JPH05148834A - Junction structure of underground continuous well - Google Patents

Abstract

PURPOSE:To improve the yield strength of a junction section by devising the title structure so that the and section of the external horizontal reinforcement of a joint section is not sprung out. CONSTITUTION:In the junction structure of an underground continuous wall, in which the reinforced joint of the cage end of a succeeding element is bar- arranged outside the reinforced joint of the cage end of a preceding element by a lap joint, inward opened hooks 11 are mounted at the left and right ends of a parting plate 3 incorporated to the cage 4 of the preceding element 1. Outward opened hooks 12 installed at the front ends of the horizontal reinforcements 8a of the reinforced joints 8 of the succeeding element 2 are engaged with the inward opened hooks 11 of the parting plate 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a joint structure of a continuous underground wall by a horizontal reinforcing bar joint.

[0002]

2. Description of the Related Art As is well known for underground continuous walls, a horizontally long drill hole is formed in the ground, and a reinforcing bar basket is inserted into the drill hole.
Next, concrete is poured into the excavation hole to produce a reinforced concrete panel in the ground, and the reinforced concrete panel is used as a unit element and sequentially connected. The horizontal stirrup lap joint method is adopted as the joint method for connecting the panels to each other as the wall-to-wall joint method capable of transmitting in-plane and out-of-plane forces.

This construction method is shown in FIG. 14, in which the leading element 1 has a reinforcing bar joint 4 projecting from the partition plate 3 of a reinforcing bar basket 4 having a partition plate 3 as an iron plate form at the rear end. .. This rebar joint 5 is also a horizontal bar 5a like the rebar basket 4.
And a vertical stripe 5b. The concrete placed on the side of the preceding element 1 is stopped by this partition plate 3.
The trailing element 2 has a reinforcing bar basket 9 provided with a reinforcing bar joint 8 at the tip thereof. The reinforcing bar joint 8 has a narrow width so that it can be inserted into the reinforcing bar joint 5, and is composed of a combination of horizontal bars 8a and vertical bars 8b as in the reinforcing bar joint 5.
Are bent and the distance between them is narrowed.

After placing the concrete 6 of the preceding element 1, the reinforcing bar basket 4 of the trailing element 2 is placed in the excavation groove, and although not shown, the concrete of the trailing element 2 is placed. Reinforcing bar joint 5 and reinforcing bar joint 8
Is joined in.

[0005]

According to the conventional joint joining structure shown in FIG. 14, the horizontal bar 5 is used for joining the reinforcing bar joints.
Since only a and 8a are wrapped, when the out-of-plane bending stress β is received, these horizontal streaks on the tensile side bounce outward, and as shown in α in Fig. 14, the concrete on the trailing element 2 side is cracked. It may occur and the yield strength may decrease.

The object of the present invention is to solve the disadvantages of the above-mentioned conventional example, devise the end of the outer horizontal streak of the joint so that it does not project, and improve the yield strength of the joint. It is to provide a joint structure of walls.

[0007]

In order to achieve the above-mentioned object, the present invention is a ground for arranging a reinforcing bar joint of a trailing element reinforcing bar basket end with a lap joint outside a reinforcing bar joint of a preceding element reinforcing bar basket end. In the joining structure of the middle continuous wall, hooks that open inward are provided at the left and right ends of the partition plate that is incorporated into the reinforcing bar basket of the preceding element, and hooks that open outward are provided at the ends of the horizontal bars of the reinforcing bar joint of the following element. The gist of the present invention is to engage with a hook that opens inward of the partition plate.

[0008]

According to the present invention, the tip of the horizontal bar of the reinforcing bar joint of the trailing element is locked to the partition plate incorporated in the reinforcing bar basket of the preceding element via the hook, and even when the horizontal lap joint section receives an out-of-plane force. It doesn't bounce outside. As a result, the horizontal bar of the reinforcing bar joint of the preceding element and the horizontal bar of the reinforcing bar joint of the following element do not tend to separate in the horizontal direction, and it becomes a rigid joint, and an increase in splitting fracture resistance can be expected. It is possible to prevent the rapid development of cracks even if the portion receives an out-of-plane bending stress.

[0009]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is an explanatory view showing a first embodiment of a joint structure of an underground continuous wall of the present invention, FIG. 2 is a cross-sectional plan view showing the details thereof, and the same components as those of FIG. 14 showing the conventional example are referred to the same. The reference numerals are attached.

As in the prior art example, the leading element 1 side is a combination of horizontal bars 5a and vertical bars 5b in the reinforcing bar basket 4 in which a partition plate 3 as an iron plate frame is incorporated at the rear end thereof. The reinforcing bar joint 5 constituted by is projected. 22 in the figure
Is a vertical flat bar arranged at the tip of the horizontal line 5a.

Further, a reinforcing bar basket 9 having a reinforcing bar joint 8 at its tip is disposed on the trailing element 2 side. The reinforcing bar joint 8 is wide so that the reinforcing bar joint 5 can be inserted therein and, like the reinforcing bar joint 5, is composed of a combination of horizontal bars 8a and vertical bars 8b.

According to the present invention, the hooks 11 that open inwardly at the left and right ends of the partition plate 3 incorporated in the reinforcing bar basket 4 of the preceding element 1.
On the other hand, a hook 12 that opens outward is provided at the tip of the horizontal bar 8a of the reinforcing bar joint 8 of the trailing element 2. As shown in detail in FIG. 4, these hooks 11 and 12 are made of a vertical angle material such as L-shaped steel and are attached to the tip of the partition plate 3 and the horizontal streaks 8a by welding. Further, window holes 14 may be appropriately formed in the hooks 11 and 12 as angle members so as not to obstruct the surrounding of the concrete placed on the trailing element 2 side.

Reference numeral 13 in the figure is a width stop bar. In the figure, reference numeral 15 denotes a cast-in-concrete preventive sheet provided on the partition plate 3 on the side of the preceding element 1. The concrete preventive sheet 15 is joined to the L-shaped receiving member 16 provided at the end edge of the partition plate 3 and this. It is provided by sandwiching and fixing the end portion with a pressing plate 17 stopped by a bolt 18.

After pouring the concrete of the preceding element 1, the reinforcing bar basket 4 of the trailing element 2 is arranged in the excavation groove. At this time, the tip of the horizontal bar 8a of the reinforcing bar joint 8 of the trailing element 2 is arranged. The outwardly opening hook 12 provided on the above is engaged with the inwardly opening hook 11 of the partition plate 3. After this, although not shown, if concrete of the trailing element 2 is placed, the rebar joint 5 and the rebar joint 8 to be wrapped are joined, and the end of the horizontal bar 8a is locked to the partition plate 3. To be done.

In actual construction, in order to engage the hook 12 with the hook 11, the tip of the horizontal streak 8a must be as close to the partition plate 3 as possible. Therefore, the horizontal line 8a
A horizontal adjustment unit 19 is provided in the middle of this so that the horizontal movement of the horizontal line 8a can be absorbed by this adjustment unit 19. 5 to 7 show the details of the adjusting portion 19, in which the horizontal streak 8a is cut to provide an interval corresponding to the length required for the adjustment, and the reinforcing bar 20 is added to this interval. Further, one side of the reinforcing bar 20 is tightly connected to the reinforcing bar joint 8 and the other side is inserted into the guide to be free.

In the example shown in FIG. 5, a hat-shaped guide 21a as shown in FIG. 8 is provided on the width stop bar 13, and the reinforcing bar 20 is inserted into the guide bar 21a, and the example shown in FIG. 6 is as shown in FIG. This is a case where the pipe-shaped guide 21b is provided on the width stop bar 13 and the reinforcing bar 20 is inserted therein. Further, the example of FIG. 7 is a case where a pipe type guide 21c and a hoop type guide 21d as shown in FIGS. 10 to 13 are provided on the horizontal streak 8a, and the reinforcing bar 20 is inserted into the guides 21c and 21d. , Reinforcement bar 20 is horizontal bar 8a
Are lined up and down.

In the examples shown in FIGS. 1 and 2, the horizontal bar 5a of the reinforcing bar joint 5 projecting from the partition plate 3 is the same as the width of the horizontal bar of the reinforcing bar basket 4 and is straight, but as another embodiment, As shown in FIG. 3, the width of the horizontal reinforcements 5a may be narrower than the width of the horizontal reinforcements of the reinforcing bar basket 4 by squeezing the front and rear of the partition plate 3. With this configuration, the horizontal reinforcement 8a of the reinforcing bar joint 8 can be arranged outside the horizontal reinforcement 5a without increasing the width of the horizontal reinforcement 8a.

[0018]

As described above, in the structure for connecting underground continuous walls of the present invention, the reinforcing bar joint at the end of the reinforcing bar of the trailing element is arranged by a lap joint outside the reinforcing bar joint at the end of the reinforcing bar of the preceding element. In the joint structure of the underground continuous wall to be installed, it is possible to improve the proof stress of the joint by devising so that the end of the outer horizontal bar of the joint does not protrude. The horizontal bar and the horizontal bar of the reinforcing bar joint of the trailing element do not try to separate in the horizontal direction,
A rigid joint can be expected to increase the fracture fracture resistance, and it is possible to prevent rapid crack development even when the joint portion receives out-of-plane bending stress.

[Brief description of drawings]

FIG. 1 is an explanatory view showing a first embodiment of a joint structure for a continuous underground wall of the present invention.

FIG. 2 is a cross-sectional plan view showing the details of the first embodiment of the joint structure of the underground wall of the present invention.

FIG. 3 is an explanatory view in a cross-sectional plan view showing details of a second embodiment of the joint structure of the underground wall of the present invention.

FIG. 4 is a perspective view of a main part of a joint structure for a continuous underground wall according to the present invention.

FIG. 5 is a plan view showing an example of an adjusting portion provided in the middle of a horizontal line of a trailing element used in the joint structure for an underground continuous wall of the present invention.

FIG. 6 is a plan view showing another example of the adjusting portion provided in the middle of the horizontal line of the trailing element used in the joint structure of the underground continuous wall of the present invention.

FIG. 7 is a plan view showing still another example of the adjusting portion provided in the middle of the horizontal line of the trailing element used in the joint structure for the underground wall of the present invention.

FIG. 8 is a front view showing a first example of a reinforcing reinforcing bar guide.

FIG. 9 is a front view showing a second example of a reinforcing reinforcing bar guide.

FIG. 10 is a front view showing a third example of a reinforcing reinforcing bar guide.

FIG. 11 is a side view showing a third example of the reinforcing reinforcing bar guide.

FIG. 12 is a front view showing a fourth example of a reinforcing reinforcing bar guide.

FIG. 13 is a side view showing a fourth example of the reinforcing reinforcing bar guide.

FIG. 14 is a cross-sectional plan view showing a conventional example.

[Explanation of symbols]

 1 ... Leading element 2 ... Trailing element 3 ... Partition plate 4 ... Reinforcing bar basket 5 ... Reinforcing bar joint 5a ... Horizontal bar 5b ... Vertical bar 6 ... Concrete 8 ... Reinforcing bar joint 8a ... Horizontal bar 8b ... Vertical bar 9 ... Rebar bar 11 ... Hook 12 ... Hook 13 ... Width stop bar 14 ... Window hole 15 ... Concrete prevention sheet 16 ... Receiving plate 17 ... Retaining plate 18 ... Bolt 19 ... Adjusting part 20 ... Reinforcing bar 21a-21d ... Guide 22 ... Flat bar

Claims (3)

[Claims] 1. In a joint structure of a continuous underground wall in which a reinforcing bar joint of a trailing element of a reinforcing bar basket is arranged by a lap joint outside a reinforcing bar joint of a preceding element of a reinforcing bar basket, a reinforcing bar of a preceding element is connected to a reinforcing bar basket of a preceding element. Hooks that open inward are provided at the left and right ends of the partition plate to be incorporated, and hooks that open outward that are provided at the ends of the horizontal bars of the reinforcing bar joint of the trailing element are engaged with the hooks that open inward of the partition plate. A joint structure of continuous underground walls. 2. The joint structure for a continuous underground wall according to claim 1, wherein the hook is formed of a vertical angle member. 3. The underground continuous wall according to claim 1, wherein a horizontal adjusting portion is provided by cutting a horizontal portion of the horizontal line of the trailing element, and a reinforcing bar having one end free by a guide is added to this part. Junction structure.