JPH06299785A - Excavation method of tunnel - Google Patents

Abstract

PURPOSE:To make it possible to easily excavate a tunnel having a free shape of section by making excavation with a cutter and, at the same time, injecting high pressure water from an injection-nozzle toward the peripheral part of an excavated hole having a circular section. CONSTITUTION:A cutter on the front end of a shield 11 of a shield machine 1 is rotated around a rotary shaft 1305 extented lengthwise X of the shield 11, and a tunnel 5 is excavated in the ground 3. At that time, high pressure water W is injected from an injection-nozzle 15 placed to a position on the circumference 1105 of the shield 11 toward the peripheral part of a hole having a circular section obtained by rotation of the cutter. A circular area A in a facing 31 is excavated by a cutter disc 1301 and, at the same time, an area B having a required shape is excavated by the high pressure wafer around there.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of excavating a tunnel having an arbitrary sectional shape.

[0002]

2. Description of the Related Art Shielding machines are often used when excavating tunnels underground or in mountains. When excavating with a shield machine, the shield jack provided on the rear part of the shield is brought into contact with the front end of the segment to perform an extension operation, thereby propelling the shield in the excavation direction and excavating at the front end of the shield. There is. There are several types of shield machines, such as a mud pressure type and an earth pressure type. In any of these types, the mainstream is to excavate by rotating a disc-shaped or cross-shaped cutter at the front end of the shield. Therefore, circular cross sections have been the mainstream of tunnels.

However, recently, in order to eliminate the generation of useless space and reduce the section of the tunnel to shorten the construction period, various sectional shapes such as an elliptical shape other than a circular shape, a rectangular shape, a spectacle shape, a triple spectacle shape, etc. Tunnel is appearing. When excavating a tunnel having a cross-sectional shape other than the circular shape, conventionally, a cutter equipped with a planetary gear mechanism or a cutter such as a swing method, a cam method, or a drum rotation method is used, and the center of rotation of the cutter is moved vertically and horizontally. By moving it to, the area around the circular area to be excavated by the cutter with the rotation center fixed was excavated.

[0004]

However, in the above-mentioned conventional method, the moving range of the rotation center of the cutter is limited to the range depending on the opening shape of the shield front end and the shape of the trajectory of the cutter during rotation. Therefore, there was a problem that the shape of the obtained tunnel cross section was limited. In addition, in order to solve the above-mentioned problems, a semi-mechanical digging shield method using a backhoe or a boom cutter, a rectangular shield method, etc. are used, but it can be applied to shield machines such as mud pressure type and earth pressure type. It was hard to say that it was a suitable method such as shining. The present invention has been made in view of the above circumstances, and an object of the present invention is to
An object of the present invention is to provide a tunnel excavation method that can be applied to various types of shield machines such as muddy water pressure type and earth pressure type, and that can easily excavate a tunnel having an arbitrary cross-sectional shape.

[0005]

In order to achieve the above-mentioned object, the present invention provides a method for excavating a tunnel by rotating a cutter at a front end of a shield around an axis extending along the longitudinal direction of the shield. It is characterized in that high-pressure water is jetted toward a peripheral portion of a hole having a circular cross section formed by rotation of a cutter, and the peripheral portion is removed by the high-pressure water to obtain a tunnel having a desired sectional shape.

Further, in the present invention, the high-pressure water is jetted outside the cutter toward the front of the cutter. Further, in the present invention, the high-pressure water is jetted in a direction intersecting with the peripheral surface of the hole having a circular cross section.
Further, in the present invention, the high-pressure water is jetted from the inside of the cutter toward the peripheral surface of the hole having a circular cross section. Further, in the present invention, the high pressure water is jetted together with compressed air.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic diagram showing a main configuration of a shield machine according to an embodiment of the method of the present invention. The shield machine of the present embodiment, which is designated by the overall reference numeral 1 in FIG. 1, is used when excavating a tunnel 5 in the ground 3, and includes a shield 11 and a cutter 1.
3, and the injection nozzle 15. Shield 11
Is formed of a tubular body having an outer shape corresponding to the sectional shape of the tunnel 5, a partition 1101 is provided on the front end side thereof, and a chamber 1103 is defined in the shield 11 on the front end side of the partition 1101. There is.

The cutter 13 is provided at the front end of the shield 11, and is provided at the center of the cutter disk 1301, a disk-shaped cutter disk 1301, a plurality of cutter bits 1303 protruding from the front surface of the cutter disk 1301. The shield 11 has a rotating shaft 1305 extending along the longitudinal direction X of the shield 11. The rotating shaft 1305 is the partition wall 110.
The cutter disk 1301 is rotatably supported at the center of the rotary shaft 130 by a motor (not shown).
5 is driven to rotate in the circumferential direction.

The injection nozzle 15 is disposed near the inner peripheral surface 1105 of the shield 11, and the water supply tube 1
A nozzle head 501 and a nozzle head 1503 are provided. The water supply tube 1501 is supported by a supporting means (not shown) on the peripheral surface 1307 of the cutter disk 1301 and the inner peripheral surface 1 of the shield 11.
It is movably supported in a gap S with respect to 105, and is connected to a water tank (not shown) arranged outside the tunnel 5 or on the rear end side of the shield 11 via a pump (not shown). ing. The nozzle head 1503 is the water supply tube 15
01 is variably connected to the tip end of the nozzle head 1503. Inside the nozzle head 1503, the water fed from the water tank through the water feed tube 1501 is used as high-pressure water W in the form of a spiral jet water from the front end. A flow path (not shown) for ejecting is formed. In addition, 31 in FIG. 1 is a face.

Next, the excavation operation will be described. For example, when the cross-sectional shape of the tunnel 5 is a square as shown in FIG. 2, the shield 11 is formed in a square cross-section according to the shape, and the shield jack behind the shield machine 1 (Fig. The front end of the segment (not shown) is pressed by a not shown) to propel the shield machine 1 and rotate the cutter disk 1301. At the same time, while the water supply tube 1501 of the injection nozzle 15 is appropriately moved within the gap S, the high-pressure water W that has become a jet water flow from the nozzle head 1503 toward the front face 31 of the cutter 13.
Squirt out.

Then, the cutter disk 1301 excavates the face 31 of the circular area shown by A in FIG. 2 and the face 31 of the area shown by B in FIG. 2 that cannot be excavated by the cutter disk 1301 around the area A. As the soil is propelled by the shield machine 1, the gap S in the shield 11
The soil of the face 31 of the area B is excavated by the high-pressure water W ejected from the nozzle head 1503,
As a result, the tunnel 5 having a square cross section is excavated.

The above-mentioned tunnel excavation method is particularly effective in the case of hard geology, but in the case of a clay layer or sandy ground where the geology is soft, the force of the high-pressure water W has entered the gap S. In addition to excavating the soil of the face 31 of the area B, the face 3 of the area B in front of the shield 11 is excavated.
It is assumed that one part of the soil will be excavated and the face 31 will collapse or ground subsidence will occur. Therefore, in the case of soft geology, for example, as shown in FIG.
3 is changed to the direction toward the center of the shield 11 and the direction of the high-pressure water W is changed to excavate the soil of the part of the face 31 shown in the region B in FIG. 2 that has entered the gap S from the outside toward the center of the shield 11. do it.

As another method, as shown in FIG. 4, the injection nozzle 15 is attached to the peripheral surface 130 of the cutter disk 1301.
7 is arranged inside (rotating shaft 1305 side), the nozzle head 1503 is arranged in the radial direction of the cutter disk 1301, and the nozzle head 1503 is arranged in the cutter disk 130.
It may be configured to rotate together with 1. In this case, the high-pressure water W from the nozzle head 1503 has slits (not shown) provided on the peripheral surface 1307 of the cutter disk 1301.
Is ejected from the inner peripheral surface 1105 of the shield 11,
Face 31 shown in area B in FIG.
Part of the soil is excavated from the inside.

In this case, the water supply tube 1501 is connected to the water tank (not shown) and is fixed on the axis of the rotary shaft 1305. The first tube 1505 and the first tube 15
No. 05, a rotary joint 1507 attached to the tip of the first tube 1505, and a second L-shaped tube 1509 connected to the tip of the first tube 1505 via the rotary joint 1507. The cutter disk 1301 and the nozzle head 1503. The second tube 1509 of the water supply tube 1501 following the rotation of
It may be configured such that only one rotates.

Alternatively, the peripheral surface 13 of the cutter disk 1301
A non-rotatable annular member (not shown) is inscribed in the No. 07, and the peripheral surface portion of the annular member and the cutter disk 13 facing this
For example, a groove having a semicircular cross section is formed at each of 1307 of the peripheral surface of 01, and the water supply tube 1501 is formed in the groove on the annular member side.
Is filled with water from a water tank, and the peripheral surface 13 of the cutter disk 1301 is filled with water.
The nozzle head 1503 may be embedded in the cutter disk 1301 in the radial direction of the cutter disk 1301.

Then, as shown in FIG. 5, the nozzle head 1503 is moved toward and away from the peripheral surface 1307 of the cutter disk 1301 to enter the gap S, and the soil of the portion of the cutting face 31 shown by the area B in FIG. The water pressure of the high-pressure water W on the surface may be changed according to the geology of the ground 3.

If the cross-sectional shape of the tunnel 5 is a horizontally long rectangle, a vertically long rectangle, an inverted trapezoid, a regular hexagon, or an ellipse, as shown in FIGS.
1 is formed into a cross-sectional shape corresponding to those shapes, the face 31 of the circular area A shown in FIGS. 6 to 10 is excavated by the cutter disk 1301, and the surrounding area of FIG. High pressure water W jetted from the nozzle head 1503 on the outside of the peripheral surface 1307 of the cutter disk 1301 by causing the face 31 of the area B to enter the gap S.
By excavating in, the tunnel 5 having each of the above-described cross-sectional shapes can be excavated.

Further, instead of the cutter 13 having the disc-shaped cutter disk 1301 shown in FIGS. 1 and 3 to 5, two cross-shaped cutters (not shown) are arranged in parallel at the front end of the shield 11. Then, by rotating each cross-shaped cutter and ejecting the high-pressure water W from the nozzle head 1503 between the cross-shaped cutters and around each cross-shaped cutter, as shown in FIGS. 11 and 12. It is also possible to excavate the tunnel 5 having an elliptical shape or a horizontally long rectangular cross-sectional shape.

Then, if the two cross-shaped cutters are closely spaced so that they do not interfere with each other during rotation and a phase difference is provided in the rotation of the two cross-shaped cutters, as shown in FIG.
It is also possible to excavate the tunnel 5 having a rectangular cross section whose width is shorter than the cross section of FIG. In excavating the tunnel 5 having the cross-sectional shape shown in FIGS. 11 to 13, the face 31 of the area A shown in these figures is excavated by a cross-shaped cutter, and the face 31 of the surrounding area B is cut. The high pressure water W from the nozzle head 1503 is excavated.

As described above, in the shield machine 1 of the present embodiment, the soil around the face face 31 portion excavated by the cutter 13 is excavated by the high pressure water W from the jet nozzle 15, so that the shape of the cutter 13 is changed. It is possible to excavate a tunnel having an arbitrary sectional shape such as a rectangular shape, a rectangular shape, an elliptical shape, etc., without being limited to the corresponding circular sectional shape tunnel.

When the jetting direction of the high-pressure water W is changed to the center side of the shield 11, for example, as shown in FIG. 14, the cylinder 1511, and the jet port 151 provided on the peripheral surface 1513 thereof.
The use of the nozzle head 1517 provided with 5 and 5 is convenient because it is not necessary to change the pointing direction of the nozzle head 1503 to the center side of the shield 11 as shown in FIG. In addition, as shown in FIG.
Of the injection port 1515 of the double structure, one of the injection port 151
High-pressure water W is ejected from 5A and the other ejection port 15
The compressed air R may be jetted from 15B to enhance the efficiency of excavation by the high-pressure water W. If the nozzle head 1503 shown in FIGS. 1 and 3 to 5 is also configured similarly, the high-pressure water W is used. It is possible to improve the efficiency of excavation. The configuration of the shield machine for carrying out the method of the present invention is not limited to that shown in the present embodiment, and it goes without saying that the method of the present invention is applicable to various shield machines such as mud pressure type and earth pressure type. Yes.

[0022]

As described above, according to the present invention, when the cutter at the front end of the shield is rotated about the axis extending along the longitudinal direction of the shield to excavate the tunnel, the cutter is rotated by the rotation of the cutter. Since high-pressure water is jetted toward the peripheral portion of the hole having a circular cross-section to be formed and the peripheral portion is removed by the high-pressure water to obtain a tunnel having a desired cross-sectional shape, a tunnel having an arbitrary cross-sectional shape can be easily formed. It can be excavated and can be applied to various shield machines such as mud pressure type and earth pressure type.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a configuration of a main part of a shield machine according to an embodiment of a method of the present invention.

FIG. 2 is an explanatory diagram illustrating an excavating operation when a tunnel having a square cross section is excavated by the shield machine shown in FIG.

FIG. 3 is a schematic diagram showing a main part configuration of a shield machine according to another embodiment of the method of the present invention.

FIG. 4 is a schematic diagram showing a main part configuration of a shield machine according to another embodiment of the method of the present invention.

5 is an explanatory diagram illustrating an operation when changing the water pressure of the high-pressure water ejected from the ejection nozzle of FIG.

FIG. 6 is an explanatory diagram illustrating an excavating operation when a tunnel having a horizontally long rectangular cross section is excavated by the shield machine shown in FIG. 1, FIG. 3, or FIG.

FIG. 7 is an explanatory view for explaining an excavation operation when excavating a tunnel having a vertically long rectangular cross section by the shield machine shown in FIG. 1, FIG. 3 or FIG.

FIG. 8 shows a tunnel having an inverted trapezoidal cross section.
FIG. 5 is an explanatory view explaining an excavation operation when excavating with the shield machine shown in FIG. 4.

FIG. 9 is an explanatory diagram illustrating an excavation operation when excavating a tunnel having a regular hexagonal cross section with the shield machine shown in FIG. 1, FIG. 3, or FIG.

FIG. 10 is an explanatory diagram illustrating an excavation operation when excavating a tunnel having an elliptical cross section with the shield machine shown in FIG. 1, FIG. 3, or FIG.

FIG. 11 is an explanatory diagram illustrating an excavation operation when excavating a tunnel having an elliptical cross-section with the shield machine shown in FIG. 1, FIG. 3, or FIG.

FIG. 12 is an explanatory diagram illustrating an excavation operation when excavating a tunnel having a horizontally long rectangular cross section with the shield machine shown in FIG. 1, FIG. 3, or FIG.

13 is an explanatory diagram for explaining an excavation operation when excavating a tunnel having a rectangular cross section whose lateral width is shorter than that of FIG. 12 by the shield machine shown in FIG. 1, FIG. 3 or FIG.

FIG. 14 is a perspective view showing a main configuration of a shield machine according to another embodiment of the method of the present invention.

[Explanation of symbols]

 1 Shield machine 11 Shield 13 Cutter 1305 Rotating shaft R Compressed air W High pressure water X Shield longitudinal direction

Claims (5)

[Claims] 1. When excavating a tunnel by rotating a cutter at a front end of a shield around an axis extending along the longitudinal direction of the shield, the cutter is provided at a peripheral portion of a hole having a circular cross section formed by rotation of the cutter. A method of excavating a tunnel, characterized in that high-pressure water is jetted toward the high-pressure water to remove the peripheral portion to obtain a tunnel having a desired cross-sectional shape. 2. The method for excavating a tunnel according to claim 1, wherein the high-pressure water is sprayed outside the cutter toward the front of the cutter. 3. The method for excavating a tunnel according to claim 1, wherein the high-pressure water is jetted in a direction intersecting a peripheral surface of the hole having a circular cross section. 4. The method for excavating a tunnel according to claim 3, wherein the high-pressure water is jetted from the inside of the cutter toward the peripheral surface of the hole having a circular cross section. 5. The tunnel excavating method according to claim 1, 2, 3, or 4, wherein the high-pressure water is injected together with compressed air.