusions are formed at the end of the cylindrical portion, and a simple usage method in which the protrusions are inserted between the wedge split pieces. Thus, the displacement of the divided pieces can be suppressed. In particular, the jig of the present invention can be used without any problem even when the wedge division pieces are bound by an O-ring.
[0034]
{Circle around (3)} By making the shape of the projection tapered toward the tip, the projection can be easily inserted between the wedge split pieces and pulled out.
[0035]
{Circle around (4)} By configuring the end face of the tubular portion provided with the projections with a surface orthogonal to the axial direction of the tubular portion, the divided pieces can be evenly arranged in the axial direction.
[Brief description of the drawings]
FIG. 1A is an end view of the jig of the present invention, and FIG. 1B is a front view thereof.
FIG. 2 is an explanatory view showing a state where the jig of the present invention is fitted between wedge split pieces.
FIG. 3A is an explanatory diagram of a fixing structure using an anchor disk, and FIG. 3B is an explanatory diagram of a fixing structure using a female cone.
FIG. 4 is an explanatory diagram showing deviation of divided pieces constituting a wedge.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Cylindrical part 20 Projection part 100 PC steel strand 110 Anchor plate 120 Anchor disk 121 Tapered hole 130 Female cone 131 Tapered hole 140 O-ring 200 Wedge

Claims (3)

A tubular part fitted on the outside of the PC steel,
A fixing wedge provided at an end of the cylindrical portion and being inserted between wedge divided pieces for gripping the PC steel material, the projections being arranged evenly in the circumferential direction of the divided pieces. Jig evenly arranged. 2. The jig according to claim 1, wherein the projection has a tapered shape that becomes thinner toward the tip. The end face of the tubular portion provided with the protrusion is formed of a surface orthogonal to the axial direction of the tubular portion so that the divided pieces can be arranged evenly in the axial direction. 3. The jig for evenly disposing the fixing wedge according to 2.

Images