Method of constructing formwork and structure

Abstract

To provide a formwork or the like capable of suitably suppressing deflection when a hardening material is applied.SOLUTION: An inner formwork 1 is used when constructing a structure 10. The inner formwork 1 has a mesh material 4, which is a flexible, planar member to which a hardening material 5 is applied, and a formwork reinforcing material 3 for reinforcing the mesh material 4 and increasing the out-of-plane rigidity of the mesh material 4. After the hardening material 5 is applied to the mesh material 4 to form the outer shell of the structure 10, concrete 6 is poured inside the outer shell, thereby constructing the structure 10.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a formwork and a method for constructing a structure using the formwork. [Background technology]

[0002] When constructing a concrete structure such as a wall, conventionally, it is common to assemble reinforcing bars, assemble forms, pour concrete, and then remove the forms after curing the concrete to a specified age.

[0003] As described above, the construction of concrete structures involves a mixture of multiple types of work, making the work complicated. In addition, there has been a tendency in recent years to be a shortage of skilled construction workers, and the number of carpenters who are responsible for assembling and dismantling formwork has decreased significantly, so it is expected that it will become difficult to secure carpenter personnel in the future.

[0004] For this reason, in recent years, there has been a demand for the development of simpler construction methods.As an example, Patent Document 1 discloses a construction method in which a hardening material such as mortar is applied to an inner formwork by a spraying method to form an outer shell, and then concrete is poured inside the outer shell to construct a structure. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2022-181299 A Summary of the Invention [Problem to be solved by the invention]

[0006] According to the above method, the construction of the structure can be simplified and the shortage of workers can be addressed. In addition, in Patent Document 1, the end of the tensile member located inside the outer shell is fixed to the outer shell with a fixing jig, so that the tensile member can resist the lateral pressure when pouring concrete inside the outer shell.

[0007] However, the above method uses flexible wire lath as the inner formwork (core material) when spraying the hardener. Although this method is easy to work with, the wire lath can bend inward due to the spray pressure or weight of the hardener, which can affect the finished shape and can result in wasted material.

[0008] In addition, the hardening material may pass through the mesh of the lath net, resulting in waste of material. Although it is possible to prevent the hardening material from passing through by using a fine mesh material instead of the lath net, most such mesh materials have low rigidity and cannot suppress the above-mentioned deflection.

[0009] The present invention has been made in consideration of the above problems, and has an object to provide a formwork or the like that can suitably suppress deflection when a hardening material is applied. [Means for solving the problem]

[0010] The first invention for solving the above-mentioned problems is a formwork used when constructing a structure, characterized in that it has a flexible planar member to which a hardening agent is applied, and a formwork reinforcement material for reinforcing the planar member and increasing the out-of-plane rigidity of the planar member.

[0011] In the present invention, when applying a hardening material to a flexible planar member such as a lath net during construction of a structure, the planar member is reinforced with a formwork reinforcement material. This makes it possible to suppress bending during application of the hardening material and maintain the planar state of the planar member, and also makes it possible to use a member with lower rigidity as the planar member.

[0012] The planar member is, for example, a mesh material. The formwork reinforcing member is, for example, a lattice-like arrangement of wires, and the openings of the lattice are larger than the meshes of the mesh material. In the present invention, a mesh material that is easy to process and has high workability can be used as the planar member, and a member with finer mesh and lower rigidity can be used by using a formwork reinforcement material. On the other hand, the formwork reinforcement material does not need to have a function to prevent the hardening material from passing through, and can be a lattice-like member with openings larger than the mesh of the mesh material.

[0013] The planar member may be a water-soluble sheet. This allows the planar member to be dissolved and eliminated by watering and curing the hardening material, and when concrete is poured inside the hardening material, which serves as the outer shell, the hardening material and concrete can be integrated.

[0014] It is also desirable for the formwork reinforcement to be foldable. This allows the formwork reinforcement to be stored and transported in a folded state, improving workability.

[0015] The second invention is a method for constructing a structure using the formwork of the first invention, characterized in that a structure is constructed using the hardener and the filler by the steps of applying a hardener to the planar member and filling the inside of the hardener with a filler. The second invention is a method for constructing a structure using the formwork of the first invention. Effect of the Invention

[0016] According to the present invention, it is possible to provide a formwork or the like that can suitably suppress deflection when a hardening material is applied. [Brief description of the drawings]

[0017] [Figure 1] FIG. 2 shows a method for constructing the structure 10. [Diagram 2] A diagram showing mesh materials 4, 4'. [Diagram 3] A diagram showing formwork reinforcement material 3. [Figure 4] An example of how to fix mesh material 4. [Diagram 5]A diagram showing sheets 4a, 4b, and 4c. [Figure 6] A diagram showing formwork reinforcement 3'. [Figure 7] A diagram showing formwork reinforcement material 3a. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

[0019] Fig. 1 is a diagram showing each process when constructing a structure 10 using an inner form 1 according to an embodiment of the form of the present invention. In this embodiment, the structure 10 is wall-shaped, and each drawing in Fig. 1 shows only a part corresponding to one side in the wall thickness direction. However, the structure 10 is not particularly limited, and can be, for example, columnar.

[0020] In this embodiment, first, as shown in Fig. 1(a), main reinforcement bars 21, distribution bars 22, shear reinforcement bars 23, etc. are arranged as reinforcing materials for the structure 10. Note that reference numeral 231 denotes an anchor plate provided at the end of the shear reinforcement bar 23.

[0021] Next, as shown in Fig. 1(b), a formwork reinforcement material 3 is placed on the outside of the reinforcement material of the above-mentioned structure 10. Then, as shown in Fig. 1(c), a mesh material 4 is attached to the outside of the formwork reinforcement material 3, and as shown in Fig. 1(d), a hardening material 5 is sprayed onto the outside of the mesh material 4.

[0022] The hardening material 5 in this embodiment is mortar, and for example, by using high-strength mortar, the durability of the structure 10 can be increased. However, the hardening material 5 is not limited to this, and cement-based materials other than mortar, such as concrete, can also be used. For example, ultra-high-strength fiber-reinforced concrete can be used as the hardening material 5, and the amount of reinforcing material in the structure 10 can be reduced due to the bending toughness achieved by mixing steel fibers with high tensile strength.

[0023] In this embodiment, as in Patent Document 1, the hardener 5 is sprayed onto the outside of the mesh material 4 using a spraying machine, so that the hardener 5 is applied by working on the outside of the mesh material 4. The surface of the hardener 5 after spraying is smoothed, for example, by manual trowel finishing. Here, "outside" refers to the exterior side of the structure 10, which corresponds to the right side of each diagram in FIG. 1. The interior side of the structure 10 is referred to as "inside", which corresponds to the left side of each diagram in FIG. 1.

[0024] As shown in Fig. 1(c), the form reinforcing material 3 and the mesh material 4 constitute an inner form 1 to which a hardening material 5 is applied. The inner form 1 corresponds to the form of the present invention.

[0025] Fig. 2(a) is a diagram showing a mesh material 4. The mesh material 4 is a member onto which the hardening agent 5 is applied by spraying, and serves to fix the hardening agent 5. A planar member that is flexible, thin, and easy to process is used as the mesh material 4. Here, "flexible" refers to the elasticity or flexibility of the member, or the ability of the member to deform due to its deformation mechanism, etc.

[0026] The mesh of the mesh material 4 is of a size that prevents the hardening material 5 from passing through. For example, the size of the mesh is determined so that no gaps are formed that exceed the dimensions (e.g., 5 mm) of the fine aggregate in the mortar used as the hardening material 5. The shape of the mesh is not particularly limited, and may be, for example, a quadrangle such as a diamond or other polygonal shape. Also, as shown in Fig. 2(b), the cross section of the thickness direction of the mesh material 4' may be blind-shaped, inclined downward toward the outside (corresponding to the right side of Fig. 2(b)).

[0027] The material for the mesh material 4 may be iron, glass fiber, polypropylene, FRP (fiber reinforced plastic), etc., but is not particularly limited as long as it is alkali resistant and does not adversely affect the performance of the structure 10.

[0028] 3 is a diagram showing the formwork reinforcement material 3. The formwork reinforcement material 3 is a member for reinforcing the mesh material 4 to increase its out-of-plane rigidity so that the mesh material 4 does not deform due to the spray pressure of the hardening material 5 or the weight of the hardening material 5 and can stand on its own while maintaining a flat state, and is different from the reinforcing materials of the structure 10 (such as the main reinforcement bars 21 described above).

[0029] In the example of Fig. 3, the formwork reinforcement 3 is formed by arranging wires 31, 32 such as reinforcing bars vertically and horizontally in a lattice pattern, with rectangular openings. The thickness and spacing of the wires 31, 32 are determined so as to satisfy the above-mentioned purpose of the formwork reinforcement 3, and are not particularly limited. For example, in this embodiment, the formwork reinforcement 3 is made of mesh reinforcement, and the openings of the lattice have a larger area than the mesh (opening) of the mesh material 4, but thin wires 31, 32 such as iron wires may be combined in a lattice pattern with narrower spacing. It is not necessarily necessary to use thick reinforcing bars in order to withstand the sprayed thickness of the hardening material 5.

[0030] The material of the formwork reinforcement 3 is not particularly limited as long as it is alkali resistant and does not adversely affect the performance of the structure 10, and in addition to reinforcing bars and iron wires, FRP and the like can be used. The shape of the opening is also not particularly limited, and it can be, for example, tortoiseshell-shaped.

[0031] The mesh material 4 and the formwork reinforcement 3 can be fixed easily. For example, the mesh material 4 and the formwork reinforcement 3 may be tied together, or they may be fixed together using a C-shaped ring or a hog ring. Furthermore, if both are made of metal or thermoplastic resin, they can be fixed together by welding or fusion. Alternatively, as shown in Fig. 4, the mesh material 4 can be fixed by being sandwiched between the vertical and horizontal wires 31 and 32 of the formwork reinforcement 3.

[0032] In this embodiment, the mesh material 4 and the formwork reinforcement material 3 are fixed on-site, but they may be fixed in advance at a factory or the like by the above-mentioned methods and transported to the site for use. This eliminates on-site work and improves workability. Also, a spacer (not shown) may be provided between the formwork reinforcement material 3 and the reinforcement material of the structure 10, and the inner formwork 1 may be formed with a gap between the reinforcement material and the inner formwork 1.

[0033] As shown in FIG. 1(d), the hardening material 5 is applied, and then curing is performed to harden the hardening material 5, thereby constructing the outer shell of the structure 10. A known hardening accelerator can be added to the hardening material 5 to accelerate hardening. In this embodiment, as in the above-mentioned Patent Document 1, the end of the tensile material located inside the outer shell is fixed to the outer shell, so that when concrete is poured inside the outer shell in a later process, the tensile material can resist the lateral pressure of the concrete. In this case, the end of the tensile material needs to be inserted through the mesh material 4, but in this embodiment, since the mesh material 4 is thin, holes can be easily drilled.

[0034] 1(e), concrete 6, which is a filler, is poured inside the outer shell made of the hardening material 5 to fill the space, thereby constructing the structure 10. Note that in this embodiment, the inner formwork 1 is embedded in the structure 10 without being removed, but depending on the arrangement of the main reinforcement bars 21, etc., it is also possible to remove the inner formwork 1 and then pour the concrete 6 to construct the structure 10.

[0035] As described above, in this embodiment, when the hardening material 5 is applied to the mesh material 4 during construction of the structure 10, the mesh material 4 is reinforced by the formwork reinforcement material 3. This makes it possible to suppress bending during application of the hardening material 5 and maintain the flat state of the mesh material 4.

[0036] In addition, the mesh material 4 is easy to process and has high workability, and in this embodiment, by reinforcing the mesh material 4 with the formwork reinforcement material 3, it becomes possible to use a finer mesh and lower rigidity material as the mesh material 4. On the other hand, since the formwork reinforcement material 3 does not need to have the function of preventing the hardening material 5 from passing through, a material with openings larger than the mesh of the mesh material 4 can be used.

[0037] However, the present invention is not limited to the above embodiment. For example, in this embodiment, the hardening material 5 is sprayed onto the mesh material 4, but the target of the hardening material 5 may be a planar member that is deformable (flexible) due to the elasticity or flexibility of the member or the deformation mechanism of the member, as described above, and a water-soluble sheet 4a without an opening may be attached to the formwork reinforcement member 3 as shown in FIG. 5(a). In this case, the sheet 4a dissolves and disappears due to water spray curing of the hardening material 5, so that the hardening material 5 and the concrete 6 can be easily integrated when concrete 6 is poured inside the hardening material 5 as the outer shell. For example, a PVA (polyvinyl alcohol) film can be used as the water-soluble sheet 4a.

[0038] Also, a water-soluble sheet 4a can be used in combination with the mesh material 4 as an auxiliary to the mesh material 4. That is, even if the mesh size of the mesh material 4 is made small, it is difficult to completely prevent the hardening material 5 from passing through, and the water-soluble sheet 4a may be difficult to fix the hardening material 5 due to the film properties, but by sandwiching the water-soluble sheet 4a between the mesh material 4 and the formwork reinforcement material 3, the hardening material 5 can be fixed securely while increasing the effect of preventing the hardening material 5 from passing through. Since the sheet 4a dissolves and disappears due to watering curing of the hardening material 5, the integrity of the hardening material 5 and the concrete 6 becomes the same as when only the mesh material 4 is used.

[0039] Also, as shown in Fig. 5(b) in cross section in the thickness direction, a napped sheet 4b (without openings) may be used, and as shown in Fig. 5(c) in cross section in the thickness direction, a sheet 4c (without openings) with unevenness on both sides may be used. This allows the hardening material 5 to be integrated with the concrete 6 via these sheets 4b and 4c when concrete 6 is poured inside the hardening material 5 as an outer shell. By providing a chemically reactive group on the surface of the napped sheet 4b, it is also possible to chemically bond with the hardening material 5 and concrete 6.

[0040] Furthermore, the formwork reinforcement 3 can be made flexible by its deformation mechanism, which improves workability. For example, as shown in formwork reinforcement 3' in Fig. 6(a), a foldable configuration may be used in which some of the vertically arranged wires 31 serve as hinges and the horizontally oriented wires 32 can be rotated as shown by arrows a and b in Fig. 6(b). This allows the formwork reinforcement 3' to be stored or transported in a folded state, and then unfolded and installed at the site, facilitating work. It should be noted that the horizontal wires 32 can also be used as hinges, not limited to the vertical wires 31.

[0041] As shown in Fig. 7, a wire mesh (mesh member) having a diamond-shaped or tortoise-shell-shaped lattice that can be deformed by the elasticity of the member may be used as the foldable formwork reinforcement 3a. In this case, the formwork reinforcement 3a can be folded without providing the above-mentioned mechanism. Instead of making the formwork reinforcement 3a foldable, it may be made so that it can be wound up in a roll. Also, a mesh member 4 may be fixed to the formwork reinforcement 3', 3a in advance at a factory or the like so that the mesh member 4 can deform in accordance with the deformation of the formwork reinforcement 3', 3a.

[0042] In addition, in this embodiment, the hardener 5 is applied by spraying, but the method of applying the hardener 5 is not limited to spraying, and the hardener 5 may be applied by a plastering method or the like. Furthermore, it is also possible to use an automatic application device (3D printer) that automatically applies the hardener 5 based on three-dimensional data of the finished shape of the outer shell of the structure 10, thereby further reducing the number of workers.

[0043] In this embodiment, concrete 6 is poured and filled inside the shell made of hardening material 5, but the filler filled inside the shell is not limited to this, and may differ depending on the individual structure 10, etc.

[0044] Furthermore, in parallel with the installation of reinforcing materials such as main reinforcement 21, distribution reinforcement 22, and shear reinforcement 23 of structure 10, a hardening material 5 may be applied to the outside of mesh material 4 to which formwork reinforcement 3 is attached in a separate location to form an outer shell. After that, the outer shell can be attached to the outside of the reinforcing materials described above, and concrete 6 can be poured inside to construct structure 10. In this example, the construction period can be shortened by simultaneously carrying out the reinforcing bar arrangement work for structure 10 and the work of forming the outer shell.

[0045] In this embodiment, reinforcing bars such as the main bars 21 are used as reinforcing materials for the structure 10, but as reinforcing materials for the structure 10, shaped steel such as H-shaped steel or steel plates may also be used.

[0046] Although the preferred embodiment of the present invention has been described above with reference to the accompanying drawings, the present invention is not limited to the above examples. It is clear that a person skilled in the art can come up with various modified or altered examples within the scope of the technical ideas disclosed in this application, and it is understood that these also naturally belong to the technical scope of the present invention. [Explanation of symbols]

[0047] 1: Inner formwork 3, 3', 3a: Formwork reinforcement 4, 4': Net material 4a, 4b, 4c: Seats 5: Hardening material 6: Concrete 10: Structure

Claims

1. A formwork used in constructing a structure, a flexible planar member onto which a curing agent is applied; A formwork reinforcement material for reinforcing the planar member and increasing the out-of-plane rigidity of the planar member; A formwork characterized by having:

2. The formwork according to claim 1, wherein the planar member is a mesh material.

3. The formwork reinforcement material is formed by arranging wires in a lattice pattern, 3. A formwork according to claim 2, wherein the openings of the grid are larger than the mesh of the mesh material.

4. 2. The formwork according to claim 1, wherein the planar member is a water-soluble sheet.

5. 2. The formwork of claim 1, wherein the formwork reinforcement is collapsible.

6. A method for constructing a structure using the formwork according to claim 1, comprising the steps of: applying a hardening material to the planar member; Filling the inside of the hardening material with a filler; A method for constructing a structure, comprising constructing a structure using the hardener and the filler.

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