JP2604217B2 - Construction method of branch road by shield machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to, for example, a tunnel being constructed by a double shield construction method combining two shield excavators,
Separate the two shield excavators as needed,
The present invention relates to a method for constructing a branch furnace.

<Prior Art> A double shield having two shield excavators integrated with each other is used for construction of underground railways, roads, and the like.

In this way, with the apparatus, simultaneous construction of the upper and lower railway lines is possible.

<Problems to be Solved by the Present Invention> When constructing a subway or the like with a double shield excavator, in an island-shaped platform, the upper and lower lines must be branched to both sides of the platform.

However, the current twin shield excavator can only build a structure in which the upper and lower lines travel in parallel, and cannot cope with the construction of a structure in which the upper and lower lines are branched separately.

For this reason, in the past, giving up the excavation with a twin shield excavator only near the platform, excavating a large area from the ground, and performing construction from the branch part to the junction part.

However, due to recent land shortages and an increase in the amount of traffic on the ground, it is becoming difficult to construct a large area from the ground.

<Object of the present invention> The present invention has been made in order to solve the above-mentioned problems. In subways, underground roads, and other underground structures, branching or merging work is performed from the ground. It is an object of the present invention to provide a method that can be directly constructed by a shield machine without performing excavation.

<Configuration of the Present Invention> Next, an embodiment of the present invention will be described.

<A> Shield machine used The shield machine used in the method of the present invention has a double structure as shown in FIG. 2, for example.

Each shield machine 1 is composed of a circular wall 11 and a plane wall 12, each of which has a circular cross section with a part cut away.

The connection surfaces, which are the flat walls 12 of the two cut-out machines, are disassembled with bolts or the like to form an integrated double shield excavator.

 A known method can be used for excavation of each excavator.

For example, when the rotary blades 2 for excavation are used in the front part of the fuselage, the trajectories of both rotary blades 2 overlap, so that the rotation positions are shifted like gears so as not to collide.

<B> Integral excavation When excavating in a state where the two shield excavators 1 are integrated, it is the same as the construction of the conventional double shield excavator.

That is, the segment 3 is assembled at the rear inside the fuselage,
The aircraft is advanced by taking a reaction force to the third group of segments.

The shape of the segment 3 after assembly is similar to the outer diameter of the excavator 1 and is a partially overlapped double circle, and a pillar 31 and a wall are provided at the center. (Fig. 3) <c> Separation Upon reaching a predetermined position, separation is performed.

For this purpose, the joint between the two is released by, for example, disassembling the bolt between the connection surfaces that are the flat walls 12.

Then, by biasing the way of taking the reaction force to the segment 3, the two are gradually separated from each other.

<D> Deformed segment The shape of the segment 3 after the two are separated from each other again has a shape in which a part of a circle is cut out. (FIG. 4) In this case, since the blade 2 at the front end of the body is rotating, a circular cross section is excavated.

On the other hand, since segment 3 is non-circular, segment 3
The portion of the earth and sand S that has not been taken in remains on the outside of the plane wall 32 of the segment 3 merely by stirring.

Therefore, in some cases, cement milk may be injected into the earth S and left from the inside of the segment 3 to reinforce it.

<E> Other Embodiments The case where the two shield excavators are connected with the plane wall 12 as the connection surface has been described above. However, as shown in FIG. The method of the present invention can be carried out even when the connection is made at 13.

In the drawing, the method of separating the shield machine into left and right on the same plane was explained.However, when the shield machine is vertically separated on the same vertical plane, or when both are mixed and separated obliquely, the same construction should be performed. Can be.

Also, the case of separation has been described above, but after separation, the connection surface that is a flat wall is gradually approached again, and finally a method of connecting integrally, or starting from another point and connecting later It can also be used for such methods.

<Effects of the Present Invention> Since the present invention has the above-described configuration, the following effects can be achieved.

<A> Separation of the course can be performed without excavating the earth from the ground without excavating the shield.

Therefore, even in a city where it is difficult to obtain land on the ground, the work can be performed without affecting the ground.

<B> Particularly in the case of constructing deep underground, the method of the present invention is extremely effective, because excavation from the ground is almost impossible.

<C> Since the work can be performed only by shield excavation work without the need for excavation work from the ground, the construction period can be shortened as compared with the case where the work is combined with different kinds of work.

<D> In the conventional technology, a plurality of shield machines are combined in a parallel integrated type, and after propulsion is integrally performed to a predetermined position, a wall body is cut off at each connection portion of each shield machine while being made on-site. There is a shield construction method using a multi-core parallel integrated shield machine that excavates tunnels
268991).

However, according to this method, when the shield machine is separated, a partition wall is provided at each connection portion in a narrow tunnel at the site, and the connection portion of the shield machine must be closed, so that it takes time and labor.

On the other hand, according to the present invention, since the wall of the entire outer periphery is prepared in advance in a factory or the like, it is not necessary to prepare a wall at a connection portion of the shield machine at the site when the shield machine is separated.

Therefore, the construction period can be shortened, and the construction cost can be reduced.

<E> The connection of the shield machine by the above-mentioned conventional method is to connect the edges of the cutouts of the shield machine, and because the connection is made by wires, the joint area is small, and it is soft against external force. Connection.

On the other hand, in the present invention, a part of the wall is used as a connection surface,
Since the two shield excavators are integrated by matching these surfaces to each other, the connection area is large, and a connection that is strong against external force can be made.

<F> In addition, the conventional construction method is a horizontally long elliptical shield machine that has no wall at the connection, so it is weak against vertical earth pressure and is not suitable for sites with large earth pressure resistance. is there.

On the other hand, the present invention is a shield machine in which the entire outer periphery is surrounded by a wall body, and is substantially circular.

<G> Furthermore, in the conventional method, since a plurality of shield machines are connected by the cutouts in the outer peripheral portion, since the entire outer periphery of each shield machine is not surrounded by the wall body, there is a possibility that the waterproofness of each connected portion may be reduced. There is.

For this reason, a separate reinforcing structure for securing the waterproofness of the connection part of each shield machine is required.

On the other hand, according to the present invention, since the entire outer periphery of each shield machine is surrounded by the wall, even if a plurality of shield machines are connected, the connection portion of the shield machine has perfect water blocking properties.

[Brief description of the drawings]

FIG. 1: Illustration of an embodiment of the construction method of the present invention FIG. 2: Illustration of a shield machine to be constructed according to the invention FIG. 3, 4: Illustration of segments before and after separation FIG. : Explanatory drawing of another embodiment

Claims (1)

(57) [Claims] The present invention relates to a fork of a shield excavator, wherein two shield excavators are connected and propelled integrally, and then separated at a predetermined position and propelled by applying a reaction force to a segment. In the construction method, each shield machine is configured to surround the entire outer periphery with a wall in advance before the propulsion by the two units, and a part of the outer surface of the wall conforms to the shield shield machine of the other party. A method for constructing a fork by a shield machine, wherein a connection surface for connecting the terminals is provided.