JPH07556Y2 - Formwork device for tunnel lining - Google Patents

Description

TECHNICAL FIELD The present invention relates to a formwork device for tunnel lining by direct-cast concrete.

2. Description of the Related Art Conventionally, a tunnel lining method using direct-cast concrete is also called a direct-cast concrete lining method. As with this invention, as shown in FIG. 5, a formwork device 2'is installed in an excavation hole excavated by a shield 1. Placed, and with this formwork device 2 ',
In the space between the gable frame 3 adhered to the tail portion of the shield 1 and the ground 4, a direct concrete 5 is cast through the gable frame 3 by a concrete supply device (not shown). The formwork apparatus 2'used at this time uses a formwork in which a plurality of ring-shaped unit formworks formed by detachably connecting a plurality of arc-shaped formwork pieces are connected in series. When the casting of the concrete 5 is completed in this way, the shield 1 is moved forward by the propulsive reaction force of the shield jack 7 pressed against the formwork apparatus 2 ', and when the casting of the concrete is completed in this manner, the assembly is completed. Disassemble the last ring-shaped unit formwork that has been removed, remove this mold, move this ring-shaped unit formwork to the foremost part, reassemble and connect it to another ring-shaped unit formwork,
The concrete pouring is restarted in the same manner as described above, and thereafter, such a process is repeated a desired number of times.

The propulsive reaction force by the jack 7 in this case is obtained by the frictional force and the adhesive force between the formwork device 2'and the concrete 5, and the formwork 16 thereof is shown in FIG. And the surface which comes into contact with the concrete 5 is the formwork device 2 '.
Since it is in line with the transmission direction of the thrust indicated by the arrow, it is not possible to have high expectations for frictional force and adhesive force to counter this thrust, and in order to improve this, the ground contact area must be increased. However, since many molds have to be used for it, there is a problem that the mold device becomes large in size and the mold transportation equipment must be increased. Further, the adhesive force between the formwork 16 and the concrete 5 cannot be restored once they are separated from each other, so that slippage occurs between them and sufficient propulsive force for propelling the shield 1 cannot be obtained. There is.

Therefore, the purpose of the present invention is to solve the problem of the conventional formwork apparatus as described above, and to eliminate the frictional force between the formwork and concrete.
Adhesive force can be increased to obtain a sufficient grounding area even with a small number of molds, thereby making it possible to reduce the size of the mold device and increase the number of mold carrier devices, and to obtain a large propulsion reaction force with a small number of molds. The purpose of the present invention is to provide a formwork device that can be used.

Means for Solving the Problems In order to achieve the above-mentioned object, the present invention is a formwork in which a plurality of ring-shaped unit formworks formed by detachably connecting a plurality of arc-shaped formwork pieces are connected in series. The mold is placed in a hole drilled with a shield, and a gutter frame is installed by a concrete supply device in the space between this form, the gable frame attached to the tail part of the shield, and the ground. In a formwork device for tunnel lining, in which direct-cast concrete is placed to cover the tunnel, the surface of each unit formwork that comes into contact with concrete has a convex portion in the direction intersecting the thrust transmission direction of the shield. It is characterized by that.

The convex portion is formed by forming the surface of each mold into an arcuate surface or an inclined surface, or by providing a protrusion.

Action When concrete is placed by the formwork apparatus of the present invention as described above, in the placed concrete and the surface of the formwork, the protrusions provided on the surface of the formwork intersect the thrust transmission direction. As a result, the ground contact area increases and counters this, and a large bearing pressure is secured, and a small number of molds can be used.

Embodiment 1 In the first embodiment of the present invention shown in FIG. 2, the surface of each mold 11 is a circular arc having a middle height, and in the second embodiment of FIG. To the other side, the inclined surface is inclined from the other side to the other side, and when forming the formwork apparatus 2 with this, a high force is positioned in the front in the excavating direction, and in the third embodiment shown in FIG. A plurality of protrusions 14 are provided on the surface of the frame 13.

As described above, in the formwork device of the present invention, the individual formwork 11, 12, 13 is arranged in the thrust transmission direction, that is, in the horizontal direction.
The shape of does not cause a part of the continuous surface thereof to project in the direction intersecting with it, so that the contact surface with the concrete 5 does not become a straight line in the horizontal direction, so that it is grounded compared to the conventional formwork apparatus 2 '. Since the area is increased, the frictional force with the concrete 5 and the adhesive force are increased to receive a large supporting force, a large propulsive reaction force can be obtained by using a small number of molds.

Advantageous Effects of Invention The present invention is as described above, in which a plurality of ring-shaped unit molds formed by connecting a plurality of arc-shaped mold pieces are connected in series in an excavation hole excavated by a shield. A concrete feeding device is used to place direct-cast concrete through the gable frame in the space between the gable frame attached to the tail part of the shield and the ground. After the installation, the formwork is disassembled, and then reassembled and used again, and in the tunnel lining formwork device for lining the tunnel, the surface of each unit formwork that comes into contact with concrete is shielded. Since it has a convex part in the direction that intersects with the thrust transmission direction, the surface strength of each unit formwork increases, the ground contact area of the formwork surface increases, and the frictional force and adhesive force with concrete increase. Can get a large bearing pressure Therefore, by using a small number of molds, a large propulsive reaction force can be applied to the shield jack, the mold device can be easily assembled and disassembled, work efficiency can be improved, and the molds can be repeatedly used for a long time. It has the effect of being economical to use.

[Brief description of drawings]

FIG. 1 is an explanatory view showing a state in which tunnel lining is performed using the formwork device of the present invention, FIG. 2 is a vertical sectional front view of a first embodiment of the present invention, and FIG. 3 is a second view of the present invention. FIG. 4 is a vertical sectional front view of an embodiment, FIG. 4 is a vertical sectional front view of a third embodiment of the present invention, and FIG. 5 is a vertical sectional front view of a conventional mold device. 1 ... Shield, 2 ... Formwork device 3 ... Wife frame, 4 ... Ground 5 ... Concrete, 7 ... Shield jack 11, 12, 13 ... Formwork

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Tadashi Koyama 2-5-3 Misaki-cho, Chiyoda-ku, Tokyo Inside Tetsuken Construction Co., Ltd. (72) Masaharu Saito 2-3-5 Misaki-cho, Chiyoda-ku, Tokyo (56) References JP-A-63-32095 (JP, A) JP-A-58-191899 (JP, A)

Claims (4)

[Scope of utility model registration request] A ring-shaped unit form formed by connecting a plurality of arc-shaped form pieces is connected in series in an excavation hole excavated by a shield, and the assembled form is arranged. Formwork,
In the gap between the gable frame attached to the tail part of the shield and the ground, direct concrete is placed through the gable frame by the concrete supply device, and after this placement, the formwork is disassembled and then this In a tunnel lining formwork device that repeats reassembling and using to lining a tunnel,
A formwork device for tunnel lining, characterized in that the surface of each unit formwork that comes into contact with concrete has a convex portion in a direction intersecting with the transmission direction of the thrust of the shield. 2. The formwork apparatus for tunnel lining according to claim 1, wherein a surface of the unit formwork that comes into contact with concrete has an arc shape. 3. The formwork apparatus for tunnel lining according to claim 1, wherein the surface of the unit formwork that comes into contact with concrete is an inclined surface along the excavation direction of the tunnel. 4. The formwork device for tunnel lining according to claim 1, wherein a projection is provided on a surface of the unit formwork which comes into contact with concrete.