JPH059931A - Joining method for underground continuous wall - Google Patents

Abstract

PURPOSE:To prevent horizontal reinforcements from being elastically separated outside from each other to improve durability of a junction in a joining method of an underground continuous wall in which a reinforcement joint of the end of a reinforcement cage of the preceding element and a reinforcement joint of the end of a reinforcement cage of the following element are arranged and connected by a lap joint, by eliminating horizontal gaps between horizontal reinforcements of both the reinforcement joints. CONSTITUTION:Horizontal reinforcements 8a of a reinforcement joint 8 of a reinforcement cage 9 on the following element 2 side are bent by tensing their tips or the vicinity of the tips by linear member 15 so that their tips move nearer to each other against elasticity of the horizontal reinforcements 8a. The reinforcement joint 8 between which the width is narrowed in such a manner, on the following element 2 side is inserted between horizontal reinforcements 5a of a reinforcement joint 5. Thereafter, the linear member 15 is cut off to make straight the right and left horizontal reinforcements 8a of the reinforcement joint 8 on the following element 2 side by elasticity and to bring the horizontal reinforcements near the horizontal reinforcements 5a of the reinforcements joint 5 on the preceding element 1 side.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for joining underground continuous walls with horizontal reinforcing bar joints.

[0002]

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 fabricate a reinforced concrete panel in the ground, and the concrete panel is used as a unit element and sequentially connected. Then, conventionally, when the continuous underground wall is used as an earthquake-resistant wall of a basement floor, each panel is connected by a crossbar joint construction method or the like for transmitting in-plane force.

Further, as a joint construction method, a horizontal streak lap joint construction method may be adopted as an inter-wall joint construction method capable of transmitting in-plane and out-of-plane forces. This construction method is shown in FIGS. 5 and 6. In the preceding element 1, the reinforcing bar joint 5 is projected from the partition plate 3 of the reinforcing bar basket 4 in which the partition plate 3 as the iron plate form is incorporated at the rear end. . This rebar joint 5 is also a rebar basket 4
Similarly, the horizontal streaks 5a and the vertical streaks 5b are combined.
The concrete placed on the side of the preceding element 1 is stopped by this partition plate 3. The trailing element 2 is provided with a reinforcing bar basket 9 having a reinforcing bar joint 8 at its tip. The rebar joint 8 is narrow so that it can be inserted into the rebar joint 5, and is composed of a combination of the horizontal bar 8a and the vertical bar 8b as in the rebar joint 5, but the horizontal bar 8a is bent and the mutual It is configured to narrow the gap.

After the concrete 6 of the preceding element 1 is poured, the reinforcing bar basket 4 of the trailing element 2 is placed in the excavation hole 10 and, although not shown, the concrete of the trailing element 2 is poured. The reinforced rebar joint 5 and the rebar joint 8 are wrapped to make a joint.

[0005]

In the conventional joint joint structure shown in FIGS. 5 and 6, the horizontal bars 5a and 8a, which are joint bars, are lapped at intervals with respect to each other for joining the reinforcing bar joints. Therefore, when an out-of-plane bending stress β is applied, these horizontal streaks on the pulling side bounce outward, and as shown by α in Fig. 5, cracks occur in the concrete on the trailing element 2 side and the yield strength decreases. There is a risk that

The splitting fracture by the horizontal streaks 5a and 8a is extremely fragile, and the splitting fracture cannot be prevented even if the amount of the horizontal streaks is increased. In addition, the splitting fracture resistance is positively correlated with the overlapping length of the horizontal streak, and even if the leading panel side horizontal strip and the trailing panel side horizontal strip are separated vertically Split fracture occurs at.

The object of the present invention is to eliminate the disadvantages of the prior art and eliminate the horizontal gap between the horizontal bars of the reinforcing bar joints in the lap joint in advance so that the horizontal bars can be separated from each other and flipped outward. It is to provide a method for joining underground continuous walls, which can prevent such a situation and improve the yield strength of the joint.

[0008]

In order to achieve the above object, the present invention inserts a horizontal bar of a reinforcing bar joint of a trailing element of a reinforcing element of a trailing element between horizontal bars of a reinforcing bar joint of a leading element of a preceding element and stacks them. In the method of joining underground continuous walls to be joined with joints, the horizontal bars on the left and right of the reinforcing bar joint of the reinforcing element cage on the trailing element side are tensioned with a linear member at the tip or in the vicinity thereof to resist the elasticity of the horizontal bars. After bending the tips so that they are close to each other, and inserting the narrow reinforcing bar joints on the trailing element side between the horizontal bars of the reinforcing bar joints on the preceding element side, cutting the linear member Align the left and right horizontal bars of the reinforcing bar joint on the row element side by elasticity so that they are close to the horizontal bars of the reinforcing bar joint on the preceding element side, and the linear member has one end connected to the other end of the number line connected to the horizontal bar. The body is set and this ring is Polymerization was pierced longitudinally by the bar, it is an Abstract that separates the ring member mutually disconnected by pulling out the rod member upward.

[0009]

According to the present invention as set forth in claim 1, when the horizontal lap joint portion receives an out-of-plane force, 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 will be separated in the horizontal direction. And make a move. According to the present invention, after inserting the reinforcing bar joint of the trailing element side between the horizontal bars of the reinforcing bar joint of the preceding element side, the linear member is cut to form the left and right horizontal bars of the reinforcing bar joint of the trailing element side. Since it is made straight by elasticity and is brought close to the horizontal bar of the reinforcing bar joint on the side of the preceding element, it is possible to eliminate a gap between the horizontal bars of the reinforcing bar joints in the horizontal direction in advance to form a single bar-shaped lap joint. As a result, an increase in split fracture resistance can be expected, and abrupt crack development can be prevented even when the joint portion receives out-of-plane bending stress.

According to the second aspect of the present invention, in addition to the above action, the easiness of cutting the linear member is taken into consideration, and the linear members are vertically spaced by the number of steps of the horizontal streaks. Even if they are arranged side by side, the plurality of linear members can be cut at once by pulling out the rods in the upward direction.

[0011]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a cross-sectional plan view showing one embodiment of a method for joining underground continuous walls of the present invention, and FIGS.
The same components as those of the above are designated by the same reference numerals.

On the side of the preceding element 1, the partition plate 3 of the reinforcing bar basket 4 incorporating the partition plate 3 as a formwork.
First, the reinforcing bar joint 5 configured by the combination of the horizontal bar 5a and the vertical bar 5b is projected. The horizontal bar 5a is an extension of the horizontal bar of the reinforcing bar basket 4, and the interval between the left and right horizontal bars 5a is a straight line that maintains the same width as the horizontal bar of the reinforcing bar basket 4.

The partition plate 3 is provided at both ends with flange plates 3a in a direction orthogonal to the partition plate 3 with a required width.
Try to make a shape. Since the partition plate 3 is equal to the width of the drill hole, the flange plate 3a is in contact with the wall of the drill hole,
It is located parallel to the borehole wall. Also, the flange plate 3
The shear reinforcing bar 22 may be provided so as to pass through the partition plate 3 from a.

On the other hand, on the trailing element 2 side, a reinforcing bar basket 9 having a reinforcing bar joint 8 composed of a combination of horizontal bars 8a and vertical bars 8b at its tip is provided. The left and right horizontal streaks 8a maintain a straight shape as an extension of the horizontal streaks of the reinforcing bar basket 9 when nothing is restrained. Further, the interval between the left and right horizontal streaks 8a is
It is almost the same as the interval of a.

According to the present invention, in the reinforcing bar joint 8 of the reinforcing bar basket 9 on the trailing element 2 side, the horizontal bars 8a on the left and right are tensioned by the linear member 15 at or near the tips of the horizontal bars 8a.
The tips are bent so as to approach each other against the elasticity of.
It should be noted that at the reinforcing bar basket 9 side or at the root of the reinforcing bar joint 8, the split preventing bar 16 is hung between the left and right horizontal bars and fixedly connected by welding or the like, and even if the horizontal bar 8a is bent, a certain interval is maintained. Be able to hold.

Further, a split preventing bar 17 can be provided in the reinforcing bar joint 8. In this case, the split preventing bar 17 is provided with a channel-shaped guide 18 so as to be slidable without being fixed to the horizontal bar 8a. It should only be placed through.

The linear member 15 may be a cord or a wire, which may be cut later with a knife or the like. In this embodiment, one end of the wire 19 is attached to the horizontal line 8a. body
It is a combination of those provided with 20. The horizontal streaks 8a are bent to a position where the ring bodies 20 are overlapped with each other and attracted to each other, and the overlapping ring bodies 20 are vertically penetrated by a rod member 21 such as round steel. With this configuration, the multi-stage linear members in the vertical direction of the horizontal stripe 8a
All 15 can be locked at the center with a single rod 21.

On the side of the preceding element 1, the reinforcing bar basket 4 with the partition plate 3 is hung in the excavation hole, and the concrete 6 is cast to form the preceding panel. The cast concrete is stopped by the partition plate 3. After the concrete 6 of the preceding element 1 is placed, the reinforcing bar basket 9 of the trailing element 2 is arranged in the excavation hole 10. As described above, the reinforcing bar joint 8 of the reinforcing bar basket 9 has a horizontal bar 8a having a linear shape. Since the member 15 is strained and narrowed, it can be easily inserted between the horizontal bars 5a of the reinforcing bar joint 5.

By thus grasping the upper end of the bar 21 on the ground and pulling it upward, the overlapping ring members 20 can be separated and the linear members 15 can be cut. Since the tension in the linear member 15 is eliminated, the left and right horizontal streaks 8a return to a straight shape by elasticity and are joined to the horizontal streaks 5a of the reinforcing bar joint 5 on the side of the preceding element 1 as shown in FIG.

As described above, the horizontal streaks 5a and the horizontal streaks 8a are made as close as possible to each other to form a lap joint, and although not shown, concrete is placed on the side of the following element 2 to form the following panel. For example, the reinforcing bar joint 5 and the reinforcing bar joint 8 which are overlapped are joined.

When the horizontal lap joint portion receives an out-of-plane force, the horizontal bar 5a of the reinforcing bar joint 5 of the preceding element 1 and the horizontal bar 8a of the reinforcing bar joint 8 of the trailing element 2 move so as to separate from each other in the horizontal direction. However, in the present invention, since the horizontal gap between the horizontal streaks 5a and 8a is eliminated in advance to form a single lap joint close to a rod shape, it becomes difficult to separate, and an increase in split fracture resistance can be expected.

Further, when the horizontal streaks 5a and the horizontal streaks 8a move so as to separate from each other in the horizontal direction, the bending moment of the partition plate 3, which is H-shaped as a whole, acts to cause the flange plate 3a at the end of the partition plate 3 to move. It acts as a restraint by restraining the joint from the outside. As a result, it can be expected that the split fracture proof stress will increase.

As another embodiment, a reinforcing member 11 may be attached to the horizontal bar 5a of the reinforcing bar joint 5 on the side of the preceding element 1. As shown in FIG. 4, the reinforcing member 11 is formed by attaching elliptical hoop muscles 13 to a vertical axis member 12 in a trapezoidal shape with a vertical interval, and the vertical axis material 12 penetrates the inside of the hoop muscle 13. , Weld it close to the end and fix it by welding. Also, vertical axis material 12
In order to reduce the weight of the reinforcing member 11 as a whole, it is desirable to use a pipe to make the inside hollow.

When the reinforcing member 11 is attached to the horizontal bar 5a, the vertical axis member 12 is arranged in a direction orthogonal to the horizontal bar 5a,
The hoop muscle 13 is oriented so that its lateral direction is parallel to the longitudinal direction of the horizontal muscle 5a. The vertical axis member 12 is rotatably attached to the reinforcing bar joint 5 with a wire or the like.

After placing the concrete 6 of the preceding element 1, the reinforcing bar basket 9 of the trailing element 2 is arranged in the excavation groove 10, and the horizontal bar 8a of the reinforcing bar joint 8 of the reinforcing bar basket 9 is reinforced as described above. The lap joint is formed by overlapping the horizontal streak 5a of the joint 5, and if the upper end of the vertical axis member 12 is grasped and turned in this way, the hoop streak 13 rotates about the vertical axis member 12 As shown in FIG. 3, the hoop muscles 13 are arranged so as to straddle the horizontal muscles 5a and 8a and intersect each other in the orthogonal direction.
The vertical position of the hoop muscle 13 is the horizontal muscle 5a and the horizontal muscle 8a.
The vertical streaks 5b and 8b are not provided in the reinforcing bar joint 5 or the reinforcing bar joint 8 for the horizontally long intervals of the hoop reinforcing bars 13 so that they are displaced between the horizontal bars 5a and the horizontal bars 8a in the upper and lower stages. Keep a space around which the hoop muscle 13 can wrap around.

The hoop muscle 13 acts as a width stop muscle, and the ordinate member 12 may be filled with mortar.

[0027]

As described above, the method of joining underground continuous walls of the present invention is an underground continuation in which the reinforcing bar joint at the end of the reinforcing bar of the preceding element and the reinforcing bar joint at the end of the reinforcing bar of the trailing element are arranged in a lap joint. In the wall joining method, by eliminating the horizontal gap between the horizontal bars of the reinforcing bar joints in advance, it is possible to prevent the horizontal bars from separating and popping outward, and it is possible to improve the yield strength of the joint. is there.

[Brief description of drawings]

FIG. 1 is a cross-sectional plan view before joining showing an embodiment of a joining method for underground continuous walls of the present invention.

FIG. 2 is a horizontal cross-sectional plan view showing an embodiment of a method for joining underground continuous walls of the present invention after completion of reinforcement.

FIG. 3 is a cross-sectional plan view after joining showing one embodiment of the method for joining underground continuous walls of the present invention.

FIG. 4 is a front view of a reinforcing member.

FIG. 5 is a cross-sectional plan view showing a conventional example.

FIG. 6 is a longitudinal side surface showing a conventional example.

[Explanation of symbols]

1 ... Leading element 2 ... Trailing element 3 ... Partition plate 3a ... Flange plate 4 ... Reinforcing bar basket 4a ... Drawing part 5 ... Reinforcing bar joint 5a ... Horizontal bar 5b ... Vertical stripes 6 ... Concrete 8 ... Reinforcing bar joint 8a ... horizontal streak 8b ... vertical streak 9 ... Rebar cage 10 ... Drilling hole 11 ... Reinforcement member 12 ... Vertical axis material 13 ... hoop muscle 15… Linear member 16,17… Split prevention muscle 18… Guide 19… Track 20 ... Ring 21 ... Bar 22 ... Shear reinforcement

Claims (2)

[Claims] 1. A method for joining an underground continuous wall in which a horizontal bar of a reinforcing bar joint of a rear element of a trailing element is inserted between horizontal bars of a reinforcing bar joint of a leading element of a preceding element, and is joined by a lap joint. The horizontal bars on the left and right of the reinforcing bar joint of the element side reinforcing bar basket are strained by a linear member at the tip or in the vicinity thereof to bend the tips against each other against the elasticity of the horizontal bar. After inserting the narrow rebar joint on the trailing element side between the horizontal bars of the rebar joint on the preceding element side, cut the linear member to elastically resize the left and right horizontal bars of the rebar joint on the trailing element side. A method for joining underground continuous walls, which is characterized in that a straight shape is brought close to the horizontal bar of the reinforcing bar joint on the side of the preceding element. 2. A linear member is provided with a ring body at the other end of a wire which is connected to a horizontal streak at one end, and the ring body is polymerized and vertically penetrated by a rod member, and the rod member is pulled out upward. The method for joining underground continuous walls according to claim 1, wherein the ring bodies are separated from each other to be in a cut state.