JP2674482B2 - Lining method in shield method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lining method in a shield method.

[0002]

2. Description of the Related Art As a lining method in the shield method, there are known a normal method of assembling segments and lining the excavation inner surface and a method of placing concrete directly on the excavation inner surface and lining.

[0003]

In the construction method using segments, since the deeper the depth in a geological site where the groundwater level is high and the water permeability is large, the pressure resistance of the tail seal and backfill injection become more uncertain. It is said that construction is difficult. In addition, in the method of directly placing concrete and lining the concrete, which has not yet solidified directly contacts the ground, there is concern about the quality of the lining on soft ground.

[0004]

SUMMARY OF THE INVENTION The present invention relates to a lining construction method which solves the problems of the conventional method and can be reliably constructed even under high water pressure, and has an opening portion having a valve that opens only on the inner side. And an annular bag each having an opening with a valve that opens only on the outer side are installed along the inner peripheral surface of the skin plate of the shield tail section, and air is pressed into the bag to inflate it and the outer peripheral surface of the bag. After making it adhere to the inner peripheral surface of the skin plate,
Advance the shield machine to separate the bag from the skin plate,
Pouring concrete into the bag through the opening while the outer surface of the bag is in close contact with the ground and the inner surface of the bag is in close contact with the outer surface of the steel cylinder attached to the shield machine body. Is a lining method in the shield method.

The first point of the present invention is that a pressure-resistant annular bag is used in the construction of the lining. The annular bag has an opening with a valve that opens only on the inner side and an opening with a valve that opens only on the outer side. The valve that opens only on the inner side is used for air pressure injection and concrete injection, and the valve that opens only on the outer side increases the internal air pressure during concrete injection to allow concrete injection. This is for discharging air when the internal air pressure exceeds a predetermined value so as not to hinder the air.
Since the annular bag after installation is inflated with high-pressure air, it can withstand even high water pressure and acts as a support for the excavation surface in cooperation with the steel cylinder and other supports, and inside the shield machine during construction. Prevent water and gas from entering. After the concrete is poured into the ring-shaped bag and the concrete is hardened, the ring-shaped bag becomes a part of the concrete lining. This pressure-resistant annular bag is manufactured, for example, by using a sheet of rubber or plastic and synthetic fibers of high strength and arranging the synthetic fibers in an oblique lattice pattern and laminating the sheets, and the cross-sectional shape is It is usually rectangular to increase the contact area with the excavation surface.

The second main point of the present invention is that a steel cylinder is attached to the tail of the shield machine via a beam. The steel cylinder is for supporting an annular bag separated from the skin plate from the inner peripheral surface side of the bag, and is fixed around several beams by welding or the like. These several beams are for connecting steel cylinders to the shield machine main body, but a movable connecting portion is provided in the middle to install new annular bags at predetermined positions one after another.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings.

FIGS. 1 (a) and 1 (b) show a typical closed type annular bag 1 used in the present invention. FIG. 1 (a) is a vertical sectional view in the excavating direction, and FIG. 1 (b) is A- in FIG. FIG.

1 (c) and 1 (d) show another closed type annular bag 1 used in the present invention, and FIG. 1 (c) is a longitudinal sectional view in the excavating direction,
(D) is a view on arrow AA of (c).

The annular bag 1 shown in FIGS. 1 (a) and 1 (b) is a closed type in which the bag is closed at the time of installation and is made of a rubber or plastic sheet and is reinforced with a synthetic fiber reinforcement 4. The outer diameter of the annular bag 1 is about the same as the inner diameter of the skin plate 18 of the shield machine, the cross section is rectangular, and the extension 2 is formed on the outer peripheral surface. This extension 2
Part of the outer peripheral surface 3 of the annular bag 1 to be installed next on the inner peripheral surface of the
Since they are submerged and joined together, the joining surfaces 5 of the two annular bags 1 are each finished to be a rough surface. When joining the two annular bags 1, the joining surface 5 and the front and back joining surfaces are bonded as necessary. On the other hand, the outer peripheral surface of the annular bag 1 is crimped to the skin plate 18 and the inner peripheral surface thereof is crimped to a steel cylinder 19 described later, but as the excavation progresses, the skin plate 18 and the steel cylinder 19 move in the excavating direction. Since it moves, in order to prevent the annular bag 1 from being dragged during this movement, it is preferable that the outer peripheral surface and the inner peripheral surface of the annular bag 1 are smooth surfaces, and lubricant is applied to these surfaces as necessary. . In short, it is preferable that the annular bags 1 are firmly connected to each other and the annular bag 1 and the skin plate 18 or the steel cylinder 19 are made slippery in the excavating direction.

The annular bag 1 shown in FIGS. 1C and 1D is also a closed type in which the bag is closed at the time of installation.
The structure and shape are almost the same as those of (a) and (b), but the difference is that a through hole 6 penetrating in the direction of excavation is provided. By using the through holes 6 to insert concrete reinforcing bars and sequentially expanding them by welding or the like, it becomes possible to arrange the reinforcing bars of concrete to be placed later when the annular bag 1 is installed.

FIG. 2 shows an open type annular bag 1 used in the present invention.
(A) is a longitudinal sectional view of the annular bag 1 alone in the excavation direction,
(B) is a longitudinal sectional view in the excavating direction when the annular bag 1 is connected.

The annular bag 1 shown in FIG. 2 is an example of an open type in which the bag is opened before installation and closed at the time of installation, and the constituent material and the reinforcing material are the same as in the case of FIG. Ring bag 1
Is a structure in which the side wall portion 8 having a slightly wider width, the side wall portion 9 having a slightly smaller width, and the partition wall portion 7 have a rectangular cross section and both ends of the side wall portion 8 and the side wall portion 9 are open when viewed in a vertical cross section in the excavation direction. ing. As shown in (b), at the time of installation, the slightly narrow side wall portion 9 is fitted inside the slightly wide side wall portion 8 of the existing annular bag 1 and the fitting surface is adhered to the existing annular bag 1. The open end of 1 is closed, and the existing annular bag 1 becomes the closed annular bag 1. By using the open type annular bag 1, it becomes possible to enclose a concrete reinforcing material such as a reinforcing cage in the annular bag 1 during installation. When the groundwater pressure is particularly high, when the open type annular bag 1 is installed, another annular pipe 10 is incorporated inside the annular bag 1 as shown in (b).
It is also conceivable to make the inside of 0 especially high to cope with groundwater pressure.

3A and 3B show an opening and a valve provided in the annular bag 1, wherein FIGS. 3A and 3B are longitudinal sectional views in the annular direction of the annular bag 1, and FIG. An opening 14 having a valve 13 that opens only inwardly inside the top of the annular bag 1
And an opening 12 with a valve 11 that opens only on the outside. The opening portion 14 is used for press-fitting air and pouring concrete, and the opening portion 12 is for discharging air when the internal air pressure becomes a predetermined value or more during pouring concrete. Is. Holes are made in the steel cylinder 19 to be described later at positions corresponding to the openings 14 and 12, and concrete is injected and air is discharged through the holes.

FIG. 4 uses a typical closed annular bag 1,
Also, the installation of the reinforcing material when it is necessary to reinforce the lining concrete with the reinforcing material is illustrated in (a)-
Each of (d) is a vertical cross-sectional view of the annular bag 1. The reinforcing member 15 in the ring direction is installed by sandwiching the preformed annular reinforcing bar or steel frame at the joint surface between the existing annular bag 1 and the annular bag 1 when the annular bag 1 is installed. (A) shows one rebar
(B) is a bundle of two reinforcing bars, (c) is a shape steel, and reinforcement 1
5 is an example used as 5. Since the reinforcement 16 cannot be installed in the excavation direction before pouring the concrete, as shown in (d), after the concrete hardens, the reinforcement 16 such as a steel bar is inserted by making an oblique hole in the concrete as close as possible to the excavation direction. Then, inject mortar etc. and fix.
If the reinforcing member 16 is embedded in an oblique direction opposite to the direction shown in (d), the rear end of the reinforcing member 16 can be used as a fulcrum for reaction force reception for propelling the shield machine.

With reference to FIG. 5, a description will be given of a standard construction procedure using the standard shield machine and the typical closed type annular bag 1 for implementing the present invention.

FIG. 5 shows a standard shield machine 17 and a ring-shaped bag 1 in which the present invention is applied using a typical closed-type ring-shaped bag 1. FIG. (A) is an A-A sectional view of (a), (c) is a BB sectional view of (a), (d) is a CC sectional view of (a), and (e) is a D- of (a). D sectional view, (f) is an EE sectional view of (a), (g)
[Fig. 4] is an enlarged view of an F portion in (a).

The steel cylinder 19 is composed of several steel cylinder side beams 2.
It is welded around 0B and is attached to the shield machine 17 via the beam connecting portion 20C and the shield machine side beam 20A, and the steel cylinder 19 projects rearward from the skin plate 18 of the shield machine 17. Beam connection part 20C
Is composed of a connecting steel material and a connecting tool such as a bolt, except when the annular bag 1 is newly installed, the steel cylindrical side beam 20B,
The shield machine side beam 20A is fixedly connected to each other, but when the annular bag 1 is newly installed, one of the connecting tools is removed and the connecting steel material is rotated, or both connecting tools are removed to remove the connecting steel material. It has a structure in which a gap necessary for installing the annular bag 1 is produced by removing the annular bag 1. A cylindrical reaction force receiver 21 is installed behind the steel cylinder 19.
Several hydraulic jacks 22 are installed in the middle. The reaction force receiver 21 also serves as a supporting work until the concrete in the annular bag 1 reaches a required strength, and transmits the reaction force to the lining concrete by a frictional force with the lining concrete or the like.
In order to increase this frictional force, a small protrusion or the like is attached to the outer peripheral surface of the reaction force receiver 21 as necessary, and a jack or the like is used to allow the reaction force receiver 21 to move forward to some extent in the radial direction. The structure will allow displacement.

A standard construction procedure using the closed typical annular bag 1 will be described below.

(1) The hydraulic jack 22 is operated to extend the arm 23 to propel the shield machine 17. The existing annular bag 1 begins to separate from the skin plate 18, the outer peripheral surface of the annular bag 1 apart from the skin plate 18 comes into contact with the excavation surface and plays a role of supporting work, and the inner peripheral surface starts to be supported by the steel cylinder 19. .

(2) Release the connection of the beam connecting portion 20C,
A gap is made between the steel cylindrical side beam 20B and the shield machine side beam 20A, and the annular bag 1 is newly installed from the gap, and air is pressed into the skin plate 18 through the opening 14 and brought into close contact with the skin plate 18. In parallel with this, the steel cylinder 1 is attached to the annular bag 1 reaching a predetermined position on the steel cylinder 19.
Through the hole (not shown) provided in 9 and the opening 14, compaction unnecessary concrete is poured into the annular bag 1. On this occasion,
When the air pressure in the annular bag 1 exceeds a predetermined value, the opening 12,
Air is exhausted through a hole (not shown) provided in the steel cylinder 19, and concrete is sufficiently injected into the annular bag 1. As the concrete, fiber reinforced concrete is used if necessary.

(3) The hydraulic jack 22 is operated to retract the arm 23, and the reaction force receiver 21 is drawn toward the shield machine 17 side.

The annular bags 1 are sequentially assembled by repeating (1) to (3). Concrete in the annular bag 1 is a steel cylinder 1
9. While passing through the reaction force receiver 21, it hardens and develops a required strength.

According to the present invention, since the lining concrete is formed by directly contacting the annular bag 1 with the natural ground, it is not necessary to inject the backfill concrete as in the segment construction method.
When the backfill concrete is positively injected into the clearance of the ground for special circumstances, the same valve 11 and opening 12 as those in FIG. 3A are used.
This can be dealt with by providing the ring bag 1 also on the outer peripheral surface side and setting the set pressure lower than that on the inner peripheral surface side.

[0025]

【The invention's effect】

(1) It is possible to perform construction under high water pressure that conventional tail seals cannot withstand.

(2) It is possible to prevent gas from entering the shield machine, which cannot be prevented by the conventional tail seal.

(3) Backfilling is not necessary.

(4) It is possible to prevent the concrete from flowing around to the face of the face due to the outflow of concrete into the overhang.

(5) Since the lining concrete hardens under high pressure in the annular bag, its strength increases.

(6) In the case of soft ground, the necessity of constructing auxiliary work for solidifying the ground and lowering the groundwater level is reduced.

(7) Since rubber or plastic intervenes in the lining, it becomes a flexible lining and the earthquake resistance is improved.

[Brief description of the drawings]

FIG. 1 shows a closed annular bag used in the present invention,
(A), (b) shows a typical closed annular bag, (a)
Is a vertical cross-sectional view in the excavation direction, and (b) is a view taken along the line AA of (a). (C) and (d) show another closed type annular bag,
(C) is a longitudinal cross-sectional view in the excavation direction, and (d) is a view taken along the line AA of (c).

FIG. 2 shows an open type annular bag 1 used in the present invention,
(A) is a longitudinal sectional view of the annular bag 1 alone in the excavating direction, and (b) is a longitudinal sectional view of the annular bag 1 when the annular bag 1 is connected.

FIG. 3 shows the openings and valves provided in the annular bag,
(A), (b) is a ring direction vertical cross section of an annular bag, (c) is an excavation direction vertical cross section.

[Fig. 4] Fig. 4 illustrates installation of a reinforcing material when a closed type typical annular bag is used and the lining concrete needs to be reinforced with the reinforcing material, in which (a) to (d) are any ones. FIG. 3 is a vertical sectional view of an annular bag.

FIG. 5 shows a standard shield machine and an annular bag in which the present invention is constructed using a closed typical annular bag,
(A) is a vertical cross-sectional view in the excavation direction, (b) is an AA cross-sectional view of (a), (c) is a BB cross-sectional view of (a), (d) is (a).
CC sectional view of (a), DD sectional view of (a),
(F) is an EE sectional view of (a), and (g) is an enlarged view of the F portion of (a).

[Explanation of symbols]

1 ... annular bag, 2 ... outer peripheral surface extension, 3 ... outer peripheral surface joining part, 4 ... synthetic fiber reinforcement, 5 ... annular bag joining surface,
6 ... through hole, 7 ... partition wall, 8 ... wide side wall,
9 ... Narrow side wall, 10 ... Annular pipe, 11 ... Valve that opens only on the outside, 12 ... Discharge opening, 13 ... Valve that opens only on the inside, 14 ... Opening, 15 ・ ・ Concrete reinforcement, 16 ・ ・ Steel bar, 17 ・ ・ Shield machine,
18 ・ ・ Skin plate, 19 ・ ・ Steel cylinder, 20A ・
・ Shield machine side beam, 20B ・ ・ Steel cylinder side beam,
20C ··· beam connecting part, 21 ··· reaction force receiving, 22 · · hydraulic jack, 23 · · jack arm.

Claims (1)

(57) [Claims] 1. An annular bag provided with an opening having a valve that opens only on the inner side and an opening having a valve that opens only on the outer side is installed along the inner peripheral surface of the skin plate of the shield tail. Then, press the air into the bag to inflate it to bring the outer peripheral surface of the bag into close contact with the inner peripheral surface of the skin plate, and then move the shield machine forward to separate the bag from the skin plate so that the outer peripheral surface of the bag comes into close contact with the ground. A lining method in a shield construction method characterized in that concrete is poured into the bag through an opening while the inner peripheral surface of the bag is in close contact with and is sandwiched by the outer peripheral surface of a steel cylinder attached to the shield machine body.