JPH0649665Y2 - Shield machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention relates to a cast-in-place type shield excavator in which concrete is poured on site to form a lining in parallel with excavation.

<Prior art> Generally, a segment is used for lining a shield tunnel, but a shield machine used for segment tunnel construction has a tail clearance between the inner surface of its tail and the outer surface of the segment. It has a void called.

This tail clearance is used as a space for directional control of the shield machine, as well as a spare space for assembling the segments.

<Problems to be Solved by the Present Invention> As described above, in the case of the segment type shield machine, there is a tail clearance.

On the other hand, in the case of the cast-in-place type shield machine, concrete is placed in close contact with the inner surface of the tail plate, so that there is no tail clearance unlike the segment type.

Therefore, there are the following problems.

<B> If the excavation direction of the shield machine is forcibly corrected, the tail plate will be constrained by the soft lining or hardened lining immediately after driving.

Therefore, in the case of a cast-in-place type shield machine, it is very difficult to control the direction.

<B> For the reasons described above, the adaptability of curved construction is poor, and it is not possible to accommodate sharply curved construction at all.

<C> Further, like the shield machine described in Japanese Utility Model Laid-Open No. 2-33898, an auxiliary tail frame pivotally supported by an auxiliary tail jack installed inside the frame is used in the tail frame of the shield machine. Thus, there is an example of performing the direction control and the curve construction, which are the above-mentioned problems, but the current situation is that it is impossible to completely control the movement of the auxiliary tail frame in all directions.

<Purpose of the Invention> The present invention has been made to solve the above problems, and an object thereof is to provide the following shield machine.

<a> A shield machine with easy direction control.

<B> A shield machine with excellent compatibility with curved construction.

<Structure of the Invention> An embodiment of the invention will be described below.

<a> Shield excavator The shield excavator according to the present invention has a double structure in which an inner cylinder that allows free movement in the tunnel crossing direction is provided inside the tail portion.

The structure of the tail portion of the shield machine will be described with reference to FIGS.

The shield machine 1 includes a shield body 1a and a shield body.
The tail plate 1b is attached to and detached from the la 1a.

Further, the shield machine 1 may have a known direction correcting function.

The tail plate 1b is made of a steel tubular body, and an annular ring girder 2 is fixed to the inside of the tail plate 1b. A cylinder 3 is provided.

Inside the tail plate 1b, a plurality of sets of shield jacks 4 and pressure jacks 5 are attached, penetrating the plate surface of the ring girder 2.

The shield jack 4 is a jack for digging the shield machine 1 by obtaining a reaction force at the end of the inner formwork 6 arranged inside the tail plate 1b, and the pressure jack 5 is the inner formwork 6 Gable plate ring 7 slidably installed between the inner cylinder 3 and
It is a jack for applying a pressing force to concrete through.

Needless to say, publicly known means other than the above can be adopted as the concrete pressurizing means and the shield excavating means.

<B> Inner cylinder The inner cylinder 3 has a smaller diameter than the tail plate 1b, and the ring girder 2
Is a cylindrical body having the entire length from the attachment position of to the peripheral end of the tail plate 1b.

The present invention utilizes an annular space formed between the tail plate 1b and the inner cylinder 3 as a tail clearance.

That is, as shown in FIG. 2, the closing member 8 is attached between the rear portion 3a of the inner cylinder 3 and the rear end of the tail plate 1b to close the same.

The closing body 8 is formed of a material having flexibility or elasticity capable of following the change in the gap between the inner cylinder 3 and the tail plate 1b.

The other end of the inner cylinder 3 is attached to the ring girder 2 while allowing movement in the transverse direction of the tunnel.

That is, both ends of the inner cylinder 3 are independently mounted so as to be movable in the transverse direction of the tunnel.

<C> Elastic support means for inner cylinder The shield machine according to the present invention elastically supports the inner cylinder 3 inside the tail plate 1b.

In this embodiment, as a means for elastically supporting the inner cylinder 3,
A pressure bag 9 is placed in the annular space between the tail plate 1b and the inner cylinder 3.
The case of housing a room will be described.

The pressure-resistant bag 9 is composed of a bag made of a material capable of preventing leakage of fluid and a fluid material having fluidity to be enclosed in the bag.

For the bag, is one bag that can cover the entire area of the annular space formed between the tail plate 1b and the inner cylinder 3 (3rd
(See FIG. 4), or a plurality of bags having continuity may be connected along the circumferential or axial direction of the tunnel (FIG. 4).

Further, as the fluid material sealed in the bag, for example, air, water, oils, or a resin having a non-solidifying property can be used.

Further, the pressure-proof bag 9 is constructed so that the internal pressure can be adjusted.

<Operation> Next, a tunnel construction method will be described.

<a> Construction of straight line section When the shield machine 1 travels straight, the reinforcing bar 10 is placed between the inner cylinder 3 and the ground of the tunnel, and concrete is placed in the formwork space shielded by the end plate ring 7. While constructing the straight part of the tunnel.

<B> Construction of curved section The shield machine 1 has a substantial tail clearance between the tail plate 1b of the tail section and the inner cylinder 3.

Therefore, only the tail plate 1b moves in the correction direction while the inner cylinder 3 remains stationary.

That is, the pressure-proof bag 9 on the correction moving side of the tail plate 1b becomes thin, and conversely, the pressure-proof bag 9 on the other end side in the correction direction becomes thicker,
Allows movement of the tail plate 1b.

Therefore, unlike the conventional case, the phenomenon of the tail plate 1b biting into concrete does not occur.

Further, the pressure inside the pressure-resistant bag 9 is adjusted in consideration of the degree of the curve and other conditions.

<Other Embodiments> Other means for elastically supporting the inner cylinder 3 will be used.
A method of interposing a plurality of coil springs or leaf springs between the tail plate 1b and the tail plate 1b may be adopted.

Further, it is needless to say that the invention can be applied to a known shield excavator of a type in which two cylinders are connected to the front and rear of the shield body 1a so that the shield body 1a can be bent in the middle.

<Effects of the Invention> Since the invention has been described above, the following effects can be obtained.

<a> A cylinder is provided inside the tail plate to secure tail clearance.

Therefore, it is easy to control the digging direction.

<B> Easy curve construction in all directions, especially
It is possible to construct a sharp curve, which was almost impossible in the past.

<C> The direction of the shield machine can be controlled even after the concrete has hardened.

<D> When a pressure resistant bag is used, it is possible to respond to the situation by adjusting the pressure in each bag constituting the pressure resistant bag.

<E> Compared with the existing technology, the inner cylinder can now completely follow the original trajectory with respect to the displacement of the shield machine in all directions.

[Brief description of drawings]

 Fig. 1: Overall view of shield machine according to the present invention Fig. 2: Partially enlarged view of tail part Fig. 3: Cross-sectional view of tail part when there is a single pressure bag Fig. 4: Multiple pressure bags Cross-sectional view of the tail part of the case

Claims (1)

[Scope of utility model registration request] 1. In a cast-in-place type shield machine, an inner cylinder having a diameter smaller than that of the tail plate is attached to the inside of the tail plate so that both ends thereof are independently movable in the tunnel crossing direction. Characteristic, shield machine.