JPH09273122A - Joint mechanism for placing bridge girder floor slab - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a joint mechanism for placing a bridge girder floor slab facilitating the installation and removal work thereof and using constitutive elements capable of being repeated used. SOLUTION: Air-tight hollow bodies 1 and 2 are inserted among groups adjacent to up and down of a group of distributing bars 10 of a bridge girder going to place concrete and are extended widthwise of the bridge girder. A substance having rigidity capable of holding flatness of the front standing approximately upright to place and one or both of up and down faces adjacent thereto, elastic body 3 is placed between substances arranged and adjacent to up and down among the air-tight hollow bodies 1 and 2, a substance having thicker diameter than as of reinforcing bars forming the distributing bars 10 and a high pressure gas introducing device for introducing the high pressure gas into the air-tight hollow bodies are provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pour seam mechanism for forming a seam in a concrete slab construction work for a bridge floor.

[0002]

2. Description of the Related Art A floor slab of a bridge is formed by arranging reinforcing bars vertically and horizontally, surrounding the reinforcing bars with a formwork, and then pouring concrete there. That is, as shown in the vertical cross-sectional view of FIG. 12 and the lateral cross-sectional view of FIG. 13 shown in FIG. 13, the length of the bridge is maintained with a substantially constant interval in the vertical direction and the width direction of the bridge. The bridge so as to surround the distribution reinforcing bar 10 extending in the vertical direction and the main reinforcing bar 12 extending in the orthogonal direction to the distribution reinforcing bar 10 while keeping a substantially constant interval in the vertical direction and the length direction of the bridge. A slab form 9 is formed and concrete is poured into the inside. Diameter of rebar is typically 16 mm
The diameter of the main rebar is about 19 mm. The distance between the distribution reinforcing bars and the main reinforcing bars is 10 cm to 30 cm between the centers, and the thickness of the floor slab is about 20 cm to 25 cm.

Ideally, the concrete pouring work for forming the floor slab is completed once in the entire length of the bridge. However, in reality, there is a limit to the ability to drive the construction, so the total length of the bridge is divided into multiple sections,
Each section is sequentially placed in multiple times. In this case, the end of the section to be placed is called a joint, and at this joint a damming mechanism called a joint form is formed to dam the concrete that has been cast until it solidifies. To be done.

A conventional seam joint form has a structure as shown in FIGS. 12 and 13. A plurality of wooden barrier plates 21 divided in the width direction of the bridge are fixed on the formwork 9 by the piers 22 in an upright state, and are reinforced by the wooden support members 24 with the piers 22 interposed. And a wooden thin plate 23 continuous in the width direction of the bridge for closing the gap between the weir plates 21.
Are arranged between the upper and lower distribution reinforcing bars 10 and between the main reinforcing bar 12 and the formwork 9. On the uppermost part, a wooden flap square frame member 8 for fixing the dam plate 21 and for forming the joining surface in a staircase shape of interlocking is arranged. The above-mentioned interlocking wooden members are connected by nailing.

[0005]

In the above-mentioned conventional seam formwork, since the continuity is obstructed by the reinforcing bars arranged in a complicated manner in the vertical and horizontal directions, the dam plate 21 is divided into a large number of parts. Despite being a relatively small structure, there is a problem that the work for installing and removing the structure requires a great deal of labor and time. Further, since the formwork has to be installed in a narrow space where the reinforcing bars are intricate, a skilled formworker is required, which causes a problem that the construction cost is high.

In the above-mentioned conventional seam form, there is also a problem that a large number of weir plates are required even if a part of the weir plate is reused. For example, for a bridge with a total length of 200 meters and a width of about 12 meters, the required number of joints at one location is 85, and the number of joints at eight is estimated to be 680. There is also the problem that frame installation costs will rise sharply. Therefore, it is an object of the present invention to provide a strut-joint mechanism that uses components that are easy to install and remove and that can be used repeatedly.

[0007]

According to the strut joint mechanism of the present invention which solves the above-mentioned problems of the prior art, it is inserted between vertically adjacent ones of the distribution reinforcing bars and extended in the width direction of the bridge. An airtight hollow body having rigidity such that one or both of the front face and the upper and lower faces adjacent to the upright face which are arranged upright have rigidity such that flatness can be maintained. A plate-like elastic body arranged between adjacently arranged ones having a thickness larger than the diameter of the reinforcing bar, and high-pressure gas introduction means for introducing high-pressure gas into the airtight hollow body. ing.

[0008]

According to an embodiment of the present invention, a cap is detachably attached to both ends of an airtight hollow body in a state where it can be held airtight, and the length of the elastic airtight hollow body is a bridge. Is set to a value approximately equal to the width of.

[0009]

FIG. 1 is a sectional view showing the construction of a strut joint mechanism according to an embodiment of the present invention, and FIG. 2 is a sectional view taken along the line A--A in FIG.
In FIG. 1 and FIG. 2, 1 and 2 are tube molds, which are an example of an airtight hollow body, 3 is packing, 5 and 6 are caps, and 8 is square flap frame material. Further, 9 is a bridge slab formwork, 10 is a distribution reinforcing bar, and 11 is a main reinforcing bar.

As shown in the enlarged cross-sectional view of FIG. 3, the tube form 1 has airtightness as a whole by the elastic tube 1a made of rubber, and is placed between the vertically adjacent force distribution rebars. The upright front surface and the upper surface adjacent thereto can be kept flat even under the presence of internal air pressure or external force by being reinforced by the steel plates 1b and 1c inserted inside. It has a certain degree of rigidity.

At the trial production stage for developing the piecing joint mechanism of this embodiment, a vehicle rubber tube is used as the tube 1a, and thin spring steel strips are used as the steel plates 1b and 1c. The height of the front surface of the tube form 1 is set to be a value slightly smaller than the vertical distance between the reinforcing bars. Further, the length of the tube formwork 1 is set to a value substantially equal to the lateral width of the bridge. The tube formwork 2 is also the above-described tube formwork 1 except for the dimension of the height of the front surface thereof.
Has the same structure as

As shown in the enlarged sectional view of FIG. 4, the packing 3 has a rod-shaped elastic body 3a having a rectangular cross section and a length substantially equal to the lateral width of the bridge, and is adhesively fixed to the upper portion of the elastic body 3a. And the reinforcing steel plate 3b.
In this embodiment, as the elastic body 3a, a foamed rubber containing closed cells, which is commercially available under the trade name of "Reston sponge", is used, and a thin spring steel strip is used as the reinforcing steel plate 3b. The thickness of the elastic body 3a is set to a value slightly larger than the diameter of the reinforcing bar. Also, the elastic body 3a
In order to reduce the rigidity of No. 3, a semicircular cutout is formed on the side where the steel plate 3b is not adhered.

As shown in the front view of FIG. 5 and the sectional view of FIG. 6, the cap 5 has a thick plate-like body 5a and this plate-like body 5a.
A flange portion 5b protruding from the peripheral portion of a in a direction substantially perpendicular to the plate-shaped body is provided. The plate-shaped body 5a is shown in FIG.
The tube form 1 shown in FIG. 3 has a shape that is substantially similar to the cross-sectional shape and a size that is slightly large enough to accommodate the end of the tube form 1 inside the collar 5b.

The bolt 5e is removably inserted into the counterbore hole formed in the plate-like body 5a with the airtight washer 5h attached to the neck of the bolt 5e, so that the plate-like body 5a is connected to the flange 5b. It is made to project almost at a right angle. In the vicinity of the tip of the bolt 5e, an elastic plate 5d having a shape that is substantially similar to the cross-sectional shape of the tube form 1 and a size that is slightly small enough to be inserted into the end of the tube form 1 is provided. It is held while interposing. A metallic pressing plate 5c having the same shape as the elastic plate 5d is fixed to the tip of the bolt 5e by being screwed into the bolt 5e.

As shown in FIG. 6 (A), the tube form 1
The bolt 5e is rotated in a state in which the cap 5 is capped on the end of the tube form 1 so that the end of the cap is located between the flange 5b, the elastic plate 5d, and the pressing plate 5c. Along with this, the pressing plate 5c, which is prevented from rotating smoothly by the tube form 1, approaches the plate-shaped body 5a along the axial direction of the bolt 5e while pressing the elastic plate 5d. FIG. 6 (B)
When the elastic plate 5d is strongly pressed from both sides by the plate-shaped body 5a and the pressing body 5c, the thickness thereof is reduced and the outer diameter is increased, as shown in FIG. As a result, the end portion of the tube form 1 is strongly sandwiched between the elastic plate 5d that has expanded in the radial direction and the flange 5b to such an extent that the airtight state can be maintained, and the tube form 1 becomes the airtight state. The helical spring 5f prevents the hole for passing the bolt 5e formed inside the elastic plate 5d from being crushed when the plate body 5d is compressed in the thickness direction and expanded in the radial direction. belongs to.

As shown in the sectional view of FIG. 7, a vent hole 5i communicating with the inside of the tube form 1 is formed in the elastic plate 5d and the pressing plate 5c at the rear portion of the cap 5 and communicates with this vent hole 5i. A vent hole 5j is formed inside the plate-like body 5a, and an air injection valve 5k communicating with the vent hole 5j is formed in the plate-like body 5a.
It is attached to the rear end of a. In addition, the string spring 5g
Similarly to the coiled spring 5f arranged around the bolt 5e, the vent hole 5i formed inside the elastic plate 5d is crushed when the elastic plate 5d is compressed in the thickness direction and expanded in the radial direction. It is to prevent it from being released.

The caps 6 attached to both ends of the tube form 2 also have the same structure as the cap 5 described above except for the difference in size due to the difference in size between the tube forms 1 and 2. There is. Therefore, the description of the cap 6 which is the same as that of the cap 5 is omitted.

Next, a method of assembling the joint structure of the above embodiment will be described. Referring to FIG. 1 and FIG. 2, first, the flutter square frame member 8 is placed on the distribution reinforcing bar at the upper portion of the place where the joint is to be formed. Next, the tube formwork 1 is inserted between the formwork 9 and the lower distribution reinforcing bar 10. This tube form 1 has a length almost equal to the width of the bridge, and the cap 5 is not yet crowned, and the form 9 and the lower distribution reinforcing bar 10 are in a soft state that is easy to bend.
Inserted between This tube formwork 1 includes a steel plate 1b.
The front surface reinforced by is placed in an upright state, and the surface reinforced by the steel plate 1c is placed on the upper side.

Subsequently, the packing 3 having a length substantially equal to the lateral width of the bridge is placed on the tube form 1 from above the lower distribution reinforcing bar 10. The packing 3 is placed on the tube form 1 with the reinforcing steel plate 3b facing upward so as to wrap the lowermost distribution reinforcing bar 10 with the soft elastic body 3a.

Next, the tube form 2 is inserted between the packing 3 and the upper reinforcing bar 10. This tube form 2 has a length approximately equal to the lateral width of the bridge, and is between the packing 3 and the upper distribution reinforcing bar 10 in a soft state where the cap 6 is not yet crowned and is easily bent. Inserted in. The tube form 2 is arranged such that the front surface reinforced by the steel plate 2b is in an upright state and the surface reinforced by the steel plate 2c is on the lower side. Then, the packing 3 is placed on the tube form 2 with the reinforcing steel plate 3b facing downward so that the packing 3 is wrapped by the soft elastic body 3a.

Next, as already described with reference to FIGS. 6 (A) and 6 (B), both ends of the tube form 1 are capped with the caps 5 and the bolts 5e are rotated, whereby both ends thereof are rotated. Keep the section airtight. Similarly, caps 6 are capped on both ends of the tube form 2 and corresponding bolts are rotated to make both ends airtight. Next, an air compressor is connected to the air injection valve 5k via a connector and a hose, and high-pressure air is filled in the tube mold 1 kept airtight. Similarly, the inside of the tube form 2 is also filled with high-pressure air.

In the tube form 1, the upright surface of which rigidity is increased by inserting the steel plate 1b in the state where the high pressure air is filled in the tube form 1 is a flat upright surface even under the pressure of the poured concrete. Hold the state. The same applies to the tube mold 2. Further, the elastic body 3b of the packing 3 is accompanied by filling high-pressure air from the upper surface of the tube formwork 1 whose rigidity is increased by inserting the steel plate 1c and the lower surface of the tube formwork 2 whose rigidity is increased by inserting the steel plate 2c. Although the thickness is reduced by receiving a strong pressing force, at this time, the distribution reinforcing bars 10 are tightly wrapped from three sides to reduce the voids in their peripheral portions and prevent the poured concrete from leaking.

Concrete is cast using the joint mechanism of the present invention formed according to the above procedure. After the concrete is solidified, the high-pressure air is released from the inside of the tube molds 1 and 2 by opening the air injection valve 5k.
By rotating the bolts of the caps 5 and 6 in the counterclockwise direction and moving them into the inside of the cap, and returning from the state of FIG. 6B to the state of FIG. Remove from both ends of 2. After this, the tube formwork 1, 2 and packing 3 are pulled out from the gap of the reinforcing bar 10 to remove the joint structure.

FIG. 8 is a sectional view showing the construction of another embodiment of the joint structure of the present invention. In this figure, the components denoted by the same reference numerals as those in FIGS.
The components are the same as those already described with respect to these figures, and duplicate description thereof will be omitted. In this embodiment, two types of tube molds 1 having different sizes are used.
Instead of using 2 and one type of packing 3, one type of tube mold 1 and two types of packing 3 and 4 of different thickness are used.

FIG. 9 is a plan view showing the construction of a strut joint mechanism of still another embodiment of the present invention. FIG. 10 is a side view seen from the direction C of FIG. 9, and FIG. 11 is a side view of FIG. It is a B sectional view. In the figure, the constituent elements denoted by the same reference numerals as those in each of FIGS. 1 to 7 are the same as the constituent elements already described with reference to these figures, and duplicate description thereof will be omitted.

In this embodiment, the tube formwork 1 is prepared separately for the long tube formwork 1A and the short tube formwork 1B, and the long one is used depending on the width of the bridge on which concrete is to be placed. The short width and the short width are selected and used by connecting them to each other with the sheath cover 7 so that the width is almost equal to the lateral width of the bridge. It is also possible to prepare only one type of long tube mold 1A having a fixed length and to prepare a plurality of short tube molds 1B having various lengths.

The structure in which the packing arranged between the tube molds is pressed against the distribution bar from above or below has been described above. However, for the purpose of preventing the leakage of concrete immediately after pouring by further narrowing the gap formed between this packing and the distribution reinforcing bar, the packing is sandwiched between the upper and lower sides of the distribution reinforcing bar. It is also possible to adopt a configuration in which it is arranged between the molds.

Further, the case where a tube form having elasticity is used as the airtight hollow body is illustrated. However, it is also possible to use an airtight hollow body having no elasticity, such as a cloth lined with rubber.

As described in detail above, in the strut joint mechanism of the present invention, one or both of the upright front surface and the upper and lower surfaces has rigidity such that flatness can be maintained, and an elastic body is used as the airtight hollow body. Since it is configured to be placed between the upper and lower adjacent ones of the force distribution rebar group while being interposed, the work of installation and removal is easy, and the components can be used repeatedly, and the construction cost can be reduced. .

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing the structure of a bridge joint mechanism for placing a bridge floor slab according to one embodiment of the present invention, together with the relationship between distribution reinforcing bars, main reinforcing bars and floor slab formwork.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is an enlarged cross-sectional view of the tube mold 1 in FIG.

FIG. 4 is an enlarged cross-sectional view of packing 3 in FIG.

5 is a front view of the cap 5 in FIG. 2. FIG.

6 is a sectional view taken along line AA of FIG.

FIG. 7 is a sectional view taken along line BB of FIG. 5;

FIG. 8 is a cross-sectional view showing the configuration of a bridge joint mechanism for placing a bridge floor slab according to another embodiment of the present invention, together with the relationship between distribution reinforcing bars, main reinforcing bars and floor slab formwork.

FIG. 9 is a plan view showing a configuration of two types of tube molds 5 having different lengths which constitute a pour seam mechanism for placing a bridge deck according to still another embodiment of the present invention.

10 is a C arrow view of a connecting portion between the tube molds 1A and 1B of FIG. 9.

11 is a sectional view taken along line BB of FIG. 9.

FIG. 12 is a cross-sectional view showing the configuration of a conventional joint seam form, together with the relationship between the distribution reinforcing bar, the main reinforcing bar and the floor slab form.

13 is a cross-sectional view taken along the line DD of FIG.

[Explanation of symbols]

 1,2 Tube form (airtight hollow body) 3,4 Packing (elastic body) 1a, 2a Elastic tube 1b, 1c Reinforcing steel plate 2b, 2c Reinforcing steel plate 3a Elastic body 3b Steel plate 5,6 Cap 5a Plate 5c Pressing plate 5d Elastic plate 9 Floor slab 10 Forming bar 11 Main bar

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor, Jiichi Sato 1-6-6, Sakata-shi, Yamagata Prefecture Hayashi Construction Industry Co., Ltd. (72) Noboru Naito 1-6-6, Saiko-shi, Sakata-shi, Yamagata Prefecture Hayashi Kensetsu Kogyo Co., Ltd. (72) Inventor Goichiro Takahashi 1-6-6 Sachimachi Sakata, Yamagata Prefecture Hayashi Kensetsu Kogyo Co., Ltd.

Claims (4)

[Claims] Claim: What is claimed is: 1. A first rebar group extending in the length direction of the bridge while maintaining a substantially constant distance in the up-down direction and the width direction of the bridge, and in the up-down direction and the length direction of the bridge. When placing concrete in a bridge deck stencil formed by surrounding a first reinforcing bar group and a second reinforcing bar group extending in a state orthogonal to the first reinforcing bar group at a constant interval, A strut-joint mechanism formed to divide an installation target region in a length direction of a bridge, and is inserted between vertically adjacent groups of the first reinforcing bar group and extended in a width direction of the bridge. It is an airtight hollow body,
A front surface arranged substantially upright and one or both of upper and lower surfaces adjacent to the front surface have rigidity such that flatness can be maintained, and the airtight hollow bodies are arranged vertically adjacent to each other. An elastic body disposed between objects and having a thickness larger than the diameter of the reinforcing bars constituting the first reinforcing bar group; and a high-pressure gas introducing means for introducing high-pressure gas into the airtight hollow body. A joint structure for placing bridge decks, which is characterized by 2. The bridge joint construction for bridge deck siding according to claim 1, wherein caps are attached to both ends of the airtight hollow body in a detachable and airtight manner. 3. The bridge seam mechanism for placing a bridge deck according to claim 1 or 2, wherein the airtight hollow body has a length substantially equal to a width of the bridge. 4. The pour seam mechanism for placing a bridge deck according to claim 1, wherein a plurality of airtight hollow bodies having different lengths are combined.