JP3481532B2 - Form lifting control method and apparatus - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for controlling a form up and down when installing a form in a process of installing a form in a tunnel and placing concrete for lining. In the present specification, "casting" means filling mud-like concrete that has not been cured by curing between the formwork and the inner wall surface of the tunnel.

[0002]

2. Description of the Related Art Originally, when placing concrete for lining in a tunnel, a formwork for placing concrete was used.
After the concrete was placed, it was folded and conveyed forward, unfolded and installed, and concrete was placed at that location by a movable formwork.

When installing this formwork, after unfolding the formwork in a pre-folded state, the lap side (tunnel pit side) of the formwork is polymerized with the existing concrete pouring surface, and the gable side of the formwork ( The tunnel face) is a gable frame to prevent the concrete filling between the formwork and the inner wall of the tunnel from leaking to the outside.
It was covered with a covering material such as a gable board.

In the overlapping work between the lap side of the formwork and the existing concrete pouring surface, the formwork is raised by an operator visually through an elevating mechanism so that the lap side of the formwork contacts the existing concrete pouring surface. This was done by contact (see FIG. 4).

In the figure, 12 is a tunnel, 16 is a form,
Reference numeral 18 is an elevating mechanism, 30 is an existing concrete placing surface, 32 is an inner wall surface of a tunnel, and 36 is a crack (crack).

[0006]

Conventionally, when the lap side of the formwork is overlapped with the existing concrete placing surface when the formwork is installed,
Since the operator visually observed through the formwork lifting mechanism, the lap side of the formwork easily accidentally collided with the existing concrete pouring surface, and the collision of this formwork caused cracks (cracks) on the existing concrete pouring surface. ) Was generated, which was a cause of deterioration of quality of the cast concrete that had been lined (cured and hardened), and deterioration of tunnel strength (see FIG. 4).

In view of the above drawbacks, the present invention provides a method and apparatus for controlling the raising and lowering of a mold, which can control the rise of the mold during installation of the mold and prevent a collision with an existing concrete placing surface. The purpose is to do.

[0008]

According to the present invention, in the step of placing a formwork in a tunnel and placing concrete for lining, the present invention is provided so as to project freely on the lap-side outer peripheral side edge of the formwork. By detecting the contact of the detection bar to the existing concrete placing surface, after stopping the rising of the formwork elevating mechanism at the time of installing the formwork before the position of contacting the existing concrete placing surface,
By slowly ascending and contacting the formwork with the existing concrete pouring surface, the occurrence of cracks due to the collision of the formwork with the existing concrete pouring surface is prevented.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The formwork lifting control device according to the present invention is mounted on a movable formwork 16 for placing concrete 14 for lining in a tunnel 12.
As shown in FIGS. 1 to 3, it has the following configuration.

In this example, the formwork 16 comprises a lifting mechanism 18
The top plate foam 22 and the side foam (not shown) are mounted on the gantry 20 having the lifting jack.

A detection bar 24 is provided on the outer peripheral edge of the form 16 on the lap side (tunnel pit side) so as to be retractable.

In the present example, the detection bar 24 is a mold 16
At the outer peripheral edge of the top plate foam 22 on the lap side, it is freely retractable by being urged to protrude outward through the elastic body 26, and when coming into contact with an already-concrete concrete placing surface 30 described later. The detection bar 24 is buried against the elastic force of the elastic body 26, and when the detection bar 24 is buried for a predetermined length or more, the limit switch 28 is actuated and the elevating mechanism 18 of the mold 16 is stopped. There is.

The elevating mechanism 18 is controlled so that the mold 16 stops about 5 mm before the existing concrete placing surface 30.

Further, the detection bars 24 are arranged at equal intervals in the circumferential direction of the outer peripheral edge of the top plate foam 22 forming the mold 16.
It is desirable to mold with a synthetic resin material so as not to damage the existing concrete placing surface 30 because it is arranged individually and comes into contact with the existing concrete placing surface 30.

In the figure, reference numeral 30 designates concrete 1 for lining.
Reference numeral 4 denotes an already-cast concrete placing surface that has been placed and lined (cured and hardened), 32 is an inner wall surface of the tunnel, and 34 is a limit lever.

A method of placing concrete 14 for lining in the tunnel 12 using this apparatus will be described in detail below.

First, a pre-folded formwork 16 is positioned at a concrete pouring place in the tunnel 12.

Next, the form 16 is developed.

Next, the mold 16 is raised by the elevating mechanism 18.

Next, as the mold frame 16 rises, the detection bar 24 is projected and retracted to the outer peripheral edge of the mold frame 16 on the lap side.
Contact the existing concrete pouring surface 30.

By contacting the existing bar 30 with the detection bar 24, the detection bar 24 is buried for a predetermined length or longer, and then the limit switch 28 is operated to stop the elevating mechanism 18 and raise the formwork 16. Stops.

At this time, the formwork 16 is stopped before the existing concrete placing surface 30.

Further, since a plurality of detection bars 24 are arranged at equal intervals in the circumferential direction of the top plate foam 22 constituting the form 16, the detection bar 24 is provided on the existing concrete placing surface 30 of the ceiling of the tunnel 12. Not limited to this, the contact of the formwork 16 with the existing concrete placing surfaces 30 on both sides of the tunnel 12 is also detected.

Therefore, when the formwork 16 is lifted up, the existing concrete pouring surface 3 on the ceiling and both sides in the tunnel 12 is lifted.
The collision to 0 is reliably prevented, and the tunnel 12 of the formwork 16
It is possible to control the installation position in the vertical direction and the horizontal direction with respect to.

Next, the elevating mechanism 18 is actuated by visual inspection of the operator or through a sensor (not shown) to form the mold 1
6 is slowly raised to the existing concrete placing surface 30 side, and the lap side of the form 16 is gently brought into contact with the existing concrete placing surface 30.

Next, the gable side of the formwork 16 (tunnel face side)
Is covered (sheathed) with a covering material (not shown) such as a gable frame, gable plate, etc., and the concrete 14 is introduced from a predetermined inspection window (not shown) of the formwork 16 between the formwork 16 and the tunnel inner wall surface 32. To set.

At this time, according to the concrete pouring amount, the pouring concrete is vibrated via a vibrating tool (not shown),
It is desirable to improve the strength and durability of concrete after curing and hardening by compacting.

Next, after the operation of placing a predetermined amount of concrete 14 is completed, the concrete 14 is poured from another inspection window (not shown).
Then, the concrete 14 is cast on the entire area between the formwork 16 and the tunnel inner wall surface 32.

Next, after the casting concrete is cured and cured, the covering on the end side of the mold 16 is released, and then the mold 1
Demold 6

After that, the mold 16 is moved forward, the mold 16 is installed, the mold side of the mold 16 is covered, concrete is poured, the mold 16 is released from the mold, and the steps are sequentially carried out.

As described above, the form lifting control device and method according to the present invention prevent the lap side of the form 16 from accidentally colliding with the existing concrete placing surface 30 when the form 16 is installed. Cracks (see reference numeral 36 in FIG. 4) on the existing concrete placing surface 30 due to the collision of the frame 16 are completely eliminated, so that the quality of the lining (cured and hardened) placed concrete is improved, and the tunnel strength is increased. And the durability of the tunnel can also be improved.

In this example, the number of the detection bars 24 protruding to the outer peripheral side edge of the wrap side of the mold 16 is eight, but the number is not particularly limited, and the wrap of the mold 16 is not limited. It is desirable that the number is such that it is easy to detect that the side comes into contact with the existing concrete placing surface 30.

The detection bar 24 has an elastic body 26 inside.
It can be freely retracted by urging it to project outward through
The detection bar 24 is configured to be buried against the elastic force of the elastic body 26 when it comes into contact with the existing concrete placing surface 30, but it is not limited to being capable of retracting through the elastic body 26. However, it is free to adopt other retractable structures.

The stop of the elevating mechanism 18 of the mold 16 is
The limit switch 28 is actuated by burying the detection bar 24 for a predetermined length or more to stop the elevating mechanism 18, but the limit switch 28 is not limited to the lever type and may be the capacitance type. Also, it is free to adopt sensors and other mechanisms.

Concrete pouring between the formwork 16 and the tunnel inner wall surface 32 is performed through the inspection window. The concrete pouring port formed on the formwork 16 separately from the inspection window. It is obvious that concrete is added using (not shown).

It is also obvious that the method and apparatus of the present invention can be applied not only to the use in a substantially semi-circular tunnel but also to a circular tunnel such as an undersea tunnel or a sewer tunnel.

[0037]

According to the method and apparatus for controlling the raising and lowering of the formwork according to the present invention, the detection of the contact of the detection sensor projecting so that the outer peripheral side edge of the formwork can project and retract with the existing concrete placement surface can be detected. To stop the raising of the formwork by the elevating mechanism when installing the formwork before the position where it comes into contact with the existing concrete pouring surface, and then slowly ascend the formwork to the existing concrete pouring surface. , The lap side of the formwork did not accidentally collide with the existing concrete pouring surface, no cracks were generated on the existing concrete pouring surface due to the collision of the formwork, and the lining was performed. Cured and cured)
It is possible to improve the quality of the poured concrete, and thus the strength of the tunnel, and the durability of the tunnel.

[Brief description of drawings]

FIG. 1 is a wrap side front view of a formwork lifting control device according to the present invention.

FIG. 2 is an enlarged front view of a detection bar portion of the same.

FIG. 3 is an enlarged side view of an essential part showing a usage state of the same.

FIG. 4 is an enlarged side view of an essential part showing a usage state of a conventional example.

[Explanation of symbols]

12 tunnels 14 concrete 16 formwork 18 Lifting mechanism 24 Detection bar 30 Existing concrete pouring surface

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References Japanese Patent Laid-Open No. 7-26897 (JP, A) Actual Public No. 7-16800 (JP, Y2) (58) Fields investigated (Int.Cl. ⁷ , DB name) E21D 11/10

Claims (2)

(57) [Claims] 1. A formwork in a step of placing a formwork (16) in a tunnel (12) and placing concrete (14) for lining.
The detection bar (24) protruding and retractable at the outer peripheral edge of the lap (16) detects the contact with the existing concrete placing surface (30), and the form (16) when the form (16) is installed ) Is stopped by the lifting mechanism (18) before the contact position with the existing concrete placing surface (30), and then the formwork (16) is moved to the existing concrete placing surface (30).
A method of raising and lowering a formwork, characterized by preventing the generation of cracks due to the collision of the formwork (16) with the existing concrete placing surface (30) by slowly ascending and contacting the formwork. 2. A device for placing a formwork (16) in a tunnel (12) and placing concrete (14) for lining in the formwork.
A detection bar (24) is provided on the outer peripheral edge of the wrap side of (16) so that it can project and retract freely, and the detection bar (24) and the lifting mechanism (18) of the formwork (16) are interlocked with each other. By detecting the contact of the detection bar (24) with the existing concrete placing surface (30), the lifting of the formwork (16) by the elevating mechanism (18) from the position of contact with the existing concrete placing surface (30). Stop at the front and place the existing concrete (3
A mold elevating / lowering control device which prevents the generation of cracks due to the collision of the mold (16) with the (0).