JPH061765Y2 - Post-tension type pressure bearing plate mounting device in formwork for prestressed concrete member manufacturing - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a post-tensioning prestressed concrete member, for example, a post-tensioning prestressed concrete sleeper, a prestressed concrete track slab, a decimated PC plate, a prestressed concrete building member. Also, the present invention relates to a bearing plate attachment device for a manufacturing frame such as a slab of a general bridge.

[Conventional technology]

As shown in FIG. 10, the inventors of the present invention formed a dowel plate 7 at one end in the longitudinal direction of a formwork for manufacturing concrete sleepers, formed a bolt insertion hole 10 at the center thereof, and provided a draft on the outer peripheral surface thereof. 9 is projected, and two PC steel material insertion holes 13a,
The PC steel material insertion hole of the pressure bearing plate 3 in which 13b and the screw hole 14 located between the two PC steel material insertion holes 13a and 13b are formed.
Insert the fixed end sides of the PC steel materials 2 into 13a and 13b, respectively, and screw the tip ends of the bolts 16 inserted into the bolt insertion holes 10 of the dowel 9 into the screw holes 14 from the outside. Has been developed, and the device has already been filed as Japanese Patent Application No. 63-19251. 17 in the figure ...
Is a device for attaching the bearing plate 4 on the tensioned end side of the PC steel materials 2 to the end plate 8.

The pressure plate attaching device is a bolt for screwing the pressure plate 3.
Since the dowel 9 is fitted around the periphery of the dowel 16, a conventionally known device, that is, a bearing plate is supported on the end plate through a bolt screwed to the center thereof, and a plurality of dowels projecting from the end plate. PC inserted into the PC steel material insertion holes on both ends of the bearing plate
After demolding, compared to a device of the type that externally fits to the fixed end of steel material (large diameter head or nut screwed to the end of PC steel material) and positions the pressure plate (positioning of PC steel material) The number of dowel holes formed on the end surface of the concrete sleeper is reduced, and the work of filling the dowel holes is simplified, and the dowel holes are formed between the PC steel materials, that is, at a position away from the PC steel material. It has excellent advantages such as prevention of adverse effects on PC steel materials due to cracks in the parts and poor adhesion between the filled part and the first concrete part.

[Problems to be solved by the device]

However, the above-mentioned pressure bearing plate mounting device proposed as Japanese Patent Application No. 63-19251 has room for improvement in the following points.

That is, if the central portion of each pressure support plate 3 is simply screwed to the bolt 16, the pressure support plate 3 fixes the bolt 16 to the bolt 16 by the vibration applied to the concrete by the vibrator when the concrete is placed in the formwork. It may rotate around the center. In addition, one concrete sleeper is usually provided with two of the pressure bearing plates 3 described above, and two pressure bearing plates 3 are provided in total, for a total of four Ps.
C steel material 2 ... Is buried, but these bearing plates 3
When is rotated around the bolt 16, the positional relationship between the PC steel materials 2 ... Distorts, and even if the other end side of the PC steel materials 2 ... is pulled to introduce prestress to the concrete sleepers, the prestress distribution state as designed May not be obtained.

Therefore, as shown in FIGS. 11 and 12, a rotation preventing tool 18 having recessed portions 18a and 18b corresponding to the outer shapes of the pressure bearing plates 3 and 3 is provided on the upper portion of the groove-shaped mold body 6. Then, the concave portions 18a and 18b of the rotation preventing tool 18 are fitted to the pressure support plates 3 and 3 to prevent the pressure support plates 3 and 3 from rotating.
In this case, after placing the concrete, the rotation prevention tool
It is necessary to re-vibrate and fill the vertical hole formed by removing 18 with concrete.

An object of the present invention is to provide a bearing plate mounting device improved in the above points.

[Means for Solving the Problems]

The technical means taken by the present invention to achieve the above object are as follows. That is, according to the present invention, a bolt insertion hole is formed in the center of the end plate of the PC steel material in the post-tensioning prestressed concrete member manufacturing form, and the outer peripheral surface is drafted, and the tip surface is Is a plurality of PC steel material insertion holes, screw holes located between these PC steel material insertion holes, and recesses or projections corresponding to the projections or recesses. P in the PC steel material insertion holes of the bearing plate on which
The fixed end side of the C steel material is inserted, and the tip end of the bolt inserted into the bolt insertion hole of the dowel from the outside of the end plate is screwed into the screw hole, and the convex portion or the concave portion of the dowel tip surface is attached to the pressure plate. It is characterized in that it is fitted in the concave portion or the convex portion.

[Action]

According to the above configuration, since the convex portion or the concave portion of the dowel tip surface is fitted in the concave portion or the convex portion of the pressure bearing plate, the pressure bearing plate may be attached to the end plate through one bolt. Therefore, the rotation of the pressure bearing plate around the bolt is prevented.

〔Example〕

 Embodiments of the present invention will be described below with reference to the drawings.

1 (a) and 1 (b) show an example of a post-tensioning prestressed concrete member. In the figure,
Reference numeral 1 is a concrete sleeper and 1'is a concrete track slab. 2 ... is an unbonded PC steel material embedded in a concrete sleeper 1 or a concrete track slab 1 ', 3 ... is a P
Pressure-bearing plates on the fixed end side of the C steel material 2 ... are pressure-bearing plates on the tensioned end side of the PC steel rods 2. Two pieces of the PC steel material 2 are inserted into the pressure bearing plates 3 ... 4 in the concrete sleeper 1 and the pressure bearing plates 3 ... 4 located at both longitudinal ends of the concrete track slab 1 '. .

The present invention is a formwork for manufacturing a concrete sleeper 1, a concrete track slab 1 ', or other prestressed concrete members, by using a bearing plate 3 on the fixed end side in which a plurality of PC steel materials 2 ... On the other hand, it is attached by the following device.

That is, as shown in FIGS. 2 to 5, a concrete sleeper manufacturing mold 5 (a groove-shaped mold body 6 for molding the side surface and the upper surface of the concrete sleeper 1 and the end plates 7 and 8 for molding the end faces). And the end plates 7 and 8 are detachably connected to both ends of the form body 6 in the longitudinal direction.) The structure of the pressure bearing plate mounting device A according to the present invention will be described as follows. is there.

As shown in FIGS. 3 and 4, two dowels 9 ... Are projected from the end plate 7 and integrated by welding. The structure of each dowel 9 is as shown in FIGS. 5 and 6, in which a bolt insertion hole 10 is formed in the central portion, the outer peripheral surface S ₁ is drafted, and the tip surface S ₂ has a diameter. Two convex portions 11 ... Are provided at symmetrical positions in the direction. Reference numeral 12 denotes a flange portion formed on the outer end of the dowel 9, which abuts the hole edge portion of the end plate 7 and defines the amount of protrusion of the dowel 9 inward of the mold. The bearing plate 7
Has two PC steel material insertion holes 13a and 13b, and these P
C Screw hole located at the center position between the steel material insertion holes 13a and 13b
14 and the convex portions 11 ..., that is, the screw holes 14
Two concave portions 15 ... Which are vertically symmetrical with respect to the center are formed.

Then, the fixed end sides of the PC steel materials 2 are inserted into the PC steel material insertion holes 13a and 13b of the pressure support plate 7, respectively, and in this state, the bolt 16 is inserted from the outside of the end plate 7 into the bolt insertion hole of the dowel 9.
Insert 10, the screwing tip of the bolt 16 into the screw hole 14, the convex portion 11 of the dowel tip surface S ₂ ... a, Bearing plate 7
It is fitted in the concave portion 15 of. In this case, the convex portions 11 ...
Since the concave portions 15 are provided symmetrically in the vertical direction, the pressure bearing plate 7 is
Even when they are placed upside down in the mold, the convex portions 11 ... And the concave portions 15 ... Fit.

According to the above configuration, the rotation of the pressure bearing plate 7 around the bolt 16 due to the vibration at the time of placing concrete is prevented by the fitting of the convex portions 11 ... And the concave portions 15.

After demolding, the tension work of the PC steel material 2 ... is performed, and then the dowel holes formed in the end face of the sleeper are filled with mortar, concrete, etc., so that the concrete sleeper 1 shown in FIG. You can get it.

In addition, the pressure support plate 4 for the end plate 8 of the PC steel material 2 ...
The structure of the mounting device of ... Is the same as the conventional one, and therefore the description thereof is omitted. The protrusions 11 may be formed by embedding a pin or a screw shaft in the distal end surface S ₂ of the dowel 9 in a partially protruding state, but in this embodiment, a steel ball is used. After the embedding and caulking steps, induction hardening is performed to form the protrusions 11 ... With the protruding portions of the steel balls. The recesses 15 on the pressure bearing plate 3 side may be formed by holes penetrating the pressure bearing plate 3, but in this embodiment, the recesses 15 are formed into spherical recesses corresponding to the protruding portions of the steel balls. It is formed on. Further, in this embodiment, the convex portion
11 ... and the recess 15 ... are provided symmetrically in the vertical direction, the recess 15
If two ... Are provided symmetrically, even if only one convex portion 11 is provided, the convex portion 11 and the concave portion 15 are fitted to each other regardless of the upper and lower sides of the pressure bearing plate 3. The convex portion 11 ... and the concave portion 15
... may be arranged in the lateral direction. In this case, as shown in FIG. 7, the recesses 15 may be formed in a groove shape. Further, the number of PC steel material insertion holes 13a and 13b formed in one bearing plate 3 is
It suffices if the number is plural, and it is also possible to form four or more PC steel material insertion holes 13a ..., 13b ... As shown in FIGS. Reference numeral 2a in FIG. 9 denotes a nut screwed to the end of the PC steel material 2.

In each of the above embodiments, the convex portion 11 is provided on the dowel 9 side and the concave portion 15 is provided on the pressure bearing plate 3 side. On the contrary, the concave portion 15 is provided on the dowel 9 side and the pressure bearing plate 3 is provided. Of course, the convex portion 11 may be provided on the side. However, since it is usual that the convex portion 11 has a higher processing cost than the concave portion 15, the concave portion 15 is provided on the side of the bearing plate 3 that is embedded in the prestressed concrete member as in the illustrated embodiment. It is more economical to provide the convex portion 11 on the dowel 9 which is a constituent member on the mold side and which is diverted many times.

[Effect of device]

The present invention, which has the above-described structure, reduces the number of dowel holes formed on the end surface of the concrete member after demolding, simplifies the work of filling the dowel holes, and places the dowel holes at a position away from the PC steel material. Since it is formed, P due to cracks in the filling part and poor adhesion between the filling part and the first concrete part, etc.
In addition to the advantages of preventing adverse effects on the C steel material, the following effects can be achieved.

That is, since the convex portion or the concave portion of the dowel tip surface is fitted into the concave portion or the convex portion of the pressure bearing plate, the pressure bearing plate is attached to the end plate regardless of whether the pressure bearing plate is attached to the end plate through one bolt. Rotation around the bolt is prevented, and the pressure bearing plate does not unexpectedly rotate due to vibration during concrete pouring, and the PC steel material can be accurately embedded in a predetermined position.

Further, since the pressure bearing plate is prevented from rotating by fitting the convex portion or the concave portion of the dowel tip surface and the concave portion or the convex portion of the pressure bearing plate, as in the conventional example described at the beginning, the hole of the rotation preventing tool is provided on the concrete surface. This is not possible, and the work of filling holes due to the rotation prevention tool is unnecessary.

[Brief description of drawings]

1 to 6 show an embodiment of the present invention, and FIGS. 1 (a) and (b) are schematic perspective views of concrete sleepers and concrete track slabs, which are examples of post-tensioning prestressed concrete members. 2 is a schematic vertical side view of a concrete sleeper manufacturing formwork, FIG. 3 is a schematic plan view of a concrete sleeper manufacturing formwork, FIG. 4 is a perspective view of a bearing plate mounting device, and FIG. 5 is a bearing plate mounting device. FIG. 6 is a vertical cross-sectional side view, and FIG. 6 is an exploded perspective view of the pressure bearing plate mounting device. FIG. 7 is an exploded perspective view of a pressure bearing plate mounting device showing another embodiment of the present invention. FIG. 8 is a front view of a bearing plate showing another embodiment of the present invention, and FIG.
The figure is a vertical cross-sectional side view of a main part in a state where the pressure bearing plate is attached. 10 to 12 show a conventional example, FIG. 10 is a vertical sectional side view, FIG. 11 is a vertical sectional front view, and FIG. 12 is a vertical sectional side view. A ... Pressure plate mounting device, 2 ... PC steel material, 3 ... Pressure plate, 5
… Formwork, 7… Cable plate, 9… Dowel, 11… Convex part, 15… Concave part, 16
…bolt.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Hiromi Inoue, 2-8, Hikarimachi, Kokubunji, Tokyo 38, Incorporated Railway Technical Research Institute (72) Yoshinori Kudo 2-25, Mutsukawa, Minami-ku, Yokohama-shi, Kanagawa Four

Claims (1)

[Scope of utility model registration request] 1. A post-tension type prestressed concrete member manufacturing form has a bolt plate on the fixed end side of a PC steel material, a hole for bolt insertion is formed in the center, a draft is formed on the outer peripheral surface, and a tip end surface is formed. A dowel provided with a convex portion or a concave portion is projectingly provided, and a plurality of PC steel material insertion holes, screw holes located between these PC steel material insertion holes, and a concave portion or a convex portion corresponding to the convex portion or the concave portion are provided. The fixed end sides of the PC steel materials are inserted into the PC steel material insertion holes of the formed pressure bearing plate,
The tip of the bolt inserted into the bolt insertion hole of the dowel is screwed into the screw hole from the outside of the end plate, and the convex portion or concave portion of the dowel tip surface is fitted into the concave portion or convex portion of the pressure bearing plate. A support device for mounting a pressure plate in a mold for manufacturing a pretensioned prestressed concrete member, which is characterized in that