JP2832285B2 - Open shield method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to an open shield method for constructing underground structures such as water and sewage, common ditches, telegraphs, telephones, and other laid underpasses in urban areas.

[Conventional technology]

The open shield method is the open-cut method (open method)
It is a construction method that is highly rational, taking advantage of the advantages of the shield construction method.

FIG. 5 and FIG. 6 schematically show an open shield machine 1 comprising left and right side walls 1a and 1b and a bottom plate 1c connecting between the side walls 1a and 1b. It is a type shield machine.

The open shield machine 1 includes a propulsion jack 2 and a side wall plate 1.
They are arranged side by side vertically rearward inside a and 1b. 3 in the figure
Indicates a partition provided in the shield machine 1.

Although not shown, the shield machine 1 is installed in the start pit, and the earth and sand in front of the start pit is excavated from the front or top opening of the shield machine 1 and discharged. Then, the propulsion jack 2 of the shield machine 1 is extended and the shield machine 1 is advanced by applying a reaction force to the reaction wall in the starting pit, and the concrete box 4 is moved.
The first underground structure is suspended from above and set in the tail portion 1d of the shield machine 1 behind the contracted propulsion jack 2.

Next, the excavating means 12 such as a shovel, an auger, and a bucket excavates earth and sand from the front surface or the upper surface of the shielding machine 1 and discharges the earth to advance the shielding machine 1 to the front of the first concrete box 4. Then, the second concrete box 4 is suspended. Hereinafter, the same excavation and setting steps of the concrete box 4 are repeated, and the concrete boxes 4 are sequentially buried in the ground in a column to form an underground structure, and the backfill 5 is placed on the rear underground structure. When the open shield machine 1 reaches the reaching pit, it is removed and the construction is completed.

In addition, when the concrete box 4 is suspended and set, a rectangular frame 11 slightly larger than the outer circumference of the end face of the concrete box 4 is hung so as to abut on the front end face of the concrete box 4. When the propulsion jack 2 pushes the push bar 11, it is considered that a reaction force can be uniformly obtained over the entire front end of the concrete box 4.

By the way, when the concrete box 4 is installed in the shield machine 1, a gap always occurs between the shield machine 1 and the box 4. Further, when the shield machine 1 moves forward and the concrete box 4 is left in the ground, tail voids of the side walls 1a and 1b and the bottom plate 1c are generated. A grout is required to prevent the concrete box 4 from sinking due to such a gap.

As the grouting method, the following method has been adopted.

First, the concrete box 4 is hung on the bottom plate 1c of the tail part 1d of the shield machine so as to be supported by a height adjusting member 10 of a block body made of mortar, wood, metal or the like.

This height adjusting material 10 is composed of a concrete box 4 and a tail part.
A gap is secured between the bottom plate 1c of the concrete box 1d and the sealing material 7 is filled in the gap between the outer peripheral front end of the concrete box 4 and the tail portion 1d, and the (primary) grout material 6 is placed behind the sealing material 7. Fill.

When the shield machine 1 is advanced after the grout material 6 has hardened, the concrete box 4 whose outer periphery is covered with the grout material 6 except for the upper surface remains in the ground. Next) grout material 6 'is filled.

[Problems to be solved by the invention]

As the sealing material 7, a sponge material using a waste material of a mattress or the like is used as a disposable material, and the sponge material is filled in a gap between the vicinity of the outer peripheral front end of the concrete box 4 and the tail portion 1d for sealing.

However, waste mattresses are not hygienic and are difficult to obtain because hundreds of them are used at one construction site.

On the other hand, using a new sponge material or a styrofoam material or rubber material instead of the sponge material results in extremely high cost.

In addition, the sponge material, styrofoam material, and rubber material are not limited to the old and new ones, but are manually packed by an operator, and require time and labor. 1 is wetted to the front and cleaning it is difficult.

An object of the present invention is to solve the inconvenience of the conventional example described above, and to provide an open shield method capable of performing a primary grout by sealing a gap between a concrete box and a shield machine tail portion easily and reliably without troublesome work. To provide.

[Means for solving the problem]

In order to achieve the above object, the present invention provides a propulsion jack in a shield machine with open front and rear ends and an upper surface, excavates from the front surface or the front upper surface of the shield machine, and reacts an existing underground structure by a subsequent concrete box. The shield machine is advanced by the propulsion jack, and a new concrete box is suspended from the rear upper surface of the shield machine at this advance, and is positioned in the front row of the existing underground structure. In the open shield method, the concrete box suspended inside the shield machine is supported under the bottom plate with a height adjusting material and the front end of the outer periphery A tube that can be expanded with gas or liquid is wound around it, and the tube is expanded to seal the gap between the concrete box and the shield machine. It is an Abstract that grout.

[Action]

According to the present invention, the tube can be set on the outer periphery of the concrete box and then inflated by injecting gas or liquid into the inside, whereby the gap between the concrete box and the shield machine tail part 1 can be completely closed.

Also, if gas or liquid is released from the tube after grouting, the tube shrinks, so that the tube can be removed from the concrete box, pulled up, and reused.

〔Example〕

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

1 is a vertical sectional side view showing one embodiment of the open shield method of the present invention, FIG. 2 is a cross-sectional plan view of the same, FIG. 3 is a vertical sectional front view, and FIG. 5 and FIG. The same components as those described above are denoted by the same reference numerals.

First, the sealing material used in the method of the present invention will be described.

As shown in FIG. 4, the sealing material is formed by a tube 8 which can be expanded by gas or liquid, and is a cylindrical concrete box having a top plate 4a, left and right side plates 4b, and a bottom plate 4c and penetrating sideways. The body 4 has a length sufficient to wind the outer circumferences of the side plate 4b and the bottom plate 4c in the circumferential direction.

 The tube 8 was formed with an inlet 8a.

The material of the tube 8 is preferably a material that can expand and contract, such as rubber, but may be a material that does not expand and contract itself as long as it is highly flexible, such as vinyl.

Next, the method of the present invention using such a tube 8 as a sealing material will be described.

The outline of the entire open shield method is the same as that of the conventional example.

That is, the shield machine 1 is installed in the start pit, and the earth and sand in front of the start pit is excavated and discharged from the front or top opening of the shield machine 1. Then, the propulsion jack 2 of the shield machine 1 is extended and the shield machine 1 is advanced by applying a reaction force to the reaction wall in the starting mine, and the first underground structure by the concrete box 4 is suspended from above. And shield machine 1
Of the propulsion jack 2 which has been contracted in the tail part 1d.

Next, the excavating means 12 such as a shovel, an auger, and a bucket excavates earth and sand from the front surface or the upper surface of the shielding machine 1 and discharges the earth to advance the shielding machine 1 to the front of the first concrete box 4. Then, the second concrete box 4 is suspended. Hereinafter, the same excavation and setting steps of the concrete box 4 are repeated, and the concrete boxes 4 are sequentially buried in the ground in a column to form an underground structure, and the backfill 5 is placed on the rear underground structure. When the open shield machine 1 reaches the reaching pit, it is removed and the construction is completed.

When the concrete box 4 is suspended from above and set behind the propelled jack 2 contracted in the tail portion 1d of the shield machine 1, the concrete box 4 is supported by the height adjusting member 10, but at the same time, The tube 8 is arranged in a gap between the outer peripheral front end of the concrete box 4 and the tail portion 1d.

The tube 8 may be installed in the shielding machine 1 before the concrete box 4 is suspended, or the tube 8 may be mounted on the concrete box 4 in advance and suspended in the shielding machine 1 together. Alternatively, the tube 8 may be passed through a gap between the concrete box 4 and the shield machine 1 after the concrete box 4 is installed.

Inject compressed air with an air compressor placed on the ground
When the tube 8 is fed into the tube 8 from 8a, the tube 8 expands and completely closes the gap with the tail portion 1d.

After this, the (primary) grout material 6 is filled in the rear.

If the air in the tube 8 is evacuated from the inlet 8a after the grout material 6 has hardened, the tube 8 returns to its original state of contraction, and is removed from the concrete box 4 and pulled up to the ground.

Thereafter, when the shield machine 1 is moved forward, the concrete box 4 whose outer periphery is covered with the grout material 6 except for the upper surface remains in the ground.
Next) grout material 6 'is filled.

Although air is used to expand the tube 8 in the above embodiment, the tube 8 may be expanded with a liquid such as water.

In addition, it is better to suspend and set the pusher 11 so as to be in contact with the front end face of the concrete box 4 before setting the tube 8 and expanding it. However, the pusher 11 is provided first. It is also possible to set the tube 8 from.

〔The invention's effect〕

As described above, the open shield method of the present invention
The gap between the concrete box and the tail part of the shield machine can be completely and easily sealed without troublesome primary grouting. The sealing material is removed from the concrete box and pulled up for reuse. Therefore, the cost can be reduced.

[Brief description of the drawings]

1 is a longitudinal sectional side view showing one embodiment of the open shield method of the present invention, FIG. 2 is a cross-sectional plan view of the same, FIG. 3 is a vertical front view of the same, FIG. The figure is a longitudinal side view showing a conventional example, and FIG. 6 is a cross-sectional plan view of the same. 1 Open shield machine 1a, 1b Side wall plate, 1c Bottom plate 1d Tail, 2 Propulsion jack 3 Partition wall 4, Concrete box 4a Top plate, 4b side Face plate 4c Bottom plate 5 Backfill, 6, 6 'Grout material 7 Sealing material 8, Tube 8a Injection port 10 Height adjusting material 11, Square bracket 12 … Excavation means

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Hiroshi Kawakami 4-9-9 Akasaka, Minato-ku, Tokyo Inside Soil Development Co., Ltd. (72) Inventor Shigetoshi Ishida 1-6-5 Nihonbashi Honcho, Chuo-ku, Tokyo No. Maruto Sheet Pile Co., Ltd. (72) Inventor Tatsuhiro Kamedaya 1-6-5, Nihonbashi Honcho, Chuo-ku, Tokyo Maruto Sheet Pile Co., Ltd. (56) References JP-A-3-169915 (JP, A JP-A-2-209594 (JP, A) JP-A-2-49896 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) E21D 9/06 331

Claims (1)

(57) [Claims] A propulsion jack is provided in a shield machine having open front and rear ends and an upper surface. The propulsion jack is excavated from a front surface or a front upper surface of the shield machine. Move the machine forward, suspend a new concrete box from the rear upper surface of the shield machine in the advance, position it in the front row of the existing underground structure, repeat the same process and excavate the shield machine, In the open shield method where the upper and side surfaces of the existing underground structure are appropriately buried, the concrete box suspended inside the shield machine is supported under the bottom plate with a height adjusting material,
An open shield in which a tube expandable with gas or liquid is wound around the front end of the outer periphery, the tube is expanded to seal the gap between the concrete box and the shield machine, and grout is injected behind it. Construction method.