JPH1121877A - Groundwater vein restoration method using steel tube column retaining wall - Google Patents

Abstract

(57) [Abstract] [Problem] To construct a structure capable of restoring a groundwater vein using a steel tube column retaining wall. SOLUTION: Pillar soil retaining walls A, A are formed with a construction ground C interposed therebetween. At this time, the number of the steel pipes serving as the retaining members is limited at the upper end of the steel pipe as far as the water flow target range is concerned, and the other steel pipes 1 are installed to a required depth, and the lower part of the fixed steel pipe 1a is provided. The soil retaining wall is formed only by the soil cement wall 3a. After the construction is completed, a water hole 5 is opened in the soil cement wall 3a using an auger screw or the like, and the flow of the groundwater vein D is restored.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to an earth retaining wall using a steel pipe used as a water stop wall in the construction of an underground structure or the like. The present invention relates to a method of restoring a groundwater vein using a steel pipe column retaining wall.

[0002]

2. Description of the Related Art In the construction of underground structures, etc., earth retaining walls are formed around the construction area, and ground excavation of underground portions and construction of buildings are performed. It is buried after the end. Since the embankment walls are important for water-shielding, continuous underground walls made of reinforced concrete and steel-tube column-arboring walls are used.However, the formation of these walls will block groundwater veins and increase groundwater levels. They often cause fluctuations and adversely affect the surrounding environment. In particular, in recent years, as construction has become larger, this has become a social problem.

[0003] In order to solve this problem, in the underground continuous retaining wall using reinforced concrete, as a countermeasure for permeating groundwater, the shape of the inserted reinforcing bar or the property of cast-in-place concrete is taken as a measure. And the like have been proposed. In addition, there is an actual example in which water holes are formed in the retaining wall using a propulsion method to restore the groundwater flow.

[0004]

However, in the above-mentioned various methods of making the retaining wall made of reinforced concrete impervious, the construction is troublesome and requires a large amount of cost. There is a problem that a construction site (a shaft) for installing equipment for the construction method is required, so that the construction range is widened, and the construction period and construction cost are increased. In addition, in the case of the steel pipe column retaining wall, it is difficult to change the structure of the prefabricated steel pipe because it is made of a pre-made steel pipe, so that it is not suitable as a structure for restoring the groundwater flow.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and uses a steel tube column row retaining wall which has many advantages, such as good workability and excellent strength and water shielding, and is used as the retaining wall. After that, through the work of the minimum necessary area on the ground, water holes were formed in the soil wall part only with soil cement formed at the time of construction of the earth retaining wall, so that the flow of the groundwater vein could be restored. It is an object of the present invention to provide a groundwater vein restoration structure and its construction method, which are excellent in workability and workability.

[0006]

The construction of the present invention for achieving the above object will be described with reference to the drawings corresponding to the embodiments. In the construction of the steel pipe column retaining wall A to be constructed, some of the steel pipes serving as the retaining members were laid down close to the groundwater vein D, and the other steel pipes 1 were laid down to the required depth and retained. The lower part of the steel pipe 1a is formed on a retaining wall 3a made of only soil cement having no steel pipe, and a water hole 5 communicating with the groundwater vein D is provided on the retaining wall 3a.

According to the construction method of claim 2, in the construction method of claim 1, the water passage holes 5, 5 of the steel pipe column row soil retaining walls A, A formed across the construction ground C are laid with crushed stone or the like. It is characterized by being connected by a water passage layer 13 or a communication pipe 14.

According to a third aspect of the present invention, in the method of the second aspect, the lower portion is connected to the water hole 5 on the back ground E side of the steel pipe column retaining wall A in contact with the retaining wall A. A permeable layer F filled with crushed stone or the like is created.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 4 show an embodiment of a first method of the present invention, and FIGS. 5 to 8 show second and third embodiments.
FIG. 9 shows an embodiment of the method of the present invention, and FIGS.
13 shows an example of means for opening a water hole.

First, an embodiment of the first method according to the present invention will be described with reference to FIGS. In the present invention, a steel pipe column retaining wall (hereinafter referred to as retaining wall) A is used. This retaining wall A is used for the construction ground C of the underground structure B.
It is built facing the ground on both sides across the.

As is well known in the art, the retaining wall A connects the steel pipes 1, 1 provided with the joint members 2 on the opposing outer surfaces thereof by fitting the joint members 2, 2 to each other while connecting the soil cement 3 to the steel pipes. It is carried out by sinking into the filled excavation hole 4. This method is called a so-called ONS method.

The earth retaining wall A is usually formed by being embedded in the ground deeper than the groundwater vein D. At this time, in this first construction method, as shown in FIGS. In the direction
A range (a range to be passed) a through which water is passed is set, and the steel pipe 1a corresponding to the range a is kept settled in the soil cement 3 to a depth near the upper end of the underground water vein D. Therefore, in the water flow symmetry range a, the steel pipe 1a
The portion below is only the retaining wall 3a made of only soil cement without a steel pipe as a core material. A water hole 5 communicating with the groundwater vein D is formed in the soil cement wall 3a.
(See FIGS. 3 and 4). The work of opening the water hole 5 may be performed after excavating the construction ground C between the soil retaining walls A, A, or after constructing the underground structure B there.

Various methods are conceivable as a method for opening the water hole 5. 9 to 13 illustrate the method. The example shown in FIG. 9 is a steel pipe 1a in the water flow symmetry range a.
Inside, a conventionally known auger screw 6 for digging is inserted to excavate the soil cement 3 in the steel pipe 1a.
At the same time, the soil cement wall 3a below the lower end of the steel pipe 1a is excavated and removed to almost the lower end of the groundwater vein D by expanding the excavating blade 7 at the tip. As a result, the water hole 5 is opened, and the groundwater vein D blocked by the retaining walls A, A is communicated through the water holes 5, 5 to restore the water flow.

FIGS. 10 and 11 show an example of a packer 10 which expands and contracts by injecting and discharging a fluid such as air or water at the tip of a pipe 9.
The opening device 8 provided with the steel pipe 1a is inserted in advance so that the packer 10 is positioned at the lower end of the steel pipe 1a.
Is immersed in the soil cement 3 (FIG. 10), and while the soil cement 3 is not hardened, as shown in FIG. 11, a fluid is injected from the ground to expand the packer 8 to remove the soil cement and stop. Water is supplied, and after completion of use as a temporary retaining wall, the packer is contracted to open the water passage 5.

FIG. 12 shows an example in which the explosive 11 such as dynamite is loaded at the tip of the hole 9 provided in the soil cement 3 after the earth retaining wall is constructed, and the explosion is exploded by the operation from the ground to open the water hole 5. . Further, FIG. 13 shows that the static crushing agent 12 is loaded on the tip of the hole 9 provided in the soil cement 3 after the construction of the retaining wall, and the static crushing agent 12 is expanded by an operation from the ground so that the water hole 5 is formed. Is to open.

In the above embodiment, the number of the steel pipes 1a in the water symmetry range a is one. However, as shown in FIG. ,
The water inlet 5 can be made large.

The first construction method is applied when the groundwater vein D is at a position deeper than the lower end level of the underground structure B to be constructed and is deeper than the excavation root cutting level b (see FIG. 3). You. The groundwater vein D is temporarily cut off by the formation of the retaining walls A, A. However, by opening the water holes 5, 5 to the retaining walls A, A, the ground E on one side and the ground E on the other side are opened. Then, the groundwater vein D is communicated through the water holes 5, 5, and is restored.

Next, an embodiment of the second method according to claim 2 will be described. This construction method is applied when the groundwater vein D is at a position deeper than the lower end level of the underground structure B to be constructed, as shown in FIG. In this case, as shown in the figure, the excavation between the soil retaining walls A, A is performed to the lower end level of the underground water vein D, and the excavation is performed at a position corresponding to the underground water vein D between it and the lower end of the underground structure B. A water layer 13 laid with crushed stones or the like is provided over the water holes 5 and 5 of the retaining walls A and A. Further, as shown in FIG.
Alternatively, the two water holes 5, 5 can be connected to each other by the communication pipe 14 so as to allow water to flow. Since the means for opening the water hole 5 in the retaining wall A is as described above,
Description is omitted. In the case of this construction method, the water that has entered the water hole 5 of one retaining wall A flows through the water layer 13 or the communication pipe 14 to the water hole 5 of the other retaining wall A, and the groundwater vein D Is restored.

Next, an embodiment of a third method according to claim 3 will be described. This construction method is applied when the groundwater vein D is at a position shallower than the lower end level of the underground structure B to be constructed, as shown in FIG. In this method, the water hole 5 of the retaining wall A is laid so that the lower end of the steel pipe 1a is located near the lower end of the underground structure B so as to be deeper than the lower end of the underground structure B.

Then, on the back ground E side of the retaining wall A, a permeable layer F filled with crushed stone or the like is formed in contact with the retaining wall A and has a depth up to the opening position of the water hole 5. Further, a water-permeable layer 13 laid with crushed stones or the like is provided and connected between the open positions of the water-permeable holes 5, 5 of the soil retaining walls A, A, as in the embodiment of FIG. Underground structures will be constructed on top of it. In addition,
Instead of the water-permeable layer 13, a communication pipe 14 can be provided as in the embodiment of FIG. The opening of the water hole 5 in the retaining wall A is the same as described above.

In this case, the water flow of the groundwater vein D flows into one permeable layer F and descends, passes through the water hole 5 of one retaining wall A, passes through the water layer 13 (or the communication pipe 14), and the other. The water enters the other permeable layer F from the water hole 5 of the retaining wall A and flows out to the groundwater vein D, so that the water flow is restored. The permeable layer F is not limited to being provided on the entire surface in the length direction of the retaining wall A, but may be provided at intervals in the longitudinal direction of the retaining wall A, for example, for each area surrounding the location where the water hole 5 is opened. It can also be provided in pieces.

[0022]

As described above, according to the present invention,
Conventionally, in the construction of underground structures, etc., using steel pipe column soil retaining walls that are buried as high water-impervious retaining walls, underneath, forming soil retaining walls only of soil cement without steel pipes, In addition, since a water hole has been opened, the steel pipe column retaining wall functioning as a water impervious wall at the time of construction can function as a water penetrating wall to restore the groundwater vein after construction. .

Further, since the steel pipe column-retained retaining wall having good water-shielding properties and excellent proof strength and workability can be provided with a water-passing function by simple work from the ground, the structure for restoring the groundwater vein is economical. The groundwater flow can be restored and maintained smoothly without any power, and the surrounding environment can be maintained well.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing a state in which a retaining wall is formed in an embodiment of a first construction method of the present invention.

FIG. 2 is a front view showing the earth retaining wall.

FIG. 3 is a side sectional view showing a state in which the water hole is opened.

FIG. 4 is a front view showing the earth retaining wall.

FIG. 5 is a front view of a main part of a retaining wall showing another embodiment.

FIG. 6 is a side sectional view showing an embodiment of a second method of the present invention.

FIG. 7 is a sectional side view of a main part showing another embodiment.

FIG. 8 is a side sectional view showing an embodiment of a third method of the present invention.

FIG. 9 is a side sectional view showing one embodiment of opening a water hole;

FIG. 10 is a side sectional view showing another embodiment.

FIG. 11 is a side sectional view showing a state when the packer is expanded in the embodiment.

FIG. 12 is a side sectional view showing still another embodiment of opening a water hole.

FIG. 13 is a side sectional view showing still another embodiment.

[Explanation of symbols]

 Reference Signs List A A retaining wall B Underground structure C Construction ground D Groundwater vein E Back ground F Permeable layer 1, 1a Steel pipe 2 Joint material 3 Soil cement 3a Soil cement retaining wall 5 Water hole 6 Auger screw 7 Drilling blade 8 Opening device 9 Hole 10 Packer 11 Explosive 12 Static crushing agent 13 Aquifer 14 Connecting pipe

Claims (3)

[Claims] 1. In the construction of a steel pipe column retaining wall formed across a construction ground, a part of a steel pipe serving as a retaining member is kept close to a groundwater vein, and other steel pipes are required. A steel pipe column characterized by forming a lower part of a steel pipe sunk to the depth and retained, on a retaining wall made of only soil cement having no steel pipe, and having a water hole communicating with a groundwater vein on the retaining wall. Groundwater vein restoration method using row retaining walls. 2. The method according to claim 1, wherein the water holes of the two steel pipe column soil retaining walls formed across the construction ground are connected by a water layer or a communication pipe laid with crushed stones or the like. Groundwater vein restoration method using steel column pillar retaining wall. 3. A permeable layer filled with crushed stone or the like, which is partially in contact with the retaining wall and is connected to the water passage hole, is formed on the back ground side of the steel pipe column retaining wall. Item 4. A method for restoring groundwater veins using the steel pipe column soil retaining wall according to item 2.