JPH0794798B2 - Cast-in-place lining method and shield machine - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cast-in-place lining method and an apparatus used for carrying out the method.

[0002]

2. Description of the Related Art A cast-in-place lining method has been developed which uses a shield machine and directly places concrete without using existing segments. In such a cast-in-place lining method, the following method is adopted in order to improve water blocking performance. <B> Build a concrete lining once. Then attach a tarpaulin to the inside of this primary lining. Then, a method of placing secondary concrete inside the waterproof sheet. <B> A method of placing a water blocking sheet inside the tail plate of the shield machine and placing concrete inside the sheet.

[0003]

[Problems to be Solved by the Invention] The conventional water stopping method described above has the following problems. <a> In the former method, it is always necessary to place concrete for secondary lining. Such a process is a heavy burden in terms of construction period and cost. Furthermore, since the thickness of the cross section becomes thicker by the amount of the lining, it is uneconomical to increase the overall outer diameter. <B> In the latter method, the water blocking sheet between the tail plate and the concrete may be torn when the shield machine advances.

[0004]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and does not require casting of concrete for the secondary lining, and the water proof sheet is not liable to be damaged. The purpose is to provide a construction method.

[0005]

[Means for Solving the Problems] That is, according to the present invention, the inner formwork is assembled inside the tail plate of the shield machine, the lining concrete is placed and pressed, and the shield machine machine reacts to the inner formwork with a reaction force. In the construction method of advancing and taking out, the inner side of the tail plate is provided with a reinforcing ring concentric with the inner formwork at a fixed interval, and this reinforcing ring is configured to allow expansion and contraction of the inner diameter. It is a cast-in-place lining method in which concrete is placed while reinforcing the waterproof sheet directly or indirectly from the outside. Further, the present invention assembles an inner formwork inside a tail plate of a shield machine, places a lining concrete and pressurizes it, and the shield machine uses a shield which is used in a method of advancing by applying a reaction force to the inner formwork. In the excavator, a reinforcing ring that is concentric with the inner mold is provided inside the tail plate with a certain distance from the inner mold, and the reinforcing ring is configured as an inner and outer double cylinder body.
This is a shield machine, in which the inner cylinder is divided into a plurality of parts, and the double cylinder is provided with slopes that are in contact with each other so that the inner diameter can be expanded and contracted by relative movement between the slopes.

[0006]

The present invention will be described below with reference to the drawings. <a> Inner formwork system The shield machine of the present invention uses an inner formwork 1 and a water blocking sheet corresponding to an outer formwork, and a concrete 3 between them.
It is a method of constructing a lining by placing. That is, the inner formwork 1 and the water stop sheet concentric with the inner formwork 1 are provided inside the tail plate 3, concrete 6 is placed between them, and the concrete 6 is pressed by the press jack 4 to perform dewatering. It is a method to let. The forward movement of the shield machine is performed by applying a reaction force to the inner formwork 1 and extending the propulsion jack 5.

<B> Characteristics of Water-Proof Sheet and Water-Proof Frame Although the above construction is basically known, in the conventional apparatus, the outer die is made of a strong thick steel plate to form an outer die. I am doing it. This is because when the concrete 6 is pressed by the press jack 4, the pressure is also transmitted to the outer form. For this reason, the outer formwork had to have a strong structure and to withstand the pressure and compaction pressure of concrete and not deform. On the other hand, in the apparatus of the present invention, the member corresponding to the outer mold is a water blocking sheet 21 having no rigidity at all, or a water blocking sheet attached to the inner surface of the water blocking frame 2 of a thin plate body having low rigidity. adopt.

<C> Reinforcing Ring A concentric reinforcing ring is arranged on the outer circumference of the waterproof sheet 21 having no rigidity or the waterproof frame 2 formed of a thin plate. The reinforcing ring holds the shapes of the water blocking sheet 21 and the water blocking frame 2 and acts on the water blocking sheet 21 and the water blocking frame 2 (hereinafter, represented by the water blocking frame 2 as a representative) by pressurized concrete. It is an external reinforcing member for receiving the pressure to be applied. Since it is a reinforcing ring, when concrete is pressed by the press jack, it must be superposed on the outer periphery of the water blocking frame 2 to receive a force. For that purpose, the inner diameter of the reinforcing ring may be made to coincide with the outer diameter of the water blocking frame 2, but this cannot advance the reinforcing ring as the shield machine advances. Therefore, the reinforcing ring needs to be able to expand and contract its inner diameter. Due to this expansion and contraction, the reinforcing ring is constituted by inner and outer double rings. That is, the inner reinforcing ring 7
And the outer reinforcing ring 8.

<D> Inner Reinforcement Ring The inner reinforcement ring 7 is a cylindrical body divided into a plurality of pieces. On the outer side thereof, a plurality of stages of annular slopes 71 are formed like bamboo shoots.
The annular slope 71 has a repetitive shape in which the diameter gradually increases toward the hole mouth side, returns to the original diameter at a certain position, and gradually increases again toward the hole mouth side. A jack is arranged on the face side of the inner reinforcing ring 7 to enable the compulsory back-and-forth movement of each divided inner reinforcing ring 7. When the diameter of the inner reinforcing ring 7 is shrunk to the minimum, it becomes almost the same as the outer diameter of the water blocking frame 2.

<E> Outer Reinforcement Ring An outer reinforcement ring 8 is installed outside the inner reinforcement ring 7 and inside the tail plate 3. A jack is also arranged on the face of the outer reinforcing ring 8 to allow forcible back and forth movement. On the inner side of the outer reinforcing ring 8, a plurality of stages of annular slopes 81 are formed like bamboo shoots. The annular inclined surface 81 has a repetitive shape in which the diameter once expanded gradually decreases toward the mouth opening side, expands again at a certain position, and gradually decreases again toward the hole opening side. The annular slope 81 of the outer reinforcing ring 8 is in contact with the annular slope 71 of the inner reinforcing ring 7. Since the tail plate 3 exists outside the outer reinforcing ring 8, the diameter thereof does not change. Therefore, the relative movement of the inner and outer reinforcing rings 7 and 8 causes the diameter of the inner reinforcing ring 7 to expand and contract. Naturally, the same effect can be obtained even if the inclination directions of the slopes are completely opposite.

[0011]

[Operation] Next, the operation will be described. <A> Placing concrete The diameter of the inner reinforcing ring 7 is reduced to the minimum by moving the inner reinforcing ring 7 and the outer reinforcing ring 8. The water blocking sheet 21 is attached to the inner surface of the inner reinforcing ring 7 either directly or through the water blocking frame 2. Further, the inner formwork 1 is assembled, and concrete 6 is press-fitted between the inner formwork 1 and the water blocking frame 2.

<B> Pressurization of concrete The concrete 6 that has been press-fitted has its entire circumference surrounded by a water-stop sheet 21.
It is surrounded by. The concrete 6 is pressed by the press jack 4. Water-proof sheet 2 due to the pressure
1 or the water blocking frame 2 is spread outward, but the inner and outer reinforcing rings 7 and 8 are integrally positioned outside the water blocking sheet 2, so that the water blocking sheet 21 is a member having no rigidity. Or, even if the water blocking frame 2 is made of a thin steel plate, it is not deformed because it is entirely reinforced.

<C> Advance of shield machine The shield machine is advanced when the concrete is hardened. At that time, if the inner reinforcing ring 7 is in contact with the water blocking sheet 21 and the water blocking frame 2 integrally, the inner reinforcing ring 7 cannot move forward. Therefore, the inner and outer reinforcing rings 7 and 8 are slid to allow the inner reinforcing rings to expand. If the edges of the water blocking sheet and the water blocking frame 2 are cut off in this way, friction does not occur, so that the shield machine can be advanced by the extension of the propulsion jack. Even when the shield machine is moved, the waterproof sheet is not damaged because it does not contact the structure that moves directly.

<D> Injection of mortar Mortar or the like is injected to the outside of the water blocking frame 2 to fill the space between the ground and the ground to prevent subsidence.

[0015]

Since the present invention is as described above, the following effects can be obtained. <a> The lining concrete is surrounded by a waterproof sheet around the entire circumference. Therefore, the water-stopping property of the concrete is perfect, and it is not necessary to perform double lining as in the conventional case, and the water-stopping can be completed only by the primary lining. And the reinforcement ring on the outer periphery of the water blocking sheet or water blocking frame
The shield machine does not come into contact with the waterproof sheet when moving. Therefore, there is no risk that the waterproof sheet will be damaged even when the shield machine advances. <B> The waterproof sheet corresponding to the outer formwork of the lining concrete is surrounded by the reinforcing ring around the outer circumference with or without the waterproof frame. Therefore, a waterproof sheet having no rigidity can be used, and the waterproof frame can be made of a thin plate, which is extremely economical. <C> Even soft, flooded ground can be easily constructed. <D> A clearance can be provided between the tail plate and the reinforcing ring. Therefore, it is possible to easily pass a curve having a small radius. <E> Since there is a formwork on both the inside and outside, and concrete is injected between them, the amount of concrete placed is smaller than the method that directly targets the ground without using the outside formwork. It is always constant and stable construction can be performed.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a main part of a shield machine used in a construction method of the present invention.

[Figure 2] Its enlarged view

Claims (3)

[Claims] 1. An inner formwork is assembled inside a tail plate of a shield machine, and lining concrete is placed and pressed,
In the shield excavator, which is a method of advancing by applying a reaction force to the inner formwork, a reinforcing ring that is concentric with the inner formwork is provided inside the tail plate with a certain distance from the inner formwork. A waterproof sheet is attached to this, and this reinforcing ring is configured to allow expansion and contraction of the inner diameter, and the concrete is placed while reinforcing the waterproof sheet from the outside with the reinforcing ring. 2. The cast-in-place lining method according to claim 1, wherein a water blocking frame concentric with the inner form is interposed between the water blocking sheet and the reinforcing ring. 3. An inner formwork is assembled inside a tail plate of a shield machine, and lining concrete is placed and pressed,
The shield machine is a shield machine used in the method of advancing by taking a reaction force to the inner formwork.Inside the tail plate, a reinforcing ring that is concentric with the inner formwork is provided at a fixed distance from the inner formwork. , The reinforcing ring is configured as an inner and outer double cylinder, the inner cylinder is divided into a plurality of parts, and the double cylinder is provided with slopes that contact each other. Shield machine with the ability to expand and contract