JPH07102530A - Connecting device for precast slab - Google Patents

Abstract

PURPOSE:To shorten term of works without deteriorating ambient circumstances while improving safety by a method wherein adjoining precst slabs are connected at their sides with connecting members of specific shapes. CONSTITUTION:A plurality of precast slabs 1, each of which is equipped at its connecting side 8 with a first connecting metal fixture 3, are brought into a construction site beforehand. Two precast slabs 1 are placed, butting against each other. Both ends of a second connecting metal fixture 15 in H shape are inserted into each of T-shaped grooves 12 provided to the first connecting metal fixtures 3. Shearing keys 20 incorporated in the second connecting metal fixture 15 are made to project by insertion of wedges and at the same time, key grooves 11 of the first connecting metal fixtures 3 are engaged with the shearing keys 20. Compressive force between two adjoining precast slabs 1 is transmitted through the first connecting metal fixtures 3 and the second connecting metal fixtures 15.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a joining device for precast slabs which is applied to join adjacent side faces of precast slabs made of reinforced concrete arranged in parallel to each other to form a floor surface of a bridge or the like.

[0002]

2. Description of the Related Art The conventional bonding of precast floor slabs will be described with reference to FIGS. In the example shown in FIG.
The precast floor slab 01 is manufactured by preliminarily projecting a reinforcing bar 02 having a length that allows the lap joint length to the width direction of the precast floor slab 01 on the joint side surface of the precast floor slab 01 whose side surfaces are mutually coupled. And arrange them at intervals so that the lap joint length of the reinforcing bar 08 can be taken, and arrange the distributing bar 03 orthogonally to the reinforcing bar 02, and wire the intersection of the reinforcing bar 02 and the distributing bar 03. After staking with tie etc., the lower part and the side part of the joint part are covered with the formwork 04, concrete 05 is poured, and the adjacent precast floor slabs 01, 01 are joined.

In the above-mentioned connection, all the work except the production of the precast floor slab 01 performed in a factory or the like is a site work in a bad working environment such as on a bridge, so that the work efficiency is poor and the construction period is prolonged. At the same time, it is not preferable in terms of work safety. In particular, on the site, it is necessary to work on the lower surface of the precast floor slab 01, such as temporarily placing the formwork 04 around the joints in order to place concrete 05, so it is necessary to install, dismantle, and remove the scaffold. However, there is a problem that the construction period becomes long and there is a problem that a lot of work on the scaffold, which is not preferable for safety, increases. Furthermore, when replacing the precast floor slabs that have been combined and installed in this way, it is necessary to perform the dismantling work of the concrete 05 that has been placed in the joints and to remove the damaged precast floor slabs 01. Dust is generated during the chipping work, deteriorating the surrounding environment and lengthening the replacement period.
Precast floor slabs laid on bridges, etc. have been severely damaged due to the increase in traffic volume and the weight of vehicles in recent years, and they have to be replaced in a short period of time. There is a problem such as increasing the social loss.

Further, in another example shown in FIG. 7, precast floor slabs 01 whose side surfaces are connected to each other are arranged in parallel,
Mortar 06 is poured into the joint part of the mutual precast floor slab 01, and after curing, precast floor slab 01
The PC steel wire 07 is passed through the sheath 08, which is embedded in a plurality of rows in the width direction, and the precast floor slab 01 is prestressed and integrally joined by tensioning the PC steel wire 07. In this example, as compared with the above-mentioned conventional example, the work at the site is performed by injecting the mortar 06 to the bonding surface and P to the sheath 07.
Insertion of the C steel wire 07 and tension of the inserted PC steel wire 07 are considerably simplified, and further, temporary construction of the formwork, disassembly,
There is an advantage that the amount of work can be reduced and the construction period can be shortened because it does not need to be removed or only a small section is required.

However, also in the connection of this example, it is necessary to work on the lower surface of the precast floor slab 01 in order to shape the injection mortar 06, and the construction period for installing, dismantling and removing the scaffolding for that purpose becomes long. Moreover, unsafe work at the work site still remains.

Further, when replacing the precast floor slab, it is necessary to remove the mortar which is bonded to the precast floor slab, and the problem caused by this removal work is similar to the above-mentioned example, although the scale is small. .

Further, when manufacturing the precast floor slab 01, it is necessary to arrange the sheath 07 in a substantially straight line state in advance, and when the precast floor slab 1 is joined, the PC steel wire 07 is tensioned. There is a problem which is not in the conventional example shown in FIG.

[0008]

DISCLOSURE OF THE INVENTION The present invention solves the problems of the conventional precast floor slab joining device, and (1) is not suitable for work sites and is not preferable in terms of safety. (2) No need for a formwork to join the precast slabs, no scaffolding required for joining work, and (3) a smooth replacement of the new and old precast slabs. It is an object of the present invention to provide a precast floor slab connecting device that can be completed and can complete the connecting work in a short period of time.

[0009]

For this reason, the connecting device for the precast floor slab of the present invention is a combination of the following first and second connecting devices and a shear key. (1) The first coupling device: -The outer shape is formed into a substantially rectangular parallelepiped, and both side surfaces and the rear side surface thereof are inserted into one of the concave portions formed to face each of the coupling side surfaces of the adjacent precast floor slabs. The pre-cast floor slab was fixed by placing the front side surface on the same side as the connecting side surface. -An opening opening in the central portion of the front side surface was provided so as to penetrate in the thickness direction of the precast floor slab. -A keyway is formed by providing a notch in the middle of the opening in the plate thickness direction that is parallel to the connecting side surface. An engaging portion, which is connected to the opening portion and is wider than the opening portion width and smaller than the front side surface width, is provided at the rear side in the thickness direction of the precast floor slab. When viewed in the plate thickness direction of the precast floor slab of the fixed first coupling device, the opening is formed in the T-shaped groove forming the lower part (leg) of the T-shape and the engaging part is formed in the T-shaped groove forming the upper part of the T-shape. did. (2) The second coupling device is: -The outer shape is formed into a substantially H shape, one of the H shapes can be inserted into the T-shaped groove of the opposing first coupling device, and the other one It can be inserted into the T-shaped groove of the first coupling device. -A space having an opening facing the key groove when inserted into the first coupling device and having a shear key loosely fitted therein is provided. (3) The shear key is: When the second coupling device is inserted into the first coupling device, the shear key is loosely fitted in the void of the second coupling device that is arranged to face the installation position of the key groove. . -The wedge driven into the second coupling device pushes it out of the built-in position of the second coupling device and engages with the keyway.

[0010]

The precast floor slab joining device of the present invention is provided with the following means. (1) Each of the T-shaped grooves provided in the two first joining devices secured to the joining side surfaces of the adjacent precast slabs. ,
By inserting both sides of the H-shaped second coupling device, the tensile force and the horizontal shearing force between the adjacent precast floor slabs are transmitted. (2) The shear key built in the second coupling device is extended by inserting a wedge and engaged with the key groove of the first coupling device, so that the vertical direction between the adjacent precast floor slabs is increased. Transmits shear force. (3) The compressive force between adjacent precast floor slabs is
Of the first coupling device and the second coupling device. Can act.

As described above, according to the joining device for the precast floor slab of the present invention, the one in which the first joining device is fixed to the joining side portion of the precast floor slab in advance is carried to the work site and installed side by side. , Inserting both sides of the second coupling device into the T-shaped groove of the first coupling device fixed to each of the adjacent precast floor slabs, and driving the wedge into the second coupling device,
Adjacent precast floor slabs can be mechanically coupled to each other. As a result, the on-site connection work is significantly reduced, and the problems associated with the on-site work can be eliminated. In addition, since no formwork or scaffolding for joining is required, the work can be shortened and safety can be secured.

Furthermore, when replacing the precast floor slab, the shearing key can be removed from the key groove to remove the second coupling device from the first coupling device, and the coupling surface of the precast floor slab can be removed. Since no work is required, the construction period can be shortened without damaging the surrounding environment. Also,
The work of passing the PC steel wire through the sheath embedded in the precast floor slab becomes unnecessary, and no special device for joining the precast floor slab such as a device for tensioning the PC steel wire is required.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A precast floor slab connecting apparatus of the present invention will be described below with reference to the drawings. 1 to 3 show a first embodiment of a joining device for precast floor slabs of the present invention. Figure 1
2 is a perspective view showing an overall configuration of a precast floor slab joining apparatus according to this embodiment, FIG. 2 is a plan view of a joining portion of the precast floor slab joined by the joining apparatus of FIG. 1, and FIG. 3 is an arrow of FIG. FIG.

As shown in FIG. 1, recesses 2 are formed facing each other on each side surface of a precast floor slab 1 that is adjacently joined. A fitting metal fitting A3 as a first joining device, the outer shape of which is formed into a substantially rectangular parallelepiped shape, is inserted into both side surfaces 4, 4 and a rear side surface 5 of the concave portion, and the front side surface 6
Are fixed to the precast floor slab 1 on the same surface as the bonding surface 8. As shown in FIG. 3, this fixing is performed by welding the dowels 13 to the side surfaces 4, 4 and the rear side surface 5 of the fittings A, 3 so that the fittings A3 are precast when the precast floor slab 1 is molded. It can be done by placing the precast floor slab 1 at the installation position and placing concrete on the precast floor slab 1.

Of course, the first connecting device may be integrally formed of the same material as the precast floor slab 1 without using the metal fitting A3 and metal, but in this case, the first connecting device installation portion is compressed. Since a large load such as force and tensile force is concentrated, it is necessary to reinforce it more strongly than other parts. Also,
It is desirable that the height of the coupling fitting A3 be the same as the plate thickness of the precast floor slab 1.

The fittings A and 3 are provided with an opening 9 opening to the front side surface 6 and an engaging portion 10 provided behind the opening in parallel with the front side surface 6 and having a width larger than the opening width of the opening 9. But,
It is provided so as to penetrate in the height direction (the thickness direction of the precast floor slab 01). The middle portion of the opening 9 in the height direction is expanded to form a key groove 11. The opening 9 and the engaging portion 10 are T-shaped when viewed from above, and the opening 9 and the engaging portion 10 are collectively referred to as a T-shaped groove 12 hereinafter.

Next, reference numeral 15 is a coupling fitting B as a second coupling device. The coupling fitting B15 is composed of a holding portion 16 inserted into the engaging portion 10 of the coupling fitting A3, and a connecting portion 17 that connects the two holding portions 16 and is inserted into the opening 9 and is viewed from above. In this case, an H-shaped outer shape is formed. A wedge hole 18 penetrating in the height direction is formed in the connecting portion 17, and a space 19 for accommodating a shear key 20 described later is formed in the middle in the height direction.
As shown in FIG. 3, this space 19 is provided so as to face the key groove 11 provided in the fitting A3 when the fitting B15 is inserted into the T-shaped groove 12 of the fitting A3.

Reference numeral 20 is a shear key, which is formed in a pair, is loosely inserted in the space 19 of the coupling fitting B15, and is pressed by the wedge 21 inserted from the wedge hole 18 to the outside from the connecting portion 17. It is possible to project to.

With the above-described structure, the precast floor slab joining apparatus of the present embodiment has the precast floor slabs 1 placed so that the joining metal fittings A3 are butted against each other when the side surfaces of adjacent precast slabs 1 are joined together. T-shaped groove 12
Then, the H-shaped coupling fitting B15 is inserted. At this time, the shear key 20 is housed in the coupling fitting B15.
After inserting the fitting B15, the wedge 21 is driven into the wedge hole 18, whereby the shear key 20 is fitted into the shear key 11 provided on the fitting A3.

That is, as shown in FIG. 3 (A), the shear key 20 is in a state of being incorporated in the coupling fitting B15,
The keyway 1 of the fitting A3 into which the fitting B15 is fitted by driving the wedge 21 as shown in FIG.
The shear key 20 is inserted into the device 1. In this way, the mutual force transmission of the precast floor slabs 1 whose side surfaces are coupled to each other transmits the compressive force by abutting the front side surfaces of the coupling fittings A3. Further, by inserting the H-shaped coupling metal fitting B15 into the T-shaped groove 6 of the coupling metal fitting A3, the tensile force and the shearing force in the horizontal plane can be transmitted. Furthermore, by inserting the shear key 20 into the key groove 11 of the coupling metal fitting A3, it is possible to transmit the vertical shearing force and prevent the coupling metal fitting B15 from coming off the coupling metal fitting A3. When replacing the precast floor slab 1, the wedge 21 can be pulled out and the shear key 20 can be removed from the key groove 11 for easy disassembly.

Next, FIGS. 4 and 5 are views showing the second to third embodiments of the joining device for the precast floor slab of the present invention.
FIG. 4 is a plan view of the second embodiment, and FIG. 5 is a plan view of the third embodiment. As shown in FIG. 4, the T-shaped groove 12a penetrating the first coupling device is formed in each coupling fitting A, 15a.
Two may be provided in parallel with each other, and the side portions of the H-shaped second coupling device may be respectively inserted and fitted. That is, the H-shaped fitting B is rotated by 90 ° to be used in an I-shape, and two T-shaped grooves 12a are formed in each of the adjacent precast floor slabs 1 on both sides which are enlarged and tapered. You may make it couple | bond and insert in each.

Further, as shown in FIG. 5, the T-shaped groove 12b provided penetrating the first coupling device 36 does not have to be one step, and the second and third T-shaped grooves 12b are formed on the T-shaped groove 12b. V-shaped groove 1
2c and 12d may be formed. That is,
When the root of the turbine rotor blade is fitted to the rotor disk, the shape can be similar to that of a Christmas tree formed on the root of the turbine rotor blade. This has the disadvantage of increasing the manufacturing cost of the fittings A, 3b and the fittings B, 15b, but the holding power of the fittings A, B is much better than that of the first embodiment, and the adjacent fittings are adjacent. There is an advantage that the side of the precast floor slab can be firmly fixed.

[0023]

As described above, according to the joining device for precast floor slabs of the present invention, the following effects are brought about by the constitutions set forth in the claims. (1) Since the side surfaces of adjacent precast slabs are joined by mechanical joining, there is no need to place concrete or mortar on site, and the work is completed only from the top surface of the precast slab to be joined. There is no need for a scaffold to be provided around the joint, especially on the lower surface of the precast floor slab, and it is possible to reduce costs, shorten the construction period, and ensure safety. (2) It is possible to replace the precast floor slab without removing the concrete by simply attaching and detaching the fittings, and it is possible to reduce the cost and the construction period without deteriorating the surrounding environment.

[Brief description of drawings]

FIG. 1 is an overall perspective view showing a first embodiment of a joining device for a precast floor slab of the present invention.

FIG. 2 is a plan view in which adjacent precast floor slabs are joined by the joining device of FIG.

FIG. 3 is a diagram showing a view AA of FIG.
3A is a cross-sectional view before wedge driving, and FIG. 3B is a cross-sectional view after wedge driving.

FIG. 4 is a plan view in which adjacent precast floor slabs are joined by a joining device as a second embodiment of the present invention.

FIG. 5 shows a coupling device according to a third embodiment of the present invention,
It is a top view which combined the adjacent precast floor slabs.

FIG. 6 is a cross-sectional view showing an example of joining of conventional adjacent precast floor slabs.

FIG. 7 is a cross-sectional view showing another example of connection of conventional adjacent precast floor slabs.

[Explanation of symbols]

1 Precast floor slab 2 Recesses formed on the precast floor slab 3, 3a, 3b First coupling device (coupling metal A) 4 Side surface of coupling metal A 5 Rear side surface of coupling metal A 6 Front side surface of coupling metal A 7 8 Precast Connection side of floor slab 9 Opening of coupling metal A 10 Engagement portion of coupling metal A 11 Key groove 12 T-shaped groove 13 Gibel 14 15a, 15b, 15c Second coupling device (coupling metal B) 16 Holding of coupling metal Part 17 Connection part of connecting fitting 18 Wedge hole 19 Void of connecting fitting B 20 Shear key 21 Wedge

Claims (1)

[Claims] 1. A joining device for precast floor slabs, which joins the side surfaces of adjacent precast floor slabs to form a floor surface, in the recesses formed respectively facing the joining side surfaces of the adjacent precast floor slabs. The T-shaped groove having both sides and the rear side inserted and fixed to the precast floor slab with the front side flush with the connecting side, and having the opening to the front side formed with the key groove as the leg A first connecting device provided penetrating in the thickness direction of the precast floor slab and one side portion inserted into each of the T-shaped grooves provided opposite to each other;
When an H-shaped second coupling device for connecting both side surfaces of the precast floor slabs adjacent to each other and a first coupling device incorporated in the second coupling device, the first coupling device and the second coupling device are coupled by inserting a wedge. And a shear key fitted into the key groove to fix the first and second coupling devices.