JPH04327697A - Method of cast-in-place lining construction and shield excavator - Google Patents

Abstract

PURPOSE:To obtain the method of cast-in-place lining construction having excellent cut-off properties and a shield propeller. CONSTITUTION:In the method of construction, in which inner forms 1 are assembled inside the table plate of a shield excavator, lining concrete is placed and pressed and a shield excavator is propelled by applying reaction to the inner forms, reinforcing rings 7, 8 concentric to the inner forms 1 are installed. The reinforcing rings are constituted so that inside diameters thereof can be expanded and contracted, and lining is conducted by placing concrete while a cut-off sheet 21 and a cut-off frame 2 are reinforced from the outside by the reinforcing rings. The concentric reinforcing rings 7, 8 are organized as internal and external double cylindrical bodies at that time, and the inside diameters can be expanded and contracted by relative displacement between slant faces.

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 to carry out the method.

0002

BACKGROUND OF THE INVENTION A cast-in-place lining method has been developed that utilizes a shield excavator and directly places concrete without using existing segments. The following methods are used to improve water-stopping properties in these cast-in-place lining construction methods. <B> Construct the concrete lining once. A waterproof sheet is then attached to the inside of this primary lining. Then, a method of pouring secondary concrete inside the water stop sheet. <B> A method in which a water stop sheet is attached to the inside of the tail plate of the shield excavator, and concrete is poured inside it.

0003

[Problems to be Solved by the Invention] The conventional water stopping method described above has the following problems. <B> In the former method, it is always necessary to pour concrete for the secondary lining. Such a process poses a large burden both in terms of construction time and costs. Furthermore, since the cross-sectional thickness is increased by the lining, the overall outer diameter must be increased, which is uneconomical. <B> In the latter method, there is a risk that the water stop sheet between the tail plate and the concrete may be torn when the shield tunneling machine moves forward.

0004

[Object of the present invention] The present invention has been made in order to improve the above-mentioned problems. The purpose is to provide construction methods.

[0005]

[Means for solving the problem] That is, the present invention assembles an inner formwork inside the tail plate of a shield excavator, places lining concrete and pressurizes it, and the shield excavator applies a reaction force to the inner formwork. In this construction method, a reinforcing ring is provided inside the tail plate and is concentric with the inner formwork at a certain distance from the inner formwork. This is a cast-in-place lining construction method in which concrete is poured while directly or indirectly reinforcing the water-stop sheet from the outside. Moreover, the present invention
The shield excavator uses a construction method in which the inner form is assembled inside the tail plate of the shield excavator, lining concrete is placed and pressurized, and the shield excavator moves forward by taking a reaction force to the inner form. A reinforcing ring concentric with the inner formwork is provided on the inside of the plate at a certain interval from the inner formwork, and the reinforcing ring is configured as a double inner and outer cylinder, and the inner cylinder is divided into multiple parts. Furthermore, the double cylindrical body is provided with slopes that contact each other, and the shield tunneling machine is constructed so that the inner diameter can be expanded and contracted by relative movement between the slopes.

[0006]

[Structure of the present invention] The present invention will be explained below with reference to the drawings. <A> Inner formwork method The shield excavator of the present invention uses an inner formwork 1 and a water-stop sheet corresponding to the outer formwork, and concrete 3 is placed between them.
This is a method of constructing a lining by pouring concrete. That is, an inner formwork 1 and a water-stop sheet concentric with the inner formwork 1 are provided inside the tail plate 3, concrete 6 is poured between the two, and this concrete 6 is pressurized by a press jack 4 to dewater. This is a method that allows The shield tunneling machine moves forward by taking a reaction force to the inner formwork 1 and extending the propulsion jack 5.

<B> Features of water-stop sheet and water-stop frame The above configuration is basically known, but in conventional equipment, the outer formwork is constructed from a strong thick steel plate and is configured as an outer formwork. It has been done. This is because when the concrete 6 is pressurized by the press jack 4, that pressure is also transmitted to the outer formwork. For this reason, the outer formwork had to have a strong structure that could withstand the pressure of concrete and compaction without deforming. In contrast, in the device of the present invention, the member corresponding to the outer formwork is either a water-stop sheet 21 with no rigidity, or a water-stop sheet pasted on the inner surface of the water-stop frame 2, which is a thin plate with low rigidity. adopt.

<C> Reinforcing ring A concentric reinforcing ring is arranged around the outer periphery of the water-stop sheet 21, which has no rigidity, or the water-stop frame 2, which is made of a thin plate. This reinforcing ring maintains the shapes of the water stop sheet 21 and the water stop frame 2, and acts on the water stop sheet 21 and the water stop frame 2 (hereinafter described as the water stop frame 2) by pressurized concrete. This is an external reinforcing member for receiving pressure. Since this is a reinforcing ring, when the concrete is pressurized by a press jack, it must be placed exactly on the outer periphery of the water stop frame 2 to receive the force. For this purpose, it is sufficient to make the inner diameter of the reinforcing ring match the outer diameter of the water stop frame 2, but in this case, the reinforcing ring cannot be moved forward as the shield tunneling machine moves forward. For this purpose, the reinforcing ring must be able to expand and contract its inner diameter. For this expansion and contraction, the reinforcing ring is composed of double inner and outer rings. In other words, the inner reinforcing ring 7
and an outer reinforcing ring 8.

<D> Inner reinforcing ring The inner reinforcing ring 7 is a cylindrical body divided into a plurality of parts. A plurality of bamboo-shaped annular slopes 71 are formed on the outside thereof. This annular slope 71 has a repeating shape in which the diameter gradually increases toward the hole side, returns to the original diameter at a certain position, and gradually increases in diameter again toward the hole side. A jack is placed on the face side of the inner reinforcing ring 7,
Forcibly moving each divided inner reinforcing ring 7 back and forth is possible. When the diameter of this inner reinforcing ring 7 is contracted to the minimum, it becomes approximately the same as the outer diameter of the water stop frame 2.

<E> Outer reinforcing ring An outer reinforcing ring 8 is installed outside the inner reinforcing ring 7 and inside the tail plate 3. A jack is also arranged on the face side of this outer reinforcing ring 8 to enable forcible back and forth movement. On the inside of the outer reinforcing ring 8, a plurality of annular slopes 81 are formed in the shape of a bamboo shoot. The annular slope 81 has a repeating shape in which the diameter increases once, gradually decreases toward the hole side, expands again at a certain position, and gradually decreases in diameter again toward the hole 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, its diameter does not change. Therefore, the diameter of the inner reinforcing ring 7 is expanded or reduced by the relative movement of the inner and outer reinforcing rings 7, 8. It goes without saying that the same effect can be obtained even if the directions of inclination of the slopes are completely opposite.

[0011]

[Operation] Next, the operation will be explained. <A> 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 during concrete placement. A water stop sheet 21 is attached to the inner surface of the inner reinforcing ring 7 either directly or via the water stop frame 2. Furthermore, the inner formwork 1 is assembled, and concrete 6 is press-fitted between the inner formwork 1 and the water stop frame 2.

<B> The entire circumference of the concrete 6 that has been pressurized is surrounded by a water-stop sheet 21. This concrete 6 is pressurized by a press jack 4. The water stop sheet 21 or the water stop frame 2 is pushed outward by the pressure, but since the inner and outer reinforcing rings 7 and 8 are integrally located outside, the water stop sheet 21 has a rigid structure. Even if there are no members at all, or even if the water stop frame 2 is made of a thin steel plate, it will not deform because the entire structure is reinforced.

<C> Advancement of the shield excavator Once the concrete has hardened, the shield excavator is advanced. At that time, if the inner reinforcing ring 7 is in integral contact with the water stop sheet 21 and the water stop frame 2, it will not be possible to move forward. Therefore, the inner and outer reinforcing rings 7 and 8
Slide to allow expansion of the inner reinforcing ring. If the edges of the water stop sheet and the water stop frame 2 are cut in this way, no friction will occur, so the shield excavator can be moved forward by extension of the propulsion jack. Even when the shield tunneling machine moves, the water stop sheet does not come into direct contact with the moving structure, so it will not be damaged.

<D> Injecting mortar Mortar or the like is injected into the outside of the water stop frame 2 to fill the gap between it and the ground to prevent it from sinking.

[0015]

[Effects of the Invention] Since the present invention is as explained above, the following effects can be obtained. <A> The concrete lining is surrounded all around by a water-stop sheet. Therefore, the water-stopping properties of concrete are perfect, and there is no need to perform double lining as in the past, and complete water-stopping can be achieved with only the primary lining. And the reinforcing ring around the outer periphery of the water stop sheet or water stop frame is
When the shield tunneling machine is moved, it does not come into contact with the water stop sheet. Therefore, there is no risk of the water stop sheet being damaged by the advance of the shield tunneling machine. <B> The outer periphery of the water-stop sheet, which corresponds to the outer formwork of the lining concrete, is surrounded by a reinforcing ring with or without the water-stop frame. For this purpose, a water stop sheet with no rigidity can be used, and the water stop frame can be constructed from a thin plate, which is extremely economical. <C> It can be easily constructed even on soft, sluggish ground. <N> A clearance can be provided between the tail plate and the reinforcing ring. Therefore, it is possible to easily pass through curves with small radii. <E> Since this method has formwork on both the inside and outside, and concrete is poured between them, the amount of concrete poured is reduced compared to methods that do not use outside formwork and directly target the ground. It is always constant and stable construction can be performed.

[Brief explanation of drawings]

[Fig. 1] Cross-sectional view of main parts of a shield excavator used in the construction method of the present invention

[Figure 2] Enlarged view

Claims (3)

[Claims] Claim 1: Assemble an inner formwork inside the tail plate of a shield excavator, pour concrete lining and pressurize it,
The shield tunneling machine moves forward by taking a reaction force from the inner formwork, and a reinforcing ring is installed inside the tail plate at a certain distance from the inner formwork, and is concentric with the inner formwork. This is a cast-in-place lining construction method in which a water-stop sheet is installed, this reinforcing ring is configured to allow expansion and contraction of the inner diameter, and concrete is poured while the water-stop sheet is reinforced from the outside with the reinforcing ring. 2. The cast-in-place lining method according to claim 1, wherein a water-stop frame concentric with the inner form is interposed between the water-stop sheet and the reinforcing ring. Claim 3: Assemble the inner formwork inside the tail plate of the shield excavator, pour concrete lining and pressurize it,
A shield tunneling machine is a shield tunneling machine used in a construction method that moves forward by taking a reaction force to the inner formwork.A reinforcing ring is installed on the inside of the tail plate at a constant distance from the inner formwork, and is concentric with the inner formwork. , the reinforcing ring is configured as an inner and outer double cylinder, the inner cylinder is divided into multiple parts, and the double cylinders are further provided with slopes that contact each other, and the inner diameter is adjusted by the relative movement between the slopes. A shield excavator configured to allow expansion and contraction of