JP2002147165A - Shield excavator and shield excavation method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a shield excavator capable of corresponding to a work involving a curve with a steep angle of bend by increasing the overall length. SOLUTION: A tail portion of a skin plate 23 constituting an outer shell of this shield excavator is constituted by an assembly of an outer cylindrical body 23B and an inner cylindrical body 23A made expandable by the coaxial arrangement and freely slidability relative to the axis direction; when recessed portions 25A and 25B and projected portions 24A and 24B formed on the peripheral surface facing each other of the outer cylindrical body 23B and the inner cylindrical body 23A are fitted together, the outer cylindrical body 23B and the inner cylindrical body 23A are combined together in a lapped state in the thickness direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shield excavator and a shield excavation method.

[0002]

2. Description of the Related Art FIG. 4 shows a schematic configuration of a general conventional shield excavator. This shield excavator 10 is provided with a front body 2 provided with a cutter 1 for excavating the ground at a front portion of a skin plate 3 constituting an outer shell thereof so as to swing. Inside, a mechanism for sending the excavated earth and sand backward, an erector for assembling the segment 7 into a predetermined shape, and a propulsion jack 4 for propelling the shield excavator 10 by obtaining a reaction force from the assembled segment.
Etc. are provided.

In this shield excavator 10, the tail portion of the skin plate 3 is set to be long so that a segment 7 for two rings, which is one ring larger than that of a normal shield excavator, can be assembled. Thereby, it is possible to contribute to high-speed construction.

[0004]

However, the shield excavator 10 having such a long overall length has a problem that it is difficult to construct a sharp curve.

An object of the present invention is to provide a shielded excavator capable of coping with a sharp curve construction and capable of increasing the overall length in consideration of the above circumstances.

[0006]

According to a first aspect of the present invention, there is provided a shield excavator in which at least a part of a length of a skin plate constituting an outer shell of the shield excavator is coaxially arranged and extends in an axial direction. It is composed of a combination of two cylinders that can be extended and contracted by being made relatively slidable,
The two cylinders are combined in a state of being wrapped with each other in the thickness direction.

According to a second aspect of the present invention, there is provided the shield excavator according to the first aspect, wherein the two cylinders have a double structure of an outer cylinder and an inner cylinder disposed on the inner periphery of the outer cylinder. The outer cylinder and the inner cylinder are wrapped in the thickness direction by combining the recesses and the projections formed on the opposing peripheral surfaces of the outer cylinder and the inner cylinder. And

According to a third aspect of the present invention, there is provided the shield excavator according to the first aspect, wherein one of the two cylinders is:
A porous body comprising a collection of a large number of rods arranged in a cylindrical shape with their axes aligned, and the other cylindrical body having a large number of holes within the thickness of the peripheral wall into which the rods are slidably inserted in the axial direction. It is characterized by comprising a cylindrical body.

A fourth aspect of the present invention is the shield excavator according to the third aspect, wherein a hydraulic jack for extending and retracting the rod is formed by filling hydraulic oil into the hole of the porous cylindrical body. And

According to a fifth aspect of the present invention, there is provided a shield excavating method according to any one of the first to fourth aspects, wherein when excavating a tunnel with the shield excavator according to any one of the first to fourth aspects, the excavation is performed in a straight section by exposing two cylindrical bodies in an extended state. The excavation is performed on the curved portion with the two cylinders in the retracted state.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic cross-sectional side view showing the entire configuration of a shield excavator common to each embodiment. This shield excavator 20 is provided with a front trunk portion 2 provided with a cutter 1 for excavating the ground in a front part of a skin plate 3 constituting an outer shell of the shield excavator 20 so as to be swingable. Various mechanisms such as a mechanism for sending the excavated earth and sand backward, an erector for assembling the segment 7 into a predetermined shape, and a propulsion jack 4 for propelling the shield excavator 20 by obtaining a reaction force from the assembled segment are provided. The tail part of the skin plate 3 is fixed to the fixed cylinder 3A and the movable cylinder 3
B is configured.

The movable cylinder 3B is arranged coaxially with the fixed cylinder 3A and is slidably combined in the axial direction. By sliding the movable cylinder 3B in the direction of the arrow, the tail of the skin plate 3 is adjusted. The length of the part can be adjusted.

That is, as shown in FIG. 1 (a), if the movable cylinder 3B is extended rearward, the total length of the shield excavator 20 can be increased to L1, and as shown in FIG. 1 (b). As described above, if the movable cylinder 3B is retracted, the shield excavator 20
Can be shortened to L2. In this case, the length of expansion and contraction of the movable cylinder 3B is set according to the width (length in the axial direction) of the segment 7, and the like.
When the length of the tail part is increased, it corresponds to the segment 7 of two rings, and when the length of the tail part is shortened, it corresponds to the segment 7 of one ring.

When the tail portion of the skin plate 3 is constituted by the combination of the fixed cylinder 3A and the movable cylinder 3B as described above, if these are simply constituted by a double structure of an inner cylinder and an outer cylinder, The thickness of the tail part becomes large. Therefore, in the present invention, the fixed tubular body 3A and the movable tubular body 3B are combined in a state of being wrapped in the thickness direction. A specific example of the structure will be described below.

In the structure of the first embodiment shown in FIG. 2, the tail portion of the skin plate 23 is made up of an inner cylindrical body 23A as a fixed cylindrical body and an outer cylindrical body 23B as a movable cylindrical body arranged on the outer periphery thereof. It consists of a combination. And the inner cylinder 2
The inner cylindrical body 23A and the outer cylindrical body 23B are wrapped in the thickness direction by fitting the corrugated concave parts 25A, 25B formed on the opposing peripheral surfaces of the 3A and the outer cylindrical body 23B with the convex parts 24A, 24B. While maintaining the strength of each of the cylinders 23A and 23B (the axial strength of each of the cylinders 23A and 23B is increased due to the corrugated unevenness of the cross section), the entirety of the skin plate 23 as a tail portion is increased. The thickness is kept small.

In the shield excavator having such a tail structure, as described above, the entire length of the shield excavator can be increased by sliding the outer cylinder 23B to the rear side. The overall length of the shield excavator can be shortened by sliding the excavator forward. Therefore, in the case of ordinary straight construction, the total length is set to be long and 2
Excavation is performed at the tail part of the ring, and when making a sharp curve, the total length is set short and excavation is performed at the tail part of one ring.
By doing so, it becomes possible to cope with sharp curve construction while supporting high-speed construction. In addition, since the width of the segment 7 is small in the sharp curve portion, even if the tail portion is shortened, the function as the shield excavator is not impaired at all.

Although a mechanism for sliding the outer cylinder 23B is not shown here, the outer cylinder 23B is not shown.
The slide B may be performed by a dedicated driving mechanism, may be performed by using a propulsion jack, or may be manually performed by using a chain block, a winch, or the like.

FIGS. 3A and 3B show the structure of the tail portion of the skin plate 33 according to the second embodiment. In this structure, the movable cylinder 33B constituting the skin plate 33
Is constituted by an aggregate of a large number of rods 32 arranged in a cylinder with their axes aligned, and the fixed cylindrical body 33A is formed by a cylindrical aggregate of pipes 31 into which the rods 32 are slidably inserted in the axial direction. Make up. The rod 32 has a connecting ring 3 at the tip.
The pipes 31 are connected in an annular shape, and the entire pipe 31 is integrally connected. Instead of the aggregate of the pipes 31, a porous cylindrical body (hollow cylindrical body) having a large number of insertion holes for the rod 32 within the thickness of the peripheral wall may be used. Further, the rod 32 may be solid or hollow.

In such a structure, since each rod 32 is slidably inserted into the pipe 31, the movable cylindrical body 33 B composed of the aggregate of the rods 32 is a fixed cylindrical body composed of the aggregate of the pipes 31. It is slidable in the axial direction with respect to 33A. Therefore, the first
The same usage as the embodiment can be performed. Moreover, in the case of this structure, the thickness of the tail portion of the skin plate 33 is
Since it is determined by the diameter of 1, the thickness of the tail portion can be suppressed. Also, since the relationship between the pipe 31 and the rod 32 is the same as the relationship between the hydraulic cylinders, the working oil is sealed in the pipe 31 so that the pipe 31 and the rod 32
A hydraulic jack that drives the rod 32 to expand and contract can also be configured. By doing so, the sliding operation of the movable tubular body 33B can be performed using its own function as a hydraulic jack.

In the first embodiment, the inner cylinder 23
Although A is positioned forward and outer cylinder 23B is positioned rearward, it may be positioned oppositely. In the second embodiment,
The fixed cylindrical body 33A is composed of an aggregate of the pipes 31 and the movable cylindrical body 33B is composed of an aggregate of the rods 32, but may be reversed. That is, the fixed cylindrical body 33A may be configured by an aggregate of the rods 32, and the movable cylindrical body 33B may be configured by an aggregate of the pipes 31.

In the above embodiment, the combination structure of the two cylinders (the inner cylinder 23A, the outer cylinder 23B, the fixed cylinder 33A, and the movable cylinder 33B) is arranged at the tail of the skin plate. It may be extended to the front side,
The entire length of the skin plate may be constituted by a combination of two cylinders.

The shape of the shield excavator is not limited at all, and may be any shape such as a circular shape in cross section or a rectangular shape in cross section, for example, in accordance with the cross sectional shape of the tunnel to be constructed. In the above-mentioned shield excavator, a combination of two cylinders is used, but a combination of three or more cylinders may be used.

[0023]

As described above, according to the first aspect of the present invention, at least a part of the skin plate in the longitudinal direction is formed by a combination of two relatively slidable cylinders. The total length of the shield excavator can be adjusted according to the construction situation. Therefore, at the time of straight line construction, high-speed construction is possible by setting the total length to be long, and at the time of sharp curve construction, it is possible to cope by shortening the total length. Further, since the two cylinders are combined in a state of being wrapped with each other in the thickness direction, the thickness of the portion can be suppressed without lowering the strength of the cylinder as much as possible.

According to the second aspect of the present invention, the two cylindrical bodies are constituted by the outer cylindrical body and the inner cylindrical body, and the outer cylindrical body and the inner cylindrical body are fitted with the concave portion and the convex portion on the peripheral surface to thereby form the outer cylindrical body. Since the cylindrical body and the inner cylindrical body are wrapped in the thickness direction, the overall thickness can be suppressed while maintaining the strength of the cylindrical body.

According to the third aspect of the present invention, since the two cylinders are composed of an aggregate of the porous cylinder and the rod, the entire thickness can be kept within the range of the thickness of the porous cylinder. , The thickness can be reduced.

According to the fourth aspect of the present invention, a hydraulic jack for extending and retracting the rod is formed by filling the working oil into the hole of the porous cylindrical body, so that another drive source for sliding is provided. There is no need, and the configuration can be simplified.

According to the fifth aspect of the present invention, when excavating a tunnel with a shield excavator, the excavation is performed with the two cylinders extended in the straight section, and the two cylinders are retracted in the sharp curve section. Since the excavation is performed at high speed, it is possible to cope with sharp curve construction while achieving high-speed construction.

[Brief description of the drawings]

FIG. 1 is a schematic side sectional view showing the entire configuration of a shield excavator according to the present invention, in which (a) is a view in which the entire length of the shield excavator is extended, and (b) is a state in which the overall length is shortened. FIG.

FIG. 2 is an enlarged view of a main part showing a relationship between a fixed tubular body and a movable tubular body of the shield excavator according to the embodiment of the present invention.

FIG. 3A is an enlarged view of a main part showing a relationship between a fixed cylinder and a movable cylinder of a shield excavator according to another embodiment of the present invention;
(B) is a cross-sectional view thereof.

FIG. 4 is a schematic side sectional view showing an example of a conventional shield excavator.

[Explanation of symbols]

 Reference Signs List 3 skin plate 3A fixed cylinder 3B movable cylinder 20 shield excavator 23 skin plate 23A inner cylinder 23B outer cylinder 24A projection 24B projection 25A recess 25B recess 31 pipe 32 rod 33 skin plate 33A fixed cylinder 33B movable cylinder body

Claims (5)

[Claims] At least a part of a length of a skin plate constituting an outer shell of a shield excavator is coaxially arranged and is relatively slidable in an axial direction so as to be extensible. A shield excavator comprising a combination of cylindrical bodies, wherein the two cylindrical bodies are combined in a state of being wrapped with each other in a thickness direction. 2. The two cylinders are combined as a double structure of an outer cylinder and an inner cylinder disposed on the inner periphery of the outer cylinder, and the outer cylinder and the inner cylinder are opposed to each other. The shield excavator according to claim 1, wherein the outer cylinder and the inner cylinder are wrapped in the thickness direction by fitting the concave portion and the convex portion formed on the peripheral surface. 3. One of the two cylinders is:
A porous body comprising a collection of a large number of rods arranged in a cylindrical shape with their axes aligned, and the other cylindrical body having a large number of holes within the thickness of the peripheral wall into which the rods are slidably inserted in the axial direction. The shield excavator according to claim 1, comprising a cylindrical body. 4. The shield excavator according to claim 3, wherein a hydraulic jack for extending and retracting the rod is configured by sealing hydraulic oil into a hole of the porous cylindrical body. 5. Excavation of a tunnel with a shield excavator according to any one of claims 1 to 4, in which two cylinders are extended in a straight portion, and two cylinders are retracted in a sharp curve portion. A shield excavation method characterized by excavating in a state.