JPH052715Y2 - - Google Patents

Description

[Detailed Description of the Invention] <<Industrial Application Field>> This invention relates to a formwork device, and particularly to a formwork device used in curved construction.

<Prior Art> As is well known, there is a cast-in-place lining method as a type of shield construction method, and in this construction method, the reaction force for moving the shield excavator forward is received by formwork installed behind it.

The formwork used in this type of construction method usually has a length that corresponds to the excavation stroke of the shield excavator, and is assembled in an annular shape.

By the way, when constructing a tunnel using the shield method, it may be necessary to excavate not only in a straight line but also in a curved line, and in this case, the formwork is also installed along the curved line.

During curved construction, the spacing between the joints of the formwork becomes uneven, so in order to adjust this, a formwork such as that shown in, for example, Japanese Patent Application Laid-Open No. 1988-192099 has been proposed.

In the formwork disclosed in this publication, wedges are attached facing each other to the flanges of the formworks to be joined, and these wedges are sandwiched between a pair of tapered members, and the tapered members are aligned in the radial direction of the formwork. By connecting the molds with bolts that pass through the molds, and adjusting the screwing amount of the bolts, it is possible to adjust the spacing between the joints of the formwork, but there are problems described below.

<Problem to be solved by the invention> In other words, as mentioned above, the formwork receives the reaction force of the shield excavator, and this reaction force acts in the axial direction of the formwork. In this formwork, the reaction force is transmitted to the formwork behind it through bolts located at the joints.

In this case, since the bolts are arranged inclined to the formwork, if an extremely large thrust reaction force is applied, a radial shear force acts on the bolts, which may be damaged, making it difficult to reliably maintain the spacing of the joints.

Furthermore, in the formwork disclosed in the above publication, the spacing adjustment mechanism is installed at the joint of the formwork, so it must be set after the trailing formwork is installed, making it difficult to adjust the spacing. .

This idea was devised in view of these problems, and its purpose is to easily adjust the spacing between formwork installed at curved positions, and to create a formwork that can reliably hold this distance. Our objective is to provide a frame device.

《Means for solving the problem》 In order to achieve the above-mentioned purpose, this invention has an annular shape in a formwork device installed at a curved position on the rear side of a shield excavator and receiving its propulsion reaction force. The assembled formwork is divided in the radial direction, and annular flanges are provided protruding from the inner peripheral surfaces of the front and rear parts of the divided parts, and a plurality of annular flanges are installed at intervals in the circumferential direction between these flange parts. and an adjustment piece that has a tapered surface on one end side and is movable in the radial direction and is disposed on the outer periphery of the one flange portion. A fixing base having a tapered surface that makes sliding contact with the tapered surface and is fixed to the outer surface of the other flange portion, and a fixing base that is supported by the one flange portion and moves the adjustment piece in the radial direction to adjust the distance between the front and rear parts. It consists of a spacing adjustment bolt that adjusts the spacing.

<<Operation>> In the formwork apparatus having the above configuration, the propulsion reaction force of the shield tunneling machine is transmitted through the engagement of the tapered surface between the adjustment piece of the interval adjustment mechanism and the fixed base, so that damage is less likely to occur.

In addition, since the interval adjustment mechanism can be disposed in advance between the front and rear divided formworks, the interval can be easily adjusted.

<<Example>> Hereinafter, preferred embodiments of this invention will be described in detail with reference to the accompanying drawings.

FIGS. 1 and 2 show an embodiment of a formwork apparatus according to this invention.

The formwork device shown in the figure divides a formwork 10 assembled into a hollow cylindrical shape in the radial direction into a short front part 12 and a rear part 14 which is longer than the front part.
These are arranged coaxially at predetermined intervals.

Annular flange portions 12a and 14a are provided on the inner circumferential surfaces of the front and rear portions 12 and 14 to protrude from each other, and the outer circumferential frame 12b of the front portion 12 is provided with an annular flange portion 12a and 14a. A ring member 16 that closes the gap is fixed, and the upper surface of the ring member 16 has a spherical shape and is in sliding contact with the inner surface of the outer peripheral frame 14b of the rear part 14.

Between the flange portions 12a and 14a, a plurality of interval adjustment mechanisms 20, the details of which are shown in FIG. 2, are arranged at equal angular intervals in the circumferential direction.

The spacing adjustment mechanism 20 is connected to the flange 1 on the front portion 12 side.
An adjusting piece 28 having one end inserted into a long hole 22 bored in the radial direction of 2a and a stopper nut 24 screwed thereon, and having a tapered surface 26 inclined inward at the other end. , which has tapered grooves 30 on both sides with the same inclination angle, into which the tapered surface 26 of the adjustment piece 28 is fitted, and into which the piece 28 slides along the inclination, and is fixed to the outer surface of the flange portion 14a of the rear part 14. A fixed base 32 is provided.

Further, a screw hole 34 is formed through the adjustment piece 28 in a direction perpendicular to the axis thereof, and a connecting flange 36 fixed to the front end of the front portion 12 and a connecting flange 36 connected to the flange 12 are connected to each other.
A spacing adjustment bolt 40 rotatably mounted on a support member 38 fixed to a is screwed into the screw hole 34.

In the formwork device having the above configuration, when the spacing adjustment bolt 40 is screwed into the screw hole 34, the adjustment piece 28 moves in the radial direction along the elongated hole 22, whereby the tapered surface 26 of the adjustment piece 28 presses the tapered groove 30 of the fixed base 32, and the front and rear parts 12,
The interval between 14 is variable.

In this case, the screwing amount of the spacing adjustment bolt 40 is varied by the spacing adjustment mechanism 20 disposed in the circumferential direction, the spacing between the front part 12 and the rear part 14 is made uneven on the outer circumference, and the front part 12 is made eccentric. When the ring member 16 closes the gap, the outer peripheral frame 14b of the rear part 14
Since the spherical surface is in contact with the spherical surface, adjustment can be easily performed while preventing competition between the two, and sealing performance is also ensured.

Figure 3 shows an example of the state in which the above formwork device is used. In the state shown in the figure, the tunnel is excavated in a downward curved manner, so a half-fold type shield excavator is used. has been done.

The shield excavator includes a front body part 52 having a cutter head 50, a middle body part 54 which is extendable and retractable, and a rear body part 56, and a folding jack is provided between the front body part 52 and the middle body part 54. 58 is disposed, and a propulsion jack 6 is disposed between the middle body part 54 and the rear body part 56.
0 is placed.

Further, a press jack 62 and a reaction force transmitting jack 64 are fixed to the rear body portion 56.

The formwork device is installed adjacent to the existing formwork 66 with the front and middle body parts 52, 54 eccentrically downward and the press jack 62 and reaction force transmission jack 64 contracted.

In this case, the formwork device of the present invention screws the interval adjustment bolts 40 of the interval adjustment mechanism 20 into the screw holes 34 so that the interval between the front part 12 and the rear part 14 becomes larger in the upper part, and the front part 12 is moved downward. It is set in advance so that it is eccentric and follows a curve.

When the reinforcing bars 69 have been incorporated and the concrete has been poured, the press jack 62 and the reaction force transmission jack 63 are expanded, and while the press jack 62 is compressing the poured concrete, the reaction force transmission jack 64 is By receiving the force and contracting the propulsion jack 60, the rear body portion 56 is moved forward.

Here, the reaction force of the reaction force transmission jack 64 is received by the front part 12 and is further transmitted to the rear part 14 and the existing formwork 66 via the adjustment piece 28 and the fixing base 32. In this case, the tapered surface 26 and the tapered groove 30 of the adjustment piece 28 and the fixing base 32 directly engage with each other, so that a reaction force is transmitted and no force is applied to the interval adjustment bolt 40.

Therefore, the distance between the front and rear portions 12, 14 is maintained at a predetermined distance.

Further, since the spacing can be adjusted in advance to follow the curve before assembling to the existing formwork 66, the adjustment becomes easy and construction efficiency is improved.

<<Effects of the invention>> As explained above in detail in the examples, in the formwork device according to this invention, the reaction force of the shield tunneling machine is transmitted rearward without any force acting on the interval adjustment bolts. It is possible to reliably maintain the spacing between the joints of the formwork by preventing damage to the formwork.

[Brief explanation of drawings]

FIG. 1 is an overall perspective view showing an example of the device of the present invention;
FIG. 2 is a sectional view showing the interval adjustment mechanism of the device, and FIG. 3 is an explanatory diagram showing an example of the usage state of the device. 10... Formwork, 12... Front part, 14... Rear part,
20... Spacing adjustment mechanism, 26... Tapered surface, 2
8...adjustment piece, 30...tapered groove, 32...
...Fixing stand, 40... Bolt for spacing adjustment.

Claims (1)

[Scope of utility model registration request] In a formwork device installed at a curved position on the rear side of a shield tunneling machine to receive its propulsion reaction force, the formwork assembled in an annular shape is divided in its radial direction, and the divided front and rear parts are separated. Annular flange portions are respectively provided protruding from the inner circumferential surface, a plurality of spacing adjustment mechanisms are arranged at intervals in the circumferential direction between these flange portions, and the spacing adjustment mechanisms have a tapered surface on one end side. an adjustment piece disposed on the outer surface of the one flange portion so as to be movable in the radial direction;
a fixing base having a tapered surface that comes into sliding contact with the tapered surface of the adjustment piece and is fixed to the outer surface of the other flange portion, and is supported by the one flange portion;
A formwork device comprising: a spacing adjustment bolt that adjusts the spacing between the front and rear portions by moving the adjustment piece in a radial direction.