JPH0718154B2 - Rebar basket - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of use] The present invention relates to a reinforcing bar cage used for construction of cast-in-place concrete piles.

[Conventional technology]

When using cast-in-place concrete piles in the construction of a building with a basement, dig hole 1 from the ground with an excavator as shown in Figs. Then, the concrete 3 is filled to a required depth leaving the basement part, and the back part is backfilled 4 on the upper part, and then the basement part 5 is cut.

In this way, the hole drilling from the surface of the ground before the root cutting 5 is performed in consideration of the difficulty of setting on the ground after the root cutting 5 because the excavator for the pile is large. is there.

In addition, the rebar cage 2 has holes 1 to prevent it from rising.
Insert a hole having the same length as the depth of the hole into the hole 1, but leave some parts above the concrete 3 into the root cutting 5
Cut and remove with.

[Problems to be Solved by the Invention]

As described above, the upper part of the hole 1 corresponding to the basement and the upper part of the rebar cage 2 are not necessary anymore, and therefore it is desirable that the number is as small as possible.

However, there is no pile construction technology in which only the upper part of the unnecessary part has a small diameter.

There is also a diameter-expanded cast-in-place pile that expands the bottom of the pile as a special pile.

Various excavators for diameter expansion have been proposed for construction of such diameter expansion piles,
Deep bottom drilling is possible. However, a normal rebar cage may be used, or as shown in JP-A-58-29917 and JP-A-58-520, a reinforcing bar in which only the lower end of the outer car is expanded like an umbrella. There was only a basket.

Therefore, the rebar cage does not reach the upper position around the expanded diameter portion of the drill hole, which is disadvantageous to the bending moment.

For example, if the ground moves horizontally due to an earthquake,
If a bending shearing force is generated above the pile expanded at the boundary with the soft ground, it cannot withstand this.

The object of the present invention is to eliminate the disadvantages of the above-mentioned conventional example, insert the bottom into a hole with an expanded diameter, and since the main bar can be expanded over the entire length of this expanded portion, it is economical for cast-in-place concrete piles having a basement, (EN) It is possible to provide a reinforcing bar cage which enables a rational and safe construction and which can increase the tip frictional force of a pile on which a pulling force acts.

[Means for Solving the Problems]

In order to achieve the above-mentioned object, the present invention comprises an inner car and an outer car into which the lower part of the inner car enters, and the outer car replaces the hoop reinforcement around the longitudinal rebar which is the main reinforcement when expanded. A flexible rope made of high-strength fiber is connected so that the size of the expanded diameter can be adjusted, and an arm is provided at least on the upper and lower parts of the outer car via a hinge part, and the other end of the arm is hinged. Is connected to the inner car through a portion, and an arm that bends outward is provided at the lower end of the vertical reinforcing bar that constitutes the outer car through the hinge portion, and the flat bar is coupled to the other end of the arm through the hinge portion. Therefore, the gist is to provide a flat bar on the bottom of the outer car.

[Action]

According to the invention, the enlarged longitudinal reinforcing bar in the outer car will catch this as the main bar. Therefore,
It is important to secure the position of this main bar, and in order to quickly and easily reach such a main bar to a predetermined position in the expanded hole regardless of whether the expanded hole is large or small, it is necessary to use a high A flexible rope such as a strength fiber was used.

This flexible rope can change the space between the adjacent vertical bars quickly and easily by stretching or loosening it, and the length can be adjusted easily compared to the rod-shaped member, Since it is possible to secure the position of the main bar in advance, the workability is excellent.

This operation is such that when the inner car is hung to be inserted into the hole, the outer car hangs slightly downward relative to the inner car and hangs, and the arms are slanted, so The distance between them is narrow and the outer basket is folded.
In this state, it can be easily inserted through a drill hole having a small diameter.

Then, the flat bar of the suspended outer car surely lands horizontally on the bottom of the hole, and then when the bottom positions of the inner car and the outer car get closer to each other, the arms are also raised horizontally and the diameter expansion Push the outer basket sideways at the bottom of the hole.

At this time, an arm is provided on at least the upper and lower parts of the outer car via the hinge part, and the other end of this arm is connected to the inner car via the hinge part. While maintaining the vertical state over the upper part, the reinforcing bar can be arranged as a main bar over the entire length of the expanded diameter portion of the hole bottom.

〔Example〕

 Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a side view showing one embodiment of the reinforcing bar cage of the present invention,
The rebar cage of the present invention comprises an inner cage 6 and an outer cage 2
It has a heavy basket structure.

Of these, the inner basket 6 may be the same as a normal rebar cage,
The vertical reinforcing bars 8 were connected by circular hoop bars 9. 10 in the figure
Shows a flat bar.

The outer car 7 is one in which the lower part of the inner car 6 is inserted, and instead of connecting the vertical reinforcing bar 8'with the circular hoop bar 9, a flexible rope 11 made of high-strength fiber such as carbon fiber or aramid fiber is connected. did.

The connection between the flexible rope 11 and the vertical reinforcing bar 8'is the binding wire 12
You can conclude with.

Further, the outer car 7 has the flat bar 10 only at the bottom part, but the flat bar 10 and the lower end of the vertical reinforcing bar 8'are connected by the arm 14 via the hinge part 13, and by the existence of the hinge part 13, The arm 14 is disposed between the flat bar 10 and the lower end of the vertical reinforcing bar 8'so as to be bent outward.

In addition, the vertical rebar 8'of the outer car 7 and the vertical rebar 8 of the inner car 6
Is the arm 15 at an appropriate interval (2 to 3 m) in the vertical direction.
The arm 15 is also connected via the hinge portion 13.

FIGS. 2 and 3 show the details of the arms 14 and 15 and the hinge portion 13, and adopt a pin joint structure in which the ends of the plate-like flange body are superposed on each other and are joined by the pin 16.
In addition, the end of the flat flange body is, for example, an arm.
When a reinforcing bar is used for 14, it is provided on a holder 17 into which the reinforcing bar end or the vertical reinforcing bar 8'line is screwed.

Hinge part 13 where the vertical reinforcing bar 8 of the inner car 6 and the arm 15 join
The holder 17 'into which the vertical reinforcing bar 8 is inserted is provided with the flat plate-shaped flange body, and the flat plate-shaped flange body at the end of the arm 15 is connected to the holder 17' by the stacking pin 16.

Next, the usage will be described.

As shown in FIG. 5, a hole 1'where the lower part 1a expands is excavated by using a diameter expanding excavator, and the reinforcing bar car of the present invention is hung in the hole 1 '.

At the time of insertion into the hole 1 ', the inner car 6 is slightly displaced (about 20 cm) upward from the outer car 7, and the arm 15 connecting the inner car 6 and the outer car 7 is inclined, Further, since the arm 14 is also vertical and the flexible rope 11 is loosened, the outer car 7 is in a folded state, so to speak, with a small interval between the vertical reinforcing bars 8 '.

In this state, the rebar cage can be inserted from the upper portion 1b of the hole 1'which does not expand.

When the rebar cage reaches the bottom of the hole 1'as shown in FIG. 6 and the bottom positions of the inner cage 6 and the outer cage 7 approach each other, the arm 14 is pantographed outward as shown in FIG. Then, the arm 15 is also raised in a horizontal state, the loose flexible rope 11 is stretched, and the outer car 7 is pushed and expanded laterally by the lower portion 1a of the expanded diameter hole 1 '.

After setting the reinforcing steel cage in the hole 1'in this way, the tremie pipe 18 is inserted into the inner cage 6 and the concrete 3 is poured.

When the upper part 1b of the hole 1'is used as the basement part, the concrete 3 is placed only on the expanded lower part 1a as described above,
The part 1b is backfilled and the basement is cut off.

Further, in the case of a diameter-expanded pile, concrete 3 may be filled in all the holes 1'to form a pile.

In the above embodiment, the outer cage 7 has a flat bar 10 at the bottom.
The flat bar 10 and the lower end of the vertical reinforcing bar 8'are connected by the arm 14 via the hinge portion 13. However, in some cases, the flat bar 10 may be omitted, and the arm 14 may be unnecessary. .

〔The invention's effect〕

In recent years, buildings planned on the waterfront or the like have to have basements because the height is limited. Moreover, since the supporting ground is deep, you will have a pile under the basement.

As described above, the reinforcing bar cage of the present invention has a bottom portion inserted into a hole having an enlarged diameter, and since the main bar can be pushed over the entire length of the enlarged diameter portion, an increase in the tip frictional force of the pile on which the pull-out force acts can be increased. Is what you get.

And if the present invention is used, the pile in the basement part is not necessary, so the basement part of the pile can be made as small as possible, the amount of drilling and the amount of backfilled soil are reduced, and the earth retaining at the time of root cutting work is stopped. There is less falling inside the wall, which increases safety.

In addition, it is important to secure the position of the main bar, and in order to quickly and easily keep the main bar at a predetermined position in the expanded hole regardless of the diameter of the expanded hole, a high-strength fiber is used instead of the hoop bar. A flexible rope, such as, for example, can be used to quickly or easily change the distance between adjacent longitudinal reinforcing bars by stretching or loosening it. Since the position can be secured in advance, the workability is good.

[Brief description of drawings]

FIG. 1 is a side view of a reinforcing bar car according to an embodiment of the present invention in a folded state, FIG. 2 is a side view of a main part of the same, FIG. 3 is a front view of the same, and FIG. 4 is a side view in an expanded state. FIG. 5, FIG. 5 to FIG. 7 are side views showing a usage state, and FIG. 8 to FIG. 10 are side views showing a conventional example. 1,1 ′ …… hole, 1a …… bottom 1b …… upper, 2 …… reinforcing cage 3 …… concrete, 4 …… backfilling 5 …… root cutting 6 …… inner cage, 7 …… outer cage 8, 8 '... vertical reinforcing bar, 9 ... hoop bar 10 ... flat bar, 11 ... flexible rope 12 ... binding wire, 13 ... hinge part 14,15 ... arm, 16 ... pin 17, 17 '…… Holder, 18 …… Tremy tube

Claims (1)

[Claims] 1. An inner basket and an outer basket into which the lower part of the inner basket is inserted. The outer basket is a high-strength fiber which replaces the hoop reinforcement around the longitudinal reinforcing bar that is the main reinforcement when expanded. The flexible cage is connected so that the size of the enlarged diameter can be adjusted, and at least the upper and lower parts of the outer car are provided with arms via the hinge part, and the other end of the arm is internally connected via the hinge part. An arm that is connected to the car and that folds outward through a hinge is provided at the lower end of the vertical reinforcing bar that forms the outer car, and the other end of the arm is connected to the flat bar through the hinge to provide the bottom of the outer car. Reinforcing bar cage characterized by having a flat bar on the bottom.