JPS6117635A - Protector for connected reinforcing bar in underground continuous wall - Google Patents

Abstract

PURPOSE:To prevent the grinding loss of connected reinforcing bars and the intrusion of gravel when excavating adjacent units by a method in which the connected reinforcing bars in an unit underground wall after the placement of concrete are covered with a covering material, and a freely rocking gravel removing bottom plate is provided to the covering material on the bottom of the connected portion. CONSTITUTION:A protector 1 is composed of a trough-shaped covering material 2 of a U-shaped cross section to cover connected reinforcing bars 19 projected from an underground continuous wall, legs 9 provided to the base side of the lower end of the covering material 2, a cable 12 whose one end is pivotally supported on the lower end of the leg 9 and whose free end is tensed or loosened from the ground surface, and a bottom plate 10 movable in a rocking manner between the rising position along the leg 9 and the inclined position in contact with the connecting face of the underground continuous wall. The protector 1 is erectly set on the surrounding of the connected reinforcing bars 19 of the underground continuous wall to protect the connected reinforcing bars from an excavator to form holes for adjacent underground continuous walls. Damage to the connected reinforcing bars can be prevented, and gravel, etc., on the bottom of the connected portion can be removed out.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a protection device for joint reinforcing bars in an underground continuous wall.

The length of an underground continuous wall is limited depending on various ground conditions, construction conditions, etc. Therefore, the wall must be composed of multiple unit walls, and there are no connections between adjacent unit walls. part occurs.

Conventionally, as a method of joining underground continuous walls, an assembly is inserted into an excavated trench for a unit wall, with a reinforcing bar cage fixed to one side of a partition plate and a large number of joining reinforcing bars protruding from the other side. After installation, a support material such as gravel is placed in the space on the side of the joint reinforcing bars, and then concrete is poured in the space on the side of the reinforcing bars, and a groove hole is excavated for the unit wall adjacent to the concrete hardening machine. The support material is removed, and an assembly similar to the assembly is inserted and installed in this groove, and the reinforcing bar cage and the joining reinforcing bars protruding from the concrete-cast unit wall are overlapped. There is a construction method. However, according to this construction method, although supporting materials such as gravel can absorb the lateral pressure that acts on the partition plates during concrete pouring, the supporting materials are also removed at the same time when excavating the grooves for the adjacent unit walls. As a result, there is a risk that the joint reinforcing bars may be damaged by the excavator, and there is also a drawback that support materials remain below the joint reinforcing bars and cannot be completely removed, making it impossible to fully expect the joint to become an integral structure. .

This invention eliminates the drawbacks of the conventional construction method described above, eliminates the risk of breakage by protecting the joint reinforcing bars, prevents support material from remaining under the joint reinforcing bars, and prevents adjacent unit walls. An object of the present invention is to provide a protection device for joint reinforcing bars in an underground continuous wall that can reliably join bodies together.

That is, the joint reinforcing bar protection device according to the present invention has a gutter shape having a pair of side surfaces spaced apart from each other and a back surface between the two side surfaces, and a large number of openings are formed in the both side surfaces and the back surface. At the lower end of the vertically oriented cover, a leg is provided vertically at the back surface, and the leg has a width larger than the distance between the side surfaces and a distance from the leg to the front end of the side surface. The proximal end of a bottom plate having a longer length than the base plate is pivotally mounted to be vertically rotatable, and the other end of the cable body, one end of which is located above the cover, is fixed to the free end of this bottom plate, and the bottom plate is The cord is characterized in that it can be rotated between a position in which it stands up along the leg member and a position in which it is inclined toward the front end of the side part as the cord is tensed and relaxed, respectively. .

The embodiments shown in the drawings will be described below.

As shown in FIGS. 1 to 3, the protective device 1 has a vertical cover 2.
The covering part 2 is in the form of a gutter having a pair of side parts S, S spaced apart from each other and a back part B between both side parts 8. It is formed by joining a large number of horizontal steel members 4 in the height direction of the vertical steel members 3 of the book so as to form a U-shape when viewed from above. The cover part 2 has the above-mentioned structure, and has a frame structure as a whole, so that a large number of rectangular openings 5 with four sides of the vertical steel members 3 and the horizontal steel members 4t are formed in the side parts S, S and the back part. It is formed in B. A reinforcing material 6 may be joined between the diagonal corners of the opening 5 if necessary. A hanging piece 7 is provided on the uppermost horizontal steel material 4, and a flange 8 is provided at the front end of each horizontal steel material 4.

A pair of legs 9 are vertically provided at the lower end of the cover 2 at the back side B, and the legs 9 are provided by extending the vertical steel member 3 on the back side B side downward. There is.

The base end of the bottom plate lO is pivotally attached to the leg part 9 via a hinge 11 so as to be rotatable in the vertical direction, and the bottom plate 10 is connected to the side parts S, S.
The width is also large, and the distance from the leg portion 9 to the front end of the side surface portion S, that is, the front end of the horizontal steel member 4 is also large. The lower end of a wire 12 is fixed to the free end of the bottom plate 10, and this wire 12 is supported by a pulley 13 provided inside the transverse steel member 4 and extends upward inside the cover 2, with the upper end of the wire 12 being supported by a pulley 13 provided inside the horizontal steel member 4. protrudes upward. Therefore, by tensioning the wire 12 upward, the bottom plate 10 rotates clockwise in FIG. The side surface portion S is tilted toward the front end side. Legs 91
/( is provided with a leaf spring 14 which is pressed by the bottom plate 10 when it is erected, and the bottom plate 10 is provided with a large number of through holes 15 which are large enough to not allow gravel or the like to pass through.

A construction method using such a protection device 1 will be explained with reference to FIGS. 4 to 7.

First, a slot 16 for a unit wall of a predetermined length is excavated with an excavator, etc., and then reinforcing bars [118] are fixed to one side of the partition iron plate 17, and a large number of joining reinforcing bars 19 are attached from the other side in a predetermined manner. Insert and install the protruding assembly 20 into the slot 16 (a pair of guides 22 for guiding the flange 8 of the protection device 1 are fixed to the other side of the cover 4A).

Next, hang a wire etc. on the hanging piece 7 of the protection device l, and
The protection device 1 is inserted and installed in the space on the side of the joint reinforcing bars 19 in 6 with the flange 8 along the guide 22 using a crane or the like, and the joint reinforcing bars 19 are covered by the covering part 2 (the fourth
Figure B).

When inserting the protective device 1, pull the wire 12 to make the bottom plate 10 stand up, so that the bottom plate 10 does not collide with the joint reinforcing bars 19, and when the legs 5 reach the bottom of the slot 16, remove the wire 12. Loosen the bottom plate 10 from the original leaf spring 14.
After that, it is rotated by its own weight, its free end is brought into contact with the partition iron plate 17, and the bottom plate 10 is tilted below the covering part 2. Besides, the bottom plate lO and the slot 1
A closed space 23 is formed between the bottom surface of 6 (
(See Figure 5). Then, a supporting material such as gravel 24 is placed in the space on the side of the joint reinforcing bars 19.
There is no possibility of rotation (Fig. 40, Fig. 5).

Thereafter, concrete is placed in the space on the side of the reinforcing bar basket 18 in the slot 16 and hardened to form the unit wall 25. During concrete pouring, sheet 14 prevents its leakage (Fig. 4D) 6 After the concrete has hardened, slots 26 for adjacent unit walls are excavated. At this time, the excavator 2 is protected by the cover 2 of the protection device 1 for the 17 jointed reinforcing bars.
7, and the gravel 17 naturally collapses from the opening 5 during excavation and is removed together with the excavated soil in the trench hole 26 (FIGS. 4E and 7).

When the excavation of the trench hole 26 is almost completed, the bottom plate 10 is erected by pulling the wire 12, and the gravel 24 partially remaining on the bottom board 10 is dropped into the trench hole 26 side together with the excavated soil. Remove. Then, the protection device 1 is pulled up and removed with the bottom plate 10 erected as described above (FIG. 4F). Note that slime processing is performed using an air lift, etc., as in the past. Insert and install protective equipment N1 as described above, or pull up J! With fK, the bottom plate 10 is rotated within the slot 16, but since the bottom plate 10 is provided with a large number of through holes 15, the resistance due to muddy water etc. during rotation can be reduced.

Next, an assembly 28 similar to that described above is inserted into the slot 26 and the same process as described above is performed to overlap the reinforcing bar 11 of the assembly 28 and the joining reinforcing bar 19 protruding from the unit wall 25. After that, concrete is poured to form the adjacent unit walls 29, thereby integrating the adjacent unit walls 25 and 29 to construct a continuous wall with sufficient durability (4th G). figure).

The protective device 1 is not limited to the frame structure as described above, but can have various forms.For example, the protective device 1 may be constructed by joining steel plates so that the entire covering part is in the form of a gutter, An opening with a large diameter may be formed as appropriate.

According to this invention, when excavating a groove hole for an adjacent unit wall,
Since the joint reinforcing bars protruding from the concrete-cast unit wall can be covered and protected by the cover, the joint reinforcing bars will not be damaged by an excavator, and the bottom plate will close the joint reinforcing bars below. As a result, support materials such as gravel do not get trapped and remain in the space, and therefore, the joints are able to withstand earth pressure, water pressure, and horizontal forces at the same level as other parts of the continuous wall. You can expect sufficient durability. In addition, since a large number of openings are formed in the second cover, support materials such as gravel that have naturally collapsed from the openings can be removed when trenches for adjacent unit walls are excavated, making it easy to pull up and shorten the construction period. It is possible to reduce the

[Brief explanation of drawings]

FIG. 1 is a plan view showing an embodiment of the protection device according to the present invention, FIG. 2 is a side view of the same, FIG. 3 is a rear view of the same, and FIGS. 4A to 4G are the devices of the present invention. FIG. 5 is an enlarged vertical sectional view of FIG. 40, and FIG. 6 is an enlarged longitudinal sectional view of FIG. 4E. 1... Protective device 2... Cover 5... Opening
9... Leg part 10... IE board 11... Hinge 12... Wire 13... Pulley 15...
・Through holes 16, 26...Groove hole 17...Partition iron plate 18...Reinforcing bar basket 19...Joining reinforcing bar
2o... Assembly 23... Space 2
4...Gravel 25, 29...Unit wall s picture side part B...back part 4G flash 51 funeral 6 haze

Claims (1)

[Claims] 1. At the lower end of a vertical cover that is shaped like a gutter and has a pair of side surfaces spaced apart from each other and a back surface between the two side surfaces, and has a number of openings formed in both side surfaces and the back surface. , a leg part is vertically provided near the back part, and a base end of a bottom plate is provided on the leg part, the width is larger than the distance between the side parts, and the length is larger than the distance from the leg part to the front end of the side part. The bottom plate is pivotably pivoted in a vertical direction, and has one end fixed to the free end of the bottom plate with the other end of the cable body located above the cover, and the bottom plate is configured to adjust the length of the legs by tension and relaxation of the cable body, respectively. A protection device for joint reinforcing bars in an underground continuous wall, characterized in that the device is configured to rotate between a position standing up along the member and a position tilting toward the front end of the side surface.