JPS6136416A - Method of landslide-protecting joint for underground continuous wall - Google Patents

Abstract

PURPOSE:To perfect landslide protecting and cutting-off capability, by a method wherein an injection pipe is positioned within front and rear support pipes, and after a space between a pipe and a joint plate is closed by pouring mortar with a pressure, mortar is injected into the injection pipe to fill the pipe with the mortar. CONSTITUTION:A pretrench hole 14 is excavated in a ground E by an excavator, the excavation is conducted as the trench hole is full of water, a wall surface is prevented from collapse, and an assembly body 1 is inserted in the pretrench hole 14 for installation. Concrete is placed between partitions 2a and 2b, a post- trench hole 16 is excavated to insert an assembly body 17 thereinto for installation, and pipes 12a and 12b are positioned opposite to each other. A joint plate 19 is inserted between the pipes 12a and 12b for installation, mortar 23 is poured into a tube 22 with a pressure to close a space between each of the pipes 12a and 12b and the joint plate 19, and concrete is placed in a joint space S2. This causes a ground to be sufficiently durable to an earth pressure and an underground water pressure, and enables reliable prevention of collapse of a ground and leak of underground water.

Description

[Detailed Description of the Invention] This invention relates to an earth retaining method for joints in underground continuous walls.The length of underground continuous walls is limited depending on the gentle ground conditions, construction conditions, etc. It must be constructed from a plurality of unit walls, and joints occur between the unit walls that are in instant contact with each other.

Conventionally, various methods have been proposed for joining unit walls, one of which is to first construct a plurality of unit walls leaving a joint space, and after excavating the ground on one side of the unit walls, There is a construction method in which concrete is poured into the joint space and hardened to form the joint. This method has the advantage that the open cut space on one side of the unit wall communicates with the joint space, and muddy water in the joint space is removed, so slime remaining in the joint space can be reliably disposed of. However, measures against earth pressure and groundwater from the unexcavated ground in the joint space were not sufficient, and there was a risk of ground collapse and groundwater leakage.

In other words, in the past, the earth retaining plates provided on the front partition plate of the leading unit wall and the rear partition plate of the trailing unit wall were butted together in the joint space, and both earth retaining plates were used to counter earth pressure and groundwater pressure. However, it was impossible to avoid the formation of a gap between the two retaining plates, and it was difficult to adequately counter earth pressure and groundwater pressure. Therefore, the current situation is to use auxiliary construction methods such as chemical injection, or to apply reinforcing plates to the retaining plates when the ground is excavated.

This invention eliminates the drawbacks of the conventional method as described above,
A joint in a diaphragm wall that can completely prevent soil collapse and groundwater leakage by perfecting the earth retention and water-stopping properties of the uncut ground in the joint space without using auxiliary construction methods or pipes. The purpose is to provide the earth retaining method of the section.

That is, in this invention, after excavating a preceding trench, a wall reinforcing bar cage is fixed horizontally between a pair of front and rear partition plates having a width approximately equal to the width of the trench, and the front and rear partitions are The front and rear joint reinforcing bars are fixed horizontally to the plate on the opposite side of the reinforcing bar cage, and one side of the front and rear earth retaining plates is fixed to one end of the front and rear partition plate so as to protrude at right angles on the opposite side of the reinforcing bar cage. The end of the retaining plate is fixed, and a long groove along the axial direction is formed on the peripheral wall at the other end of the retaining plate.The front and rear supports have a pipe fixed on the opposite side of the long groove, and the assembly is inserted into the preceding groove hole. Then, concrete is poured between the front and rear partition plates and hardened to construct a leading unit wall, and then a trailing slot including the space between the end wall of the leading slot and the front partition plate is constructed. After excavation, an assembly similar to that described above is inserted into the trailing groove, and the rear support of the trailing assembly is installed.
The front supports of the eve and the leading unit wall face the pipe with a full distance between them, and the rear joint reinforcing bars of the trailing assembly and the front joint reinforcing bars of the leading unit wall are overlapped, and then the trailing assembly A trailing unit wall is constructed by pouring and hardening concrete between the front and rear partition plates, and then injection pipes are fixed to both ends in advance, and a pair of flexible tubes are attached to each side of the joint. The front and rear supports with opposite plates are inserted between the pipes through their long grooves, and the injection pipe is positioned in the front and rear supports, and then mortar is press-fitted into each tube to expand the tubes. Then, after closing the space between the front and rear receivers and the joint plate, inject mortar into the injection pipe and filling the inside of the injection pipe and the space between the front and rear receivers and the injection pipe. -The feature lies in the earth retaining method for joints in underground continuous walls.

An embodiment shown in the drawings will be described below.

As shown in Figure 1, the assembly l used in this invention construction method is
is equipped with a pair of front and rear partition plates 2m and 2bt'' having a width approximately equal to the width of the slot described later, and the partition plates 2m and 2b are, in this example, made by fixing channel steel 3' to both ends of the iron plate 3. A large number of longitudinal reinforcing bars 4 are installed between the partition plates 2 m long and 2 b.
A wall reinforcing bar @6, which is formed by fixing a horizontal reinforcing bar 5 to the wall, is fixed in a horizontal direction. In addition, the partition plate is 2m long, and the reinforcing bar cage 6 is installed on 2b.
At 0 opposite side pressure, a large number of front joint reinforcing bars 7IL and a rear joint reinforcing bar 7b formed by fixing horizontal reinforcing bars 9 to a large number of vertical reinforcing bars 8 are fixed, and further, at one side end of the partition plates 2a, 2b. One side end of the front and rear retaining plates 10a and 10b is fixed so as to protrude at right angles on the opposite side of the reinforcing bar gL6. The front and rear bearings have long grooves 11 along the axial direction in the peripheral wall at the other end of the retaining plates 10m and 10b.
2a and 12b are fixed on opposite sides of the long groove 11. 13 is a sheet for preventing concrete leakage.

Next, based on the construction method of constructing an underground continuous wall using the assembly 1 as described above, an earth retaining construction method for the joint portion will be explained.

As shown in Figure 2, a trench hole 14 is drilled into the ground E by an excavator.
During the excavation, the groove hole 14 is filled with muddy water in the same manner as before to prevent the wall from collapsing.

Next, the assembly l is inserted into the preceding groove 14, the front and rear partition plates 2a and 2b are supported by supporting materials (not shown), and concrete is poured between the partition plates 2m and Zb and hardened. Then, the preceding unit wall 15 is constructed. Next, as shown in FIG. 3, after excavating the trailing slot 16 including the space S between the front partition plate 2m and the end wall of the leading slot 14 (see FIG. 2), the trailing slot 16 is excavated. An assembly 17 similar to assembly 1 is inserted into the slot 16, and the rear receiver of this assembly 17 is connected to the pipe 1.
2b and the front support of the preceding unit wall 15 are opposed to the nosape 12m with an interval, and the rear joint reinforcing bar 7b of the assembly 17 and the front joint reinforcing bar 7& of the preceding unit wall 15 are overlapped.

Concrete is then poured between the front and rear partition plates 21 and 2b of the assembly 17 and hardened to construct the trailing unit wall 18.

Next, a joint plate 19 is inserted between the pipes 12m and 12b of the opposed front and rear supports. As shown in Figure 5, the joint plate 1
Injection pipes 20 are fixed to both ends of 9, a pair of receiving plates 21 are fixed to each side, and a flexible tube 22 is fixed to the injection pipe 20 side of each receiving plate 21. C,
The front and rear supports of the joint plate 19 are the long grooves 1 of the pipes 10a and 10b.
1 and then the inserted membrane n.

After installing the joint plate 19, apply mortar 23t to the tube 22.
It is press-fitted and expanded as shown by the chain line in FIG.

12b and the joint plate 19 are closed. Next, mortar 23 is press-fitted into the injection/eve 20, and the mortar is filled into the inside thereof and between the front and rear receiver pipes 10a, 10b and the injection pipe 20. In this way, the front and rear retaining plates 10
m, 10b are integrated through the joint plate 19 and mortar 23 to form an earth retaining wall 24 in the joint space S2 between the leading and trailing unit wall bodies 15 and 18. Thereafter, the unit walls and the earth retaining walls t--are sequentially formed in the same manner.

After constructing a predetermined number of unit wall tubes as described above, the WS
As shown in Figure 4, the ground on one side of the unit wall is excavated, and the excavated space S and the joint space S! km to remove the muddy water in the joint space S2. At this time, soil pressure and groundwater pressure act on the earth retaining wall 24 from the ground E on the other side of the unit walls 15 and 18, but since the earth retaining wall iJ1.24 is integrated as described above, it can sufficiently resist these pressures. This prevents ground collapse and groundwater leakage.

Next is the joint space S! After removing the slime adhering to the peripheral wall of , and cleaning it, concrete is poured into the joint space S and hardened, and in this way, the unit walls 15, 1B are
A diaphragm wall with an integrated underground wall will be constructed.

This invention is as described above, and after constructing the leading and trailing unit walls, in the joint space between the 100 unit walls,
The front earth retaining plate of the leading unit wall and the rear earth retaining plate of the trailing unit wall form an integrated earth retaining wall through joint plates and mortar, so that it can sufficiently resist earth pressure and groundwater pressure, and It is possible to reliably prevent the collapse of buildings and leakage of underground water. In addition, the above-mentioned earth retaining wall is constructed by installing receiving pipes on the front and rear earth retaining plates, and for both the retaining walls, a joint plate is inserted between the pipes, and then mortar is poured. It has the advantage that it can be formed with a lot of work and can be machined at low cost.

4, 121 plane (D lii 4'-Explanation gr 1) q, Figures 2 to 4 are planes showing planes 1 and 121 of the assembly used in this invention. FIG. 5 is a plan sectional view showing the construction procedure, and FIG. 5 is an enlarged plan sectional view showing a portion of the earth retaining wall.

1. 17...Assemblies 2a, 2b...Front and rear partition plates 6...Wall reinforcing bars 7A, 7b...
・Front and rear joint reinforcing bars foA, Job...Front extraction earth retaining board
11... Long grooves 12a, 12b... Front and rear receivers are pipes 14... Leading slot 15... Leading unit wall 16... Trailing slot 18... Trailing unit wall 19 ...Joint plate 20...Injection hole 22...Flexible tube 23...
・Mortar 24... Retaining wall C cover

Claims (1)

[Claims] 1. After excavating the preceding trench, a wall reinforcing bar cage is fixed horizontally between a pair of front and rear partition plates having a width approximately equal to the width of the trench, and the The front and rear joint reinforcing bars are fixed horizontally on the opposite side of the wall reinforcing bar cage, and the front and rear retaining plates are attached to one end of the front and rear partition plates so as to extend at right angles on the opposite side of the wall reinforcing bar cage. An assembly in which one end of the earth retaining plate is fixed, and a front and rear receiving pipe having a long groove formed in the peripheral wall along the axial direction on the other end of the retaining plate is fixed on the opposite side of the long groove is inserted into the preceding groove hole. Next, concrete is cast and hardened between the front and rear partition plates to construct a leading unit wall, and then a trailing groove including the space between the end wall of the leading slot and the front partition plate is constructed. After the hole is excavated, an assembly similar to the above is inserted and installed in the trailing groove, and the rear receiving pipe of the trailing assembly and the front receiving pipe of the leading unit wall are spaced apart from each other. At the same time, the rear joint reinforcing bars of the trailing assembly and the front joint reinforcing bars of the leading unit wall are overlapped, and then concrete is poured between the front and rear partition plates of the trailing assembly and hardened to form the wall of the trailing unit wall. After constructing the body, injection pipes are fixed in advance to both ends, and a joint plate with a pair of flexible tubes fixed to each side is inserted between the opposed front and rear receiving pipes through their long grooves. , the injection pipe is positioned in the front and rear receiving pipes, and then mortar is press-fitted into each of the tubes to expand the tubes, thereby closing the space between the front and rear receiving pipes and the joint plate; An earth retaining method for a joint in an underground continuous wall, characterized by injecting mortar into a pipe and filling the inside of the pipe, the front and rear receiving pipes, and between the injection pipes.