JPS60181496A - Shield tunnel construction method and apparatus - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for continuously covering the outer periphery of a shield segment with an impermeable membrane when excavating a tunnel by the shield tunnel method, and an apparatus for implementing the method.

The shield tunnel method is used to excavate tunnels in highly collapsible soil by using a strong steel shell called a "shield excavator" that has a cross section slightly larger than that of a tunnel top to excavate underground. This is a method of constructing a tunnel by safely performing excavation work and segment assembly work while preventing the collapse of earth and sand inside.

To implement the above construction method, there are various types of shields, pattern shields, closed shields, closed shields, etc., depending on the type of soil involved, but these are all related to the format of the 111 [i-adic device]. After excavating with a shield, the segment assembly (which is pre-fabricated as a segment) is assembled and constructed at the rear of the excavator to support the ground to which the tunnel structure will be attached. A common method is used in both construction methods.

This segment assembly is carried out in 11J when the shield excavates. To.

This is a construction work in which the shield tunnel is formed by joining the existing segments at the rear to form a shield tunnel.As the segments are assembled in a narrow shield premises, it is difficult to assemble them in a perfect circle, and due to gravity and ground pressure. for Jlil L
Because of this, even if various sealing materials are used at the joints of segments and they are assembled and joined together, gaps may be created, the segments may be misaligned, the joint surfaces may be uneven, or when the segments are transported. It is extremely common for gaps to occur due to various conditions such as slight damage during assembly. Since the shield construction method is often carried out below the groundwater level, water leakage occurs within the tunnel due to the above reasons. Therefore, it is natural to say that in order to prevent this water leakage, a method of sealing the joints between segments with a sealing material, caulking material, etc. has been adopted, but it is not perfect and must be done with great care. Even if
The reality is that water leaks occur after construction.

On the other hand, in the shield method, in order to assemble the segments in a shield excavation machine, it is necessary to use an excavator whose outer diameter is slightly larger than that of the segment outer diameter, so that the remaining gap on the outer periphery of the segment is parallel to the excavation. and then continuously filled with filler material. This filling material fills the leftover voids to prevent collapse and subsidence of the ground above the excavated portion, as well as to prevent groundwater from entering the tunnel. Even with this filling material, cracks may occur in the solidified filler over time, or the filler may be diluted by underground water etc. during filling, so it may not be possible to completely fill the voids. There is also a risk that the filler material may leak to other areas and damage the surrounding groundwater environment. In addition, the amount of filler to be injected is not necessarily the necessary amount to fill the void, as it may concentrate in the soft parts of the ground, be diluted, or be washed away.
At present, it is necessary to use a huge amount of % to 400%.

As mentioned above, when tunnels are constructed using the shield method, there are major problems as described above.

The present inventors have arrived at the present invention as a result of intensive studies aimed at perfecting the prevention of water leakage inside and outside the tunnel and optimizing the amount of filler used. When constructing tunnels using this construction method, segments are assembled at the rear of the shield excavation machine, and an impermeable membrane is continuously coated around the outer periphery of the constructed segments when the newly constructed segments are successively connected to the already assembled segments. Characteristic shield tunnel construction method.

Additionally, a storage device was installed to compress and store the impermeable membrane on the inner peripheral surface of the skin plate of the shield tunneling machine.

It consists of equipment for implementing the shield tunnel method.

The construction method and apparatus using the spider of the present invention will be explained below based on the attached drawings.

FIG. 1 is a cross-sectional view of a main part in the direction of excavation by a shield according to the present invention for explaining one example of the construction method of the present invention.

In Fig. 1, the excavator section 1 of the shield is excavated in the direction of the arrow, and the impermeable membrane 5 is pulled out from the inner periphery of the skin plate 2 at the rear of the excavator section 1, compressed in a stretchable state, and stored. The device is equipped with a ring-shaped membrane storage device, and the device is equipped with an impermeable membrane 5 (the material of this impermeable membrane is synthetic resin, which is good from the viewpoint of flexibility, malleability, and ductility, and from the viewpoint of economic efficiency, I like PVC
1: L < , and since the membrane covers the outer periphery of the segment provided in a circle to prevent the intrusion of groundwater etc. into the tunnel, it is preferably formed or processed into a cylindrical shape, and its thickness is (determined as appropriate depending on various conditions) are compressed and stored.

Note that - The membrane is compressed and stored in a bellows shape or a roll shape.

Any compressed state may be used, such as a folded shape. □ Also, a plurality of propulsion jacks 3 are attached in a ring shape inside the membrane storage device 4 (only two are shown in IA), but the axes of these propulsion jacks 3 are parallel to the longitudinal axis of the shield. The excavator section 1 is moved forward by the action of pressing the segment part, which is provided and has a perfect circular shape with 6+11 segments erected, against the existing segment 7 and by the reaction force of pushing the segment. The operation of this jack is driven by a hydraulic pump or the like installed within the shield.

The state shown in the figure shows the state in which the jack 3 presses the newly assembled perfectly circular lining section, but as the jack rod 3' presses down on the lining section, the excavator section 1 moves forward due to the reaction force. At the same time, the membrane storage device 4 moves forward, so the membrane 5 is pulled out, stretched, and laid on the inner periphery of the skin plate 2. The 21st me 1 is the propulsion jatsugi 3
0 Rondo 3' Gauze: Uh, the inning is JIIIi, and the whole shield is strange; +'JU advances, membrane 5 from membrane storage device 4
The figure shows a state in which the skin plate 2 is pulled out and placed on the inner periphery of the skin plate 2. When 1 model 5 is laid, a new segment b;
, assembled in a perfect circle on the inner surface of the membrane, and then press-bonded to the existing segment by the propelling jack 3 to form a new segment tI covered with the membrane. Therefore, by repeating this process, even if the outer periphery of the segment is continuously covered with the impermeable membrane,
4 will be completed. When replenishing a new ψ membrane, in order to maintain continuity, the new membrane is welded to the end of the membrane in use by heat or adhesive.

The ends may simply be overlapped.

New segment section)! 1' 411, it is sufficient to fill the segment with a pump or the like through the filling hole 8 provided in the segment, and the amount is significantly reduced compared to the conventional method.

In addition, since there is no leakage or dilution of the filler due to infiltration of groundwater, the filler can fully function as a filler.

FIG. 3 is a partial vertical sectional view showing the main part of covering the segment pipe wall with an impermeable membrane for carrying out the construction method according to the present invention, and 4 is located at the rear end of the excavator (not shown). It is a storage device for storing an impermeable membrane 5 provided outside the jack and along the inner circumferential surface of the skin plate 2.
For example, as shown in the figure, the compressed water-impermeable membrane 5 is
It is pulled out from a nozzle hole 9 provided in the tube so as to cover the pipe wall made of the segment 7. The procedure for covering the pipe wall consisting of the segments 7 with the impermeable grouping 5 is based on the method described in detail based on Figs.
The figure shows a state in which a pipe wall consisting of segments 7 (with which the jack road 3' contacts) has been newly installed.

In FIG. 3, 10 thick sole skin plates are provided at the end of the skin plate 2, and the gap between the tail skin plate 10 and the pipe wall is made impervious to water.
A tail seal 11 is provided at the further end of the tail skin plate 10 as shown.

The 5 spread impermeable membranes are held in the 114 bodies, and this allows the next stage, that is, the jack road 3'r'rj
& Push the end of the constructed shield/road wall body to advance the excavator,
Accordingly, the water-impermeable membrane 5 can be easily pulled out from the storage device 4.

FIG. 4 is a partial vertical sectional view showing another embodiment of the main part of covering the segment pipe wall with an impermeable membrane for carrying out the construction method according to the present invention. In this embodiment, the tail skin plate 10 is Unlike the previous embodiment, the tail skin plate 10 is divided into two parts in the longitudinal direction, and the water-impermeable membrane 5 extends through the gap created by the split, and the tail seal 11 provided at the rear end of the tail skin plate 10 is divided into two parts. Four impermeable membranes 5 are laid on the bottom side.

FIG. 5 is a partial longitudinal sectional u:jj diagram showing still another embodiment of the main part of covering the segment l□QB' road wall body with an impermeable membrane for carrying out the construction method according to the present invention.

In this embodiment, the storage device 4 is incorporated into the tail skin plate portion (FIG. 4). Therefore, the water-impermeable membrane 5 is guided to the bottom side of the tail seal 11.

In the 47゛q-built excavator shown in Figs. 4 and 5, the storage device i2 can also be made removable.

Instead of making the impermeable membrane cylindrical, it is also possible to make it into a cylindrical shape by loading it into a plurality of storage devices at the same time, taking out the tanzak-shaped films, and then joining them together.

According to the above, when using the construction method of the present invention, not only can the construction method itself be rationally operated, but also the impermeable membrane can completely prevent groundwater from entering the tunnel or leaking out of the tunnel. Therefore, it is expected to make a great contribution to the rational management of tunnel usage, and as already mentioned above, it will make a great contribution to pollution prevention and control. In addition, as a result, it prevents public damage due to ground subsidence, and if the tunnel is a sewer system, the infiltration of underground water is prevented, so the amount of treated sewage is reduced, resulting in efficient operation of sewage treatment, etc. The effects are immeasurable. There is.

[Brief explanation of the drawing]

Figure 1 shows 11ji in the direction of excavation by the shield according to the present application.
C=j main part diagram, Figure 2 is a partial diagram showing the state in which the excavator is advanced by jacking, and Figure 3 is a partial diagram showing the state in which the excavator is advanced by jacking. FIG. 4 is a partial longitudinal sectional view showing another embodiment of the main part shown in FIG. 3, and 5th figure is a partial longitudinal sectional view showing still another embodiment of the main part shown in FIG. 3. 1... Tunnel machine, 2... Skin plate, 3... Propulsion jack, 3'... Jacket rod, 4... Membrane storage device. , 5...
Impermeable membrane, 6...segments. 7... Existing segment, 8... Filling hole, 9... Nozzle, 10... Tail skin plate, 11... Tail seal applicant People Noboru Oka Yoshitoshi Sano Sakae

Claims (1)

[Claims] (1) In tunnel construction using the shield tunnel method,
A shield excavation machine characterized by assembling segments at the rear of the shield excavation machine, and continuously covering the outer periphery of the segment with an impermeable membrane when newly installed segments are successively connected to the already assembled segments.・Rouet method. -) A storage device was installed to compress and store the impermeable membrane on the inner peripheral surface of the skin plate of the shield tunneling machine. Equipment for implementing the shield tunnel method.