JPS63165693A - Shield excavator - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of the Invention) The present invention relates to a shield excavation device, and particularly to a shield excavation device used for laying cables and the like under roads and the like.

(Prior Art) In the conventional shield excavation method using an ordinary shield excavator, only one type of diameter excavation and segment assembly can be performed.

(Object of the Invention) An object of the present invention is to provide a shield excavation device capable of excavating two or more diameters larger than the shield outer diameter and assembling segments.

(Structure of the Invention) In order to achieve the above object, according to the present invention, a cutter head of a shield excavator is provided with a radially movable overcutter, which cuts the tail portion of the shield excavator body, and further has a cutting edge at the tip. A circular outer cylinder having a diameter larger than the outer diameter of the shield may be fixed to the shield excavator main body so as to surround it.

(Example) Hereinafter, the present invention will be described in detail with reference to the drawings with regard to an example.

A shield excavation apparatus according to the present invention using a conventional shield excavator is shown in FIG. 1 is an ordinary shield excavator, which has a cutter head 2, a shield main body 3, an excavated soil intake device 4, a shield jack 5, and an erector 6 for assembling segments, and a tail portion 7 shown by an imaginary line is used for cutting. has been removed. This shield excavator has
According to the present invention, an overcutter 8 that is longer than usual is attached to the outer periphery of the shield body 3 so as to be movable in the radial direction. Furthermore, according to the present invention, the circular outer cylinder 9 having a cutting edge at the tip and having a diameter larger than the outer diameter of the shield is provided on the shield main body 3.
It is attached to a protrusion 10 on the outer periphery of the shield body 3 with bolts so as to surround the shield body 3.

Furthermore, a ring-shaped jack pressure transmission member 12 is arranged between the shield jack 5 and the reaction wall 11 at the rear of the shield body 3. Instead of the jack pressure transmission member 12, a new jack 12a is installed on the outer cylinder 9 as shown in FIG.
can be installed. When using the cast-in-place lining 11, the erector 6 is not used and the inner formwork 21 is attached to the jack pressure transmitting member 12, as shown in FIG.

When using the segment 17, extend the arm part of the erector as shown in Figure 2, and insert the segment 17 into the outer cylinder 9.
be able to be installed in In addition, if necessary, the outer cylinder 9
This can be done by attaching the reinforcing material 13 to.

Using the shield excavation apparatus of the present invention configured as described above, a vertical shaft will be constructed and horizontal excavation will be carried out in order to lay a cable or the like under a road, for example. A case will be described in which, for example, segments are used to construct a shaft.

First, the ground where the shaft is to be constructed is laid with a floor, and the shield excavation device according to the present invention shown in FIG. 2 is installed (FIG. 3). Next, while rotating the cutter head 2, the outer cylinder 9 and the shield excavator 1 are moved by the weight of the entire shield excavator.
dig together.

If it does not sink due to its own weight, for example, insert anti-14
A reaction force for the shield jack is taken through the horizontal member 15 and the vertical member 16, and the shield jack 5 is operated while the cutter head 2 is rotated to dig. In this way, when the rear end of the outer cylinder 9 comes close to the ground surface, the segment 17 is assembled into the tail part of the outer cylinder 9 on the jack 12a attached to the outer cylinder 9, and the cross member 15, Excavation is carried out by operating the shield jack 12a by taking a reaction force to the shaft 14 or the segment 17 through the vertical member 16 (Figs. 4 and 5).
figure). At this time, the outer diameter of the segment 17 is slightly smaller than the inner diameter of the outer cylinder 9, and in addition, after the outer cylinder 9 sinks, a gap corresponding to the thickness of the outer cylinder remains. The void 18 on the outer periphery of the outer cylinder 9 is immediately filled by backfilling with mortar or pea gravel.

Repeat this operation and when the predetermined depth is reached, retract the over cutter 8 of the cutter head 2, remove the bolt on the protrusion 10 of the shield body 3, and pull up the shield body 3 from the outer cylinder 9 (Fig. 6). . Face (bottom of shaft)
If there is a possibility of upheaval, the ground 19 should be improved in advance. Then, a bottom slab concrete 20 is placed in the space above the bottom of the pit surrounded by the cutting edge 9a of the outer cylinder 9, and the shield body 3 is suspended from the ground above it and installed horizontally (see Figures 7 and 7). Figure 8). A reaction wall 21 is placed behind the shield body 3, and a temporary support 22 is installed between the reaction wall 21 and the shield jack 5 of the shield body 3 (FIGS. 9 and 10). The outer cylinder 9 of the starting part is hollowed out to the thickness of the shield body 3, and while the canter head 2 is rotated, the shield body 3 is advanced by the shield jack 5 to start digging. Once there is a space for attaching the tail 7, attach the tail 7 to the rear end of the shield body 3 (Figures 11 and 12). Then, the shield body is excavated while installing the temporary shoring 22, and when the position where the segments 17 can be assembled is reached, the erector
6 to assemble the segments 17 while digging the shield main body 3 in the usual manner.

As shown in FIG. 13, for example, when horizontally excavating shields with different diameters from shaft 31 to shaft 32, the shield excavation device according to the present invention excavates between section A to excavate a large diameter horizontal hole. , then remove the bolts connecting the outer cylinder 9 and the shield body 3, and connect the shield body 3 between section B.
It is possible to dig further. The reaction force at the time of starting in section B is transmitted to the outer segments via the jerk transmission member 12.

Excavation can be performed by the method of the present invention regardless of whether the main body excavation device is a mud water pressure type or an earth pressure type.

When using a pressurized mud water system, the mud is sent through pipes by a drainage pump to a plant on the ground, where it is treated. In addition, even in the case of the earth pressure type, the excavated soil intake device 4
By shortening the length and installing equipment such as a tray lifter, it can be transported to the ground.

In addition, when the load on the overcutter is large (or when excavation is difficult or difficult, water jets are injected from the cutting edge of the outer cylinder 9 or the overcutter toward the cutting surface to cut, stir, and turn the soil into mud in advance). It is better to use auxiliary construction methods.

Furthermore, if the other mountain through which the shield passes is unstable due to water aquifer properties, an installation hole can be provided to connect the inside and outside of the outer cylinder 9 so that an underground drainage method (well point method) can be used in combination.

Also, instead of using reaction piles at the beginning of shaft excavation, anchors can be taken from the upper segment. The magnitude of the reaction force is determined by the weight of the shield itself, so no great force is required when digging horizontally.

(Effects of the Invention) In the shield excavation device of the present invention, an overcutter is provided on the cutter head of the existing shield excavator for horizontal excavation so as to be movable in the radial direction, and the tail portion of the shield body is cut, and the tip portion is A rectangular or circular outer cylinder with a cutting edge and a diameter larger than the outer diameter of the shield is fixed to the shield body so as to surround it. It can be used not only for horizontal excavation but also for making vertical shafts. As a result, construction costs can be significantly reduced. Further, the outer cylinder provided on the outside of the shield main body can be buried as it is after excavation is completed and used as a retainer. In addition, when excavating vertically, the shield itself used in the device of the present invention is heavy, so even if the outer diameter of the shield, that is, the outer diameter of the outer cylinder, becomes larger, the load on the shield jack and jack pressure transmission member will not be large. It has the advantage of not costing anything. Furthermore, since the device of the present invention starts horizontally with the tail portion of the shield excavator main body cut off, it has the advantage that the required circular shaft cross section is smaller than that of a conventional shield excavator with a tail portion. Furthermore, when the shield excavation device of the present invention is used, the excavation speed is faster than that of the unmanned circular caisson construction method, and the process can be significantly shortened.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view of a shield excavation device according to the present invention that uses a jack pressure transmission member without using an erector, and Fig. 2 shows a shield of the present invention that uses an erector without using a jack pressure transmission member. 3 to 6 are longitudinal sectional views of the excavation device, and FIGS. 3 to 6 are longitudinal sectional views showing the work process of constructing a shaft using the device of the present invention. FIGS. 7 to 12 are vertical sectional views of a conventional shield excavation machine. FIG. 8 is a view seen from the direction of arrow E in FIG. 7, FIG. 10 is a view seen from the direction of arrow F in FIG. 9, and FIG.
2 is a view seen from the direction of arrow G in FIG. 11, and FIG. 13 is an explanatory view when horizontally excavating shields having different diameters using the apparatus of the present invention. 1... Shield excavator 2... Cutter head 4... Excavated soil intake device 5... Shield jack 6... Erector 7... Tail portion 8... Over cutter 9... Outer cylinder 9a...Blade edge 11.17...Reaction wall 12...Jack pressure transmission member 13...Reinforcement material

Claims (1)

[Claims] (1) The cutter head of the shield excavator is equipped with a radially movable overcutter, which cuts the tail of the shield excavator body, and has a cutting edge at the tip and a circular outer cutter with a diameter larger than the outer diameter of the shield. A shield excavation device characterized in that a cylinder is fixed to a shield excavator main body so as to surround the tube, so that it is possible to excavate and construct a hole larger than the outer diameter of the shield excavator.