JP2810929B2 - Lining method of shield tunnel - Google Patents

Description

The present invention relates to a method for lining a shield tunnel, and more particularly to a method for lining a shield tunnel with a lining material such as cast-in-place concrete. Shield tunnel lining method.

[Background Art] In a lining method in a shield tunnel, a lining method using cast-in-place concrete usually uses a shield machine having a cylindrical outer shape and uses a cutter device or the like provided in front of the shield machine to ground (ground). ), The surrounding wall of the excavated tunnel is covered with a formwork at a predetermined interval, and concrete is poured between the formwork and the surrounding wall, and the concrete is pressed by the operation of the pressing jack. Then, the process of moving the entire shield machine forward is repeatedly performed.

By the way, in such a construction method, the end frame of the pressing jack is provided with the end frame ring so as to close the space between the formwork and the tunnel peripheral wall, but conventionally, the end frame ring is attached to the rod of the pressing jack. Because of the accompanying movement, curing of the concrete is required until the strength of the concrete is developed, and there has been a problem that the construction time is prolonged.

Therefore, as means for solving such a problem, the prior art has proposed that, each time the formwork is arranged, without fixing the formwork ring to the rod of the pressing jack, the formwork ring is moved between the formwork and the tail section. And a means for pressing the lining material through the wife frame ring by the operation of the pressing jack, and then leaving the wife frame ring on the end face of the newly installed lining wall portion (Japanese Patent Application Laid-Open No. 62-202199). No., “Method of lining a shield tunnel”).

"Problems to be Solved by the Invention" However, the following problems to be solved still remain even by such prior art means.

First, in the prior art means, it is difficult to always maintain the concrete pressure higher than the earth pressure and water pressure of the ground because the frame ring is integrated with the reinforcing steel bar. However, since it is configured to oppose the concrete placing pressure, the concrete pressure may be lower than the ground level when the shield machine is propelled.

Second, since the end frame ring is located between the inner form and the tail plate of the shield machine, it is necessary to make the inner form smaller than the distance between the tail plates in order to cope with meandering of the shield machine, It is difficult to keep the pressure of the concrete above a certain level.

The present invention has been proposed in view of the above-mentioned circumstances, and an object thereof is to be able to cast concrete while always keeping the pressure higher than the earth pressure and water pressure of the ground, and to perform high quality lining. It is an object of the present invention to provide a method for lining a shield tunnel capable of performing the above.

"Means for Solving the Problems" In order to achieve such an object, the present invention provides a method in which a peripheral wall of a tunnel excavated while excavating the ground by a cutter device or the like at a tip of a shield machine is separated by a form at predetermined intervals. A method for covering a shield tunnel in which a covering material is supplied between the formwork and the peripheral wall to cover the inner surface of the tunnel, wherein a tail portion of a skin plate of the shield machine is provided with an outer cylinder. Along with the inner cylinder and the inner cylinder, a plurality of concrete piston chambers for accommodating the extruding piston by forming a plurality of partition walls extending in the radial direction of the skin plate between the outer cylinder and the inner cylinder of the tail portion are provided. The pressure holding jack presses the extrusion piston in the concrete piston chamber so that the pressure of the lining material becomes higher than the earth pressure and water pressure of the ground, and the pressure between the formwork and the surrounding wall. And supplying a lining material to the lining.

Further, in order to achieve the same object, the present invention provides a method for lining a shield tunnel, wherein when the supply pressure of the lining material becomes larger than a set holding pressure of a pressure holding jack, the supply pressure of the lining material is increased. Thus, the pushing piston is moved forward of the shield machine.

According to the shield tunnel lining method of the present invention,
By individually controlling the pressure of the extruding pistons in the plurality of concrete piston chambers formed in the tail section by the pressure holding jacks, the pressure of the lining material in each chamber can be individually controlled. It is possible to easily cope with the difference in the mountain pressure, and it is possible to always keep the pressure of the lining material higher than the earth pressure and water pressure of the ground.
Further, by such an operation, the tail void is reliably filled with the lining material, and there is no possibility of sinking.

Further, when the supply pressure of the lining material is greater than the set holding pressure of the pressure holding jack, the extrusion piston is moved forward of the shield machine by the supply pressure of the lining material. The piston moves to the rear of the shield machine when pushing out the lining material and moves forward when putting the lining material into the piston chamber, so that the pressure in the concrete piston chamber can be kept almost constant even when supplying the lining material. Become.

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

FIG. 1 shows the vicinity of a face of a tunnel in the middle of construction according to the present invention. In the figure, reference numeral 10 denotes a shield machine, which is formed behind the shield machine 10 while excavating a tunnel T to the left with respect to the paper surface by a cutter device 12 provided at the front thereof. Tunnel T
Is covered with a mold 1 at a predetermined interval, a lining material is supplied between the mold 1 and the peripheral wall, and a lining wall W is constructed on the inner surface of the tunnel. The form 1 includes a face plate 1a and a support frame 1b for supporting the face plate 1a. However, a steel segment, a concrete segment, or the like may be used.

Next, the shield machine 10 for performing the tunnel lining method according to the present invention will be described more specifically.
As shown in FIG. 1, this is a cylindrical skin plate 11 forming an outer shell, and a cutter device provided at the front end of the skin plate 11 and rotated by driving means (not shown) to excavate the ground. 12 and a propulsion jack 1 whose base end is connected to a partition plate 11a formed inside the skin plate 11.
It has a basic structure equipped with three.

The tail of the skin plate 11 is a skin plate
An outer cylinder 20 having the same diameter as 11 and constituting a part of the skin plate 11
And an inner cylinder 21 having a smaller diameter than the outer cylinder 20. The outer cylinder 20 and the inner cylinder 21 are formed in a radial direction of the skin plate 11 as shown in FIG. Are connected by a plurality of partition walls 22 extending in the direction. And outer cylinder 20
A plurality (four in the illustrated example) of concrete piston chambers 23 are provided between the inner cylinder 21 and the inner cylinder 21, and an extrusion piston 24 is slidably housed in each of the chambers 23.

As shown in FIG. 3, the push-out piston 24 is formed to have a size that fits tightly in the concrete piston chamber 23 in accordance with the internal shape of the concrete piston chamber 23. As shown in the above partition plate
Multiple pressure holding jacks 25 with base attached to 11a
To slide back and forth. In addition, the pressure holding jack 25 for operating the push-out piston 24 is provided with a relief valve, and when the driving pressure of the lining material becomes larger than the holding pressure of the jack,
The jack is configured to shrink.

As shown in FIG. 3, two seal members 26 are attached to the outer periphery of the pushing piston 24, and the inside of the skin plate 11 and the inside of the concrete piston chamber 23 are provided at the center of the pushing piston 24. A filling hole 24a of a lining material is formed (in the vicinity of the center in the embodiment), and the inner surface of the extrusion piston 24 is connected to the filling hole 24a and connected to a casting pipe 30 of the lining material. A joint 27 is provided.

In the embodiment, the seal member 26 has a configuration in which two lines are provided on the outer periphery of the push-out piston 24, but the present invention is not limited to this example. Further, the arrangement position of the filling hole 24a is not limited to the central portion of the piston 24, but may be another portion.

The filling hole 24a is provided with a blocking mechanism 28 for opening and closing the filling hole 24a, so that the filling hole 24a can be opened and closed as needed. The shut-off mechanism 28
Specifically, is configured by a shutter, a valve, and the like, but may have another configuration as long as it can open and close the filling hole 24a.

A tail packing 29 for preventing leakage of the lining material is provided on the tail-side inner surface of the inner cylinder 21 to be in contact with the outer surface of the mold 1, and between the inner cylinder 21 and the mold 1. Is provided with a clearance G in consideration of workability at the time of curve construction (see FIG. 3).

In FIG. 1, reference numeral 30 denotes a casting pipe for the lining material, and the casting pipe 30 has one end connected to a branch valve 33 connected to a supply pipe 32 of a supply pump 31 for the lining material. The casting pipe itself is formed of a flexible pipe or a telescopic pipe so that it can cope with the movement of the pushing piston 24.

Next, a case will be described in which the shield machine constructed as described above is applied to implement the shield-on-nel lining method according to the present invention.

FIG. 1 shows a state in which tunnel lining is performed by the lining method according to the present invention as the shield machine 10 is excavated.

First, in carrying out the method of the present invention, the extrusion pressure of the pressure holding jack 25 is set to a predetermined value in accordance with the difference in the ground pressure depending on the height (see FIG. 1). The casting pipe 30 is connected to the joint portion 27 of the above, and set so that the lining material can be supplied into the concrete piston chamber 23 through the filling port 24a of the extrusion piston 24 (see FIG. 3).

The concrete piston chamber 23 (the interior of the piston chamber surrounded by the members 20, 21, and 22) must be manufactured with high precision in a factory beforehand and formed so that the sealing member 26 can withstand high pressure. Needless to say.

Also in the method of the present invention, the excavation method of the shield machine 10 is basically performed by using a cutter device at the front end of the skin plate 11 while assembling the form 1 into a cylindrical shape using an erector or the like inside the inner cylinder 21. The ground is excavated at 12, and the propulsion jack 13 is driven by applying a reaction force to the form 1 so that the shield machine 10 is excavated.

However, in the method of the present invention, when the shield machine 10 is excavated, the pressure holding jack 24 is constantly operated to hold the pressure of the lining material (concrete in the embodiment) so as to be higher than the ground pressure Pj. Every time the shield machine 10 excavates for a predetermined length, the lining material is sent from the supply pump 31 to the casting pipe 30, and the lining material is discharged from the filling hole 24 a of the extrusion piston 24 through the casting pipe 30 and the concrete piston chamber 23. The biggest feature is that it is supplied inside.

More specifically, (a) the pressing force of the pressure holding jack 25 of the extrusion piston 24 provided in the concrete piston chamber 23 of the shield machine 10 is adjusted to reduce the concrete pressure Po generated by the action of the extrusion piston 24. While maintaining the peak pressure higher than the peak pressure Pj, while assembling the formwork 1 inside the inner cylinder 21, a reaction force is applied to the formwork 1 assembled inside the inner cylinder 21, and the shield machine 10 is driven by the propulsion jack 13. Excavation is performed, and the ground is excavated by the cutter device 12.

At the same time as the excavation, concrete is filled between the peripheral wall of the tunnel T and the formwork 1 by the extrusion piston 24 while the pressure Po of the concrete is always kept higher than the ground pressure Pj.

(B) Next, if the extrusion piston 24 is positioned on the tail side of the shield machine 10 as the shield machine 10 proceeds, the concrete is directed from the casting pipe 30 toward the concrete piston chamber 23 and the pressure of the pressure holding jack 25 is increased. The concrete is supplied at a pressure higher than that, and concrete is poured into the concrete piston chamber 23.

At this time (when concrete is poured into the concrete piston chamber 23), the extrusion piston 24 receives a force in the direction opposite to the pressing force of the pressure holding jack 25 by the supply pressure of the concrete, but presses the extrusion piston 24. Since the pressure holding jack 25 is provided with a relief valve that shrinks when the jack receives a pressure greater than the set pressure, the extrusion piston 24 moves forward of the shield machine 10 with the supply of concrete, Concrete placement is not hindered.

When the supply of concrete is stopped, the pressing force of the pressure holding jack 25 acts on the pushing piston 24 again, and moves rearward as the shield machine 10 advances.

That is, in the embodiment, the extruding piston 24 moves rearward of the shield machine 10 when extruding concrete, and moves forward when putting concrete in the piston chamber 23, so that the pressure in the concrete piston chamber 23 is increased when concrete is supplied. Has the advantage that it can be kept almost constant.

As described above, by repeating the steps (a) and (b), the inner surface of the tunnel is successively lining with cast-in-place concrete.

During the above process, the sealing member 26 of the pushing piston 24 is
If it is necessary to replace the sealing member 26, the extruding piston 24 may be extracted from the concrete piston chamber 23 after the concrete has hardened, and the sealing member 26 may be replaced.

This operation is performed after the concrete
This is a simple operation of removing the seal member 26 using the pressure holding jack 25 and exchanging the seal member 26 on the outer periphery thereof. Since the exchange operation is performed after the concrete is hardened, it can be safely performed on site.

Further, when it is necessary to clean the concrete pipe, the filling port 24a may be closed using the blocking mechanism 28 attached to the extrusion piston 24, the casting pipe 30 may be removed, and the concrete pipe may be cleaned.

Since this operation can prevent the concrete from flowing out from the filling hole by the blocking mechanism 28, it can be performed while applying pressure to the concrete in the concrete piston chamber 23, and the workability at the time of tunnel lining is improved. There is no loss.

In the above embodiment, the tail part of the shield machine 10 is doubled, a plurality of concrete piston chambers 23 are provided therein, and an extruding piston is inserted into the concrete piston chamber 23.
24, and press this extrusion piston 24 into a pressure holding jack.
25, the pressure in each concrete piston chamber 23 is adjusted, so that the concrete pressure in each chamber is managed in response to changes in ground pressure (normally, the higher the depth, the higher the pressure). It can be carried out individually and it is possible to reliably and easily maintain the concrete pressure always higher than the ground pressure.

Further, in the embodiment, a concrete piston chamber 23 is provided in the tail portion of the shield machine, and in a factory,
Since the extruding piston 24 is slidably disposed in the concrete piston chamber 23 in a sealed state, the accuracy of the sealing portion of the extruding piston 24 can be maintained at the same level as the seal of a movable portion such as a cutter of a shield machine. Almost all the ground that can be used by shield machines can be handled.

Further, in the embodiment, since the exchange of the seal important for maintaining the pressure of the concrete can be performed safely and easily, it is possible to always maintain the concrete pressure by exchanging the seal even during long excavation. There is an advantage that it is.

Further, in the embodiment, the extruding piston 24 is moved forward along with the supply of the concrete, and when extruding the concrete, the extruding piston 24 is moved to the rear of the shield machine 10. Pressure can be kept almost constant even when supplying concrete, as a result, without applying excessive pressure to the ground and formwork, without pushing up the ground,
In addition, there is an effect that it is not necessary to make the formwork more rigid than necessary.

According to the above, in the embodiment, the pressure in the concrete piston chamber 23 can always be kept higher than the earth pressure and water pressure of the ground, so that there is no water leakage and high-strength high-quality concrete is poured. Is possible.
In addition, since the tail void can be reliably filled, there is an advantage that there is no possibility of land subsidence.

Further, in an embodiment, the extrusion piston 24 always
Since it is configured to press concrete, it is possible to use concrete having a long hardening time, and there is also an effect that cleaning of piping and the like for each ring becomes unnecessary.

“Effects of the Invention” As described above, according to the present invention, the following excellent effects can be obtained.

(1) The method for lining a shield tunnel according to claim 1 is as follows.
While excavating the ground with a cutter device or the like at the tip of the shield machine, the peripheral wall of the excavated tunnel is covered with a form at a predetermined interval, and a lining material is supplied between the form and the peripheral wall. A method for lining a shield tunnel in which an inner surface is lining, wherein a tail portion of a skin plate of a shield machine is formed as a double with an outer tube and an inner tube, and the inner tube and the outer tube of the tail portion are formed inside. A plurality of concrete piston chambers for accommodating the extrusion piston are provided by forming a plurality of partition walls extending in the radial direction of the skin plate between the cylinder and the cylinder. Since it is characterized by supplying the lining material between the formwork and the peripheral wall while pressing so as to be higher than the earth pressure of the mountain, water pressure, there is no water leakage, Excellent effects such as high-quality pouring the lining material strength can be achieved.

Further, according to the above, there is an effect that the construction of the shield tunnel can be performed quickly and safely.

(2) The method for lining a shield tunnel according to claim 2 is as follows.
In the shield tunnel lining method, when the supply pressure of the lining material becomes larger than the set holding pressure of the pressure holding jack, the supply pressure of the lining material causes the extrusion piston to move to the front of the shield machine. Since it is a feature, the same effect as above can be obtained,
In addition, the pressure of the lining material in the concrete piston chamber can be kept almost constant even when the lining material is supplied, and the ground can be pushed up without applying excessive pressure to the ground and formwork. There is also an effect that there is no need to make the formwork more rigid than necessary.

[Brief description of the drawings]

The drawings show an embodiment of the method for lining a shield tunnel of the present invention. FIG. 1 is a side sectional view of a tunnel showing a state in which a shield machine is excavating the ground, and FIG. Figure
FIG. 3 is a sectional view taken along the line II-II, and FIG. 3 is a side view showing a main part of the push-out piston. T ... tunnel, 1 ... form, 10 ... shield machine, 11 ...
... Skin plate, 12 ... Cutter device, 13 ... Propulsion jack, 20 ... Outer cylinder, 21 ... Inner cylinder, 22 ... Partition wall, 23 ...
Concrete piston chamber, 24 ... Extruded piston, 25 ...
... pressure holding jack.

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Toru Kawai 2-16-1 Kyobashi, Chuo-ku, Tokyo Shimizu Construction Co., Ltd. (56) References JP-A-2-217599 (JP, A) JP-A-2 −128093 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) E21D 11/10 E21D 9/06 301

Claims (2)

(57) [Claims] An excavation machine is used to cover a peripheral wall of a tunnel excavated while excavating a ground by a cutter device or the like at a tip end of a shield machine with a predetermined interval, and a lining material is provided between the mold and the peripheral wall. And a lining of the shield tunnel in which the inner surface of the tunnel is wrapped, wherein the tail portion of the skin plate of the shield machine is formed by an outer cylinder and an inner cylinder, and the tail portion is formed. A plurality of concrete piston chambers are formed between the outer cylinder and the inner cylinder to extend in the radial direction of the skin plate, and a plurality of concrete piston chambers for accommodating the extrusion piston are provided. A shield tunnel characterized by supplying a lining material between a formwork and a peripheral wall while pressing the material pressure so as to be higher than the earth pressure and water pressure of the ground. Lining method. 2. The method according to claim 1, wherein when the supply pressure of the lining material is larger than a set holding pressure of the pressure holding jack, the pushing piston is moved by the supply pressure of the lining material. A method for lining a shield tunnel, comprising moving the shield tunnel forward.