JPS5921891A - Intermediate folding type 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 The present invention relates to a center-folding type shield excavator that can easily perform curved excavation with a small radius of curvature.

Shield tunneling machines are widely used as the safest tunneling machines when constructing tunnels in soft ground, especially in water-logged sand and gravel layers, and are designed to apply a lining to the tunnel as the excavation progresses. has been done. This lining is assembled by axially abutting a series of sections consisting of a plurality of segments joined in a circular, semicircular, horseshoe, etc. shape.

By the way, when excavating urban tunnels for water supply, sewage, subway, power, and communication cables, curved excavation with a relatively small radius of curvature is required due to constraints such as location conditions. A so-called center-folding type shield excavator is used in which the rear shield is divided into two parts and these parts are connected in a bendable manner. Conventional folding type shield tunneling machines operate the shield jack on the outside of the curve to propel the front shield, and then operate the shield jack on the inside of the curve to pull the rear shield. , the reaction force of the shield jack when the front shield moves forward is captured in segments. Therefore, such a center-folding type shield tunneling machine is capable of making curves with a smaller radius of curvature than an integrated type shield tunneling machine, reducing the amount of excess excavation, and preventing the collapse of the ground. It has the great advantage of being able to reduce the amount of backfilling.

However, in this type of center-folding type shield excavator, when the front shield is advanced, the segment is used as a reaction force, so there is no problem, but when the rear shield is advanced, it is used as a fixed body. The front shield moved easily, making it difficult to control the direction of the rear shield.

Also, depending on the ground conditions in the construction section, the ground may stand on its own like a loam layer, or if the construction is carried out using shoring, etc.
Since segments were not required, the reaction force had to be obtained from something other than the segments.

The present invention has been made in view of the above-mentioned points, and provides a center-folding type shield that can reliably obtain a reaction force on a free-standing mountain, etc., and that allows the direction of the shield body to be easily and reliably controlled. The feature is that the brake plate is driven into the tunnel peripheral wall using a segment erector device in self-supporting ground, shoring areas, etc., and this brake plate is used to prevent the front shield from moving forward. When the rear shield was moved forward, the brake plate was removed from the tunnel peripheral wall and the shield jack was used to press the rear shield forward.

Hereinafter, the present invention will be described in detail based on embodiments shown in the drawings.

FIG. 1 is a longitudinal cross-sectional view showing an embodiment of a foldable shield tunneling machine according to the present invention, and FIG. 2 is a half cross-sectional view taken along the line ■--■ in FIG. In these figures, a folding type shield excavator 1 is equipped with a front shield 2 and a rear shield 3, each of which is a cylindrical body shaped like a #de and open at both ends.
These two shields 2.3 are normally bently connected by a suitable connecting rod (not shown) to constitute a center-folding type shield excavator main body. In this case, the small diameter portion 4 provided at the rear end of the front shield 2 is inserted into the inner circumferential surface of the front end of the rear shield 3 via the shield packing 5, and the above-mentioned connection connecting both shields 2 and 3 is inserted. The rods are removed when the shields 2, 3 are alternately moved forward (described later), thereby allowing the shields 2, 3 to move relative to each other.

At the center of the interior of the front shield 2, an excavator 10 with a cutter portion 10 projecting forward to excavate a face portion 12 on the front surface of the shield, and an operation room 11 for operating the excavator 10 are disposed. . The excavator 10 is configured to be rotated forward and backward in a diagonal shape around its rear end, and the cutter portion 10A is rotatably driven in a telescopic manner. The earth and sand excavated by the excavator 10 is conveyed rearward by a belt conveyor 13 disposed inside the shield excavator body and discharged to the outside of the tunnel 16. Also, when drilling the face portion 12 in front of the shield,
In the case of hard geology where the face 12 can stand on its own, excavation can be carried out without any problems, but in the case of soft ground where the face 12 collapses, not only will dirt flow into the shield, but the ground will subside. In order to prevent this, a movable hood jack 14. A half-moon jack 15 and the like are arranged on the ceiling surface of the front end of the front shield 2.

On the other hand, a well-known ring-shaped segment erector device 18 is disposed inside and rearward of the rear shield 3.

The segment erector device 18 is rotatably supported by a plurality of rows 219 arranged concentrically inside the rear shield 3, and includes an erector mailing ring 20 driven by a swing motor 1T. An erector 22 is disposed at 20 for assembling a lining 21 shown by chain lines as the tunnel is excavated.

The lining 21 has arc-shaped segments 21 m and 21 b made of iron, concrete, etc. divided into six parts, for example.

21e... are joined together in an annular shape, and each segment Han21b*21c... is suspended by the erector 22, and positioned at a predetermined position by the rotation of the erector ring 2o. After that, the inner circumference MK of the rear shield 3 is pressed and assembled. Then, the assembled lining sheets 21 are successively joined in series with a backfilling material such as mortar, and as the rear shield 3 moves forward, it is delivered into the tunnel from the rear end opening of the shield 3. A tail packing 25 is disposed around the entire circumference of the tail inner circumferential wall of the rear shield 3, and the outer circumferential surface of the lining sheet 21 slides thereon to prevent muddy water and the like from entering.

At the connecting portion between the front shield 2 and the rear shield 3, a plurality of shield jacks 27 are provided at predetermined intervals in the circumferential direction of the small diameter portion 4, each extending in the front-rear direction along the inner circumferential wall of the small diameter portion 4. are arranged in parallel with each other, and their respective jacks 2
The front end of the jack main body 27a of No. 7 is held and fixed to a mounting plate 28 provided on the inner peripheral wall of the front shield 2. On the other hand, a spreader shoe 30 is attached to the outer end surface of the rod 27b of each shield jack 27 via an eccentric fitting 29. Each shield jack 2T is connected to an appropriate hydraulic pressure supply source (not shown) and pressurized oil is supplied at a constant speed, thereby regulating the main body of the shield excavation machine using the lining jack 21 as a reaction force. It is configured to move forward at a speed. That is, each shield jack 2T is driven and its rod 27b extends rearward, and the spreader cable 30 is moved to the opposite segments 21m, 2.
1b.

When the front end surfaces of the shield jacks 21c are pressed at the same time, they receive a reaction force from the lining 21 of each shield jack 2T, and as a result, the front and rear shields 2 and 3 are moved forward as a unit. Therefore, at the mouth where the lining sheet 21 is pushed out relatively rearward and installed in the tunnel 16, the lining sheet 21 using such a segment method is effective and effective in constructing tunnels on soft ground as described above. Although this is the safest method and can prevent the collapse of the ground and water springs, it is self-supporting using a shoring method, etc., and no lining system 21 is carried out when excavating the ground. As shown in FIGS. 1 and 2, a plurality of brake plates 40 are used when the front shield 2 moves forward. 7- That is, these brake plates 40 are sequentially driven into the peripheral wall of the tunnel 16 by the aforementioned segment erector device 18 through circumferentially long slit-shaped insertion holes 41 provided in the peripheral wall of the rear shield 3. The shield 3 is temporarily fixed to the tunnel peripheral wall, and by being installed corresponding to each shield jack 21, it constitutes a reaction force for these jacks 27.

In this case, the forward movement of the self-supporting ground is achieved by moving the front shield 2 and rear shield 3 forward alternately by the reciprocating motion of the shield jack 2T, so that the above-mentioned connecting rod that connects both shields 2 and 3 is used. is removed, and in its place, the spreader shoe 30 of each shield jack 2γ is connected to the rear shield 3 by a wire or the like, and its tip end face closely faces the surface of each brake plate 40. Therefore, both shields 2 and 3 are connected by the shield jack 21, so that both shields 2 and 3 are connected by the shield jack 21.
Preparations for alternately moving 2.3 forward are completed.

8- When moving the front shield 2 and the rear shield 3 forward in such a state, first the brake plate 40 is driven into the peripheral wall of the tunnel 160 by the segment erector device 18 to fix the rear shield 3 to the tunnel 16. In this state, when all the shield jacks 2T are simultaneously driven to extend their rods 27b, the spreader shoe 30 presses the brake plate 4o. However, the brake plate 40 is driven into the tunnel peripheral wall and forms a reaction force, and as a result, the front shield 2 is moved forward by the stroke of the jack 2T.

The stroke of this shield jack 2T is for both shields 2
．． It is set shorter than the length of the connecting part M in No. 3.

Next, after the shield 2 moves forward by a predetermined distance and stops, all the brake plates 4o are pulled out from the tunnel peripheral wall by the segment erector device 18, and the rear shield 3 is released from the tunnel peripheral wall. After that, when all the shield shirts dF27 are driven and the fully extended rods 27b are pulled into the jack main body 27a, the rear shield 3 connected via the rod 27bK spreader shaft 30 is drawn toward the front shield 2 side. move forward. In this case, the weight of the front shield 2 is sufficiently large compared to the rear shield 3, so the rear shield 3
can definitely be attracted. By repeating these series of operations, the front and rear shields 2 and 3 alternately move forward, making it possible to excavate nine tunnels 16 in a self-supporting ground.

The number of brake plates 40 may vary depending on the condition of the ground.

By arbitrarily setting the length, oil pressure of the segment erector device 18, etc., it is easy to control the driving amount of the brake plate 4a and it is possible to obtain a predetermined reaction force.

In addition, the brake plate 40 has a simple structure, does not require any special hydraulic equipment, etc., and is removed when constructing a tunnel using the segment method. ) 2
Group 11 of 1ap21b*21e... will not cause any trouble to heavy work.

As explained above, the folding type shield excavator according to the present invention connects the front shield and the rear shield in a bendable and slidable manner, and drives a plurality of brake plates into the tunnel peripheral wall by driving the segment erector device. Temporarily fix the rear shield to the tunnel peripheral wall, use this brake plate as a reaction force of the shield jack to advance the front shield, and then pull out the brake plate from the tunnel peripheral wall.
Since the shield jack is configured to pull the rear shield forward, the direction control of each shield is easy and reliable, making it possible to construct tunnels with high precision.In addition, since both shields are moved forward alternately, The thrust of the shield jack can be set to a small value, and by removing the brake plate, it is easy to switch to the segment propulsion method, which is effective in tunnel construction where both the segment construction method and the shoring method are used in the construction section. and effective.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view showing an embodiment of a folding type shield excavator according to the present invention, and FIG. 2 is a half cross-sectional view taken along the line . 1...Central folding type shield excavator, 2...Skewer...front shield, 3...rear seed, 18...ee segment erector device, 27...shield jack, 4
0.-6.Brake plate, 41.....insertion hole. Patent Applicant Mitsui Engineering & Shipbuilding Co., Ltd. Agent Masaki Yamakawa (Iji Tame 1 person) 12-

Claims (1)

[Claims] It is bendable and is relatively slidably connected to the front shield and the rear shield when moving forward, and is located at the joint between the two shields, with one end held and fixed to the front shield and the other end selectively attached to the rear shield. a shield jack connected to the rear shield; a segment erector device rotatably disposed within the rear shield for assembling the segments; A center-folding type shield excavator comprising a brake plate driven into a tunnel peripheral wall by an erector device and constituting a reaction force body of the shield jack.