JPH0437917B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a tunnel excavating machine for excavating a road tunnel having a rectangular cross section, and particularly to a tunnel excavating machine suitable for excavating a tunnel capable of providing multiple lanes.

[Background of the invention]

When constructing a road tunnel with a rectangular cross section that can accommodate multiple lanes, for example, six lanes, using the shield construction method, conventionally, a tunnel excavation machine with a plurality of circular cutter foils arranged side by side in front of the shield body is often used. However, in this tunnel excavating machine, the face surface is excavated by rotation of each cutter wheel, so that the excavation cross section becomes as shown in FIG. 5. In other words, for the rectangular profile A to be excavated, excavation by each cutter foil results in a circular profile opening, resulting in a large amount of unexcavated portion C, resulting in the problem of a sharp increase in excavation resistance. In addition, in this tunnel excavation machine, a muddy water chamber is formed in front of the bulkhead of the shield body, and the face is held only by pressurizing the muddy water in the muddy water chamber, so that the face face has a large cross section. , and the soil quality of the face is in alternating layers, and the self-sustainability or collapsibility of the upper and lower, left and right faces is different (this situation becomes more common when the face has a large cross section)
In this case, it becomes difficult to maintain the face using only the muddy water pressurization. If even a part of the face collapses, the collapse will spread to the entire section, causing construction to be interrupted.

[Purpose of the invention]

The purpose of the present invention is to reduce the propulsion resistance by reducing the unexcavated portion, and to stably maintain the face even if the self-supporting or collapsibility of the face is not uniform, and to perform tunnel construction smoothly. Our goal is to provide tunnel boring machines that allow for tunnel excavation.

[Summary of the invention]

The present invention employs a plurality of drum cutters as excavation cutters, and by arranging these drum cutters vertically, horizontally, and close to each other on the front side of the bulkhead of the shield body, the rectangular cross section to be excavated can be formed. By performing excavation that approximates the contour of the tunnel to reduce unexcavated parts, and by giving the drum surface of the drum cutter group the function of a face plate, the face plate is stably held by the face plate and the muddy water pressurization in the muddy water chamber. This is how it was done.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 1 to 3. FIG. 1 is a longitudinal sectional view of a tunnel boring machine according to the present invention, FIG. 2 is a sectional view taken along the line A-A in FIG. 1, and FIG. 3 is a front view of FIG. Both the figures and FIG. 3 show only one half. In the figure, 1 indicates an immersed burial box, and 2 indicates a shield body connected to the front part of the immersed burial box 1. This shield body 2 has a rectangular cross section, and has a partition wall 3 on the front that separates the face side from the inside of the shield body.
and a hood 4 protruding forward from the partition wall 3 on the outer periphery. Further, the shield main body 2 is provided with a plurality of drum cutters 5 on the front side of the partition wall 3, each of which has a large number of digging blades 5a attached to the drum surface. These drum cutters 5 are arranged vertically, horizontally, horizontally, and close to each other, and are placed so that each rotating shaft 5b becomes a horizontal axis. The number, number of rows, and drum length of these drum cutter groups are selected so that excavation can be performed with a contour substantially equal to the contour of a tunnel with a rectangular cross section to be excavated. The illustration shows an example in which four drum cutters are arranged in a vertical line, and nine such lines are provided. Further, a muddy water chamber 6 is formed between the back surface of the drum cutter group and the partition wall 3 of the seed body 2 to hold the face by pressurizing the muddy water. The partition wall 3 is provided with a support member 7 disposed between the side surfaces of the drum cutters 5 adjacent to each other. This support member 7 is formed of a continuous wall for each column of drum cutters 5, and rotatably supports the rotating shaft 5b of each drum cutter 5. Rotating shaft 5b of each drum cutter 5 in each row (left and right rows)
are located coaxially and are connected to each other via a shaft joint 8 within the support member 7.
Further, each of the above-mentioned support members 7 is provided to protrude from the rear surface of the partition wall 3, and a driving machine 9 for rotating each drum cutter 5 is attached to the protruding support member 7. As this drive device 9, a hydraulic motor or an electric motor is used. Power is transmitted from each drive machine 9 to each drum cutter 5 through a sprocket 10 attached to the rotation shaft 9a of the drive machine 9 and a sprocket 11 attached to the rotation shaft 5b of the drum cutter 5.
and chain 12 that runs around both sprockets.
It is now being done through These sprockets 10, 11 and chain 12 are housed inside the support member. Therefore, each drum cutter 5 in each row has its corresponding drive machine 9.
It is rotated by the total driving force of. When excavating the face, the drum cutters 5 in each row are rotated in the direction of the arrow shown in FIG. 1 to take the excavated earth and sand into the muddy water chamber 6. Furthermore, a bit 13 is provided at the tip of each support member 7 for crushing large lumps of excavated earth and sand that enter between the sides of the drum cutter 5, and the cutting edge of the bit 13 is slightly smaller than the front excavation blade 5a of the drum cutter 5. Located at the rear.

On the other hand, the muddy water chamber 6 is vertically divided into a plurality of parts by support members 7 forming continuous walls. is provided. Further, a face plate is formed on the drum surface of the drum cutter group on the face surface side of the muddy water chamber.

Next, the operation of excavating a tunnel according to this embodiment will be explained.

First, a tunnel excavator and a submerged box 1 are installed at the bottom of a vertical hole dug underground as shown in FIG. Next, water is sent from the water pipe 14 to each muddy water chamber 6, and while the face is maintained by muddy water processing, the group of drum cutters on the front of the shield body 2 is rotated, and a propulsion force is applied to the immersion box 1 via a propulsion jack or the like. do. As a result, as shown in FIG. 4, the shield body 2 and the immersed box 1 are propelled while the drum cutters excavate the face, and a tunnel with a rectangular cross section is constructed. The excavated earth and sand is taken into the mud water chamber 6 and discharged to the ground together with water from the mud drainage pipe 15.

In this tunnel construction, the drum cutter group can excavate a face with a contour that approximates the cross-sectional rectangular contour of the tunnel to be excavated, so there is extremely little left unexcavated, and propulsion resistance is significantly reduced. In addition, even if the self-supporting or collapsibility of the face is uneven, the face can be held by pressurizing the muddy water in the muddy water chamber 6 and by the face plate formed on the drum surface of the drum cutter group on the muddy water chamber face side. , the face can be held stably at all times. Further, in this embodiment, the muddy water chamber 6 is divided into a plurality of parts, and each of the muddy water chambers independently supplies water,
Since mud can be drained, face retention can be further stabilized by adjusting the mud water pressure in the mud water chamber facing the face with poor self-sustainability. Furthermore, since a bit 13 is provided at the tip of the support member 7 that supports the drum cutter 5, even if a large lump of excavated soil tries to enter between the sides of the drum cutter, it will be crushed by the bit 13. The excavated soil remaining in the trench can be dispersed into muddy water.

In this embodiment, each drum cutter 5
Although an example has been shown in which the drum cutters are arranged so that the rotation axis 5b becomes the horizontal axis, each drum cutter may be arranged so that the rotation axis 5b becomes the vertical axis. Further, in this embodiment, an example is shown in which the drum cutters 5 in each row are rotated in a connected state, but a configuration may be adopted in which each drum cutter 5 in all rows is rotated independently.

〔Effect of the invention〕

As described above, according to the present invention, when constructing a tunnel with a rectangular cross section, the propulsion resistance can be reduced by reducing the unexcavated portion, and the face can be stably maintained even if the self-sustainability or collapsibility of the face is uneven. You can do it by doing this.

[Brief explanation of drawings]

1 to 3 show one embodiment of the present invention, FIG. 1 is a longitudinal sectional view of a tunnel boring machine according to the present invention, FIG. 2 is a sectional view taken along the line A-A in FIG. 1, and FIG.
The figure is a front view of figure 1 seen from direction B, figure 2,
In each case, FIG. 3 shows only one half. Figure 4 is a schematic diagram showing the tunnel being excavated, Figure 5
The figure shows a cross-sectional view of a face excavated by a conventional tunnel boring machine. 1... Submerged box, 2... Shield body, 3... Bulkhead, 5... Drum cutter, 5a... Excavation blade, 5b
... Rotating shaft, 6 ... Mud water chamber, 7 ... Support member, 9 ... Drive machine, 10, 11 ... Sprocket, 12 ... Chain, 13 ... Bit, 14 ...
...Water pipe, 15...Mud water pipe.

Claims (1)

[Scope of Claims] 1. A tunnel excavating machine for excavating a tunnel with a rectangular cross section, which comprises a shield body with a rectangular cross section connected to the tip of an immersed burial box, and vertically and horizontally aligned on the front side of a bulkhead of the shield body. a plurality of drum cutters disposed close to each other; a driving machine for each drum cutter installed behind the bulkhead of the shield body; and a side surface of the adjacent drum cutters installed on the bulkhead of the shield body. A support member disposed in between, a mud chamber formed between the back of the drum cutter group and the bulkhead of the shield body, which holds the face by pressurizing mud, a water pipe that supplies water to the mud chamber, and a water pipe inside the mud chamber. a sludge removal pipe for removing sludge, the rotating shaft of each drum cutter is rotatably supported by the support member, and
A tunnel excavating machine characterized in that a power transmission mechanism from a driving machine to a drum cutter is disposed inside the support member, and a face plate is formed on the mud water chamber face side of the drum surface of the drum cutter group. 2. In claim 1, each drum cutter is arranged such that its rotational axis is a horizontal axis, and the rotational axes of each drum cutter in each row are connected to each other at a support member, while the rotational axis of each drum cutter in each row is The member is formed by a continuous wall for each column of drum cutters,
A tunnel excavating machine characterized in that the muddy water chamber is divided into a plurality of parts by its support member, and each muddy water chamber is provided with a water supply pipe and a mud removal pipe that independently supply water and remove mud. 3. In claim 1, a bit is formed at the tip of the support member to crush excavated earth and sand that enters between the sides of the drum cutter, and the cutting edge of the bit is slightly rearward of the front cutter surface of the drum cutter. A tunnel boring machine characterized by being located in