Methods for constructing and dismantling a concrete formwork device

Abstract

To construct a concrete form device for a tunnel lining concrete molding in a short period of time.SOLUTION: A rear wall divider 21b, which constitutes a side wall 21 of a gantry 12, is installed on both sides of a tunnel, and a beam material 22 is stretched between upper parts of the rear wall dividers 21b. Next, a top form 31 is installed on an upper part of the beam material 22. Then, a front wall divider 21a is connected to the rear wall divider 21b, and the beam material 22 is stretched between the front wall dividers 21a, and the top form 31 is installed on the upper part of the beam material 22. In this way, a form upper body 15 is assembled. Next, the form upper body 15 is raised by a side jack 42 to attach legs to a lower part of the form upper body 15, and then the side jack 42 is removed.SELECTED DRAWING: Figure 17

Description

[Technical Field]

[0001] The present invention relates to a method for constructing a concrete formwork device for forming tunnel lining concrete and a method for dismantling the device. [Background technology]

[0002] Patent Document 1 discloses a concrete formwork device for forming tunnel lining concrete. This concrete formwork device is provided with an arch-shaped form assembly that forms the outer shell of the device. The inner surface of the tunnel lining concrete is formed by the outer surface of this form assembly. The form assembly is composed of a top form located at the top and another form located below the top form. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2017-186882 Summary of the Invention [Problem to be solved by the invention]

[0004] When constructing a concrete formwork system in a tunnel, a crane is installed away from the concrete formwork system in the tunnel extension direction. The top form is then suspended by the crane's boom and transported to a predetermined installation position. Therefore, the range of movement of the top form is limited not only by the lifting range and swing radius of the crane's boom, but also by the length of the boom. For this reason, the concrete formwork system cannot be longer than the range of movement of the crane's boom. On the other hand, if the concrete formwork system is long in the tunnel extension direction, a large crane with a long boom is required. However, because the tunnel height is limited and the crane's swing axis is located low, if the crane's boom is extended too far, the tip of the crane may collide with the upper inner wall of the tunnel or the underside of the crane may interfere with the concrete formwork system. Therefore, even with a large crane, it is not possible to construct a concrete formwork that is long in the tunnel extension direction. Therefore, the lining concrete must be cast using a concrete formwork that is short in the tunnel extension direction. As a result, the number of pours of lining concrete increases, lengthening the tunnel construction period. [Means for solving the problem]

[0005] In the method for constructing a concrete formwork device of the present invention, a concrete formwork device is provided that supports a plurality of form assemblies on a gantry having side walls located on both the left and right sides of a tunnel, legs at the bottom of the side walls, and beams erected between the upper ends of the side walls, and the gantry has a plurality of gantry segments that are connected in the extension direction of the tunnel. In this method for constructing a concrete formwork device, the gantry segments located on the end sides of the gantry are constructed, and then a top form that forms the top of the form assemblies is supported on the top of the gantry segments, and then another gantry segment is constructed and connected to the existing gantry segment and the top form is supported in the same way, and then the entire gantry segment is raised, the legs are attached, and another form is connected to the bottom of the top form.

[0006] Therefore, when constructing a concrete formwork system, gantry segments are constructed and a top form is supported on each gantry segment. Then, the gantry with multiple gantry segments connected together can be raised to assemble the legs and other forms below the top form. This eliminates the need to support the top form on a gantry that is long in the tunnel extension direction, reducing restrictions on assembling the top form using a crane. This makes it possible to shorten the construction period. Furthermore, by connecting the gantry segments, a concrete formwork system that is long in the tunnel extension direction can be constructed. This reduces the number of times the lining concrete needs to be poured, thereby shortening the tunnel construction period.

[0007] The method for dismantling a concrete formwork device of the present invention is a concrete formwork device in which a plurality of form assemblies are supported on a gantry having side walls located on both the left and right sides of a tunnel, legs of the side walls, and beams erected between the upper ends of the side walls, and the gantry is made up of a plurality of gantry segments connected in the extension direction of the tunnel and has legs.In this method for dismantling a concrete formwork device, the gantry is characterized in that after removing other forms below the top form, the legs are removed, and then the gantry is lowered together with the top form, and the top form is removed and the gantry segments are disassembled one by one, starting from the gantry segment located on the end side in the extension direction of the tunnel.

[0008] Therefore, when dismantling the concrete formwork system, the top form can be disassembled into separate gantry sections, which are shorter at the front and rear. This reduces restrictions on crane use and allows for easier dismantling in a shorter time, thereby shortening the construction period for tunnel construction. [Effects of the Invention]

[0009] The present invention has the effect of shortening the construction period of a tunnel. [Brief explanation of the drawings]

[0010] [Figure 1] 3 is a cross-sectional view showing the state in which lining concrete is being poured by the concrete formwork device of the first embodiment. FIG. [Figure 2] 1 is a perspective view of a concrete formwork device according to a first embodiment. [Figure 3] FIG. 10 is a perspective view showing the installation state of the rear wall segment. [Figure 4] FIG. 10 is a perspective view showing a state in which a side jack is installed on a rear wall section. [Figure 5] FIG. 10 is a perspective view showing a state in which a beam member is installed in the rear wall section. [Figure 6] FIG. 10 is a perspective view showing the state in which the beams and support plate are installed on the rear wall section. [Figure 7] FIG. 10 is a perspective view showing the state in which scaffolding and the like are installed on the rear gantry divided body. [Figure 8] FIG. 10 is an exploded perspective view showing the top form being installed on the rear gantry division. [Figure 9] FIG. 10 is a perspective view showing the top form installed on the rear gantry division. [Figure 10] FIG. 10 is a perspective view showing the state in which the front gantry divided body is installed. [Figure 11] FIG. 10 is a perspective view showing the state in which side jacks are installed on the front gantry section. [Figure 12] FIG. 10 is a perspective view showing the top form installed on the front gantry division. [Figure 13] FIG. 10 is a perspective view showing the side jack in an extended state. [Figure 14] FIG. 10 is a perspective view showing the state in which the front main legs and running gear are attached. [Figure 15] FIG. 10 is a perspective view showing the state in which the main legs and running devices are attached to the four corners of the upper body of the formwork. [Figure 16] FIG. 10 is a perspective view showing the state in which an intermediate leg is attached to the upper body of the formwork. [Figure 17] FIG. [Figure 18] FIG. 10 is a cross-sectional view showing the pouring of lining concrete by the concrete formwork device of the second embodiment. [Figure 19]FIG. 10 is a perspective view of the concrete formwork device of the second embodiment, with the form assembly removed. [Figure 20] A front view showing the formwork upper body in the lowered state. [Figure 21] A front view showing the formwork upper body in the raised state. DETAILED DESCRIPTION OF THE INVENTION

[0011] (First embodiment) A first embodiment of the present invention will now be described with reference to FIGS. 1 to 17. FIG. <Configuration of concrete formwork device 11> First, the configuration of a concrete formwork device 11 for forming tunnel lining concrete (hereinafter referred to as formwork device) will be described.

[0012] As shown in Figures 1 and 2, a pair of parallel rails R are laid on the ground S of a tunnel T along the extension direction of the tunnel. In this embodiment, the extension direction of the tunnel T (the direction perpendicular to the paper surface of Figure 1) is the front-to-rear direction, and the left side of Figure 2 is the front side in the front-to-rear direction. A formwork device 11 of the embodiment is supported on the rails R so as to be movable along the extension direction of the rails R.

[0013] The formwork device 11 includes a portal-shaped gantry 12 and multiple (seven in this embodiment) arch-shaped form assemblies 14 supported on the gantry 12 via support columns 13 between the upper ends of the support columns 13. The gantry 12 includes side walls 21 on both sides in the tunnel extension direction (the width direction of the tunnel T) and multiple beams 22 installed at intervals in the front-to-rear direction between the upper portions of the side walls 21. The left and right side walls 21 are formed by connecting a front wall segment 21a and a rear wall segment 21b. The front wall segment 21a and the beams 22 installed therebetween form a front gantry segment 12a. The rear wall segment 21b and the beams 22 installed therebetween form a rear gantry segment 12b. The formwork upper body 15 is composed of the front gantry divided body 12a, the rear gantry divided body 12b, the top form 31, a support plate 44 (described later), the support columns 13, and the like.

[0014] 1 and 17, main legs 26 and auxiliary legs 27 are provided at the bottom of the four corners of the form upper body 15. Wheels 24 that roll on rails R and traveling devices 25 that have a motor (not shown) that rotates and drives the wheels 24 are attached to the lower ends of the main legs 26 and auxiliary legs 27. The auxiliary legs 27 are made up of extendable jacks.

[0015] A plurality of intermediate legs 28 are attached to the lower end of the form upper body 15, i.e., the lower end positions of the side walls 21, between the front and rear main legs 26 and auxiliary legs 27. Each intermediate leg 28 has an upper half 28a attached to the side wall 21 and a lower half 28b facing the ground S so as to be movable toward and away from the ground S.

[0016] 1 and 2, the form assembly 14 is composed of a top form 31 located at the top, side forms 32 connected to both ends of the top form 31, and an inverted form 33 connected to the lower end of the side form 32. In this embodiment, each member constituting the formwork device 11 is detachably attached to other members by bolts (not shown), but the connection between the side forms 32 and the inverted forms 33 is made by hinges. However, the side forms 32 and the inverted forms 33 are fixed to the side surfaces of the gantry 12 via jacks (not shown).

[0017] Then, tunnel lining concrete (hereinafter referred to as concrete) C is poured between the form assembly 14 and the inner peripheral surface of the tunnel T, and the inner peripheral surface of the concrete C is formed by this form assembly 14.

[0018] <Method for constructing formwork device 11> Next, a method for constructing the formwork device 11 will be described. First, as shown in Figures 3 and 4, the rear wall section 21b is installed at one end in the tunnel extension direction on both rails R laid along the extension direction of the tunnel T on the ground S of the tunnel T. At this time, multiple support members 41 are attached to both sides of the lower end of the rear wall section 21b. These support members 41 rest on the ground S to keep the rear wall section 21b in an upright position.

[0019] At the same time, as shown in Figure 4, side jacks 42 in a contracted state are attached and connected to the inner surface in the tunnel width direction (left-right direction) at the rear end of the rear wall section 21b. These side jacks 42 are fixed to the side surfaces of the vertical members of the truss that make up the rear wall section 21b while standing on the ground S.

[0020] Next, as shown in Figure 5, a plurality of diagonal brace members 43 for supporting the beam members 22 and reinforcing the rear wall section 21b are fixed at predetermined intervals to the inner surfaces of the vertical members of the truss of the rear wall section 21b.

[0021] Next, as shown in Figures 5 and 6, the beams 22 are placed and fixed between the upper surfaces of the left and right rear wall sections 21b, the diagonal brace members 43, and the side jacks 42. Here, the truss vertical members are arranged at a predetermined pitch on the rear wall section 21b, but the diagonal brace member 43 is not attached to the front-end vertical member. For this reason, a protrusion 211 is formed on the rear wall section 21b forward of the front-end diagonal brace member 43. The length of this protrusion 211 in the front-to-rear direction is half the arrangement pitch of the beams 22 in the front-to-rear direction.

[0022] 1 and 6, support plates 44 for receiving the lower ends of the top form 31 are fixed to the upper left and right ends of the form upper body 15 at the position of the beams 22. In this way, the rear gantry divided body 12b, which is the rear half of the form upper body 15, is formed.

[0023] Thereafter, as shown in FIG. 7, scaffolding boards 45, which will serve as footholds for workers to construct the formwork device 11, reinforcing materials 46, and the like are placed at required positions between the front and rear beams 22. Then, as shown in Figures 8 and 9, multiple support columns 13 are erected on each beam 22. Then, top forms 31 are placed on the support columns 13 and fixed. Adjacent top forms 31 in the front and rear are fixed to the same support columns 13 at both front and rear ends. That is, as shown in Figure 9, the lower edges of the front-to-rear end plates of the top forms 31 are placed on the front-to-rear half of the upper end faces of the support columns 13. In this way, three top forms 31 are supported between four sets of support columns 13 in the front and rear. In this way, the top forms 31 are installed on the rear wall partition 21b.

[0024] Next, as shown in Figure 10, the left and right front wall segments 21a are installed on both rails R at the front side of the rear wall segment 21b, i.e., at the other end in the tunnel extension direction. The rear end faces of the front wall segments 21a are then connected and fixed to the front end face of the existing rear wall segment 21b. In this case, since the front wall segment 21a is connected to the rear wall segment 21b and stands upright, support members 41 do not need to be used, but may be used depending on the condition of the ground surface S, etc.

[0025] 11, for the front wall section 21a, diagonal brace members 43 are attached to the vertical members of the truss in the same manner as for the rear wall section 21b. In this case, however, diagonal brace members 43 are not attached to the vertical members at the front ends of the truss of the front wall section 21a. Also, rearward of the rear-end diagonal brace member 43, the front wall section 21a has protrusions 212 with a length half the arrangement pitch of the beam members 22 in the fore-and-aft direction. Therefore, the diagonal brace members 43 of the front and rear wall sections 21a, 21b are arranged at equal intervals.

[0026] 11, another side jack 42 is attached to the vertical member that does not have the front end diagonal brace member 43 on the inner surface of the front wall section 21a so as to be located on the opposite side in the tunnel extension direction from the rear side jack 42. This front side jack 42 is placed on the ground S in the same way as the rear side jack 42.

[0027] 12, similarly to the case of the rear wall section 21b, beams 22 are placed and fixed between the upper surfaces of the front wall section 21a, the diagonal braces 43, and the side jacks 42. In this case, the number of beams 22 is the same as that of the rear wall section 21b.

[0028] Then, the support plate 44 is attached in the same manner as described above. In this way, the front gantry divided body 12a is formed, which constitutes the front half of the form upper body 15. Thereafter, scaffolding boards 45 and the like are attached, and the supports 13 are erected on the beams 22.

[0029] Then, as shown in FIG. 12, a top form 31 is placed on the support columns 13. In this case, since protrusions 211, 212 are formed at the rear end of the front wall section 21a and the front end of the rear wall section 21b, one top form 31 (31a) is also positioned at the protrusions 211, 212. As a result, in addition to the three top forms 31 on the front wall section 21a and the three on the rear wall section 21b, a total of one top form 31 is placed. Therefore, this one top form 31 spans between the front wall section 21a and the rear wall section 21b, in other words, between the front gantry section 12a and the rear gantry section 12b. Therefore, a total of seven top forms 31 are supported on the form upper body 15. As a result, the entire form upper body 15 is constructed.

[0030] Next, as shown in Figure 13, all side jacks 42 are extended to raise the form upper body 15, which is made up of all gantry segments 12a and 12b. Then, as shown in Figures 14 and 15, the main legs 26 are attached to the underside of the four corners of the form upper body 15. Thereafter, the traveling devices 25, which are capable of traveling on rails R, are positioned below the main legs 26 and auxiliary legs 27, and all side jacks 42 are retracted to place the main legs 26 on the traveling devices 25. The auxiliary legs 27 are attached to the four corners of the form upper body 15 before the side jacks 42 are attached.

[0031] Thereafter, as shown in FIG. 15, the auxiliary legs 27 made of jacks are extended and placed on the traveling device 25. Next, as shown in Figures 16 and 17, the upper half 28a of the intermediate leg 28, which is a member used to construct the concrete formwork apparatus 11, is attached to the lower surface of the lower frame of the truss of both wall sections 21a, 21b. In this case, a loading plate P is fixed to the upper surface of the forks F of a forklift L. The upper half 28a is then attached in an upright position on the upper surface of the loading plate P so that it will not move even when the forklift L travels. The upper half 28a is moved to the lower frame as the forklift L travels.

[0032] Thereafter, upper half 28a is detached from mounting plate P and attached to the underside of the lower frame. Next, lower half 28b, which is made up of a jack, is attached to the lower end of upper half 28a. This lower half 28b is placed on the ground S by adjusting its vertical length. Therefore, intermediate legs 28 receive the load acting on side wall 21 from poured concrete C, preventing deformation of side wall 21.

[0033] In this manner, the gantry 12 is assembled. Then, as shown in Figures 1 and 2, the side forms 32 are connected to the lower ends of both sides of the top form 31, and the invert forms 33 are connected to the lower ends of the side forms 32. Thereafter, the side jacks 42 are separated from the formwork upper body 15, contracted, and removed.

[0034] In this way, as shown in FIGS. 1 and 2, a formwork device 11 used for forming concrete C is constructed. <Method for dismantling formwork device 11> When dismantling the formwork device 11, the dismantling work proceeds in the reverse order to that of construction.

[0035] That is, in the method of dismantling the formwork apparatus 11, the side forms 32 and invert forms 33 below the top form 31 are removed, and side jacks 42 are attached and connected to the four corners of the gantry 12. At this time, the side jacks 42 are extended. After that, the auxiliary legs 27 are retracted, and the traveling devices 25 are removed, and the main legs 26 and intermediate legs 28 are removed. Next, the side jacks 42 are retracted to lower the formwork upper body 15 including the gantry 12 and top form 31. Then, the formwork apparatus 11 is dismantled and removed by removing the top form 31 and disassembling the gantry segments 12a, 12b in order, starting from the gantry segment 12b located at the end side in the tunnel extension direction.

[0036] (Effects of the embodiment) This embodiment has the following advantages. (1) When constructing the formwork device 11, rear wall sections 21b are installed on both sides of the tunnel T, and beams 22 are erected between the rear wall sections 21b. Next, a top form 31 is installed on top of the beams 22. After that, another front wall section 21a is connected to the tunnel entrance side end of the rear wall section 21b, and beams 22 are erected between the front wall sections 21a. Then, the top form 31 is installed on top of the beams 22. In this way, the formwork upper body 15 is constructed. Next, the formwork upper body 15, including the entire gantry sections 12a, 12b, is raised using the side jacks 42, and the main legs 26 and traveling devices 25 are attached to the bottom of the formwork upper body 15. After that, the side jacks 42 are removed. Therefore, even if the formwork device 11 is long in the extension direction of the tunnel T, the top form 31 can be attached to the gantry segments 12a, 12b, which are the shorter halves of the formwork upper body 15 and are in the lowered position. When dismantling the formwork device 11, the work is carried out in the reverse order to that described above. Therefore, as mentioned above, even if the entire formwork device 11 is long in the extension direction of the tunnel T, there are fewer restrictions on the use of a crane, and the formwork device 11 can be constructed easily and in a short period of time. In addition, since the gantry 12 is long in the extension direction of the tunnel, the number of times concrete C is poured can be reduced. Therefore, the construction period for the tunnel can be shortened.

[0037] (2) The side jacks 42 are positioned at the ends of the front wall section 21a and the rear wall section 21b so as to be located at the four corners of the form upper body 15. This allows the form upper body 15 to be raised stably.

[0038] (3) When constructing the formwork device 11, the side jacks 42 are extended to raise the formwork upper body 15 having the top form 31, and after connecting the side form 32 to the top form 31, the invert form 33 is connected to the side form 32. In other words, the formwork upper body 15 can be raised in a lightweight state before the side form 32 and invert form 33 are connected to the top form 31. Therefore, the side jacks 42 can be driven with low power. Furthermore, when dismantling the formwork device 11, the load on the side jacks 42 is small because the formwork upper body 15 is lightweight.

[0039] (4) A loading plate P is placed on the forks F of the forklift L, and the intermediate legs 28 are placed upright on the loading plate P and then transported to the attachment position of the form upper body 15, or the intermediate legs 28 are transported from the attachment position. Therefore, the intermediate legs 28 can be transported to the bottom of the form upper body 15 in the attachment position and then easily attached to the form upper body 15 from the underside of the form upper body 15. Also, the intermediate legs 28 can be detached from the bottom of the form upper body 15 in the attachment position and removed as is. This makes it easy to attach and detach the intermediate legs 28.

[0040] (5) The top form 31 is positioned so as to straddle the connecting portion between the front wall section 21a and the rear wall section 21b. Therefore, the front wall section 21a and the rear wall section 21b are connected via the top form 31, which strengthens the connection between the front wall section 21a and the rear wall section 21b.

[0041] (Second embodiment) Next, a second embodiment of the present invention will be described with reference to FIGS. 18 to 21, focusing on the differences from the first embodiment.

[0042] In this embodiment, as shown in Figures 18 and 19, the gantry 12 is provided with front and rear gantry sections 12a, 12b that are connected to each other, as in the first embodiment. The main legs 26 and intermediate legs 28 have different shapes and configurations from those in the first embodiment. Two beams 22 are installed on the wall sections 21a, 21b of each gantry section 12a, 12b. A pair of front and rear main beams 52 and sub-beams 53 extending in the front-to-rear direction are supported on the upper surfaces of each beam 22 of each gantry section 12a, 12b via leg members 51. The front and rear main beams 52 and sub-beams 53 are connected to each other. A base beam 55 is connected to the lower surfaces of the main beams 52 and sub-beams 53 via connecting members 54.

[0043] Columns 58 are erected on the sub-beams 53. The form assembly 14 is supported by the top ends of the columns 58, the top ends of the main beams 52, and both ends of the base beams 55 on the top form 31. The formwork upper body 15 is made up of the gantry segments 12a and 12b, beams 22, main beams 52, sub-beams 53, base beams 55, columns 58, top form 31, etc. 59 denotes scaffolding.

[0044] When constructing and dismantling the formwork device 11, the main beam 52, sub-beam 53, etc. are attached and detached to each of the gantry segments 12a, 12b. As in the first embodiment, the top form 31 is attached and detached to each of the gantry segments 12a, 12b. Furthermore, as shown in Figures 20 and 21, the formwork upper body 15 is raised and lowered by the side jacks 42 attached to the formwork upper body 15 each time the top form 31 is attached and detached.

[0045] Therefore, when constructing or dismantling the formwork device 11, the same effects as those (1) to (4) of the first embodiment can be obtained. (Example of change) The present invention is not limited to the above-described two embodiments, but may be embodied in the following forms. The above-described two embodiments and the following modified examples may be combined with each other within a range that does not contradict each other.

[0046] In the above embodiment, when constructing the formwork apparatus 11, the form upper body 15 supporting the top form 31 is raised, and the side forms 32 and invert forms 33 are connected to the top form 31. When dismantling the formwork apparatus 11, the side forms 32 and invert forms 33 are removed from the top form 31. In contrast, when constructing the formwork apparatus 11, the upper portions of the side forms 32 can be connected to the top form 31 before the form upper body 15 is raised, and then the lower portions of the side forms 32 and the invert forms 33 can be connected after the formwork apparatus 11 is raised. Alternatively, when dismantling the formwork apparatus 11, before the form upper body 15 is lowered, the upper portions of the side forms 32 can be left in place, and the other portions of the side forms 32 and the invert forms 33 can be removed, and then the upper portions of the side forms 32 can be removed after the formwork apparatus 11 is lowered. Alternatively, when constructing the formwork device 11, the upper portions of the side forms 32 are connected to the top form 31 for each gantry division 12a, 12b, and after the formwork upper body 15 is raised, the lower portions of the side forms 32 and the invert forms 33 are connected.

[0047] When constructing the formwork device 11, the timing of attaching the main legs 26 and intermediate legs 28 may be different from that of the above-described embodiment. For example, when removing the side jacks 42, a temporary stand may be placed between the lower part of the side wall 21 and the ground S. Then, for example, after the installation of the form assembly 14 is completed, the main legs 26 and intermediate legs 28 may be attached in place of the temporary stand.

[0048] When dismantling the formwork device 11, the timing for removing the main legs 26 and intermediate legs 28 may be different from that of the above embodiment. For example, before connecting the side jacks 42 to the four corners of the gantry 12, a temporary platform is placed between the lower part of the side wall 21 and the ground S. Then, in this state, the main legs 26 and intermediate legs 28 are removed. After that, the side jacks 42 are connected to the four corners of the gantry 12. Then, the temporary platform is removed before the side jacks 42 are retracted.

[0049] The gantry 12 must consist of three or more gantry segments. · The side jack 42 is also provided at the middle part of the side wall 21 in the tunnel extension direction. When the side jacks 42 are extended during the construction and dismantling of the formwork device 11, the attachment and detachment of the side forms 32 and invert forms 33 below the top form 31 and the attachment and detachment of the main legs 26 and intermediate legs 28 are performed in the reverse order of the first and second embodiments.

[0050] In the above embodiment, the loading plate P is fixed to the upper surface of the fork F of the forklift L, and the intermediate legs 28 are transported to the assembly position in an upright position on the loading plate P. However, when dismantling the formwork apparatus 11, it is also possible to remove the intermediate legs 28, which have been detached from the side wall 21, from the assembly position in an upright position on the loading plate P. Furthermore, in addition to the intermediate legs 28, a loading plate can be provided on the fork of the forklift, and components other than the intermediate legs 28 used to construct the concrete formwork apparatus can be transported to the required position where they are to be assembled in an upright position on the loading plate. Alternatively, it is also possible to provide a loading plate on the fork of the forklift, and components generated in the dismantling of the concrete formwork apparatus can be removed from the assembly position in an upright position on the loading plate. [Explanation of symbols]

[0051] 11...Concrete formwork equipment 12...Gantry 12a...Gantry division body 12b...Gantry division body 14...Form assembly 15...Upper body of formwork 21…Side wall 21a...Front wall dividing body 21b...Rear wall division body 22…Beam material 25...Travel gear 26...Main legs 28...Middle leg 31...Heaven Form 32...Side Form 33...Inverted form F...fork L...Forklift P...Placement plate R...Rail S...ground T...tunnel

Claims

1. A method for constructing a concrete formwork apparatus that supports a plurality of form assemblies on a gantry that includes side walls located on both the left and right sides of a tunnel and beams installed between the upper ends of the side walls, the gantry including a plurality of gantry segments that are connected in the extension direction of the tunnel, comprising: A method for constructing a concrete formwork device, in which after constructing the gantry segment located at the end side of the gantry, a top form that forms the top of the form assembly is supported on the top of the gantry segment, another gantry segment is then constructed and connected to the existing gantry segment, and a top form is supported in the same way, and then the entire gantry segment is raised.

2. 2. The method for constructing a concrete formwork apparatus according to claim 1, wherein after the entire gantry divided body is raised, another form is connected to the lower part of the top form.

3. A method for dismantling a concrete formwork device in which a plurality of form assemblies are supported on a gantry having side walls located on both the left and right sides of a tunnel and beams erected between the upper ends of the side walls, the gantry being made up of a plurality of gantry segments connected in the extension direction of the tunnel, comprising: A method for dismantling a concrete formwork device, comprising: removing other forms below the top form of the form assembly; then lowering the gantry together with the top form; and removing the top form and disassembling the gantry segments one by one, starting from the gantry segment located at the end of the tunnel extension direction.

4. A method for dismantling a concrete formwork device as described in claim 3, wherein jacks are attached in an extended state to the four corners of the gantry, then other forms below the top form are removed, and legs attached to the bottom of the side walls are removed, and then the jacks are contracted to lower the gantry and disassemble the gantry sections.

5. A method for dismantling a concrete formwork device as described in claim 3, in which a loading plate is provided on the forks of a forklift, and components resulting from the dismantling of the concrete formwork device are placed upright on the loading plate and then removed from the position where they were assembled.

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