JP2501073Y2 - Shield machine's wife frame device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a gable frame device in a shield machine with a cast-in-place lining method.

[Conventional technology]

In the conventional lining method using a shield machine, the rebar and the inner formwork are assembled in the tail after the excavation is completed, the concrete is placed between the inner and outer formworks by using the tail plate as the outer formwork, and then the wife moves forward and backward with a jack. There is known a method of propelling a shield machine while transmitting motive force by pressurizing uncured concrete with a high pressure by a press ring that also serves as a formwork. But,
In this method, the thrust is transmitted to the concrete through the press ring, so that the concrete is biased and the quality thereof is impaired.

Therefore, a cast-in-place lining method disclosed in Japanese Patent Laid-Open No. 63-206598 is proposed as shown in FIG. That is, the expander / contractor 34 that expands from the contracted state toward the rear of the shield main body by the pressure fluid supplied through the suction / exhaust pipe 33 is provided on the outer periphery of the front end of the lining form 32 provided behind the rear end of the shield main body 31. Provided, the expansion body 34 is gradually expanded in accordance with the excavation by the shield machine, the pressure fluid is appropriately discharged in a predetermined expansion state to adjust the expansion pressure, and the expansion hole 34 is provided behind the expansion body 34 via the injection hole 35. By filling with concrete, the concrete 37 can be safely placed while supporting the natural ground 36 by the expansion / contraction body 34.

[Problems to be solved by the device]

In the conventional example described above, a large amount of expansion / contraction of the expansion / contraction body 34 is required,
There is a possibility that the bellows-like expansion and contraction part may be clogged with concrete 37.
Since it is in contact with 36, the tail voids cannot be sufficiently filled with concrete, which may cause loosening of the ground 36. In addition, there is a drawback that the expandable and contractible body 34 is easily damaged.

On the other hand, in a general gable frame concrete pressurizing device disclosed in, for example, Japanese Patent Application Laid-Open No. 1-299998, a plurality of gable frame pressure jacks are provided in the circumferential direction, and pressure is applied by the gable frame. Since this method is performed, it is difficult to uniformly press the entire circumference. Since the amount of pressure (stroke) at each position in the circumferential direction changes, an unreasonable force acts on the end frame, and the jack control for adjusting the concrete pressure becomes complicated, resulting in poor reliability. There are drawbacks.

Further, in the cast-in-place lining method in which the concrete is replenished during the excavation and is filled in the tail void, since the concrete is pumped by the concrete pump,
The concrete pressure in the placing space fluctuates due to the pulsation of the pump or the fluctuation of the shield excavation speed, etc., and a state in which it is not balanced with the external pressure of groundwater or earth pressure occurs. Therefore, as disclosed in JP-A-60-184199 and JP-A-63-181894, a mechanism in which the end frame device is equipped with an accumulator or a press ring device is required. However, in this case, a large number of devices, such as a gable frame pressure jack, are required and the outer periphery of the shield machine is mounted in a congested state with the propulsion jack, so the work space inside the shield machine is narrowed and the workability is reduced. There is an inconvenience of inviting.

[Means for solving the problem]

The gist of the present invention for solving the above-mentioned problems is a gable frame device in a shield machine with a cast-in-place lining method, wherein the gable frame device is a gland frame holding ring that is pressed against an inner formwork and the gable frame. A shield machine equipped with a gable frame pressure plate attached to a holding ring and sliding back and forth, and an air bag connected to an air supply line mounted on the back surface of the grate frame pressure plate. It is in the wife frame device.

[Action]

During excavation, a certain pressure is accumulated in the air bag through the air supply line, the end plate pressure plate is operated, and the pressure of the poured concrete filled following the occurrence of tail void is changed to earth pressure and water pressure. It can act in equilibrium. When the discharge amount of a concrete pump and the amount of tail voids generated by shield excavation do not match,
Since the tail void of the ground is not constant depending on the soil quality and the excavation result, there may be a volume change or pressure change that cannot be resolved even if the discharge rate and the excavation speed match, but for example, concrete pulsation based on the characteristics of a concrete pump When the pressure in the placing space fluctuates, the pressure in the concrete placing space is kept within a certain range by moving the end frame pressing plate in a predetermined direction by the pressure accumulated in the airbag, and the pressure in the tail void is always constant. Pressure can be applied, and it works to prevent soil and groundwater and groundwater from entering the lining concrete.

In addition, when the excavation is completed, the pressure of the airbag is increased through the air supply line, so that the lining concrete placed between the outer periphery of the inner formwork and the ground is further pressed through the gable frame pressing plate to further press the lining concrete. It promotes dehydration and acts to form a solid lining body.

〔Example〕

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is an enlarged vertical sectional view of a wife frame portion, FIG. 2 is a schematic vertical sectional view of an embodiment of a shield machine according to a cast-in-place lining method, and FIG. The right half is second
In the figure, a cross-sectional view taken along the line AA, and a left half view shows a cross-sectional view taken along the line BB.

As shown in FIG. 2, the shield machine has a skin plate (outer shell) 1 formed in a cylindrical shape.
A cutter head 2 is rotatably provided on the front surface of the device. Note that a shield machine having no cutter head may be used. An auxiliary tail 4 is concentrically provided inside the shield tail 3 at the rear part of the skin plate 1, and an elastic bag 5 is interposed between the shield tail 3 and the auxiliary tail 4. The elastic bag 5 is divided into an appropriate number in the circumferential direction (Fig. 3). Although not shown, the auxiliary tail 4 is connected to the shield machine side via a sliding jack and is configured to move with the propulsion of the shield machine.

An inner formwork 6 is installed on the inner surface of the concrete cast by the cast-in-place lining method, and the ring-shaped gable frame device 7 is provided so as to abut on the end face 6a on the face side of the inner formwork 6. There is. That is, the rod side of the gable frame jack 11 pivotally attached to the shield machine side is hinge-connected to the gable frame device 7, and when the gable frame device 7 moves in the propulsion direction of the shield machine and is removed from the gable frame. Except for the gable frame device 7,
It is pressed and fixed to the side surface.

As shown in FIG. 3, a plurality of propulsion jacks 13 are annularly arranged inside the shield machine. This propulsion jack 13 is a two-stage type telescopic jack. As shown in FIG. 2, the second stage rod 13B of the propulsion jack is inserted into the sheath pipe 15 through the end frame device 7, and the sheath pipe 15 The shield machine is dug by applying a reaction force to the composite shaft 17 formed of the super-hard mortar. Further, the gable frame jack 11 dedicated to the gable frame movement described above is also provided in the shield machine in a required number of annular shapes (FIG. 3). Since the gable frame jack 11 does not pressurize concrete, the number of arrangements can be small. In FIGS. 2 and 3, 16 is a reinforcing member (rebar cage), 18 is currently cast concrete, 19 is already cast concrete, 20 is concrete casting pipe, and 21 is natural ground.

As shown in the enlarged cross-sectional view of the end frame portion of FIG. 1, the end frame device 7 includes a end frame holding ring 8 and a end frame pressing plate 9 provided with an airbag 10. That is, a gable frame pressing plate 9 having a U-shaped cross section and an air bag 10 enclosed by the gland frame holding plate 9 are housed in the step portion of the gable frame holding ring 8. 8a is a liner fixed to the gable frame holding ring. As shown in FIG. 3, the airbag is divided in the circumferential direction so as to avoid the sheath pipe 15, the concrete casting pipe 20, and the like. This airbag
An air supply line is connected to 10, and a pressure regulating valve 12a is interposed to keep the pressure inside the airbag 10 constant. Air from the air supply source (not shown) is supplied to the air bag 10 through the air supply line 12 at a predetermined pressure so that the air bag 10 is inflated and the gable frame pressing plate 9 presses the concrete in the direction of the arrow. Slide on.

Thus, by accumulating a constant pressure in the airbag 10, the pressure of the poured concrete filled following the generation of the tail void during excavation can be balanced with the earth pressure and the water pressure. Further, when the excavation is completed, the pressure of the airbag 10 is increased to further press the poured concrete to accelerate dehydration of the excess water of the concrete, thereby achieving early strength development. A gable frame seal 14 is provided on the outer peripheral surface of the gable frame pressing plate 9 so as to slide against the inner surface of the auxiliary tail 4 to seal against the currently placed concrete 18.

FIGS. 4 (a) to 4 (f) are views showing the order of construction based on the cast-in-place lining method according to the present invention over time. That is, FIG. 4 (a) shows a situation in which the gable frame 7 is slid in the propelling direction by the gable frame jack 11 and the gable frame 7 is demolded after curing the lining concrete (already cast concrete) 19 constructed last time. Show. At this time, the telescopic jack 13 is contracted to take an insertion space for the reinforcing rod cage 16.

FIG. 4 (b) is a view showing a preparatory work for placing lining concrete. After removing the end frame 7, the rebar cage 16 with a sheath pipe is held by the second stage rod 13B of the telescopic jack 13, It is connected to the synthetic shaft 17 constructed last time, and the rebar cages 16 with sheath tubes divided into a plurality of parts are assembled by a binding wire or the like. Further, the inner mold frame 6 divided into a plurality of pieces like the sheathed steel cage 16 is assembled by an inner mold erector (not shown).

Fig. 4 (c) shows the gable frame 7 in the concrete placing space 18 '(the same figure (b)) surrounded by the lining concrete 19, the inner formwork 6 and the grate frame 7 constructed last time. The situation where fresh concrete is filled from a plurality of concrete placing pipes 20 arranged so as to penetrate therethrough is shown.

FIG. 4 (d) shows the synthetic shaft 17 (FIG. 4 (b)) formed in the lining concrete 19 constructed last time as a reaction force to extend the first stage rod 13A of the telescopic jack 13 and accordingly, A situation is shown in which shield digging is performed while the generated tail voids 22 are being filled (primary pressure of about 0.5 to ² kg / cm ² ) with fresh concrete fed by a concrete placing pipe 20 in synchronization with the amount of digging. In this case, the concrete pouring pipe 20 has its discharge port located in the vicinity of the end of the shield tail 3, and the tail void 22 is effectively filled with the fresh concrete following the excavation length.

The amount of tail voids generated by the movement of the shield tail is constant if the speed of movement of the shield machine and the state of the ground are constant, but the actual discharge rate of the concrete pump is constant because both the excavation speed and the ground state change. Even if kept at, the pressure of the poured concrete will fluctuate. However, since groundwater pressure and earth pressure of the ground always act on the poured concrete,
In order to form a good and watertight lining body, it is necessary to always maintain the pressure of the poured concrete above the external pressure of the ground. Therefore, in the present invention, the end frame pressing plate 9 built in the end frame holding ring 8 is pressed by the accumulated pressure of the airbag 10 to compensate for this. As a result, it is possible to avoid a situation in which the pressure of the poured concrete becomes equal to or lower than the external pressure, and the earth and sand and groundwater are mixed into the poured concrete and the quality of the lining concrete is deteriorated.

FIG. 4 (e) is a diagram showing the state of secondary pressurization of the lining concrete (currently placed concrete) 18 constructed this time after the completion of the excavation. As shown in FIG. 1, the air supply line 12
The air of a predetermined pressure is supplied to the air bag 10 through the air bag 10, the pressure of the end frame pressing plate 9 is pressed by the pressure of the air bag 10, and the concrete is pressed through the end frame pressing plate 9 (about 5 to 10 kg / Secondary pressurization of cm ² ). As a result, the lining concrete 18 of this construction, which is not yet solidified, is further pressurized and dehydrated to achieve early strength development and improve the self-supporting property and water stopping property of the concrete in the gable portion.

Fig. 4 (f) shows the situation in which a synthetic shaft that is the propulsive reaction force of the shield machine is formed within the time to cure the lining concrete 18 constructed this time. Injection tube for ultra-rapid hardening mortar inside the sheath tube 15 fixed to 16 by a mortar pump (not shown)
It is filled through 23 to make the synthetic shaft 17 constructed last time continuous.

[Effect of device]

As described above, according to the present invention, the following effects can be obtained. That is, (1) Even if the balance between the discharge rate of the concrete pump and the tail void generation rate is lost, the pressure of the poured concrete can be adjusted by the air bag, so that the pressure control that is always in balance with the earth pressure and water pressure of the natural ground can be performed. As a result, the amount of change in the amount of tail void in the natural ground, which cannot be captured as the set value, can be compensated by the accumulated pressure of the airbag, so that the mixing of earth and sand and groundwater does not occur and the quality of the lining concrete is not impaired. Even with the conventional method of moving the gable frame along the inner formwork, pressure control can be similarly performed by equipping the gable frame surface with the gable frame pressure plate with the airbag, and the same effect can be obtained. To be

(2) When an air fluid (compressible) pressure accumulator such as an air bag is used by itself, even if the control mechanism such as a complicated hydraulic device is not installed, Change can be suppressed.

(3) The structure of the airbag section can be easily configured. Then, by adjusting the pressure in the airbag, the concrete in the entire circumferential direction can be uniformly pressed, and if a pressure regulating valve is provided in the air supply circuit so as to keep the pressure in the airbag constant, the concrete can be The pressure in the casting space can be kept constant, which has the effect of not disturbing the ground. Further, since the pressing force is applied in a wide range on the back surface of the end frame pressing plate, an unreasonable force does not act on the end frame pressing plate. In addition, by increasing the air pressure, it is possible to re-pressurize the filled concrete, accelerate demolding of the gable frame, and improve work efficiency.

[Brief description of drawings]

1 to 4 are views for explaining the present invention.
FIG. 1 is an enlarged vertical sectional view of a gable frame portion of a shield machine, FIG.
The figure is a schematic vertical cross-sectional view of a cast-in-place shield excavator, FIG. 3 is a main part view of the end frame of the shield excavator, and the right half is a cross-sectional view taken along the line AA in FIG. The left half is a sectional view taken along the line BB, and FIGS. 4 (a) to 4 (f) are views showing the construction sequence of the cast-in-place lining method of the present invention over time. FIG. 5 is an explanatory diagram of a conventional technique. 3 ... Shield tail, 4 ... Auxiliary tail, 5 ... Elastic bag, 6 ... Inner form, 7 ... Wife frame (device), 8 ... Wife frame holding ring, 9 ... Wife frame pressure plate, 10 ... airbags,
11 …… Wife frame jack, 12 …… Air supply line, 12a ……
Pressure regulator, 13 …… Propulsion jack (telescopic jack), 15 …… Sheath pipe, 16 …… Reinforcement member (rebar cage), 17 ……
Synthetic shaft, 20 …… Concrete pouring pipe.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Toshitsugu Horizaki, 2nd Sanbancho, Chiyoda-ku, Tokyo, Tobishima Construction Co., Ltd. (72) Yoshikazu Inada 2nd Sanbancho, Chiyoda-ku, Tokyo, Tobishima Construction Co., Ltd. ( 72) Inventor Shuji Sakaguchi 8-21-1, Ginza, Chuo-ku, Tokyo Takenaka Civil Engineering Co., Ltd. (72) Hidetaka Omori 8-21-1, Ginza, Chuo-ku, Tokyo Incorporated Takenaka Civil Engineering (72) Masanobu Kanno 8-21-1, Ginza, Chuo-ku, Tokyo Takenaka Civil Engineering Co., Ltd. (72) Inventor Hiroshi Sakurai 8-21-1, Ginza, Chuo-ku, Tokyo Civil Engineering Co., Ltd. Takenaka (72) Revised by Kiyohide 3-1-1 Higashikawasaki-cho, Chuo-ku, Kobe-shi, Hyogo Inside Kawasaki Heavy Industries, Ltd.'s Kobe factory (72) Yoshimi Ishikawa 3-chome, Higashi-kawasaki-cho, Chuo-ku, Kobe-shi, Hyogo No. 1 No. 1 Kawasaki Heavy Industries, Ltd. Kobe Factory (56) Reference JP 63-134795 (JP, A) JP 1-203598 (JP, A)

Claims (1)

(57) [Scope of utility model registration request] 1. A gable frame device for a shield machine of cast-in-place lining method, wherein the gable frame device is attached to the grate frame holding ring that is pressed against the inner formwork and the gable frame holding ring. A gable frame device for a shield machine, comprising a gable frame pressure plate that slides on an end, and an airbag connected to an air supply line attached to the back surface of the gable frame pressure plate.