JPH06173576A - Preparatory method for pretreating work such as soil improvement in excavation of tunnel - Google Patents

Abstract

PURPOSE:To smoothly perform a preparatory work such as soil improvement in the excavation of a tunnel by inclining a cutter head through an angle and forcing chemical liquid such as accelerator through a gap provided between the cutter head and the wall of a shaft. CONSTITUTION:A cutter head 10 of an excavation machine has a construction such that the cutter head 10 can be inclined through any angles, and the head 10 is inclined through required angles after the excavation of certain span to provide a gap (h) between the upper or lower end of the head and the wall 7 of a shaft. Next, a boring machine 43 mounted to a base 41 fixed on a main frame 20 through cylinders 42, 44 is actuated to form a boring hole 40 through the upper surface of the facing at required point so that cement milk and accelerator are forced through the gap (h). The cylinders 42, 44 impart vertical motion and inclining motion to the boring machine 43. In this manner soil improvement is achieved and then excavation is restarted by means of a tunnel boring machine.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a construction method for preparing a pretreatment work such as ground improvement, preparatory work, or ground exploration in front of a face to be excavated.

[0002]

2. Description of the Related Art Generally, in the shield construction method, a tunnel boring machine that excavates a gripper as a reaction force when the ground is strong such as rock, or a tunnel lining part such as a segment or cast in a soft ground is used as a reaction force. A shield machine that excavates, or recently, a machine that has both of these machines is used. All of these excavators excavate the tunnel by excavating the cutter surface while rotating the cutter head, but in the middle of that, they perform forward exploration of the excavated ground and, in some cases, forefront work such as fore piling and ground improvement. Pre-processing work such as

In order to perform this pretreatment work, the excavator is largely retracted from the face of the face, and when it comes out to the face of the face and then the side shaft or the upper shaft is bored by hand digging or blasting. As shown in FIG. 3, after performing the diagonal front boring 40 from the rear of the cutter head 10, the ground 7
In some cases, ground improvement such as press-fitting the chemical solution 8 was performed.

[0004]

However, the above-mentioned conventional work on the front face of a face has a defect in safety, which affects work efficiency and causes a problem in terms of construction period and economy.
In addition, if the ground is improved after drilling diagonally forward, the chemical solution may be injected to a wasteful area during excavation, or the position of the transmitter in the borehole may be insufficient, resulting in unreliable ground exploration. There were challenges.

The present invention has been made in order to solve these problems, and its purpose is to improve the efficiency of excavation work and to accurately perform pretreatment work for excavation such as ground improvement. To provide a preparatory method for pretreatment work in excavation.

Another object of the present invention is to prepare a pretreatment work for tunnel excavation, which enables rapid pretreatment work by a simple means without largely changing the basic structure of a conventional excavator. I will provide the construction method.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above objects, and its gist is a device body and a cutter rotatably supported by the device body and having a cutter surface on the front surface in the excavation direction. Using an excavator equipped with a head and a tilting means for tilting the cutter head at an arbitrary angle with respect to the excavation direction, the angle of the cutter head is tilted in the front-rear direction, and the upper or lower end of the cutter head and the pit wall By providing a gap in the ground and drilling a boring hole in the ground in the tunnel line where the excavation is planned, the boring hole can be used for pretreatment work such as ground improvement, pre-treatment, or ground exploration. It is in the preparatory method for pretreatment work such as ground improvement in tunnel excavation.

[0008]

In the present invention, the tilting means is used to incline the angle perpendicular to the tunnel excavation axis forward or backward in the front-rear direction to provide a clearance between the upper or lower end of the cutter head and the pit wall. A boring hole is drilled and pre-excavation processing such as ground improvement is performed from the drilled hole.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preparatory method for pretreatment work in tunnel excavation according to the present invention will be described below with reference to a tunnel boring machine as an excavator used in the present invention.

A tunnel boring machine as one of the excavators used in the present invention will be described as an example with reference to the accompanying drawings.

In FIG. 1, a tunnel boring machine comprises a cutter head 10 located in front of the excavating direction.
A main frame 20 as a device main body that supports the cutter head 10 and a gripper portion 30 for taking a reaction force for excavation constitute a main part.

The cylindrical cutter head 10 has a circular cutter surface 11 on the front surface in the excavation direction, and the cutter surface 11
Is equipped with a large number of excavating cutters 12, and the electric motor 14 rotationally drives the cutter head 10 to excavate the ground. Further, the cutter head 10 is tiltably supported by the main frame 20 behind the cutter head 10 via a connecting rod 21 ′ of the movable connecting portion 21.

A box-shaped main frame 20
Is a tilting cylinder 2 for tilting the cutter head 10.
6, and a gripper portion 30 slidably fitted to the main frame 20 is arranged at the rear portion. The tip of the tilting cylinder 26 is the cutter head 1.
It is fixed to the lower end of 0, and the cylinder of the tilting cylinder 26 is expanded and contracted so that the cutter drum 1
0 rotates up and down around the connecting rod 21 'of the movable connecting portion 21, and the inclination angle of the cutter surface 11 with respect to the excavation direction can be set arbitrarily. Further, a rear support 23 for supporting the main frame 20 from below when the fixing by the gripper portion 30 is released is arranged at the rear end of the main frame 20, and the rear support 23 is a cylinder support. It is a mechanism that can be expanded and contracted depending on the structure. A belt conveyor 22 is fixed to the side portion of the main frame 20, and the cutter head 10
The cutting scraps scraped up by the scraping plate 13 provided on the above are dropped onto the belt conveyor 22 and conveyed to the rear side.

The gripper section 30 is a main frame 20.
Is provided with a gripper cylinder 31 projecting elastically on both sides in the horizontal direction, and a gripper shoe 32 curved in an arc shape along the pit wall 7 is arranged at the tip end thereof. When taking the reaction force for excavation, the gripper cylinder 31
Is extended and the pit wall is pressed by the gripper shoe 32 to fix the gripper portion 30 at this position. In addition, the base end portion of the thrust cylinder 24 is connected to the gripper portion 3
It is fixed to 0 and the tip is fixed to the main frame 20 side as the machine body. When excavating, by extending the thrust cylinder 24, a reaction force is applied to the gripper part 30 fixed as described above, and Frame 2
The cutter drum 10 is moved forward integrally with zero.

Further, the tunnel boring machine has
There is a cutter head support 15, which advances along with the excavation of the cutter head using the gripper portion 30 as a reaction force, and supports the tunnel boring machine with the rear support 23 after the excavation. A process of excavating a tunnel by the tunnel boring machine A configured as described above will be sequentially described.

First, the tilting cylinder 26 is expanded and contracted so that the cutter head 10 is tilted upward and forward with respect to the excavation direction at a predetermined angle so that the excavated cross section has a predetermined elliptical shape.

Simultaneously with or before or after this step, the gripper cylinder 31 is extended horizontally on both sides, and the pit wall is pressed by the gripper end 32 to fix the gripper portion 30. The initial position of the gripper portion 30 at the start of excavation is located at the position indicated by the broken line with reference numeral 30 'in FIG. At this time, the rear support 23 at the rear end is in a contracted state.

Next, the cutter head 10 is rotationally driven by the electric motor 14, the thrust cylinder 24 is extended, and a reaction force is applied to the fixed gripper portion 30 to move the cutter head 10 forward. As a result, the gripper portion 30 maintains the fixed position, and the cutter head 10 moves forward together with the main frame 20.

The excavation is continued in this manner, and the excavation is temporarily stopped at the time when the excavation is carried out over a predetermined span. At this time, the rear support 23 at the rear end is extended so that the main frame 20 can be supported. Then, the gripper cylinder 31 is contracted to release the gripper unit 30 from being fixed.
At this time, the main frame 20 is supported by the rear support 23. Next, the thrust cylinder 24 is contracted, and the gripper portion 30 is moved to the above-mentioned initial position (reference numeral 30 ') to prepare for the next excavation. By repeating such a process, the tunnels are sequentially excavated.

As described above, when the tunnel is excavated by the vertically inclined cutter surface 11, the excavated section 61 has a horizontally long elliptical shape suitable for road construction. This oval shape is a horseshoe-shaped tunnel section 6 to be constructed.
The shape is extremely close to 0, and there is a wasteful extra part 62
Can be reduced. It should be noted that if the tilting cylinder 26 is expanded or contracted, the setting of the tilt angle of the cutter head 10 can be changed to excavate into an elliptical shape. In this case, the cutter head support 1 that supports the cutter head 10 from below is used.
5, the inclination of the connecting portion between the cutter head 10 and the cutter head 10 also changes, so the cutter head support 15 and the cutter head 1
An inclination adjusting table 16 is interposed between the tilt adjusting table 16 and 0. It is preferable that the tilt adjusting table 16 is formed in various ways according to the tilt angle.

Therefore, in the present invention, pretreatment work using the above-mentioned tunnel boring machine, for example, improvement of the ground to be excavated will be described.

First, the lower portion of the cutter head 10 which is orthogonal to the excavation axis is retracted forward, and a gap h is provided between the upper end of the cutter head 10 and the pit wall 7.

Then, a boring machine 43 mounted via cylinders 42 and 43 is driven on a pedestal 41 fixed on the main frame 20 of the tunnel boring machine to form a boring hole 40 at a required position on the upper face of the face. The cylinders 42 and 43 adjust the vertical movement and tilting movement of the boring machine 43.

In this way, the same boring machine 43
Inject a chemical liquid such as cement milk or quick-setting adhesive from around the nozzle at the tip of. This chemical liquid injection also serves as a boring machine as shown in FIG. 1, but a separate injection device may be used.

In this way, excavation of the tunnel boring machine is restarted after the ground has been improved to prevent spouting of groundwater and collapse of the ground into the tunnel.

In the present invention, in addition to ground improvement as a pretreatment work, an ultrasonic transmitter or receiver for ground exploration is mounted in the boring hole 40 by the ground improvement preparatory method, and the ground is excavated in the direction of excavation. You can also research in advance.

In the drawing of the above embodiment, as shown in FIG. 2, the lower part of the cutter head is lowered rearward so that a gap is provided between the upper end of the cutter head 10 and the pit wall. Although it is moved forward, it is also possible to perform a pretreatment operation after tilting the upper part of the cutter head forward or backward to leave a gap between the pit walls.

[0028]

According to the present invention, the cutter head of an excavator can be tilted at an arbitrary angle, and by tilting the cutter head in the front-rear direction, a gap is provided between the upper or lower end of the cutter head and the pit wall. Since the boring hole as a preparatory work for pretreatment work such as ground improvement is drilled forward, the work is safe and efficient, and ground improvement and ground exploration can be performed accurately.

In addition, this working method enables quick ground improvement etc. by a simple operation such as adjusting the cutter head of the excavator to an arbitrary angle.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an excavator explaining a method of the present invention.

FIG. 2 is an explanatory view of a tunnel cross section showing a state of a gap between the cutter head and the pit wall when the cutter head of the excavator of FIG. 1 is inclined.

FIG. 3 is a schematic view showing a pre-excavation processing state of an excavator by a conventional method.

[Explanation of symbols]

 8 Chemicals 10 Cutter head 20 Main frame 30 Gripper part 40 Boring hole 43 Boring machine h Gap between cutter head and pit wall

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Takahiro Fujii 2-10-2 Otowa, Bunkyo-ku, Tokyo Otowa NS Building 7F, Advanced Construction Technology Center (72) Inventor Shin Terauchi 2-Kita-Aoyama, Minato-ku, Tokyo 5-8 Ma Ingumi (72) Inventor Yoshiaki Ishida 4-12-20 Nihonbashihonmachi, Chuo-ku, Tokyo Sato Kogyo Co., Ltd. (72) Inventor Yoshito Minami 3-1-1 Ueno, Hirakata, Osaka Komatsu Ltd. Osaka factory

Claims (1)

[Claims] 1. A device main body, a cutter head rotatably supported by the device main body and having a cutter surface on the front surface in the excavation direction, and tilting means for inclining the cutter head at an arbitrary angle with respect to the excavation direction. Using an excavator provided, the angle of the cutter head is inclined in the front-rear direction to provide a gap between the upper or lower end of the cutter head and the pit wall, and a boring hole is dug into the ground in the tunnel line to be dug from the gap. A preparatory method for pretreatment work such as ground improvement in tunnel excavation in which the boring hole is used for preconditioning work such as ground improvement, preparatory work, or ground exploration by drilling the hole ahead.