JP3314697B2 - Segment for intake tunnel - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a segment for an intake tunnel, and more particularly to a segment suitable for intake used to introduce seawater into a seawater treatment facility such as a seawater desalination plant.

[0002]

2. Description of the Related Art In an island or a desert area with little rainfall, a seawater desalination plant is constructed near a coast to secure drinking water. In addition, seawater is, for example, raw water for treatment in a salt production plant, and in this type of seawater treatment facility, it is necessary to introduce seawater to a device for desalinating seawater or the like.

[0003] Therefore, in such a seawater treatment facility, seawater is conventionally taken in by a nonwoven fabric wound around a polyvinyl chloride pipe formed through a large number of water intake holes, or by an intake tunnel in which a perforated fume pipe is buried. .

However, since the intake tunnel having such a configuration is buried by the open-cutting method or the burial method, there are many restrictions on construction due to the fact that the area immediately above the burying position is exclusively used for burying work.

Therefore, the present inventors have developed a technique for constructing this kind of intake tunnel by a shield method, and have already proposed it in Japanese Patent Application No. 9-218492. The segment used in this construction method is one in which a water-permeable member is attached to the outside of a skin plate, such as a steel segment or a ductile segment, which has been conventionally used in a normal shield method, and is integrated.

[0006] The water permeable member is made of porous concrete or the like, and has a structure in which groundwater or the like that has passed through the water permeable member is actively taken in from a water intake hole provided in the skin plate.

In the segment configured as described above, the lining member that supports the external pressure (earth pressure, water pressure, etc.) acting on the tunnel is a structural part such as steel or ductile, and the water permeable member is basically a permeable member. Should have a strength that can withstand compression by external pressure.

However, such a segment for an intake tunnel has the following technical problems.

[0009]

That is, a large shearing force or moment due to external pressure acts on the water permeable member of the segment having the above-described structure.
The higher the water permeability, the more or larger the holes in the member, and the lower the strength.

However, in order to increase the shear strength of the water-permeable member, the number of holes in the member must be reduced or the diameter of the hole must be reduced. There was a problem that sex had to be sacrificed.

The present invention has been made in view of such problems, and it is an object of the present invention to improve water intake performance by securing water permeability and to increase shear strength. To provide a segment for an intake tunnel.

[0012]

In order to achieve the above object, the present invention relates to an intake tunnel segment assembled cylindrically inside a digging surface excavated by a shield machine, wherein the intake tunnel segment is , a predetermined length of the cylindrical body comprises a plurality of segments units divided along the circumferential direction of the segment unit includes a segment body which is interconnected in the circumferential and axial direction, said segments
A plurality of mounting holes provided at predetermined intervals along a circumferential direction of the main body, and detachably fixed to the water intake holes,
During the construction of the tunnel, the intake
In addition, after the construction of the intake tunnel,
Te, has a lid for opening the intake hole, a perforated water permeable plate arch or dome shape to cover the outside of the intake holes, and said perforated water permeable plate permeable layer provided on the outside of I have . According to the intake tunnel segment configured as described above, the arch or dome-shaped perforated water-permeable plate that covers the outside of the water intake hole is provided, and the water-permeable layer is provided outside this, so that external pressure acts on the water-permeable layer. In this case, the arch or dome-shaped perforated water-permeable plate opposes the external pressure, so that no shear force acts on the water-permeable layer. In addition, the perforated perforated plate in the shape of an arch or a dome is reduced in strength by providing holes, but is advantageous to external pressure due to the arch or dome effect,
The member thickness can be smaller than that of a flat plate.
The perforated water-permeable plate can be selected from a metal plate, a stainless steel plate, and a plastic plate subjected to a rust-preventive treatment with a predetermined thickness. , Can be used for a long time. The water permeable layer are open cells member filled in the recess formed in the segment body, it can be selected porous concrete or al.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. 1 and 2 show an embodiment of the intake tunnel segment according to the present invention.

The segment 10 shown in FIG. 1 is assembled in an annular shape by fastening bolts and nuts inside the excavated surface excavated by the shield machine, as shown in FIG. And four segment units 12 obtained by dividing a cylindrical body of a predetermined length into four along the circumferential direction.

The segment unit 12 is assembled annularly by connecting bolts and nuts that are adjacent to each other in the circumferential and longitudinal directions in the same manner as the segment used in the conventional shield method. In
A sealing material and a caulking material (not shown) are interposed.

Each segment unit 12 includes a segment main body 12a, a permeable layer 12b, a water intake hole 12c, a lid 12d, and a perforated permeable plate 12e.

The segment main body 12a is made of a cast iron plate or a steel plate. A pair of connecting flanges 120a are provided at both ends in the longitudinal direction, and a concave portion 121a depressed inward is formed on an outer peripheral surface between the flanges 120a. Are formed. The water intake holes 12c are located on the center of the concave portion 121a, are formed through the flat bottom surface, and are provided at predetermined intervals along the circumferential direction. In the case of the present embodiment, The segment main body 12a is provided integrally with the main body 12a by forming a through hole and extruding the periphery thereof outward.

The lid 12d is detachably screwed and fixed to the water intake hole 12c.
12c is closed, and the water intake hole 12c is opened by attaching and detaching the lid 12d after the construction of the water intake tunnel.

The perforated water permeable plate 12e is provided so as to cover the outside of the water intake hole 12c. In the case of the present embodiment, the cross section has an almost semicircular arch shape.
A space is formed on the outer periphery of c.

The perforated water-permeable plate 12e is provided with a number of through holes (not shown) in the thickness direction thereof.
This imparts water permeability.

Further, in the case of the present embodiment, the perforated water-permeable plate 12e goes around the outer periphery when the segment 10 is assembled in a cylindrical shape. This perforated water-permeable plate 1
2e is made of, for example, a metal plate, a stainless steel plate, a plastics plate or the like, which has been subjected to a rust-proofing treatment of a predetermined thickness.

When the above-mentioned metal plate or stainless steel plate is used for the perforated water-permeable plate 12e, these can be fixed to the outer peripheral surface of the concave portion 121a of the segment body 12a by welding. Can be similarly fixed with an adhesive.

The perforated water-permeable plate 12 using the above plate material
According to e, rust can prevent the through-hole from being blocked, and can be used for a long time without impairing the water permeability of the water-permeable plate 12e.

The water-permeable layer 12b is a porous body having a large number of continuous voids and having water permeability, and is selected from, for example, an open-cell member or porous concrete, and is provided on the outer side of the perforated water-permeable plate 12e. Is filled and solidified in the concave portion 121a.

In the segment 10 of this embodiment,
A filter material such as a nonwoven fabric may be attached to the entire outer peripheral surface of the water-permeable layer 12b.

According to the segment 10 configured as described above, the arch-shaped perforated water-permeable plate 12e that covers the outside of the water intake hole 12c is provided, and the water-permeable layer 12b is provided outside this. When external pressure acts on the permeable layer 12b,
The shear strength of the water-permeable layer 12b is increased by the arch-shaped perforated water-permeable plate 12e opposing the external pressure.

Therefore, in the segment 10 of the present embodiment, it is possible to increase the number of holes in the member and increase the hole diameter to increase the water permeability without sacrificing the water permeability of the water-permeable layer 12b. Will be possible.

The arch-shaped perforated water-permeable plate 12e is
Although the strength is reduced by providing the holes, the arch effect is advantageous against external pressure, and the member thickness can be made smaller than that of a flat plate.
Since b may be reduced, the weight may be reduced.

FIG. 3 shows another embodiment of the intake tunnel segment according to the present invention. The same or corresponding parts as in the above embodiment are denoted by the same reference numerals, and the description thereof will be omitted. Hereinafter, only the characteristic points will be described.

In the embodiment shown in FIG.
e ′ is formed in a dome shape, and a dome-shaped perforated water-permeable plate 1 is formed.
By 2e ', the outside of the water intake hole 12c is individually covered.

In the segment 10 configured as described above,
A permeable layer 12b is provided outside the dome-shaped perforated permeable plate 12e '.
Is provided, the same operation and effect as in the above embodiment can be obtained.

[0032]

As described above in detail in the embodiments,
According to the segment for the intake tunnel according to the present invention, the use of the perforated perforated plate in the shape of an arch or a dome increases the shear strength of the permeable layer. Nature can be secured.

[Brief description of the drawings]

FIG. 1 is a perspective view of an assembled state showing one embodiment of an intake tunnel segment according to the present invention.

FIG. 2 is a sectional view of a main part of FIG.

FIG. 3 is an assembled perspective view showing another embodiment of the intake tunnel segment according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 segment 12 segment unit 12a Segment main body 120a Flange 121a Concave part 12b Water permeable layer 12c Water intake hole 12d Lid 12e Perforated water permeable plate

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-5-156900 (JP, A) JP-A-58-24040 (JP, A) JP-A-63-247432 (JP, A) 10439 (JP, B1) (58) Fields investigated (Int. Cl. ⁷ , DB name) E03B 3/00, 3/04 E21D 11/04, 11/14 E21D 9/06

Claims (3)

(57) [Claims] 1. An intake tunnel segment assembled cylindrically inside an excavation surface excavated by a shield machine, wherein the intake tunnel segment is formed by dividing a cylindrical body having a predetermined length along a circumferential direction. A segment body, which is connected to each other in the circumferential and axial directions, at a predetermined interval along the circumferential direction of the segment body.
A plurality of mounting holes, and detachably fixed to the water intake hole to construct a water intake tunnel.
Inside, the intake hole is closed and the intake tunnel
Is desorbed from the intake hole after the construction of the intake hole, and the intake hole is
Wherein a lid body for opening, said a perforated water permeable plate arch or dome shape to cover the outer water intake bore, and this <br/> having said perforated water permeable plate permeable layer provided on the outside of Intake tunnel segment. Wherein said perforated water permeable plate is a metal plate that rust has been performed a predetermined thickness, stainless steel plate, according to claim 1, wherein the selected plastic plate or <br/> et al Segment for intake tunnel. Wherein the water-permeable layer has been open cells member filled in the recess formed in the segment body, intake tunnel according to claim 1, characterized in that it is selected from porous Con <br/> Cree DOO Segment.