JPH09177070A - Method and device for placing of steel bar cage for deep foundation - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and device for placing a steel bar cage economically and effectively, with which operators are secured with safe and good working environment. SOLUTION: A derric-shaped provisional frame 2 is erected in the on-the- ground part of the mouth of a deep foundation pit 1. At the pit mouth, a plurality of chain wheel winches 3 capable of simultaneous operation are installed, and a support ring 4 is held suspendedly. On the ground, vertical steel bars 12 to constitute a cage 11 are attached one by one to this support ring 4, and hoops 13 are welded to the periphery of these vertical bars 12 one by one. In this manner the cage 11 is completed from below with necessary rigidity ensured, and the completed part is hung down together with the support ring 4 bit by bit into the deep foundation pit 1 with the aid of the chain wheel winch 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of constructing a rebar cage in a process of constructing a deep foundation pile or a shaft by a deep foundation method and a construction device used for the method.

[0002]

2. Description of the Related Art As a method of assembling a rebar cage for deep foundations, a person enters the shaft of the deep foundation to construct a rebar work scaffold, suspends the rebar from the aboveground portion, and manually assembles the rebar. Is common.

Under the condition that the vertical shaft of the deep foundation has a relatively small diameter and the large crane truck can approach the deep foundation under construction, after the reinforcing cage is assembled horizontally on the ground, the reinforcing cage is constructed by the large crane truck. In some cases, it may be lifted or suspended in the shaft.

[0004]

The method of suspending a reinforced basket with a large crane car is limited in its application range due to restrictions on space and the like, as well as economic problems due to the size of the deep foundation. .

On the other hand, the method of manually assembling the rebar cage in the vertical shaft has many problems in terms of ensuring worker safety, working environment, and working efficiency.

[0006] That is, regarding the safety of the worker,
The deep foundation work is vertical work, and all the work processes are in a vertical relationship, so there is a high risk of workers and objects falling or falling, and it is difficult to install a safety protection facility.

Further, regarding the work environment, when the work position is at the bottom of the shaft, the environment is more adverse than the ground work in terms of ventilation, lighting, temperature, humidity, pneumoconiosis damage and the like.

The present invention solves the problems relating to the assembly and installation of the rebar cage in the conventional deep foundation work, and is economical and efficient, and the safety of the worker and the good working environment can be secured. The purpose of the present invention is to provide a cage building method and a cage building apparatus.

[0009]

The method for constructing the deep foundation rebar cage according to the present invention is a support for supporting from below a temporary mount and a rebar cage to be assembled on the ground section at the ground section above the entrance of the shaft for deep foundation. A ring and a suspension device that supports this support ring so that it can be raised and lowered with respect to a temporary mount are installed, and the vertical bars (main bars) that make up the reinforcing bar cage are sequentially installed on the support ring. The surrounding stirrup (hoop streak) is connected to the vertical stirrup, the rigidity of the rebar cage is secured from below, and the support ring is suspended from the bottom by the suspension device to assemble it on the ground. It is characterized by installing a rebar cage in the vertical shaft.

As the suspension device, there are, for example, a chain block, a chain wheel winch, and the like. A plurality of suspension devices arranged around the wellhead can be moved up and down by synchronously operating the support ring while keeping the support ring horizontal. In addition,
The hanging device may be a center hole jack, a winch, or the like.

In some cases, the deep foundation may have a length of several tens m to a hundred and several tens m, and the supporting of only the lower end may easily deform the reinforcing bar and the reinforcing bar cage.

According to claim 2 of the present application, in addition to the support at the lower support ring position, the case of suspending and supporting the intermediate portion in the depth direction of the reinforcing bar basket is also limited. Further, claim 3 limits the case where the rebar cage is assembled and hoisted while the support ring is being relocated upward as the hoisting work of the rebar cage is advanced.

In this way, it is possible to deal with the case where the reinforcing bar and the reinforcing bar cage are long.

When the number of rebar cages is two or more, the outer cage may be constructed first, and then the inner cage may be constructed.

The construction device for the deep foundation rebar cage of the present invention is as follows:
With regard to the device used for the above-mentioned construction method, a temporary stand on the ground part of the well entrance shaft of the deep foundation shaft, a support ring that supports the reinforcing bar cage assembled from the bottom part from below, and a support ring are moved up and down with respect to the temporary mount. It is characterized in that it comprises a suspending device that supports it as much as possible.

According to a fifth aspect of the present invention, the case where the suspension device comprises a plurality of chain wheel winches that can be operated in synchronization with each other is limited.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGS. 1 to 3 show an embodiment of a method and apparatus for constructing a deep foundation rebar basket according to the present invention.

The erection device comprises a temporary tower 2 in the shape of a tower constructed on the ground above the pit of a deep foundation shaft 1, a plurality of chain wheel winches 3 arranged so as to surround the pit, and a chain hole winch 3 for horizontal movement. And a support ring 4 which is suspended and supported by the.

In the figure, 5 is a liner plate installed on the wall surface of the deep foundation shaft 1, 6 is a ring steel stand for a chain hole winch, and 8 is a vertical bar stopper for fixing the vertical bar 12 to the support ring 4. A metal fitting, 9 is a chucking device for connecting the chain 7 of the chain hole winch 3 to the support ring 4, and 10 is a lower workbench on the ground.

An example of the construction procedure using the above apparatus is as follows.

A temporary pedestal 2 is constructed on the aboveground part of the well foundation shaft 1 where the excavation is completed, and a plurality of chain wheel winches 3 as suspension devices are installed on the aboveground part.

A reinforcing bar cage support ring 4 is installed, and is suspended and supported by a chain wheel winch 3 via a chain 7. In addition, in this example, a plurality of chain wheel winches 3 arranged so as to surround the aboveground part of the shaft of the vertical shaft are used as a suspension device, and the supporting ring 4 supporting the rebar cage 11 is horizontally operated by operating them in synchronization. It is possible to move up and down while maintaining.

The vertical bars 12 as main bars are hung one by one with a crane or the like and attached to the support ring 4. For stability, a ring may be provided on the upper part of the temporary pedestal 2 to support the reinforcing bar at two or more upper and lower positions.

The stirrup 13 is arranged around the vertical streak 12 arranged in a tubular shape, and is joined by welding or the like.

A portion of the reinforcing bar cage 11 that is secured by connecting the stirrups 13 is settled into the deep pit 1 by operating the chain wheel winch 3 as a suspension device.

Subsequently, in the upper part, the vertical stripes 12
Arrange the stirrups 13 around and repeat the work of.
When the deep foundation becomes deeper, the vertical streak 12 is added to the upper side. If the reinforcing bar cage 11 is long and the displacement at the lower end is large, the support ring 4 at the bottom is replaced with the middle reinforcing bar 1.

For this refilling work, for example, after inserting an auxiliary horizontal member for temporary support under the stirrup 13 at the already joined portion, the load of the suspension device is released and the load of the rebar cage 11 is released. It is possible to carry out refilling by depositing it on an auxiliary horizontal member, transferring the lower support ring 4 to the middle part, mounting it on the rebar cage 11, and transferring the load to the chain wheel winch 3 on the ground again. After the transfer of the load, the auxiliary horizontal member below the stirrup 13 is removed.

When the refilling is completed, the work of is repeated again.

After the rebar cage 11 has been assembled and installed, the chain wheel winch 3, the support ring 4 and the temporary mount 2 are removed.

[0030]

[Effects of the Invention] Economical and efficient construction is possible with relatively simple and small equipment, there are few restrictions due to space, etc., and the applicable range is wide.

Since the work for assembling the rebar cages can be performed on the above-ground portion while the rebar cages are successively settled in the shaft, it is possible to secure the safety of the operator and a good working environment.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an outline of a method of installing a deep reinforcement bar basket of the present invention.

FIG. 2 is a perspective view showing an example of a reinforcing bar attaching method in a supporting ring portion and a supporting method using a chain wheel winch.

FIG. 3 is a perspective view showing a state in which a reinforcing bar basket is assembled on the ground using a temporary mount.

[Explanation of symbols]

1 ... Deep foundation shaft, 2 ... Temporary stand, 3 ... Chain hole winch, 4 ... Support ring, 5 ... Liner plate, 6 ... Chain hole winch ring steel stand, 7 ... Chain, 8
... Vertical bar stoppers, 9 ... Chucking device, 10 ... Lower workbench, 11 ... Reinforcing bar cage, 12 ... Vertical bar, 13 ... Belt bar,

Claims (5)

[Claims] 1. A temporary pedestal at the aboveground part of the pit of the deep foundation shaft,
A support ring that supports the rebar cage that is being assembled on the ground from below and a suspension device that supports the support ring so that the support ring can move up and down with respect to the temporary frame are installed. After installing streaks, after that, the stirrups surrounding the vertical stirrup are connected to the vertical stirrup, and the rigidity of the rebar cage is secured from below, and the supporting ring is used to secure the support ring in the deep foundation shaft. A method of building a deep-reinforcing bar cage, which is characterized by installing the rebar cage assembled on the ground in the shaft by hanging it up to the ground. 2. The method of constructing a rebar cage for deep foundation according to claim 1, wherein in addition to the support at the support ring position, an intermediate portion in the depth direction of the rebar cage is also suspended and supported. 3. With the progress of the operation of hanging the rebar cage,
3. The method for constructing a deep foundation rebar cage according to claim 1, wherein the rebar cage is assembled and hung while the support ring is refilled upward. 4. A temporary pedestal on the aboveground part of the shaft of the shaft for deep foundation,
An apparatus for constructing a rebar cage for deep foundations, comprising: a support ring that supports a rebar cage that is being assembled on the ground from below and a suspension device that supports the support ring so that the support ring can move up and down with respect to a temporary frame. 5. The apparatus for constructing a rebar cage for deep foundation according to claim 4, wherein the suspension device comprises a plurality of chain wheel winches that can be operated in synchronization with each other.