JP2619214B2 - Hardware for lifting concrete pavement slab and method of assembling the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metal fitting for lifting a concrete pavement slab, which lifts a concrete pavement sunk unevenly, and a method of assembling the same.

[0002]

2. Description of the Related Art Recently, prestressed concrete slabs have been used as pavement slabs at airports. On the other hand, airports are often built in landfills at sea, and measures for uneven settlement due to land subsidence have become a major technical problem compared to before. As a countermeasure against uneven settlement of the concrete paving slab, it is conceivable to bury a reaction force device for lifting the concrete paving slab in advance on the underside of the paving slab. Alternatively, the settlement may occur at an unexpected location, so that it has to be installed in an unnecessarily wide area, resulting in a high cost. Furthermore, there is a possibility that rust may occur on the concrete slab lifting hardware that is buried in advance, and foreign materials may be clogged inside due to the use of the road surface, making it impossible to use it when it is actually needed. was there.

[0003] From such a viewpoint, when subsidence occurs, an appropriate position and number of working holes are penetrated in the subsidence area above and below the concrete paving slab, and the concrete paving slab is lifted using the working holes. Technology is being developed. (Japanese Unexamined Patent Publication No.
-318605, JP-A-2-289703). In this case, if a large hole is made as a working hole, it becomes inappropriate as a pavement plate at an airport. Therefore, a large hole cannot be made, and the hole is limited to a hole having a minimum diameter that allows use of a jack for pulling.

[0004] A conventional concrete slab lifting fixture is to form a space by drilling a work hole in a necessary place of the concrete slab, excavating a peripheral portion under the work hole, and dividing the space into a plurality of concrete pieces. Insert the plate support plate, assemble it on the flange of the auxiliary cylinder in the space, screw the cylinder body into the screw part of the auxiliary cylinder, sandwich the concrete plate support plate between the lower end of the cylinder body and the upper surface of the flange, and Integrate.
As a result, the cylinder main body is mounted in the working hole of the concrete slab, and the concrete slab support plate projects to the lower peripheral edge of the working hole. And let the jack contact the cylinder body dynamically,
When the base body is lifted by causing the roadbed to take a reaction force, the concrete slab support plate is pressed against the lower surface of the concrete slab and lifted.

Next, a concrete plate lifting process using a concrete pavement plate lifting fixture will be described with reference to FIGS. As shown in FIG. 6 (a), the amount of settlement of the concrete paving slab 1 is measured, and then, as shown in FIG. 6 (b), working holes 2 are formed in the settlement area. Next, as shown in FIG. 6 (c), the roadbed under the working hole 2 is excavated to form a space 3 under the working hole, and concrete is poured into the bottom as shown in FIG. 6 (d). To form a reaction plate 4. FIG.
As shown in (e), the space 3 below the working hole on the reaction plate 4
And in the working hole 2, a metal fitting 10 for lifting a concrete pavement slab.
Is set. The concrete pavement lifting hardware 10 is
Conventionally, as shown in FIG. 5, it is composed of a sleeve 17, a concrete plate support plate 15, and a pull-up cylinder 11. The pulling cylinder 11 has a male screw 12 and a flange 13 at a lower end thereof. The male screw 12 is the female screw 1 of the sleeve 17
8 The outer diameter of the flange 13 is slightly smaller than that of the working hole 2 so that the working hole can be inserted. A pin 14 is implanted on the upper surface of the flange 13. The concrete slab support plate 15 contacts the lower surface of the concrete pavement slab,
When the concrete paving slab lifting metal fitting 10 is pulled up with a jack, the concrete paving slab is lifted.
The concrete plate support plate 15 is formed by dividing a circular plate into a large number of sectors so that the concrete plate support plate 15 can be inserted into the work hole space 3 below the concrete paving slab through the work hole 2. The concrete slab support plate 15 has an inner diameter fitted to the screw portion of the pull-up cylinder 11 so that the pin 14 can be inserted into the pin hole 16. When the female screw 18 of the sleeve 17 is screwed into the male screw of the pull-up cylinder 11, the concrete plate support plate 15 is sandwiched between the upper surface of the flange 13 and the lower surface of the sleeve 17. The concrete plate support plate 15 is brought into contact with the lower surface of the concrete paving slab, and the sleeve 17 is jacked up. As shown in FIG. 7 (e), the concrete paving slab lifting metal fitting 10 is positioned in the working hole space 3 at a position where the concrete slab support plate 15 contacts the lower end of the concrete paving slab. The ram chair of the jack 40 is screwed into the female screw 18 at the upper end of the sleeve 17 on the concrete pavement lifting hardware 10 as shown in FIG.

A reaction force support plate 45 is placed on the reaction force plate 4. As shown in FIG. 7 (g), when the ram of the jack 40 is brought into contact with the reaction force support plate 45 and the ram of the jack 40 is pushed out, the ram chair is raised by the reaction force of the reaction force support plate 45, and the concrete pavement is formed. The concrete paving slab 1 is lifted via the plate lifting hardware 10. Then, after lifting to the desired height, the lock nut previously inserted into the sleeve 17 is brought into contact with the reaction force support plate 45,
The jack is removed leaving the concrete paving slab lifting hardware 10, the lock nut and the reaction force support plate 45. After that,
As shown in FIG. 7 (h), the backing material 50 is filled in the space below the lifted concrete paving slab 1, and the concrete paving slab lifting operation is completed.

[0007]

In the above technique, the area of the upper surface of the flange 13 of the pulling cylinder 11 is limited. That is, the outer diameter of the flange 13 is smaller than the inner diameter of the working hole 2, and the outer diameter of the male screw 12 is restricted by the inner diameter of the sleeve. Therefore,
The supporting force for supporting the concrete slab support plate 15 is inevitably a barely numerical value in the design calculation. For this reason, it became clear that it might not be possible to bear the load that the concrete slab support plate 15 can support for the following reasons. (A) When the jack pulls up the sleeve 17, the screw of the sleeve 17 acts in the pulling-up direction. Therefore, the clamping force with which the lower end surface of the sleeve 17 supports the concrete plate support plate 15 is reduced. This is the fate of the screw mechanism where there is a small gap between the male and female threads. (B) For this reason, the contact surface between the concrete slab support plate 15 and the upper surface of the flange 13 is inclined, causing a localized concentrated load, and the concentrated load portion is partially sagged and deformed. (C) Once the deformation occurs, the supporting area of the upper surface of the flange 13 is small, and the concrete plate support plate 15 has a large outer diameter, so that a large moment is generated and the deformation of the deformed portion proceeds. (D) Since this deformation does not return, the jack pulling force is reduced and does not rise further.

Under the circumstances described above, the pulling force pulled up by the 25-ton jack does not rise more than about 7 tons, and the sleeve 17 comes off from the upper surface of the concrete paving slab 1. The present invention provides a concrete paving slab lifting bracket and a method for assembling the same, which solves such problems.

[0009]

SUMMARY OF THE INVENTION The present invention is directed to a concrete paving slab lifting hardware which solves the above problems,
(A) A sleeve having a female screw for mounting a lifting jack and fitted inside a working hole of a concrete paving slab, and (b) a pull-up screwed into the sleeve and having a lower flange having a smaller diameter than the working hole at the lower end thereof. A tube, (c) a flange outer peripheral connecting member which is fitted to the lower flange of the pull-up tube and has a plurality of divided circumferences, and (d) is sandwiched between the upper surface of the pull-up tube lower flange and the sleeve; A concrete paving slab lifting bracket comprising a fan-shaped divided concrete slab support plate for supporting a lower surface of the concrete paving slab. The point different from the prior art of the present invention is the above point (c), in that the flange outer peripheral connecting member is attached to the outer diameter of the flange by the following method.

That is, in the method of the present invention, when assembling the metal fitting for lifting the concrete paving slab of the present invention in the working hole formed in the concrete paving slab, the lifting cylinder is turned upside down and mounted in the space below the working hole. Then, insert the flange outer peripheral member sequentially into the space below the working hole, mount and align it on the outer periphery of the flange of the pull-up cylinder, temporarily attach it, weld the flange and the flange additional member, and then pull up The cylinder is turned upside down to the normal position, the concrete plate support plate is inserted into the space below the work hole and positioned on the upper surface of the flange, and then the sleeve is inserted into the work hole and screwed into the pull-up tube to screw the support plate. The method for assembling a metal fitting for lifting a concrete pavement slab, comprising:

[0011]

With the metal fitting for lifting a concrete paving slab of the present invention, the lower flange of the pulling cylinder is enlarged, so that the support plate is sufficiently supported and the jack pulling force is transmitted to the paving slab. The concrete pavement lifting hardware can be attached to the lifting cylinder flange in the space below the working hole by the assembling process of the present invention.

[0012]

FIG. 1 is an exploded view of a concrete paving slab lifting hardware according to an embodiment. The metal fitting for lifting a concrete pavement slab of the embodiment includes a conventional sleeve 17, a concrete slab support plate 15, a pull-up cylinder 11, and a flange outer peripheral connecting member 10.
0 is provided. This flange outer peripheral connecting member 100 is
It is integrally attached to the outer periphery of the flange 13 of the pulling cylinder 11 by welding. This flange outer peripheral connecting member 100 is
It is divided into a plurality of pieces so that the work hole can be inserted into the space 3 below the concrete paving slab from the work hole.
The dimension 1 corresponds to the outer diameter of the flange 13. Also,
A pin 14 is implanted on the upper surface thereof, and a concrete plate support plate 15 is provided with a hole 16 through which the pin penetrates.

FIG. 2 is an explanatory view showing a method for assembling the metal fitting for lifting a concrete pavement slab according to an embodiment of the present invention. Pull cylinder 1
1 is turned upside down and inserted into the space 3 below the working hole 2 through the working hole 2. Then, the divided flange outer peripheral connecting member 1
00 is inserted through the work hole 2 into the space 3 below the work hole.
Then, the divided flange outer peripheral connecting member 100 is temporarily attached to the outer periphery of the flange 13 of the pulling cylinder 11. In this temporary mounting, the outer peripheral flange member 100 is fitted to the outer diameter of the flange 13 using the magnet 111, and the flange and the outer peripheral flange member are spot-welded. The welding rod 110 is inserted from the working hole 2 and welded to the inner periphery of 100. In advance, the outer circumference of the flange 13 and the outer circumference of the flange
A groove for welding is provided on the inner periphery of 0.

Then, the pulling cylinder 11 is turned upside down to the normal position, and the concrete slab support plate 15 is inserted into the working hole in the same manner as in the prior art shown in FIG. Insert the sleeve 17 into the working hole,
1 and fasten and clamp the concrete plate support plate 15. The flange 13 is provided on the outer periphery of the flange
00 is attached, and since the area of the upper surface is large, it is supported with a large supporting force. Therefore, the concrete paving slab 1 can be pulled up without reducing the jack pulling force as in the related art.

FIG. 3 shows a process of lifting the concrete paving slab 1 and the ram chair 41 of the jack 40 is
7 shows a process in which the ram 42 takes up a reaction force on the reaction force support plate 45 and pulls up the sleeve 17. The pull-up cylinder 11 is screwed onto the lower end of the sleeve 17 and the sleeve 17
And the pulling cylinder 11 firmly clamp and hold the concrete paving plate support plate 15, and these are integrated with each other. The concrete paving plate support plate 15 abuts on the lower surface of the concrete paving plate 1, and the concrete paving plate Raise 1 When the paving board 1 is pulled up, the nut 44 is screwed downward by the handle 43, and the nut 44 is
5 to remove the jack.

FIG. 4 shows a state in which this operation is completed, the concrete paving slab 1 is pulled up, and the lower space created by filling the cement grout and then the sleeve 17 is covered with a lid 60. The nut 44 is supported by a support plate 45.
The concrete pavement lifting hardware 10 can be reused by removing the lid 60 if necessary.

[0017]

According to the present invention, the jack pulling force can be applied to the lower surface of the pavement slab without causing the fixed portion at the center of the concrete slab support plate to be flat, and uneven sunk of the concrete pavement slab can be prevented. It can be easily modified. Also, there is an excellent effect that the supporting force of the concrete paving slab lifting hardware can be secured by a simple assembling method.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view showing a concrete paving slab lifting hardware of an embodiment.

FIG. 2 is an explanatory view of a method of assembling a metal fitting for lifting a concrete pavement slab according to an embodiment.

FIG. 3 is an explanatory view of the use of a metal fitting for lifting a concrete pavement slab according to an embodiment.

FIG. 4 is a vertical sectional view of a metal fitting for lifting a concrete pavement slab according to an embodiment.

FIG. 5 is an exploded perspective view of a conventional concrete paving slab lifting hardware.

FIG. 6 is a process diagram illustrating a paving slab lifting operation.

FIG. 7 is a process diagram illustrating a paving slab lifting operation.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 concrete paving plate 2 working hole 3 working hole lower space 4 reaction plate 10 concrete paving plate lifting bracket 11 pulling cylinder 12 male screw 13 flange 14 pin 15 concrete plate support plate 16 hole 17 sleeve 18 female screw 40 jack 41 ram chair 42 Ram 43 Handle 44 Nut 45 Reaction force support plate 50 Backing material 60 Cover 100 Flange extension member 101 Inner diameter 110 Welding rod 111 Magnet

 ──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-1-318605 (JP, A) JP-A-2-289703 (JP, A) JP-B 5-57362 (JP, B2)

Claims (2)

(57) [Claims] 1. A sleeve having a female screw for mounting a lifting jack, which is internally fitted in a working hole of a concrete paving slab, a male screw which is screwed into the sleeve, and a lower flange having a smaller diameter at the lower end than the working hole. A lifting cylinder, a flange outer peripheral connecting member attached to an outer periphery of the lower flange, and a plurality of fan-shaped support plates sandwiched between an upper surface of the lower flange of the lifting cylinder and a lower surface of the sleeve and abutting on a lower surface of the concrete paving slab. A metal fitting for lifting a concrete pavement slab. 2. When assembling the metal fitting for lifting a concrete paving slab according to claim 1 in a working hole formed in the concrete paving slab, the lifting cylinder is turned upside down and inserted into a space below the working hole. The flange outer peripheral member is inserted into the space below the working hole and temporarily attached to the outer periphery of the flange of the pull-up tube, the flange and the flange outer peripheral member are welded to each other, and then the pull-up tube is turned over to correct Position, the fan-shaped support plate is inserted into the space below the work hole and positioned on the upper surface of the flange, then the sleeve is inserted into the work hole, screwed into the pull-up cylinder, and the support plate is clamped and clamped. Method of assembling a metal fitting for lifting a concrete pavement slab.