JPH083982A - Water-permeable underground continuous structure and manufacture thereof - Google Patents

Abstract

PURPOSE:To enable uuderground water to pass through underground walls and an underground continuous structure built between the walls. CONSTITUTION:An underground wall 2 is constructed according to the width dimensions of an underground continuous structure to be constructed. A water- permeable box 3 is integral with a cage to be set in the wall 1. An outer side wall of the box 3 is constitutied of waterproof double doors 3a that open on hinges and an inner side wall is constituted of a thin steel plate which can be easily cut off by melting it, and a lattice-like fence 3d is disposed inside the inner side wall. And the ground is excavated as far as a bottom surface of a structure which is to be built in the inner side area partitioned by the wall 11. Next, a trench 6a is excavated across the structure and an inside wall is cut off and thereafter crushed stones 6b are put into the trench 6a to complete a water-permeable channel 6. Further an underground continuous structure 8 is constructed in an inner area located between the walls 1 and thereafter soil is filled into a space above the structure 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an underground continuous structure which enables the passage of groundwater and a construction method thereof.

[0002]

2. Description of the Related Art Conventionally, an underground continuous wall method has been used to construct an underground continuous structure having a long extension such as a road, a subway, and a common ditch. This method is
A pair of underground continuous walls that reach the impermeable layer along both sides of the underground continuous structure to be constructed is constructed, and then the underground continuous wall is used as a retaining wall to excavate the interior to a predetermined depth. After constructing an underground continuous structure inside this, the upper part of the structure is backfilled.

[0003]

However, in such a construction method, since the underground continuous wall is constructed up to the depth reaching the impermeable layer, when the groundwater flow is blocked by these continuous walls. There are various problems due to the stagnation of groundwater flow. For example, on the upstream side, the groundwater level rises, which causes problems such as water leakage to the basement of the structure. On the other hand, on the downstream side, the groundwater level drops, which causes problems such as well death, dry ground, and subsidence.

The present invention solves the above problems, and an object of the present invention is to provide groundwater which allows underground water to pass through the underground wall and the underground structure constructed between them. A medium continuous structure and a method for constructing the same are provided.

[0005]

Means for Solving the Problems In order to achieve the above object, a water-permeable underground continuous structure according to the present invention is an underground continuous structure constructed between a pair of underground continuous walls. ,
A water passage that is located above and below or below the underground continuous structure and that crosses the underground continuous structure, and communicates with this water passage, and penetrates the pair of underground continuous walls in the wall thickness direction. And a water passage hole formed as an opening (claim 1).

In this case, the water passage may be formed by disposing crushed stones in a groove formed above and below or only below the underground continuous structure (claim 2), or the water passage hole may be formed. A hollow box type water-passing box which is integrated with a reinforcing bar cage built in the underground continuous wall and has a thickness substantially equal to the wall thickness of the underground continuous wall It is possible (Claim 3).

Further, the method for constructing a continuous underground structure according to the present invention is a pair of continuous underground structures in which a hollow box type water passage box capable of opening inner and outer walls is integrated with a rebar cage. The step of constructing a wall, the step of excavating the ground sandwiched by the underground continuous wall to the bottom position of the underground continuous structure to be constructed, and the step of traversing the underground continuous structure on the ground surface exposed by the excavation Direction excavating a groove in the direction, a step of opening an inner wall body of the water passage box and arranging crushed stones in the groove to form a water passage, and an underground continuous structure between the underground continuous walls And a step of opening the outer wall of the water passage box are performed in order (claim 4).

[0008]

[Advantage] According to the underground continuous structure capable of passing water through the above structure, the underground water is formed through the water passage formed under the bottom surface of the underground continuous structure and the water passage hole formed in the underground wall. Since it circulates, the underground water flow is not blocked by the underground structure.

When crushed stones are arranged in the groove engraved below the continuous underground wall to form a water passage, a water passage having a simple structure but high water permeability can be obtained. Opening the inner and outer wall bodies of the hollow box type water passage box, which has the water passage hole integrated with the rebar cage built in the underground wall and has a thickness dimension almost equal to the wall thickness of the underground wall. With this configuration, the water passage hole can be easily formed.

When the construction method of the present invention is adopted, water can be passed through the ordinary underground wall construction method only by adding the step of opening the wall body of the water box and the step of constructing the water passage. A medium continuous structure can be constructed.

[0011]

EXAMPLE An example of the present invention will be described in detail below in accordance with a construction procedure. 1 (a) to 1 (c) show the procedure for constructing an underground continuous wall, and the impermeable layer E1 from the ground surface at the construction position.
A pair of underground continuous walls 1 leading to is built in the underground E. This underground continuous wall 1 is constructed by a normal underground continuous wall construction method according to the width dimension of the underground continuous structure constructed as shown in (a). That is, each underground continuous wall 1
The preceding excavation groove 1a is excavated at a predetermined interval, the rebar cage 2 is built in the excavation groove 1a as shown in (b), and then concrete is placed using a tremie pipe or the like. As shown in (c), after the leading panel is formed, the trailing panel is spliced between the leading panels in the direction orthogonal to the paper surface.

A plurality of water flow boxes 3 are integrated in the reinforcing bar cage 2 at two positions in the height direction thereof and at predetermined intervals in a direction orthogonal to the plane of the drawing. The water passage boxes 3 are provided facing each other with the continuous walls 1 on both sides, the lower water passage box 3B is located below the bottom surface of the underground continuous structure to be constructed, and the upper water passage box 3A is in the same ground. The mounting position for the rebar cage 2 is set so as to be located above the top surface of the structure. Each water flow box 3 is a hollow steel plate,
The width dimension thereof is substantially equal to the thickness dimension of the continuous wall 1. The water passage box 3 (3A, 3B) has an outer wall body as shown in FIG.
The watertight door 3a that can be opened to the inside as shown in Fig. 3 is provided. The door 3a is always locked in the closing direction by the jack 3b against the groundwater pressure, and the jack 3b is operated by remote control. It is opened by doing. The inner wall 3c is made of a thin steel plate or the like that can be easily cut off by fusing, and
A grid-like fence 3d is arranged inside thereof.

After the continuous wall 1 is completed, the watertightly partitioned inner side of the continuous wall 1 is raised 4, as shown in FIG.
The supporting structure such as the cross beam 5 is used to support and cut the bottom of the structure to be constructed. The bottom of the ground exposed by this excavation coincides with the upper edge of the inner wall 3c of the lower water passage box 3.

Next, as shown in FIG. 4, each inner wall body 3c
A trench 6Ba is cut in a direction that crosses the underground continuous structure in a cross-sectional direction so as to connect between the inner wall bodies 3 exposed thereby.
The inside of each water passage box 3 is opened by cutting out c by fusing or the like. After that, crushed stone 6B in the groove 6Ba
If b is input, the water passage 6B is completed. At this time, since the water passage box 3 and the groove 6Ba are separated by the fence 3d, water can be passed between the both and the crushed stone 6Bb does not enter the water passage box 3. Absent. Note that the fence 3d may not be provided in the water passage box 3 from the beginning, but may be provided when the inner wall body 3c is cut off.

After completion of the water passage 6B, as shown in FIG.
The underground continuous structure 8 is built inside the continuous wall 1. This structure 8 is a watertight structure such as a subway, an underground road, an underground joint ditch, etc., and a normal construction method can be adopted.

After the continuous underground structure 8 is constructed, the groove 6Aa is formed and the upper side thereof is backfilled, and the water passage box 3A whose lower edge coincides with the top end portion thereof is opened in the same manner as described above to form the groove. By filling 6Aa with crushed stone 6Ab, a water passage 6A is also formed on the upper side.

Thereafter, the water flow box 3 is operated by remote control.
When the door 3a of (3A, 3B) is opened, water passage holes that penetrate the cross section of the continuous wall 1 are opened, and groundwater passes through these water passage holes and water passages 6 (6A, 6B) upstream as shown by arrows. Side to the downstream side. When the door 3a opens
On the lower side, it is performed at the time when the underground structure 8 does not rise due to water pressure, and on the upper side, the time when the circulation of groundwater does not hinder the construction.

Further, the cross-sectional dimensions of the water passage 6, the construction interval, and the opening cross-section of the water passage box 3 are designed in accordance with the required amount of groundwater flow obtained through preliminary surveys, and the door 3a of the water passage box 3 and the like. The withstand pressure strength of is also set according to the groundwater pressure.

In the above embodiment, the underground continuous structure 8
However, the present invention can be applied to the case where the structure 8 is constructed with the underground continuous wall 1 at a predetermined distance. In this case, Not only above the underground continuous wall 1, but also on the side of the underground continuous wall 1 will be backfilled.

Further, in the above embodiment, the underground continuous structure 8
The water passage 6 was formed above and below. In this case, as shown in FIG. 5, when the groundwater level WL is high or it is suitable for draining water that has penetrated into the ground, it is possible to communicate even if only below the groundwater level WL regardless of fluctuations in the groundwater level WL. Since the groundwater is passed through the pipe system, the upper waterway is not always required.

[0021]

As described above in detail with reference to the embodiments, the water-permeable underground continuous structure according to the present invention is formed only above and below or below the underground continuous structure. Since groundwater flows through the water passage and the water holes formed in the underground wall, the underground water flow is not blocked by the underground structure, and various groundwater flows such as ground subsidence are blocked. It can prevent harmful effects.

Further, according to the method of constructing an underground continuous structure capable of passing water according to the present invention, the step of opening the wall of the water box and the step of forming the water passage are added to the ordinary underground continuous wall construction method. Only by doing so, it is possible to easily construct a continuous underground structure capable of passing water.

[Brief description of drawings]

1A to 1C are cross-sectional explanatory views showing a procedure for constructing an underground continuous wall.

FIG. 2 is a cross-sectional view showing the structure of a water passage box.

FIG. 3 is a cross-sectional view showing a state in which the inside sandwiched between underground continuous walls is cut open.

FIG. 4 is a perspective view showing a state of opening an inner exposed surface of a water passage box and forming a water passage.

FIG. 5 is a cross-sectional view showing a completed state of a continuous underground structure capable of passing water.

[Explanation of symbols] 1 underground continuous wall 2 rebar cage 3 (3A, 3B) water passage box 3a watertight door (outer wall body) 3c inner side wall body 3d fence 6 (6A, 6B) water passage 6a groove 6b crushed stone 8 ground Medium continuous structure

Claims (4)

[Claims] 1. An underground continuous structure constructed between a pair of underground continuous walls, which is located only above, below, or below the underground continuous structure and which passes through the underground continuous structure. An underground continuous structure capable of passing water, comprising: a water channel; and a water hole communicating with the water channel and having a water hole formed by penetrating the pair of underground walls in the wall thickness direction. . 2. The water passage according to claim 1, wherein the water passage has crushed stones arranged in grooves formed above and below or only below the underground continuous structure. Continuous underground structure. 3. A hollow box type water passage, wherein the water passage hole is integrated with a reinforcing bar cage built in the underground continuous wall and has a thickness dimension substantially equal to the wall thickness of the underground continuous wall. The underground continuous structure capable of passing water according to claim 1 or 2, wherein the inner and outer walls of the box are opened. 4. A step of constructing a pair of underground continuous walls in which a hollow box-type water passage box capable of opening the inner and outer wall bodies is built, and a pair of underground continuous walls are built in, and sandwiched between the underground continuous walls. A step of excavating the ground to the bottom surface position of the underground continuous structure to be constructed, a step of excavating a groove in the direction traversing the underground continuous structure on the ground surface exposed by the excavation, and the water passage box A step of opening an inner wall body and arranging crushed stones in the groove to form a water passage; a step of constructing an underground continuous structure between the underground continuous walls; and an outer wall body of the water passage box A method for constructing a continuous underground structure capable of passing water, characterized by sequentially performing the step of opening the water.