JPH0365478B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention is directed to tunnel excavation, which enables the safe installation of shoring while securing the ground near the top of the excavated inner surface to prevent falling rocks and collapse. It's about machines.

[Prior Art] A self-propelled tunnel excavation machine uses a gripper or the like disposed on a shield body to generate a reaction force for digging by generating friction between the outer surface of the body frame and the excavation inner surface. , a plurality of blades are arranged around the outer periphery of two strong circular frames, front and rear, and each blade slides on the guide surface of the frame, and the reaction force applied to the blade when press-fitting into the face is absorbed by the soil applied to the other blades. The blades are advanced one after another using pressure and the friction force due to the machine's own weight as a reaction force, and after all the blades have been advanced, the front and rear frames are pulled forward to dig (the so-called Metsu cell blade tunnel machine).
etc.

The primary lining of this self-propelled tunnel boring machine is
Instead of installing segments on the inside of the excavation, steel shoring is installed on the inside of the excavation, auxiliary material such as wire mesh is attached between the installed shoring and the existing shoring, and then concrete is sprayed. many.

In this case, if the shoring is installed on the inner surface of the excavation at a distance from the main frame, the distance between the main frame and the last installed shoring will be longer, and rocks will fall from near the top of the ground between the two. It is dangerous for workers as there is a risk of collapse, etc. If there is a falling rock or collapse, a cavity will be created in the area and the cavity must be filled with concrete, which increases the amount of concrete sprayed and causes secondary damage. Since it is necessary to perform backfill injection after constructing the lining, construction costs may increase and the cost may become longer. Therefore, shoring, including auxiliary materials (wire mesh, etc.), must be installed on the inside of the excavation immediately behind the main frame.

In addition, since the spacing between the shoring is generally around 1m, it is also possible to prevent the ground from loosening, falling rocks, and collapsing near the top of the inside of the excavation between the last shoring installed and the previous shoring. is important.

[Problems to be Solved by the Invention] However, in the conventional method, the shoring is installed by a shoring installation device installed behind the main body frame, so the shoring is installed at a remote position behind the main body frame. However, no shoring was installed on the excavated inner surface immediately behind the main body frame.

For this reason, there is an extremely high risk of rocks falling or collapsing near the top of the excavated inner surface between the rear part of the main body frame and the last installed shoring. It was also impossible to deal with the loosening of the mountains near the edges.

In addition, in the conventional construction method, if there is a risk of collapse near the top of the inside surface of the excavation, it is necessary to drive a lock bolt in advance immediately after the rear of the main body frame to ensure safety; Since there is no guard, driving the lock bolt is extremely dangerous, and the work area cannot be secured, making it extremely difficult to drive the lock bolt immediately after the rear of the main body frame.

The present invention prevents falling rocks and collapses by resting the ground directly behind the main body frame, and easily locks bolts against the ground that is likely to collapse while ensuring safety in advance. It is designed so that you can type .

[Means for Solving the Problems] In the present invention, a support frame is fixed to a fixed frame within the tunnel excavating machine main body frame so as to protrude rearward of the main body frame, and the fixed frame is fixedly mounted on the support frame. A scaffold is provided that can be moved back and forth by a moving jack installed on the frame, and a ground holding jack, an arc-shaped ground holding frame supported by the ground holding jack, and a rotating ground holding frame. A rock retaining device consisting of a rock retaining plate that can be attached to drill a lock bolt driving hole; a shoring installation device comprising a shoring jack and a shoring gripper supported by the shoring jack; The mechanism is mounted on the scaffold.

[Function] Therefore, the shoring is installed immediately after the main body frame while the ground is secured by the ground securing device.

[Example] Hereinafter, an example of the present invention will be described with reference to the drawings.

Figure 1 shows the structure of the rear end of a tunnel excavator.A support frame 3 is attached to the rear of a fixed frame 2 disposed within the excavator body frame 1 in the form of a cantilever so as to protrude rearward. A guide rail 4 and rollers 5 are fixedly installed on the support frame 3.
A scaffold 6 is placed so as to be movable in the front and back direction (propulsion direction) through the frame 2, and a moving jack 7 for moving the scaffold 6 is installed on the fixed frame 2. scaffolding 6
As shown in FIG. 2, the front part of the machine is equipped with shoring installation jacks 9 equipped with shoring gripping tools 8 at left and right positions on the upper surface as a shoring installation device, and similar shoring gripping tools 8. Shoring expansion jacks 10 are provided on both sides, respectively. On the other hand, on the left and right positions of the rear upper surface of the scaffold 6, as a mountain land securing position, a ground holding jack 12 equipped with an arc-shaped ground holding frame 11 is installed as shown in FIG.
At the front upper end of 1, as shown in FIGS. 4 and 5, a rock retaining plate 14 of a required length with lock bolt driving holes 13 is attached to the plate 14 so as to be rotatable in the vertical direction with pins 15. An operating jack 16 for rotating the rock retaining plate 14 is attached to the lower part of the rock retaining frame 11. A plurality of the rock retaining plates 14 are arranged at required intervals according to the circular arc shape of the rock retaining plate frame 11.

In addition, in Fig. 2, 17a is a split support;
7b is the key shoring, and these split shoring 17
Joint plate 1 provided on each end face of a and key support 17b
By tightening 8 and 18 with bolts 19 as shown in FIGS. 6 and 7, a ring-shaped integrated shoring 17 is constructed.

Next, the operation will be explained with reference to FIGS. 8A to 8D.

First, as shown in FIG. 8A, the shoring 17' is temporarily assembled in advance within the rear part of the main body frame 1 using a shoring temporary assembling device (not shown) (an erector may be used). That is, without attaching the key support 17b, each divided support 17a is connected in a ring shape with the bolts 19 between the joint plates 18, 18 loosened and stored in the rear part of the main body frame 1, and then temporarily An auxiliary material 20 such as a wire mesh is placed on the upper part between the assembled shoring 17' and the last assembled shoring 17.

Next, as shown in FIG. 8B, the moving jack 7 is retracted so that the shoring gripping tools 8 of the shrunk jacks 9 and 10 are positioned inside the temporarily assembled shoring 17'. After that, Jyatsuki 9,10
are extended and each shoring gripper 8 grips the shoring 17' as it is. In this state, when the moving jack 7 is extended at the same speed as the excavation speed of the excavator, the rock holding frame 11 comes out immediately after the main frame 1. At this point, the ground retention jack 1
Extend 2 and remove the ground 2 near the top of the inner surface of the tunnel excavation.
1 is secured by the earth holding frame 11.

Furthermore, as shown in FIG. 8C, when the excavator advances and a space is created where the rock retaining plate 14 can be used, the operating jack 16 is extended to push the rock retaining plate 14 toward the rock 21. 21 will be secured. Further, in this state, the lock bolt 22 can be driven into the ground 21 from the lock bolt driving hole 13 drilled in the holding plate 14, if necessary, using the scaffold 16.

The excavator further moves forward, and as shown in Figure 8D, the shoring machine 1 stored in the rear of the main frame 1 is removed.
7' comes out immediately after the main body frame 1, the jacks 9 and 10 are expanded, the key support 17b is attached, and all the bolts of the joint plate 18 are tightened to form a complete ring-shaped support 17.

Thereafter, the operating jack 16 is retracted to store the rock retaining plate 14 as shown by the two-dot chain line in FIG. 4, and the rock retaining jack 12 is contracted to remove the rock as shown in FIG. The holding frame 11 is lowered, and the jacks 9 and 10 are further retracted to remove the support 17.
Separate. Concrete 23 is then sprayed near the top of the excavated inner surface between the shoring 17 immediately behind the main body frame 1 and the previously installed shoring 17. still,
At this time, the shotcrete construction of the bottom of the inner surface of the excavation has been completed.

Next, the moving jack 7 is retracted, and the temporarily assembled shoring 17' in the rear part of the main body frame 1 is gripped by the shoring gripping tools 8 of the jacks 9, 10, and the above-mentioned work steps are repeated thereafter.

In addition, in the case of an excavator that can use both segments and steel shoring, the segment method can be achieved by replacing the attachments of the shoring installation device and the ground securing device and using both devices as a perfect circle holding device. Construction can be carried out at

[Effects of the Invention] As explained above, according to the tunnel excavating machine of the present invention, () shoring can be installed on the inner surface of the excavation immediately behind the main body frame without impeding the workability of the excavating machine.

() Since the ground securing device can secure the ground near the top of the excavated inner surface between the shorings before shotcrete construction, it is possible to prevent the ground between the shorings from loosening, falling rocks, and collapsing.

() When it is necessary to drive lock bolts to prevent collapse before shotcrete construction, this can be done safely and easily through lock bolt driving holes drilled in the rock retaining plate of the rock securing device.

() The installation work is easy because the auxiliary materials can be installed at the same time as the shoring.

It can produce excellent effects such as

[Brief explanation of drawings]

FIG. 1 is a cutaway side view showing the rear structure of the tunnel boring machine of the present invention, FIG. 2 is a view taken in the direction of the - arrow in FIG. 1, FIG. 5 is a side view of the main parts showing details of the mountain securing device, FIG. 5 is a plan view of FIG. 4, FIG. 6 is a side view showing the connected state of the shoring, FIG. In Figure 8, I to D are work process diagrams. 1 is the excavator main frame, 2 is the fixed frame,
3 is a support frame, 5 is a roller, 6 is a scaffold, 7 is a moving jack, 9 is a shoring installation jack, 10 is a shoring expansion jack, 11 is a soil holding frame,
12 is a rock retaining jack, 13 is a rock bolt driving hole, 14 is a rock retaining plate, 16 is a retaining jack, 17 is a support, 20 is an auxiliary material, 22 is a rock bolt, and 23 is concrete.

Claims (1)

[Claims] 1 A support frame is fixed to a fixed frame within the main body frame of the tunnel excavation machine so as to protrude to the rear of the main body frame, and on the support frame is a scaffold that can be moved back and forth by a moving jack installed on the fixed frame. and a rock-holding jack, an arc-shaped rock-holding frame supported by the rock-holding jack, and a rock-holding frame rotatably attached to the rock-holding frame and having lock bolt driving holes drilled therein. A tunnel excavation machine characterized in that a ground holding device made of a plate, a shoring installation device made of a shoring jack, and a shoring gripping tool supported by the shoring jack are mounted on the scaffold.