JP2541743B2 - Concrete placing device for tunnel lining - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a concrete lining device for tunnel lining that prevents the already poured concrete from flowing backward when, for example, assembling reinforcing bars and placing concrete.

[0002]

2. Description of the Related Art In recent years, a so-called direct-cast concrete lining method has been widely used in shield tunnels. This direct-cast concrete lining method is
It is known as a construction method for speedy construction and labor saving, and without constructing an expensive and troublesome segment to assemble, at the same time as excavating the shield excavator, assemble the inner formwork at the tail part of the excavator, You can directly place lining concrete,
For this reason, there is an advantage that the lining concrete can be quickly installed and that water stoppage and structural weakness can be eliminated since no joints are generated. In addition, a pressure plate that plays the role of a gable form is pushed out to the tail void side with a pressure jack, etc., and a portion of the fresh concrete in the form is pressed to promote it while filling it with the ground, so backfilling is possible. There is also an advantage that injection or the like is not required. By the way, when the cast concrete is unreinforced, unlike the above segment, the concrete ring cannot bear the tensile force. Therefore, it is often a reinforced concrete structure having a primary lining concrete as a structure. At this time, in order to speed up the construction, a plurality of arc-shaped reinforcing bar cages assembled in advance in a cage shape are arranged on the outer periphery of the inner mold and held at a predetermined position by a metal object or the like, and then concrete placing is performed.

When the concrete is placed,
The propelling jack moves the excavator forward, and the pressure jack pushes backward the unhardened concrete to fill the tail void generated behind the excavator. The pressure plate of this pressure jack is returned to the position used in the next step by retracting the rod. In order to be able to continuously carry out the direct-cast concrete lining method of this reinforced concrete structure, the applicant of the present application previously has a shield mechanism for blocking the lining concrete immediately after placing it so as not to leak, As for the shield mechanism, we proposed a concrete lining device for tunnel lining that allows the lining concrete to be placed at the rear end of the tunnel while passing through the rebar unit incorporated on the face side (Japanese Patent Application No. 3). -32064).

[0004]

The above concrete placing device for tunnel lining has a center between an outer ring beam arranged inside a skin plate of an excavator and an inner ring beam arranged on the outer periphery of an inner formwork. By arranging the ring beam, the flexible elastic gates provided on the outer partition member of the outer ring beam and the inner partition member of the inner ring beam are spread by the ring rebar of the rebar cage through the center ring beam and the jack device. The assembling work of the reinforcing bar and the concrete placing work are continuously performed while preventing the inflow of the already placed concrete. However, in the above concrete placing device for tunnel lining, when the ring reinforcement of the reinforcing cage passes through the flexible elastic gate, the flexible elastic gate is in an open state, and the placed concrete passes through the gate. There was room for improvement in that a special jacking device was required to leak out or to push open the flexible elastic gate by the ring reinforcing bar of the reinforcing cage.

The present invention has been made in view of the above points, and is a shield formed by a concrete blocking member provided on a circumferential reinforcing bar of a reinforcing bar unit and an inner / outer ring assembly integrated with the already cast concrete. Due to
It is an object of the present invention to provide a concrete lining device for tunnel lining in which a rebar assembling work and a concrete placing work are continuously performed and the structure of the entire device is simplified.

[0006]

A concrete placing apparatus for tunnel lining according to the present invention has a cylindrical skin plate having a rotary cutter for tunnel excavation at a tip portion thereof and forming an outer shell of a main body behind the cutter. Incorporate an inner formwork that forms the peripheral wall of the tunnel inside the tail part of this skin plate, and arrange a rebar unit consisting of vertical rebar and ring rebar in the space between this inner formwork and the skin plate. In a concrete lining device for tunnel lining, in which concrete for tunnel lining is sequentially cast, and the cast concrete is pushed backward, an outer ring beam inscribed in the skin plate and an outer ring inscribed in the inner formwork. And an inner ring beam for rotating the rebar unit, and the rebar unit is inserted between the outer ring beam and the inner ring beam. And concreting the supporting mechanism to form a cylindrical space which is closed by at least one of the concrete shielding member attached to the ring rebar,
A concrete placing pipe that extends through the outer ring beam or the inner ring beam and is slidable in the tunnel axial direction; and a plurality of pressure jacks that slide the outer ring beam and the inner ring beam in the tunnel axial direction. It is characterized by having.

[0007]

According to the concrete placing apparatus for tunnel lining of the present invention, the outer ring beam is in close contact with the inner peripheral surface of the skin plate, the inner ring beam is in close contact with the outer peripheral surface of the inner mold, and the outer ring is further in contact. Since the space between the beam and the inner ring beam is closed by at least one concrete shielding member attached to the ring reinforcing bar, the placed concrete leaks through the shielding member of the ring reinforcing bar to the built-in space of the reinforcing bar unit. Can be prevented.

More specifically, the outer ring beam and the inner ring beam slide forward as concrete is poured, but the inner peripheral surface of the outer ring beam and the outer peripheral surface of the inner ring beam have a predetermined axial direction. It has a width (width wider than the installation interval of the shield member of the ring reinforcement),
Thereby, at least one shield member shields the cylindrical space of the outer ring beam and the inner ring beam.
Since this sealing structure is maintained regardless of the positions of the outer and inner ring beams, the poured concrete does not leak when the outer and inner ring beams pass through the ring rebar.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a concrete lining device for tunnel lining according to the present invention will be described below with reference to the drawings.

In FIG. 1, reference numeral 1 is a shield excavator 1
The outer shell of the shield excavator 1 is composed of a skin plate 2 and a front body portion 4 having a cutter 3. The cutter 3 has a disk shape, rotates to excavate the ground, and a blade (not shown) is provided on the front surface of the cutter 3. The skin plate 2 has a cylindrical shape, and the tail portion inside the skin plate 2 has a cylindrical inner formwork 5
The tip of is stuck in. The inner formwork 5 is configured by assembling, for example, five arcuately divided formwork and one key formwork by the erector device 60.

On the other hand, a propulsion pedestal 7 for supporting the propulsion jack 6 is formed on a portion of the inner surface of the front body portion 4 behind the cutter 3, and the propulsion pedestal 7 is pivotally attached to the propulsion pedestal 7. The propulsion pressure plate 9 provided at the tip of the rod 8 of the propulsion jack 6 contacts the end surface of the inner formwork 5. The propulsion jack 6 propels the shield excavator 1 forward as the face of the cutter 3 is excavated. The propulsion stroke of the propulsion jack 6 is set to such a length that the inner formwork 5 can be built therein. In addition, the concrete pouring support mechanism 1 is attached to the support portion 10 formed on the front body portion 4 side of the skin plate 2.
Pedestal 2 for concrete pouring support mechanism for supporting 1
0 is supported.

The concrete casting support mechanism 11 is connected to the inner ring beam 12, the outer ring beam 13, a holding member 14 for integrally connecting the inner ring beam 12 and the outer ring beam 13, and the holding member 14. The holding member 14 is formed of a holding pipe 16 holding the inner ring beam 12 and a holding plate 17 holding the outer ring beam 13. As shown in FIG. 2, the outer ring beam 13 is formed of an inner tube beam 18 and an outer tube beam 19 slidably attached to the inner tube beam 18 in the radial direction. An actuator (not shown) provided inside 18 moves in the radial direction. That is,
The outer cylinder beam 19 is set so as to follow the eccentricity of the shield excavator 1.

The outer peripheral surface of the inner ring beam 12 and the inner peripheral surface of the outer ring beam 13 form a cylindrical space therebetween. This cylindrical space has a predetermined width in the axial direction of the tunnel. This structure will be described later.

A plurality of pressure jacks 15 shown in FIG. 1 are arranged at equal intervals in the circumferential direction.
Has a base end portion swingably attached to a concave portion 20a provided in the pedestal 20 for concrete placing support mechanism, and the pressure jack 1
This allows the holding member 14 connected to 5 to move in the radial direction. Further, the expansion / contraction means 21 provided coaxially with the pressure jack 15 extends through the holding member 14, and the holding plate 21 a provided at the tip end portion is arranged between the inner ring beam 12 and the outer ring beam 13. Rebar unit 2
Abut 2.

As shown in FIG. 2, the reinforcing bar unit 22 includes longitudinal reinforcing bars 23 and ring reinforcing bars 24 for connecting the longitudinal reinforcing bars 23 to each other at positions spaced in the longitudinal direction.
And a reinforcing bar fixing member 25 for binding the longitudinal reinforcing bar 23 and the ring reinforcing bar 24, and each ring reinforcing bar 24 has a shield plate 26.
Is provided. As shown in FIG. 5, the reinforcing bar fixing bracket 25 has a vertical reinforcing bar fixing part 27 and a ring reinforcing bar fixing part 28. The vertical reinforcing bar 23 is inserted into the vertical reinforcing bar fixing part 27 and fixed by screws 29 to form a ring. By inserting the reinforcing bars 24 into the ring reinforcing bar fixing portions 28 and fixing them with screws 30, the longitudinal reinforcing bars 23 and the ring reinforcing bars 24 are bound together. Then, a shielding plate 26 as shown in FIG. 6 is mounted between the longitudinal reinforcing bars 23 and the ring reinforcing bars 24 of the bound reinforcing bar car 22. As shown in FIG. 7, the shield plate 26 is formed in a circular arc shape with a mesh cloth or a thin iron plate.

As shown in FIG. 2, the shield plate 26 has an inner peripheral surface of the outer ring beam 13 or an inner surface of a cylindrical member extending along the inner peripheral surface, and an outer peripheral surface of the inner ring beam 12, or the outer peripheral surface thereof. The cylindrical members extending along the outer peripheral surface are in close contact with each other and close the cylindrical space between the outer ring beam 13 and the inner ring beam 12. Further, the shield plate 26 is provided with the outer ring beam 13 described above.
And the inner ring beam 12 are arranged at intervals smaller than the width of the cylindrical space formed in the tunnel axis direction.

As a result, the shielding plate 26 can prevent the poured concrete from leaking to the building side of the reinforcing bar unit 22.

On the other hand, the concrete placing pipe 31 for the inter-shielding plate formed of a steel pipe having a substantially U-shaped placing port is inserted through the holding member 14 of the concrete placing supporting mechanism 11 and, as shown in FIG. It extends to the ring beam 12. The pouring port 32 of the concrete pouring pipe 31 between the shielding plates is
It can be freely opened and closed by the setting port gate 33. The inter-shielding plate concrete casting pipe 31 is used for pouring concrete into the space between the adjacent shield plates 26.

The concrete placing pipe 31 for shielding plates is made detachable at its tip by a placing pipe fixing portion 34. This inter-shielding plate concrete placing pipe 31 supplies the fresh concrete between the shield plates 26,
A concrete carrier pipe (not shown) connected to a concrete supply source such as a concrete pump (not shown) behind the tunnel is slidably fitted and connected to the tip of the concrete carrier pipe.

Further, the tail concrete casting pipe 36
As shown in FIG. 3, the inner ring beam 12 is inserted to supply concrete to the tail portion opposite to the face of the inner ring beam 12, that is, the space between the inner formwork 5 and the ground.

The concrete pouring port 36a formed at the tip of the tail concrete pouring pipe 36 can be opened and closed by a pouring port gate (not shown) provided in a part of the inner ring beam 12.

The tail concrete casting pipe 36 is slidable in the tunnel axial direction by a not-shown sliding jack, and is also slidable relative to the inner ring beam 12.

The tail concrete casting pipe 36 is
It can be moved in the tunnel axial direction in synchronization with the expansion and contraction of the pressure jack 15, and at the time of concrete pouring, it is synchronized with the pressure jack 15 with the concrete pouring port 36a slightly protruding from the inner ring beam 12. While shrinking, the concrete is sequentially supplied into the space between the ground and the inner formwork 5. When the concrete is pressed, the pouring port 36a is housed in the inner ring beam 12 and is closed by the pouring port gate. Pressure jack 15 in this state
Can be extended to push backward the already cast concrete which has not solidified yet, and to fill the tail void generated between the ground and the ground.

Further, as shown in FIG. 1, a ring beam perfect circle holding mechanism 38 is arranged at a position adjacent to the outer ring beam 13 on the concrete placing support mechanism 11 side. The ring beam perfect circle retaining mechanism 38 is preferably four on the vertical line passing through the center and two on the horizontal line passing through the center.
And are arranged at intervals of 90 degrees in the circumferential direction. Further, the ring beam perfect circle holding mechanism 38 is a plurality of rows spaced apart in the axial direction of the outer ring beam 13.

Next, the operation will be described.

FIG. 8 shows a concrete casting pipe 3 for shielding plates.
1 and the state where the concrete pouring from the tail concrete pouring pipe 36 is completed.

In this case, the concrete pouring port 32 of the inter-shielding concrete pouring pipe 31 is closed by the pouring port gate 33, and the concrete pouring port 36a of the tail concrete pouring pipe 36 is the same as the sliding jack. It is housed in the inner ring beam 12 due to the degeneration. The concrete pouring port 36a is closed by spring means attached to the pouring port gate, and the concrete pouring support mechanism 11 is pressurized by the pressure jack 15. At this time, the placing concrete does not leak to the concrete placing support mechanism 11 side through the reinforcing rod unit 22 by the shield plate 26 provided on the reinforcing rod fixing metal fitting 25 of the reinforcing rod unit 22.

When one step of placing concrete shown in FIG. 8 is completed, a step of preparing for assembling the reinforcing bar unit shown in FIG. 9 is started. In the preparatory stage for assembling the reinforcing bar unit, the propulsion jack 6 retracts, and the pressure plate 9 provided on the rod 8 of the propulsion jack 6 also separates from the inner mold 5. The propulsion stroke of the propulsion jack 6 is long enough to build the inner formwork 5.
Next, the concrete placing pipe 31 for shielding plates is released by the concrete placing pipe fixing portion 34, and the tail portion concrete placing pipe 36 is separated by the jack for sliding to be removed.

After that, the space for assembling the reinforcing bar unit 22 is formed by retracting the reinforcing bar unit holding plate 21a by the expansion / contraction means 21. In this case, since the reinforcing bar unit 22 is divided into a plurality of pieces, the inner ring beam holding pipe 16 of the concrete placing support mechanism 11 does not hinder the assembly of the reinforcing bar unit 22.

When the preparation step for assembling the reinforcing bar unit in FIG. 9 is completed, the step for setting the inner formwork shown in FIG. 10 is started. At this stage, the new reinforcing bar unit 22 ′ is connected to the existing reinforcing bar unit 22, and the expansion / contraction means 21 is extended so that the holding plate 21 a provided at the tip of the expanding / contracting means 21 is connected to the new reinforcing bar unit 22.
’Abutting on the end of the pipe and placing concrete between pipes 3
1. Attach and fix the tail concrete casting pipes 36, respectively. After that, a new inner formwork 5'is assembled by the formwork assembly by the erector device 60, and the propulsion jack 6 is extended.
Completed concrete pouring and preparation for excavation.

FIG. 11 shows the concrete pouring stage. At this stage, the tail concrete pouring pipe 36 is extended into the unconsolidated concrete by the jack for sliding, and concrete pouring is started between the natural ground and the inner formwork 5, 5 '.

In synchronization with this, the pressure jack 15
As the shrinkage occurs, concrete is placed between the shielding plates 26 from the concrete placing pipe 31 for shielding plates.

FIG. 12 shows the concrete pouring and excavation stages. At this stage, at the same time as the concrete is filled in the concrete placing step of FIG. 11, the concrete placing support mechanism 11 is pressurized by the pressure jack 15,
Alternatively, a predetermined set pressure is maintained while retracting, the propulsion jack 6 is extended, the excavation of the front body portion 4 is followed, or the lining is individually constructed. The same steps are repeated thereafter.

[0034]

As is apparent from the above description, according to the present invention, the backflow of concrete is performed while maintaining the pressure of the concrete poured by the shield plate and the concrete placing support mechanism provided on the ring rebar of the rebar cage. Therefore, when laying the tunnel by placing fresh concrete in the ground under high water pressure, the pressure of the fresh concrete can be maintained, so there is no inflow of groundwater, and the concrete placing support mechanism 11 prevents By forming the accommodation space for the reinforced car unit, the reinforced car assembling work and the concrete placing work can be continuously performed.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing an embodiment of a concrete placing device for tunnel lining according to the present invention.

FIG. 2 is a view showing a main part of a concrete placing device for tunnel lining according to the present invention.

FIG. 3 is a view showing concrete pouring using a tail portion concrete pouring pipe.

FIG. 4 is a diagram showing concrete placing using a concrete placing pipe.

FIG. 5 is a perspective view of a reinforcing bar fixing bracket.

FIG. 6 is a view showing a state in which a shielding plate is attached to the reinforcing bar cage.

FIG. 7 is a diagram showing a shielding plate.

FIG. 8 is a diagram showing a first stage of a construction sequence by the concrete placing device according to the present invention.

FIG. 9 is a diagram showing a second stage of the construction sequence by the concrete placing device according to the present invention.

FIG. 10 is a diagram showing a third stage of the construction sequence by the concrete placing device according to the present invention.

FIG. 11 is a diagram showing a fourth step of the construction sequence by the concrete placing device according to the present invention.

FIG. 12 is a view showing the final stage of the construction sequence by the concrete placing device according to the present invention.

[Explanation of symbols]

 1 Shield excavator 2 Skin plate 5 Inner formwork 6 Propulsion jack 7 Propulsion pedestal 9 Pressure plate 11 Concrete placing support mechanism 12 Inner ring beam 13 Outer ring beam 15 Pressure jack 22 Reinforcing bar unit 24 Ring rebar 26 Shielding plate 31 Shielding Concrete placing pipe for board 36 Tail concrete placing pipe

Claims (1)

(57) [Claims] 1. A cylindrical skin plate having a rotary cutter for excavating a tunnel at a tip portion thereof and forming a shell of a main body behind the cutter, and forming a peripheral wall of the tunnel inside a tail portion of the skin plate. Incorporate an inner formwork into the space between the inner formwork and the skin plate, place a reinforcing bar unit consisting of longitudinal rebars and ring rebars, and pour the tunnel lining concrete one after another. In the concrete lining device for tunnel lining adapted to be pressed to, the outer ring beam and the inner ring have an outer ring beam inscribed in the skin plate and an inner ring beam circumscribed in the inner formwork. At least one concrete shield that is inserted through the rebar unit between the beams and is attached to the ring rebar of the rebar unit A concrete pouring support mechanism forming a cylindrical space closed by a member, a concrete pouring pipe extending through the outer ring beam or the inner ring beam and slidable in the tunnel axial direction, the outer ring beam And a plurality of pressure jacks for sliding the inner ring beam in the axial direction of the tunnel, the concrete pouring device for tunnel lining.