JPS6098010A - Execution of underground continuous wall - Google Patents

Abstract

PURPOSE:To efficiently erect underground continuous wall by a method that, after preventing adherence of slime by covering horizontal reinforcements of reinforced cages for a preceding panel with protective plates, the reinforcements are set so as to lap with horizontal reinforcements of reinforced cages for a succeeding panel, and concrete is placed. CONSTITUTION:After reinforced cages 10A for the preceding panel 10 are set in a preceding excavated ditch 35, the preceding panel 10 is made by placing concrete. Then, projected horizontal reinforcements 13A of the cages 10A are covered by setting the protective plates 22 to the end of the panel 10. After a succeeding ditch 40 is excavated, the end of the panel 10 is cleaned in pulling up the protective plates 22. The reinforced cages 11A for the succeeding panel are set in the succeeding excavated ditches 40 so that the horizontal reinforcements 13B lap with the reinforcements 13A of the cages 10A of the panel 10. Then, the succeeding panel 11 is built by placing concrete.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention provides construction methods that are effective for constructing underground continuous walls, particularly cylindrical continuous walls used as earth retaining and water-stop walls for cylindrical underground tanks. It is about the method.

<Problems to be solved by this invention> Figures 1 and 2 show an outline of the construction of an underground tank. They must be joined together to form a single cylindrical shell structure, and for this reason the joint must have bending rigidity.

Therefore, as shown in Figure 3, the weight of the preceding panel reinforcing bar is 5A.
A reinforcing bar overlap joint method is adopted in which the end transverse bars of the trailing panel reinforcing bars 1i4A are lapped together.

In the case of such a method, as shown in Figures 4 and 5, 1
After building the preceding panels 5 on both sides.

Excavating a trailing excavation trench 5 in the center and constructing a trailing panel 4 - However, after excavating the trench 5, there is a problem that debris accumulates in a place P that cannot be excavated, making it impossible to replace it with concrete. .

<Seventh Object of the Invention> This invention was proposed in view of the above circumstances, and its purpose is to provide a construction method that can efficiently and economically construct an underground continuous wall using reinforcing bar lap joints. It is in.

<Structure of the Invention> The method for constructing an underground continuous wall according to the present invention is to provide a previously excavated trench with a partition plate at the longitudinal end of the trench, and to extend a transverse strip from the partition plate with a predetermined length. erecting a preceding panel reinforcing bar box configured to protrude and pouring concrete; erecting a protection plate having a substantially U-shaped cross section capable of covering the protruding horizontal reinforcement of the preceding panel reinforcing bar box along the partition plate; Next, after excavating a coexisting trailing excavation groove, the retaining plate is pulled out, and the weight of the trailing panel reinforcing bar is placed in the trailing excavation groove so that the horizontal reinforcement at the longitudinal end of the groove is aligned with the edge of the leading panel reinforcing bar. The structure was constructed so that it overlapped with the protruding horizontal reinforcement, and concrete was poured.

<Example> The present invention will be described below based on an illustrative example. This embodiment is a case of a cylindrical underground continuous wall of an underground tank, and leading panels 10 and trailing panels 11 curved at a predetermined curvature are alternately arranged as shown in FIGS. 6 and 7. established and configured.

Reinforcement cage 10A on the leading panel, reinforcing bar cage 11A on the trailing panel
have longitudinal reinforcements 12 and horizontal reinforcements 15, respectively, and are configured to resist with lattice reinforcements 14 and the like to maintain a predetermined curvature.Furthermore, the leading panel reinforcing bar weight 10A has A partition steel plate 15 is provided, and a transverse reinforcement 15A is configured to protrude from the partition steel plate 15 by a predetermined length. The horizontal reinforcement 15 and the vertical reinforcement 12 are screw bars, and the horizontal reinforcement 15 is fixed to the partition steel plate 15 with nuts 16.

The partition steel plate 15 has water-stop steel plates 1.17' on both sides, a concrete wrap prevention sheet 1B and concrete outflow prevention rubber plates 19 on both ends, and semicircular trailing panels on both ends. Guide part 20 that curves to the side
is formed and is used as a guide when installing the protection board, which will be described later.

The horizontal reinforcement 15B at the end of the trailing panel reinforcing bar weight 11A is bent inward to overlap the horizontal reinforcement 15A of the preceding panel reinforcing bar basket 10A at a predetermined distance. moreover,
The vertical bars 12 of the horizontal bars 15B are arranged on the inside, and a flat par 21 is arranged on the inside of the horizontal bars 15A, and this flat par 21 serves as a guide when inserting the trailing panel reinforcing bar 1tA.

Next, as shown in FIG. 9, the protection plate 22 is attached to the end of the leading panel 10 to protect this end during excavation of the trailing excavation trench, and has a cross-sectional shape. This protection plate 22 consists of a base plate 22A having a recessed portion in the center, and an extension plate 22B that extends from the base plate 22A toward the partition steel plate 151 without contacting the side wall of the preceding excavation groove.
A locking tube 23 is attached to the outer surface of 2B. After the construction of the partition steel plate 15 is completed, if muddy water is injected into the locking tube 25 and it swells, the gap between the protection plate 22 and the side wall of the preceding excavation trench is closed, thereby preventing the intrusion of excavated debris. become.

Furthermore, the protection plate 22 is divided into a plurality of lofts and added to them one after another, similar to the reinforcing bar cages 10A and 11A.
As shown in the tPJ10 diagram, only the bottom protection plate 22 is
A locking protrusion 24 that engages with the guide portion 20 is provided protruding from the tip of the extension plate 22B. This is to make it possible to easily follow the vertical deflection of the preceding panel end, that is, the partition steel plate 15, during erection. Furthermore, on such a lowermost protection plate 22, a partition steel plate cleaning brush 2 is provided.
5. Protruding horizontal stripe 15A cleaning brush 26. Water stop steel plate 16?
i# sweeping brush 27 is connected to each member 15, 15A, 1
6 in a pressed state. The ends of the leading panels are left in muddy water for a long period of time, so slime is attached to them.
Although it is necessary to remove excavated debris, with this configuration, cleaning can be performed at the same time as the protection plate 22 is pulled out.

Next, an example of the bonding between the protection plates 22 and the protection plates 22 will be described in the 11th
Figure 12 shows that. This allows a connecting plate 29 having bolt holes 28 to protrude from the upper end of the protective plate 22 and attaching it to the protective plate 22I via the reinforcing plate 3o.
Attach a reinforcing plate S2 having bolt holes 51 to the lower end of 2,
It is connected with bolts and nuts. Note that the locking tube 23 is connected to the lower end with a thin rubber plate 55.

Next, FIG. 15 and FIG. 14 show the preceding panel guide 34, which includes a pipe 56 inserted into the end of the preceding excavation groove 55, and a pipe 56 arranged at intervals in the vertical direction. It consists of a positioning member 57. This positioning member 57 includes a semicircular cylindrical portion 6B located in a semicircular groove at the end of the preceding excavation groove 55, and a pair of protruding portions 39 that protrude toward the partition steel plate 15 and sandwich the water stop steel plate 17. We are prepared.

In the above configuration, construction is performed in the following process order.

■ As shown in FIG. 15, five leading grooves 55 are excavated.

(2) As shown in FIG. 16, the leading panel guides 54 are installed at both ends of the leading groove 35.

■ As shown in Figure 17, erect the preceding panel reinforcing bars with a weight of 10A.

(2) When concrete is poured as shown in FIG. 18, the preceding panel 10 is obtained as shown in FIG. 19.

■ As shown in Figure 20, attach the protective plate 22 to the preceding panel 1.
Built in at the end of 0.

■ As shown in FIG. 21, a trailing groove 40 is excavated.

Perform slime processing as shown in rPJ22 diagram.

■ As shown in FIG. 23, the end portion of the leading panel 10 is cleaned while pulling out the protection plate 22. ■ As shown in FIG. 24, the trailing panel reinforcing bar cage iIA is erected.

■ As shown in Figure 25, concrete is poured to obtain trailing panels.

By sequentially repeating these steps in the circumferential direction, a cylindrical underground continuous wall is constructed.

Note that 1 and above are shown for cylindrical underground walls, but
The construction method of the present invention can also be effectively applied to linear continuous walls.

<Effects of the Invention> As mentioned above, according to the present invention, since a protective plate with a relatively simple structure is used, underground continuous walls using reinforcing bar lap joints can be constructed efficiently and economically.

[Brief explanation of the drawing]

Figures 1 and 2 are cross-sectional views showing the outline of underground tank construction, Figure 3 is a schematic plan view showing reinforcing bar lap joints for underground walls, and Figures 4 and 5 are underground tank construction diagrams. FIG. 3 is a plan view showing a method for excavating an excavation groove in a medium continuous wall. FIG. 6 is a longitudinal sectional view, and FIG. 6 is a plan view showing the preceding panel. FIG. 7 is a plan view showing the trailing panel, and FIG. 8 is a plan view showing the trailing panel. FIG. 9 is a plan view showing the protection plate of the preceding panel, FIG. 10 is a perspective view showing the lower end thereof, and FIG. 11 is the joint portion of the bending plate. Figure @12 is a perspective view showing the connection status of the protection plate,
Figures 15 and 14 are a plan view and a front view showing the preceding panel guide, and Figures #B15 to 25 are vertical sectional views showing the construction method according to the present invention in the order of steps. Tank, 2... Underground continuous wall, S... Leading panel, 4... Trailing panel, 5... Trailing excavation trench% 10...
Leading panel, 11... Trailing panel, IOA, 11A...
Reinforcing bar weight, 12... Vertical bar, 15.15"A, 15B...
Transverse bar, 14... Lattice bar, 15... Partition steel plate, 16...
Nut, 17.17'...Waterstop steel plate, 1B...Sheet for preventing concrete from going around, 19...Rubber plate for preventing concrete from flowing out, 20...Guide part, 21...Flat bar, 22...Protection plate, 22A ··substrate. 22B: Extension plate, 2S: Locking tube. 24... Retaining protrusion, 25, 26. 27... Cleaning brush, 28... Bolt hole, 29 - Joint plate, 500 @ Reinforcement plate, 51-I Bolt hole, 52-11 Reinforcement plate, 55. - Rubber plate, 54... Leading panel guide, 55... Leading excavation groove, 56... Pipe, 57... Positioning member, 58... Cylindrical part, 59... Projecting part, 40... Trailing excavated groove.・;-9: ! 4)10 Figure! 2 jil I14 '10 Figure 12',! S 1Gl,, 1 ;'i 17 1>:1 :t'19 11 ・:See 22111 2nd]l; ;+4j 24 1' 1 21 25 1 Go J

Claims (1)

[Claims] (1) In the previously excavated trench, a preceding panel reinforcing cage is erected, which has a partition plate at the longitudinal end of the groove and is configured such that the transverse reinforcement protrudes by a predetermined length from the partition plate. After pouring concrete and erecting a membrane retaining plate with a substantially U-shaped cross section that can crush the protruding horizontal bars of the preceding panel reinforcing bar cage along the partition plate, and then excavating an adjacent trailing excavation groove, Pull out the retaining plate, move it, and place the trailing panel reinforcing bars in the trailing excavation groove so that the horizontal reinforcement at the longitudinal end of the groove overlaps with the protruding horizontal reinforcement of the preceding panel reinforcing bar basket. A construction method for an underground continuous wall characterized by pouring concrete.