End formwork fixing device

Abstract

To provide a gable formwork fixing device which can further reduce the burden of installation work of a through member and a gable formwork fixing beam to the gable formwork.SOLUTION: A gable formwork fixing device 10 that supports concrete casting pressure by bringing a through member 40 into contact with a plurality of gable formworks arranged in parallel on the gable face in a casting space between an inner circumferential surface of a tunnel and an arch of tunnel formwork comprises a gable formwork fixing beam 20 supporting the through member 40 at an end located on the gable side and whose tip is movable in the normal direction of the circumference of the formwork and is rotatably installed on a beam support steel material 16 which is shaped along the circumference of the formwork and spans over the gable surface with an interval, and a gas spring 70 functioning as a biasing mechanism that biases the gable formwork fixing beam 20 upward as the tip approaches the inner circumferential surface of the tunnel. The gable formwork fixing beam 20 is equipped with an expansion and contraction mechanism that adjusts the extension length extending from the beam support steel material 16 toward the gable face.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a wife-shaped formwork fixing device in a lining concrete centering.

Background Art

[0002] In the construction of lining concrete for mountain tunnels, a semi-cylindrical movable formwork called a "centering" is used to place concrete on the inner peripheral surface of the tunnel. When placing concrete, at the end of the "centering" which is the construction joint, a wooden board with a width of about 20 cm called a "wife-shaped formwork" is used as a stop formwork and installed so as to block the opening between the natural ground and the "centering". Since the "wife-shaped formwork" is installed and disassembled for each placement using wooden planks, through members, end timbers, and pipe supports, etc., it requires a lot of labor and time.

[0003] The applicant of the present application has proposed a structure in which a wife-shaped formwork fixing device in which a through member made of square pipe and a wife-shaped formwork fixing bar are integrated is installed on a support steel material protruding from the centering for the purpose of labor saving in the installation and disassembly work of the wife-shaped formwork (see Patent Document 1).

Prior Art Documents

[0006] The present invention aims to provide a formwork fixing device that can further reduce the burden of installing through members and formwork fixing beams to the formwork. [Means for solving the problem]

[0007] The end formwork fixing device of the present invention is an end formwork fixing device that supports the concrete pouring pressure by bringing a through member into contact with a plurality of end formworks arranged in parallel on the end face in the pouring space between the inner circumferential surface of the tunnel and the formwork of the centering, and comprises an end formwork fixing beam that supports the through member at the tip located on the side of the end face, and is rotatably installed on a beam support steel material that spans across the end face at a distance from the end face in a shape along the circumferential surface of the formwork so that the tip is movable in the direction normal to the circumferential surface of the formwork, and a biasing mechanism that biases the end formwork fixing beam upward so that the tip approaches the inner circumferential surface of the tunnel, wherein the end formwork fixing beam is equipped with an extension mechanism that adjusts the extension length that extends from the beam support steel material toward the end face. Furthermore, in the end formwork fixing device of the present invention, the end formwork fixing beam may be rotatably installed on the beam support steel material such that its rear end protrudes from the beam support steel material in the direction opposite to the end face. Furthermore, in the end formwork fixing device of the present invention, the biasing mechanism may pull the rear end of the end formwork fixing beam downward, away from the inner circumferential surface of the tunnel. Furthermore, in the end formwork fixing device of the present invention, the end formwork fixing beam is installed on the beam support steel via a support that supports the pivot axis of the end formwork fixing beam, the support includes a column member extending downward from the beam support steel member, and the biasing mechanism may be interposed between the rear end of the end formwork fixing beam and the column member. Furthermore, in the end formwork fixing device of the present invention, the through member is supported by being stretched across two or more end formwork fixing beams, the end formwork fixing beams are installed on the beam support steel via a support that supports the pivot axis of the end formwork fixing beams, and the support may be equipped with a tilt adjustment mechanism for adjusting the tilt of the pivot axis. [Effects of the Invention]

[0008] According to the present invention, after the end formwork is installed, the through members can be easily installed on the end formwork simply by adjusting the extension length of the end formwork fixing beams, thus reducing the burden of the work required to install the through members and end formwork fixing beams on the end formwork. [Brief explanation of the drawing]

[0009] [Figure 1] This figure shows the configuration of a centering structure with the gable formwork fixing device according to the present invention installed. [Figure 2] Figure 1 shows the centering structure as viewed from the face side. [Figure 3] This is a perspective view showing the configuration of the gable formwork fixing device according to the present invention. [Figure 4] Figure 3 is a side view showing the configuration of the fixed beams of the gable formwork in a set state. [Figure 5] Figure 3 is a perspective view showing the configuration of the gripping section. [Figure 6] Figure 3 is a side view showing the configuration of the lumbar spine. [Figure 7] Figure 3 is a perspective view showing the configuration of the support structure. [Figure 8] Figure 3 shows an example of how the support device is installed on the beam support steel material. [Figure 9] Figure 3 is a side view showing the configuration of the retracted formwork fixing beams. [Modes for carrying out the invention]

[0010] Next, embodiments for carrying out the present invention (hereinafter simply referred to as "embodiments") will be specifically described with reference to the drawings.

[0011] Referring to FIG. 1, the side form fixing device 10 of the present embodiment is installed on the center 1 having an arch-shaped formwork 11 along the inner peripheral surface of the tunnel that is temporarily supported by means such as spraying concrete, and supports a side form that closes the side surface of the placing space (hereinafter simply referred to as the placing space C) formed between the inner peripheral surface of the tunnel and the center 1 (formwork 11).

[0012] The center 1 is capable of traveling on the rails 2 respectively laid along the tunnel axis direction (the construction direction of the lining concrete). When the lining concrete is constructed from the shaft side toward the face side, a plurality of the side form fixing devices 10 are installed on the face side of the center 1 along the circumferential length of the formwork 11.

[0013] The formwork 11 is a steel member having a substantially semi-arc-shaped cross-sectional shape in the tunnel width direction so as to follow the inner peripheral surface of the tunnel. As shown in FIG. 2, the formwork 11 is supported by a moving gantry 13 via a plurality of jacks 12. And the space between the formwork 11 and the inner peripheral surface of the tunnel becomes the placing space C.

[0014] The moving gantry 13 is composed of H-shaped steel, channel steel, etc., and includes a plurality of portal frames 14 arranged front and rear, and a plurality of vertical beam members (not shown) connecting the plurality of portal frames 14. Wheels for traveling on the rails 2 are provided at the lower end portions of the portal frames 14. The inner space cross-section of the portal frame 14 functions as a tunnel for transporting muck, etc.

[0015] The center 1 (formwork 11) includes a plurality of projecting steel members 15 that project from the side surface side in the face direction at predetermined intervals along the circumferential length of the formwork 11, and a lip receiving steel member 16 fixed to the plurality of projecting steel members 15. The lip receiving steel member 16 has a shape along the circumferential length of the formwork 11 and is spanned with a space from the side surface of the placing space C. The side form fixing device 10 is installed on the lip receiving steel member 16.

[0016] Referring to FIGS. 3 and 4, the side form fixing device 10 is a device that abuts against a plurality of side forms 3 arranged side by side on the side surface of the placement space C to support the concrete placement pressure. The side form fixing device 10 includes three side form fixing bars 20, a through member 40, three supports 50, and a gas spring 70.

[0017] Reference numeral 17 shown in FIG. 4 is an angle member spanned at an interval from a formwork side surface 11a extending from the front end side of the formwork 11 toward the inner circumference. The angle member 17 functions as a dropout prevention member for preventing the side form 3 from dropping off, and also functions as a fixing member for fixing the side form 3 by driving a wedge 4 (wedge) between the angle member 17 and the side form 3.

[0018] The side form fixing bar 20 is a rod-shaped member provided with a telescopic mechanism for adjusting the extension length extending from the bar receiving steel member 16 toward the side surface of the placement space C. In this embodiment, a pipe support which is a temporary member is used. The side form fixing bar 20 is installed such that the tip located on the side of the side surface of the placement space C is movable in the normal direction of the circumference of the formwork 11, and the middle part is rotatable on the bar receiving steel member 16. Hereinafter, the direction approaching the inner peripheral surface of the tunnel is referred to as the upward direction, and the direction moving away from the inner peripheral surface of the tunnel is referred to as the downward direction. The telescopic mechanism of the side form fixing bar 20 is not limited in its structure as long as it can maintain a predetermined strength against the force in the direction of compressing the shaft in the adjusted length state. The telescopic mechanism of the side form fixing bar 20 can also use a cylinder or the like that expands and contracts hydraulically or electrically.

[0019] The side form fixing bar 20 includes a cylindrical (pipe-shaped) insertion pipe 21 and a cylindrical waist pipe 22. The rear end of the insertion pipe 21 is inserted into the waist pipe 22, and a gripping portion 30 is attached to the tip instead of a receiving plate.

[0020] The gripping portion 30 is a gripping mechanism for gripping a through member 40, which is made of a hollow pipe with a circular cross-section, such as a single pipe. Referring to Figure 5, the gripping portion 30 comprises a pipe receiving portion 31 in which a recess having approximately the same curvature as the outer circumference of the through member 40 is formed, and a movable portion 32 with one end pivotally supported. The movable portion 32 is rotated toward the pipe receiving portion 31 by tightening the bolt 33, and grips the through member 40 between itself and the pipe receiving portion 31.

[0021] The through member 40 is gripped by gripping parts 30 attached to the ends of the three end formwork fixing beams 20, and functions as a contact part that abuts against the multiple end formworks 3 arranged in parallel on the end face of the pouring space C. The number of end formwork fixing beams 20 and the length of the through member 40 in the end formwork fixing device 10 can be set appropriately considering the concrete pouring pressure.

[0022] The waist pipe 22 has its base plate removed and the insertion pipe 21 passes through it. Referring to Figure 6, the waist pipe 22 comprises a shaft base 23 formed approximately in the middle of its outer circumference and a fixing plate 24 formed at the rear end of its outer circumference.

[0023] The end formwork fixing beam 20 is rotatably installed on the beam support steel member 16 by a support member 50. The support member 50 consists of a rotatable support part 51 and an extension part 58.

[0024] Referring to Figure 7(a), the rotating support section 51 comprises a seat plate 52 fixed to the upper flange of the beam support steel member 16, and a pair of bearing plates 53 erected at a predetermined distance from each other on the upper surface of the seat plate 52 and facing each other. The pair of bearing plates 53 each have bearing holes formed at opposing positions, and these bearing holes support the rotating shafts 54a and 54b, which are made up of bolts or the like.

[0025] The pivot shaft 54a is inserted through the bearing hole 23a of the pivot base 23 of the end formwork fixing beam 20, and serves as the central axis of rotation for the end formwork fixing beam 20. Since the pivot base 23 is formed approximately in the middle of the waist pipe 22, the weight of the end formwork fixing beam 20 is distributed to the left and right of the pivot shaft 54a, allowing the end formwork fixing beam 20 to be rotated with little force.

[0026] The base plate 52 is rectangular in shape and has adjustment screws 55 at each of its four corners. The adjustment screws 55 are an adjustment mechanism that adjusts the inclination of the pivot shaft 54a (base plate 52) by adjusting the length of the base plate 52 that protrudes downward. With the inclination of the base plate 52 adjusted by the adjustment screws 55, the base plate 52 is fixed to the upper flange of the beam support steel material 16 by tightening the fixing bolts 57 of the fixing angle 56 that extends to the lower part of the upper flange of the beam support steel material 16.

[0027] The beam support steel member 16 is shaped to conform to the circumference of the formwork 11. Therefore, if the rotation support part 51 (seat plate 52) that supports the rotation of the three end formwork fixing beams 20 is fixed directly to the upper flange of the beam support steel member 16, the rotation axes 54a of the three end formwork fixing beams 20 will each have different inclinations, as shown in Figure 8(a). In this case, the distance between the tips of the three end formwork fixing beams 20 changes with rotation. Consequently, the three end formwork fixing beams 20, whose tips are connected by a through member 40, cannot be smoothly rotated or extended due to the friction between the rotation axis 54a and the shaft base 23 (bearing hole 23a), and between the insertion pipe 21 and the waist pipe 22.

[0028] Therefore, in this embodiment, the inclination of the pivot shaft 54a (base plate 52) can be adjusted by the adjustment screw 55. By adjusting the inclination of the pivot shaft 54a (base plate 52) with the adjustment screw 55, the pivot shafts 54a of the three end formwork fixing beams 20 can be set parallel, as shown in Figure 8(b). As a result, the gap is eliminated, and the three end formwork fixing beams 20, whose ends are connected by through members 40, can be rotated and extended smoothly.

[0029] Referring to Figure 7(b), the extension 58 comprises a pair of bearing plates 59 facing each other and a column member 60 extending downward from the beam support steel member 16. The pair of bearing plates 59 each have bearing holes 59a formed at opposing positions, and the extension 58 including the bearing plates 59 is fixed by passing the pivot shaft 54b through the bearing holes 59a. The pair of bearing plates 59 of the extension 58 are positioned between a pair of bearing plates 53 of the rotation support part 51, and the shaft base 23 of the end formwork fixing beam 20 is pivotally supported by the pivot shaft 54a located between the pair of bearing plates 59 of the extension 58. The rotation support part 51 is also fixed to the lower flange of the beam support steel member 16 by a hook part 61 in conjunction with a fixing bolt 57.

[0030] The column member 60 is fixed to the lower flange of the beam support steel member 16 by a hook portion 61, and a fixing plate 62 is formed at its lower end.

[0031] The gas spring 70 is interposed between the fixing plate 24 of the waist pipe 22 and the fixing plate 62 of the extension 58. One end of the gas spring 70 is pivotally supported by the bearing hole 24a of the fixing plate 24, and the other end is pivotally supported by the bearing hole 62a of the fixing plate 62.

[0032] The gas spring 70 is a retractable type and functions as a biasing mechanism that pulls the rear end of the end formwork fixing beam 20 downward, thereby biasing the front end of the end formwork fixing beam 20 upward. The retraction force of the gas spring 70 is set to a force that slowly moves the front end of the end formwork fixing beam 20 upward. In the example shown in Figure 3, the gas spring 70 is installed only on the middle end formwork fixing beam 20, but there are no restrictions on which end formwork fixing beams 20 the gas spring 70 is installed on, and the number of gas springs 70 installed can be set appropriately according to their retraction force.

[0033] In this embodiment, the biasing mechanism, a gas spring 70, is installed on the face side of the beam support steel member 16. Therefore, the gas spring 70, which is the biasing mechanism, does not obstruct the working space between the end face of the casting space C and the beam support steel member 16, thereby improving work efficiency. If there is sufficient working space, the gas spring 70 can also be installed as an extrusion type between the end face of the casting space C and the beam support steel member 16.

[0034] The gas spring 70 is an example of a biasing mechanism and can be replaced with a mechanism using various springs having an appropriate biasing force. Alternatively, the pivot shaft 54a and the end formwork fixing beam 20 may be fixed together, and the biasing mechanism may bias the pivot shaft 54a in the rotational direction.

[0035] The pair of bearing plates 59 of the extension 58 are provided with stopper holes 59b formed in opposing positions so as not to overlap with the pair of bearing plates 53 of the rotation support 51. The stopper holes 59b are located on the rear end side of the end formwork fixing beam 20, relative to the rotation shaft 54a.

[0036] As shown in Figure 9, by shortening the extension length of the end formwork fixing beam 20 and pushing down its tip, the pin 5 is inserted into the stopper hole 59b, thereby restricting the rotation of the end formwork fixing beam 20 due to the biasing force of the gas spring 70. In this state, the through member 40 at the tip of the end formwork fixing beam 20 is retracted from the end face of the pouring space C. Therefore, the end formwork fixing device 10 does not get in the way even when centering in the reinforced concrete section.

[0037] When the pin 5 inserted into the stopper hole 59b is removed, the end formwork fixing beam 20 is rotated by the biasing force of the gas spring 70, and the tip of the end formwork fixing beam 20 moves upward. Therefore, the worker can adjust the extension length of the end formwork fixing beam 20 using the telescopic mechanism and set the through member 40 in contact with the end formwork 3 at an appropriate position according to the thickness of the concrete pouring space C, as shown in Figure 4. In other words, the biasing force of the gas spring 70 can assist manual work and improve the operability of the up and down movement of the through member 40.

[0038] As described above, this embodiment is a formwork fixing device 10 that supports the concrete pouring pressure by bringing a through member 40 into contact with a plurality of formworks 3 arranged in parallel on the end face of the pouring space C between the inner surface of the tunnel and the formwork 11 of the centering 1. The device includes a formwork fixing beam 20 that supports the through member 40 at the end located on the end face side, and is rotatably installed on a beam support steel member 16 that spans the end face at a distance from the end face in a shape that follows the circumference of the formwork 11, with the end being movable in the direction normal to the circumference of the formwork 11, and a gas spring 70 that functions as a biasing mechanism that biases the formwork fixing beam 20 upward in a direction that approaches the inner surface of the tunnel, and the formwork fixing beam 20 is equipped with an extension mechanism that adjusts the extension length that extends from the beam support steel member 16 toward the end face. With this configuration, after the end formwork 3 is installed, the through members 40 can be easily installed on the end formwork 3 simply by adjusting the extension length of the end formwork fixing beams 20, thus further reducing the burden of the installation work of the through members 40 and end formwork fixing beams 20 on the end formwork 3. In other words, the biasing force of the gas spring 70 assists manual work, improving the operability of the up and down movement of the through members 40. As a result, workers can concentrate on fine-tuning the extension length of the end formwork fixing beams 20, making the work easy even for one person, and preventing problems such as the end formwork 3 coming loose or moving, regardless of who is performing the work.

[0039] After concrete pouring is complete, the through members 40 and end formwork fixing beams 20 can be easily removed from the end formwork 3 by retracting the expansion mechanism. This eliminates the need to install and remove the through members 40 and end formwork fixing beams 20 from the centering tool 1 after each concrete pour, allowing for quick and easy fixing of the end formwork 3.

[0040] Furthermore, in this embodiment, the end formwork fixing beam 20 is rotatably installed on the beam support steel 16 such that its rear end protrudes from the beam support steel 16 in the direction opposite to the end face. This configuration distributes the weight of the end formwork fixing beam 20 to both sides of the pivot axis 54a, making the tip of the end formwork fixing beam 20 lighter. As a result, the end formwork fixing beam 20 can be rotated with less force, further improving its operability.

[0041] Furthermore, in this embodiment, the gas spring 70 pulls the rear end of the end formwork fixing beam 20 downward, away from the inner circumferential surface of the tunnel. This configuration allows the biasing mechanism, the gas spring 70, to work without obstructing the workspace between the end face of the casting space C and the beam support steel member 16, thereby improving work efficiency.

[0042] Furthermore, in this embodiment, the end formwork fixing beam 20 is installed on the beam support steel member 16 via a support member 50 that supports the pivot axis 54a of the end formwork fixing beam 20, the support member 50 comprises a column member 60 extending downward from the beam support steel member 16, and the gas spring 70 is interposed between the rear end side (fixing plate 24) of the end formwork fixing beam 20 and the column member 60 (fixing plate 62). This configuration allows the rear end of the end formwork fixing beam 20 to be pulled downward by the gas spring 70.

[0043] Furthermore, in this embodiment, the through member 40 is supported by being stretched across two or more end formwork fixing beams 20, and the end formwork fixing beams 20 are installed on the beam support steel members 16 via a support member 50 (rotation support part 51) that supports the pivot axis 54a of the end formwork fixing beam 20, and the support member 50 (rotation support part 51) is equipped with a tilt adjustment mechanism that adjusts the tilt of the pivot axis 54a. This configuration allows each of the pivot axes 54a to be set parallel, so that the three end formwork fixing beams 20, whose ends are connected by through members 40, can be rotated and extended smoothly.

[0044] The present invention has been described above based on the embodiments. These embodiments are illustrative, and it will be understood by those skilled in the art that various modifications are possible in the combination of these components, and that such modifications also fall within the scope of the present invention. [Explanation of symbols]

[0045] 1 Centre 2 rails 3. Gable formwork 4 Camber 5 pins 10 End formwork fixing device 11 Formwork 11a Formwork end face 12 Jacks 13 Mobile stand 14 Gate-type frame 15. Overhanging steel members 16. Beam support steel 17 Angle material 20. End formwork fixing beam 21. Insert pipe 22 Lumbar tube 23 axis pedestal 23a Bearing hole 24 Fixing plate 24a Bearing hole 30 Gripping part 31 Pipe support 32 Moving parts 33 volts 40 through-beams 50 Supports 51 Rotating support section 52 Seat board 53 Bearing plate 54a, 54b Rotary shafts 55 Adjustment screw 56 Fixed angle 57 Fixing bolts 58 Extension section 59 Bearing plate 59a Bearing hole 59b Stopper hole 60 Pillar material 61 Hook part 62 Fixing plate 62a Bearing hole 70 Gas springs C. Concrete pouring space

Claims

1. A formwork fixing device for supporting concrete placement pressure by bringing through members into contact with multiple end formworks arranged side by side on the end face in the placement space between the inner surface of the tunnel and the formwork of the centering structure, The end of the through member is supported at the end located on the side of the end face, and the end is rotatably mounted on a beam support steel member that spans across the end face at a distance from it in a shape that follows the circumference of the formwork, so that the end can move in the direction normal to the circumference of the formwork. The system includes a biasing mechanism that biases the end formwork fixing beam upward so that its tip approaches the inner circumferential surface of the tunnel, The end formwork fixing device is characterized in that the end formwork fixing beam is equipped with an extension mechanism for adjusting the extension length that extends from the beam support steel material toward the end face.

2. The end formwork fixing device according to claim 1, characterized in that the end formwork fixing beam is rotatably installed on the beam support steel material such that its rear end protrudes from the beam support steel material in the direction opposite to the end face.

3. The end formwork fixing device according to claim 2, characterized in that the biasing mechanism pulls the rear end of the end formwork fixing beam downward, away from the inner circumferential surface of the tunnel.

4. The end formwork fixing beam is installed on the beam support steel via a support that supports the pivot axis of the end formwork fixing beam, The support member comprises a column member extending downward from the beam support steel member, The gable formwork fixing device according to claim 3, characterized in that the biasing mechanism is interposed between the rear end of the gable formwork fixing beam and the column member.

5. The aforementioned through member is supported by being stretched across two or more of the aforementioned end formwork fixing beams. The end formwork fixing beam is installed on the beam support steel via a support that supports the pivot axis of the end formwork fixing beam, The formwork fixing device according to claim 1, characterized in that the support member is provided with a tilt adjustment mechanism for adjusting the tilt of the pivot shaft.

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