JP3169544U - Grout formwork - Google Patents

Abstract

The present invention proposes a grout formwork that enables high-quality prestressed concrete work to be carried out quickly and inexpensively. A grout mold frame 1 capable of attaching / detaching a prestressed concrete structure to / from an anchor head 2, comprising a box-shaped steel member 10 having one end face shielded and the other end face opened. A through hole 13 is formed in the inner space of the steel member 10 so as to have a truncated cone shape that gradually increases in diameter from one end to the other end. [Selection] Figure 1

Description

  The present invention relates to a grout form for preventing leakage of PC grout.

  In prestressed concrete (hereinafter simply referred to as “PC”) construction, the tension material (PC steel material) is rusted and the tension material is secured after the tension material is tensioned (strain material and sheath tube). PC grout is injected in between.

Conventionally, the injection of PC grout has been generally performed after curing the concrete placed in the boxed portion (around the tension material head) at the end of the tension material.
However, in the conventional PC grout injection, the time from the tension of the tension material to the grout injection is long, which hinders the shortening of the work period, and the tension material (PC steel material) and the fixing tool may corrode.

Therefore, for the purpose of injecting the PC grout immediately after the tension of the tension material, the PC grout is injected in a state where the cap for preventing leakage is fixed to the head of the tension material, and then the concrete is placed in the boxed portion. There is a case.
By doing so, leakage of the grout material from the gap between the anchor head and the tension material can be prevented.

If a resin-type cap that is not a diversion type is used as a leakage prevention cap, foreign matter remains in the structure. On the other hand, when a diversion type resin cap is used, the number of diversions decreases.
In addition, when a pressure-resistant cap made of buried type steel that is not a diversion type is used, there is a problem that the construction cost increases.

  An object of the present invention is to solve the above-mentioned problems and to propose a grout formwork that enables high-quality PC construction to be carried out quickly and inexpensively.

In order to solve the above-described problems, the present invention is a grout mold frame that can be attached to and detached from a PC fixing portion of a prestressed concrete structure, and is a box-shaped steel that is shielded at one end and opened at the other end. A through hole is formed in the one end surface, and the internal space of the steel member is formed in a truncated cone shape that gradually increases in diameter from the one end surface side toward the other end side. It is characterized by that.
Here, in this specification, the “PC fixing portion” refers to an anchor head, a head of a tension material (PC steel material), or the like.

  According to such a grout form, since the internal space is formed in a truncated cone shape, demolding is easy. Therefore, the grout form can be easily diverted, and as a result, the construction cost can be reduced.

Moreover, since the through-hole (discharge port) is formed in the end surface, it is possible to confirm the state of grout injection. Therefore, high quality construction with grout injection is possible.
Furthermore, if a grout formwork is used, grout injection can be carried out immediately after the tension of the tendon, so that the workability is excellent.

  If a plurality of bolt holes are formed in the peripheral part of the steel member and are fixed to the PC fixing part through bolts penetrating the bolt holes, the grout form frame can be attached and detached by attaching and detaching the bolts. Can be easily performed.

  If the other end surface of the steel member is provided with a packing, leakage of the grout from the gap between the fixing tool and the grout mold can be prevented.

  According to the grout formwork of the present invention, high-quality PC work can be carried out quickly and inexpensively.

It is sectional drawing which shows the attachment condition of the grout formwork which concerns on embodiment of this invention. (A) is a side view of a grout formwork, (b) is an A arrow view of (a), (c) is a front view of packing. (A)-(c) is sectional drawing which shows each construction condition of PC construction.

Embodiments of the present invention will be described with reference to the drawings.
As shown in FIG. 1, the grout mold 1 of this embodiment is fixed to an anchor head (PC fixing unit) 2, thereby preventing leakage of the PC grout 3 when the PC grout 3 is injected. The grout mold 1 is fixed so as to cover the heads (PC fixing portions) of the PC steel materials (tension materials) 4, 4,.

  The grout mold 1 includes a steel member 10 and a packing 20 as shown in FIG.

The steel member 10 is formed in a box shape with one end face shielded and the other end face opened.
The steel member 10 has sufficient proof strength so as not to be deformed by the grout injection pressure.

  The internal space 11 of the steel member 10 is formed in a truncated cone shape whose diameter gradually increases from one end side (the bottom surface 12 side) toward the other end side (opening side). That is, in the internal space 11, the inner wall surface is tapered so that the sectional area on the opening side is larger than the sectional area on the bottom surface 12 side.

  A through hole 13 is formed in one end surface (bottom surface 12) of the steel member 10. The through hole 13 functions as an air vent hole when injecting the PC grout and also functions as a confirmation hole for confirming the filling state of the PC grout 3.

  In the present embodiment, the through hole 13 is formed in the peripheral edge portion of the bottom surface 12, but the position of the through hole 13 is not limited. For example, it may be formed at the center of the bottom surface 12. Further, the through hole 13 may be formed in the side wall portion of the steel member 10.

  As shown in FIG. 2 (b), a plurality of (four in this embodiment) bolt holes 14, 14,...

As shown in FIG. 1, the steel member 10 is detachably fixed to the anchor head 2 via a bolt 30 inserted through the bolt hole 14.
The number and arrangement of the bolt holes 14 are not limited as long as the steel member 10 can be brought into close contact with the anchor head 2.

On the outer surface on one end side of the steel member 10, a step (convex portion) 15 is formed. The steel member 10 can be easily handled when the grout form 1 is attached or detached by using the step 15 as a handle.
The step 15 may be formed as necessary and may be omitted.

  The packing 20 is installed in the other end surface (opening side end surface) of the steel member 10 as shown in FIG.

The packing 20 is a resin member, and is formed in an endless shape having a planar shape equivalent to the planar shape of the other end surface of the steel member 10 as shown in FIG.
In the packing 20, a plurality of bolt holes 21, 21,... Are formed corresponding to the positions of the plurality of bolt holes 14, 14,.

  Since the packing 20 is interposed between the steel member 10 and the anchor head 2, the PC grout 3 is prevented from leaking from between the steel member 10 and the anchor head 2 when the PC grout 3 is injected. ing.

  As shown in FIG. 1, the anchor head 2 is arranged in close contact with the surface of the bearing plate 5 embedded in the concrete member C.

The anchor head 2 has a plurality of insertion holes 2a through which the PC steel material 4 is inserted.
The insertion hole 2a has a diameter that increases from the central portion in the thickness direction of the anchor head 2 toward one end side (the grout mold 1 side), and is formed in a shape that allows the wedge 8 to be press-fitted.

Further, bolt holes 2b and 2b for screwing the bolts 30 are formed on the periphery of the anchor head 2.
A packing 6 is interposed between the anchor head 2 and the bearing plate 5.

  The bearing plate 5 of the present embodiment is a so-called trumpet type bearing plate having a bearing plate portion 5a and a tubular portion 5b. In addition, the structure of the bearing plate 5 is not limited, A plate-shaped bearing plate may be sufficient.

A grout injection hole 5c is formed in the support plate 5a, and the PC grout 3 can be injected into the gap between the PC steel material 4 and the support plate 5.
The grout injection hole 5c is opened on the surface of the concrete member C.

  In the present embodiment, a prestressing force is introduced into the concrete member C by a plurality of PC steel materials 4, 4,.

As shown in FIG. 1, the PC steel material 4 is inserted through a sheath tube 7 embedded in a concrete member C.
Although the material which comprises the PC steel material 4 is not limited, For example, what is necessary is just to use a PC steel bar, a PC steel wire, a PC steel strand, etc.

  In the PC construction using the grout form 1 of the present embodiment, first, the anchor head 2 is brought into close contact with the bearing plate 5, and the PC steel materials 4, 4,... Penetrating the bearing plate 5 and the sheath tube 7 are attached to the anchor head 2. Is inserted into the insertion hole 2a (see FIG. 3A).

  Next, when the PC steel materials 4, 4,... Are tensioned and a predetermined tension is introduced, the wedges 8, 8,... Are press-fitted into the respective insertion holes 2a as shown in FIG. As a result, the PC steel materials 4, 4,... Are fixed to the concrete member C by the wedge action, and prestress is introduced into the concrete member C.

Next, as shown in FIG. 3B, the grout mold 1 is fixed by screwing bolts 30 through which the bolt holes 14 are inserted into the anchor head 2.
The grout form 1 is fixed to the anchor head 2 with the heads of the PC steel materials 4, 4,.
At this time, a release material is applied to the inner surface of the steel member 10.

Subsequently, the grout 3 is injected from the grout injection hole 5c. The grout 3 is injected until the inner space 11 of the steel member 10 is filled with the grout 3.
In this embodiment, a hose nipple (not shown) is installed in the grout injection hole 5c, and the grout 3 is injected in a state where the injection tube is connected to the hose nipple.

  The filling of the grout 3 into the internal space 11 is performed until the grout 3 from the through hole 13 flows out. A nipple (not shown) is installed in the through hole 13 as necessary.

When the filling of the grout 3 into the internal space 11 of the steel member 10 is confirmed, the grout 3 is cured until a predetermined strength is developed.
When a predetermined strength develops in the grout 3, the grout form 1 is removed as shown in FIG.

  As mentioned above, if the grout form 1 of this embodiment is utilized, PC grout 3 can be inject | poured immediately after tension | tensile_strength of PC steel materials 4,4, .... Therefore, corrosion of PC steel materials 4, 4,... Can be prevented.

  Since the grout form 1 of this embodiment is detachably installed via the bolts 30, no foreign matter remains in the concrete structure.

  Further, by diverting the grout formwork 1 (steel member 10), the construction cost can be reduced. The consumables are only the packing 20, the hose nipple, and the nipple.

  Moreover, since the inner space 11 of the steel member 10 is formed in a truncated cone shape, the grout mold 1 is easy to be removed from the mold, is excellent in workability, and the quality of the grout 3 can be visually confirmed.

  Heretofore, an example of a preferred embodiment has been described for the present invention. However, the present invention is not limited to the above-described embodiment, and the above-described constituent elements can be appropriately changed without departing from the spirit of the present invention.

  The application location of the grout formwork is not limited, and may be, for example, inside a box formed on a concrete member or on the surface of a concrete member.

  The method of fixing the steel member to the anchor head is not limited to fastening with bolts as long as it can be detachably fixed.

  In the above-described embodiment, the packing is interposed between the steel member and the anchor head. However, the packing may be interposed as necessary, for example, grease is applied to the end surface of the steel member. Thus, leakage of PC grout may be prevented.

1 Grout formwork 2 Anchor head (PC fixing part)
3 PC grout 4 PC steel (tensile material)
DESCRIPTION OF SYMBOLS 10 Steel member 11 Internal space 12 Bottom face 13 Through hole 14 Bolt hole 20 Packing 30 Bolt C Concrete member

Claims (3)

A grout form that can be attached to and detached from a PC anchorage of a prestressed concrete structure,
A box-shaped steel member having one end face shielded and the other end face opened;
A through hole is formed in the one end surface,
An inner space of the steel member is formed in a truncated cone shape that gradually increases in diameter from the one end toward the other end. A plurality of bolt holes are formed in the peripheral portion of the steel member,
The grout formwork according to claim 1, wherein the grout formwork is fixed to the PC fixing portion through a bolt penetrating the bolt hole. The grout formwork according to claim 1, wherein a packing is provided on the other end surface of the steel member.

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