How to build a structure

Abstract

To provide a method for constructing a structure that can simplify construction.SOLUTION: An uneven sheet 15a, which is a sheet-like member having a plurality of convex portions 152 on the outside, is used as an inner mold. Then, hardening material 13 is sprayed and applied to an outside of the uneven sheet 15a to construct an outer shell portion of a structure. Thereafter, concrete 20 is cast and filled inside the hardening material 13 with the uneven sheet 15a left in place. As a result, a structure 1a" is constructed of the hardened material 13, the uneven sheet 15a, and the concrete 20.SELECTED DRAWING: Figure 9

Description

[Technical field]

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

[0002] When constructing concrete structures such as bridge piers and columns, the conventional procedure is to assemble the rebar, set up the formwork, pour the concrete, and then remove the formwork after curing it to the specified age.

[0003] As described above, the construction of concrete structures requires 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, with a particularly dramatic decline in the number of carpenters, and it is expected that securing carpenter manpower will become difficult in the future.

[0004] For this reason, there has been a demand in recent years for the development of simpler construction methods. One example is the SPER construction method (see, for example, Patent Document 1), in which the outer shell of a pier is formed using precast concrete panels with embedded tie bars and intermediate tie bars, and then concrete is filled inside the outer shell. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2019-148108 A Summary of the Invention [Problem to be solved by the invention]

[0006] The SPER method simplifies construction by using concrete precast panels to construct the outer shell. However, there are joints between adjacent precast panels, and if deterioration factors infiltrate through the joints, the pier may deteriorate and lose its integrity due to corrosion of the internal rebars. Therefore, it is necessary to properly treat the joints between the precast panels to prevent the infiltration of such deterioration factors, which is time-consuming to carry out.

[0007] The present invention has been made in consideration of the above problems, and has an object to provide a method for constructing a structure that can simplify construction. [Means for solving the problem]

[0008] In order to solve the above-mentioned problems, the present invention provides a method for constructing a structure by applying a hardening material to the outside of an inner form, and filling a filler inside the hardening material while leaving at least a part of the inner form, and the hardening material is applied to the outside of the inner form. Multiple A sheet-like member having a protrusion The protrusions are arranged vertically and horizontally on the outer surface of the sheet-like member, and the reinforcing material embedded in the hardening material is arranged on the outer side of the sheet-like member so as to avoid the protrusions in a side view before the hardening material is applied. The present invention relates to a method for constructing a structure.

[0009] In the present invention, the outer shell of a structure is constructed by applying a hardening material to the outside of an inner formwork. The outer shell is constructed by applying the hardening material to the inner formwork, rather than pouring (casting) the hardening material into the formwork, so that an outer formwork is not required when constructing the outer shell, and no joints are generated in the outer shell. Furthermore, at least a portion of the inner formwork is left in place and used as the structure, so that the construction of the structure as a whole can be simplified. Furthermore, the hardening material also functions as a formwork when filling the filler, and since the usual formwork work is omitted, it is possible to cope with a shortage of carpenter workers.

[0010] It is preferable to apply the hardener by spraying. In the present invention, the hardening material can be easily applied by spraying it onto the outside of the inner formwork. In this case, spraying work is required, but the hardening material can be sprayed using a normal spraying machine, and even general workers can do the work.

[0011] It is also preferable that the inner form includes a mesh member to which the hardening material is applied. This can improve the adhesion of the hardener applied to the outside of the inner formwork.

[0012] It is also desirable that the inner formwork recesses inward as it goes downward, and that the hardening material is applied thicker as it goes downward. The lateral pressure when filling the filler increases the further down it goes. Therefore, if the hardener is applied thicker the further down it goes, the rigidity that can withstand the lateral pressure can be reasonably ensured over the entire height of the hardener. At this time, by retracting the inner formwork inward as it goes downward, the outer surface of the hardener can be shaped to fit well along the vertical direction.

[0013] It is also preferable that in the step (a), a horizontal member is placed between the inner forms located at opposing positions, and both ends of the horizontal member are embedded in the hardening material. The horizontal members are passed through, for example, a lattice-like mesh reinforcement bar arranged on the outside of the inner formwork. By integrating the ends of the horizontal members with the hardening material in this manner, the horizontal members can function as separators, creating a structure that can withstand the lateral pressure that occurs during filling. Effect of the Invention

[0014] The present invention can provide a method for constructing a structure that can simplify construction. [Brief description of the drawings]

[0015] [Figure 1] A diagram showing how the structure is constructed. [Diagram 2] A diagram showing how the structure is constructed. [Diagram 3] An example in which a frame member is used as the core material 11. [Figure 4] An example of using horizontal member 18 as a separator. [Diagram 5] A diagram showing how the structure is constructed. [Figure 6] A diagram showing how the structure is constructed. [Figure 7] A diagram showing how the structure is constructed. [Figure 8] FIG. 13 is a diagram showing a structure 1a' and an example of spraying a spray material onto a lath mesh 15. [Figure 9] An example in which a concave-convex sheet 15a is used as an inner formwork. [Figure 10] A diagram showing how the structure is constructed. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

[0017] [First embodiment] 1 and 2 are diagrams showing the steps of a method for constructing a structure according to a first embodiment of the present invention. In this embodiment, a columnar structure such as a bridge pier or a pillar is to be constructed, and first, a plurality of core materials 11 are arranged in the circumferential direction of the structure as shown in FIG. 1(a).

[0018] The core material 11 is a highly rigid steel member, and H-shaped steel is used as the core material 11 in the parts that correspond to the sides of the structure's plane, with its axial direction being vertical. Adjacent H-shaped steel is placed so that the ends of the flanges face each other. Meanwhile, angle steel is used as the core material 11 in the parts that correspond to the corners of the structure's plane, with its axial direction being vertical. The angle steel is placed so that the corners of the cross section perpendicular to the axial direction face outward. Note that "outside" refers to the exterior side of the structure, and the opposite side, i.e., the center side of the structure's plane, is referred to as "inside."

[0019] 1(b), an air tube 12 is disposed between adjacent core materials 11. The air tube 12 is a cylindrical bag that is inflated by injecting air (gas). The air tube 12 is disposed so as to be in close contact with the core material 11.

[0020] As shown in FIG. 1(c), when air tubes 12 are arranged between all the adjacent core materials 11, the core materials 11 and the air tubes 12 form an inner form having a closed cross section in a square shape in plan view.

[0021] 1(d), a hardening material 13 is applied to the outside of the inner formwork. The hardening material 13 may be a cement-based material such as concrete or mortar.

[0022] In this embodiment, the hardener 13 is applied by working beside the inner form by spraying the hardener 13 onto the outside of the inner form using a spraying machine a. The state after application of the hardener 13 is shown in Fig. 2(a). The surface of the hardener 13 after spraying is smoothed by hand, for example, using a trowel.

[0023] Thereafter, the hardening material 13 is cured to harden the hardening material 13, thereby constructing the outer shell of the structure. A known hardening accelerator can be added to the hardening material 13 to accelerate hardening. By constructing the outer shell by applying the hardening material 13, the outer shell can be made into a seamless structure without joints.

[0024] 2(b), the air tubes 12 used as the inner form are removed from between the core materials 11. The air tubes 12 can be easily removed by releasing the gas therein. Meanwhile, the core materials 11 used as the inner form are left as they are.

[0025] After all the air tubes 12 have been removed, concrete 20, which is a filler, is poured and filled inside the hardening material 13, as shown in Fig. 2(c). When the concrete 20 is poured to a predetermined height, as shown in Fig. 2(d), the structure 1 is constructed, with the core material 11 and concrete 20 provided inside the shell portion made of the hardening material 13. If necessary, reinforcing bars (not shown), such as shear reinforcing bars, main bars, and distribution bars, can also be buried inside the structure 1, and in this case, the reinforcing bars should be placed at the latest before the concrete 20 is filled.

[0026] As described above, in this embodiment, the outer shell of the structure 1 is constructed by applying the hardening material 13 to the outside of the inner formwork. The outer shell is constructed by applying the hardening material 13 to the inner formwork, rather than pouring (casting) the hardening material 13 into the formwork, so that an outer formwork is not required when constructing the outer shell, and no joints are generated in the outer shell. In addition, the core material 11, which is part of the inner formwork, is left in place and used as the structure 1, so that the construction of the structure 1 as a whole can be simplified. Furthermore, the hardening material 13 also functions as a formwork when pouring the concrete 20, and since normal formwork work is omitted, it is possible to cope with a shortage of carpenter workers.

[0027] In this embodiment, the hardener 13 can be easily applied by spraying the hardener 13 onto the outside of the inner formwork. Although a spraying process is required in this embodiment, the hardener 13 can be sprayed using a normal spraying machine a, and can be performed by general workers.

[0028] In this embodiment, the steel core material 11 and the air tube 12 that expands with gas are used to easily form the inner formwork that constitutes the application surface of the hardening material 13. The air tube 12 can be easily installed and removed, is easy to transport, and does not take up much space for storage. The highly rigid core material 11 also has a reinforcing function for the hardening material 13 when the concrete 20 is poured, and the lateral pressure during pouring can be mainly borne by the core material 11. Furthermore, by leaving the core material 11 in place to construct the structure 1, the core material 11 also functions as a reinforcing material for the structure 1, and the amount of reinforcing bars inside the structure 1 can be reduced or omitted. Furthermore, by integrating the hardening material 13 and the concrete 20 through the core material 11, a highly durable structure 1 with high strength can be constructed.

[0029] However, the present invention is not limited to the above embodiment. For example, in this embodiment, the plane of the structure 1 is rectangular and the inner form has a square-shaped closed cross section, but the shape of the structure 1 is not particularly limited, and various structures 1 can be constructed by freely setting the shape of the inner form. For example, a structure having a circular plane can be constructed by using a cylindrical inner form. In addition, although a columnar structure 1 is constructed in this embodiment, it is also possible to construct, for example, a wall-shaped structure. Furthermore, depending on the shape of the structure and the construction conditions, the inner form may not have a closed cross section.

[0030] Moreover, ultra-high strength fiber reinforced concrete can also be used as the hardening material 13. Since such hardening material 13 contains steel fibers and has high tensile strength, the amount of reinforcing bars inside the structure 1 can be further reduced or eliminated.

[0031] In addition, in this embodiment, the hardener 13 is applied by spraying, but the method of applying the hardener 13 is not limited to spraying, and the hardener 13 may be applied by a plastering method. Furthermore, it is also possible to use an automatic application device (3D printer) that automatically applies the hardener 13 based on three-dimensional data of the finished shape of the outer shell part of the structure 1, which can further reduce the number of workers.

[0032] In the present embodiment, the concrete 20 is poured and filled inside the hardening material 13, but the filler filled inside the hardening material 13 is not limited to this, and may differ depending on the individual structure 1, etc.

[0033] In the present embodiment, angle steel or H-shaped steel is used as the core material 11, but other steel members may be used. For example, a truss member in which steel materials are combined in a truss shape, or a frame member in which steel materials are combined in a ladder shape may be used as the core material 11.

[0034] 3(a), the frame member has a highly rigid ladder-like configuration formed by connecting a pair of vertical frame portions 111 with connecting portions 112. The plane of the vertical frame portion 111 is concave-shaped, and a folded portion 111a that is folded back in a direction away from the concave is provided at the portion corresponding to the upper end of the concave.

[0035] The pair of vertical frame parts 111 are arranged back to back with the bottom sides of the concave shapes. The connecting parts 112 are provided vertically with a gap between them, and connect the bottom sides of the vertical frame parts 111. The bottom sides of the vertical frame parts 111 are provided with a plurality of openings 114 with a gap between them vertically.

[0036] Adjacent frame members are arranged so that the folded portions 111a face each other, and an inner formwork can be formed in the same manner as above by placing an air tube 12 between the adjacent frame members as shown by the arrows in Fig. 3(a), and the outer shell of the structure can be constructed by applying hardening material 13 to the outside of the inner formwork. Fig. 3(b) is a plan view showing the state after hardening material 13 has been applied to the outside of the inner formwork in the case where the above frame members are used as the core material 11 instead of the H-shaped steel.

[0037] Thereafter, the air tube 12 is removed in the same manner as above, and concrete 20 is poured inside the hardening material 13 to construct a structure. The frame members are high-rigidity, lightweight steel members, and can reasonably ensure the rigidity required to withstand the lateral pressure applied when pouring the concrete 20. In addition, since the frame members are constructed by combining steel members in a ladder shape, they are highly integrated with the filler material, and can be effective as a reinforcing material for the structure 1. It is to be noted that the use of frame members for formwork support that are commercially available as standard products can be expected to reduce the cost of steel materials.

[0038] 4(a), a horizontal member 18 may be placed between opposing inner forms with both ends 181 protruding from the inner forms and embedded and integrated into the hardening material 13. This allows the horizontal member 18 to be used as a separator, resulting in a structure that can withstand the lateral pressure when pouring the concrete 20. The horizontal member 18 is placed before the hardening material 13 is applied.

[0039] The horizontal member 18 can be, for example, a reinforcing bar such as the above-mentioned shear reinforcing bar, and by arranging the horizontal member 18 on reinforcing materials (not shown) of the structure, including other reinforcing bars, the resistance to lateral pressure during pouring of the concrete 20 is improved. However, the horizontal member 18 is not limited to this. In the example of Fig. 4(a), a frame member is used as the core material 11, and by arranging the horizontal member 18 through the opening 114 (see Fig. 3(a)), interference with the air tube 12 can be avoided.

[0040] Furthermore, as shown in Fig. 4(b), an anchoring portion may be provided by expanding the diameter of the end portion 181 of the horizontal member 18, thereby increasing the anchoring force to the hardener 13. Also, as shown in Fig. 4(c), a lattice-shaped mesh reinforcement 182 may be provided near the anchoring portion to reinforce the hardener 13 near the anchoring portion. In addition, as shown in Fig. 4(d), the hardener 13 near the anchoring portion may be applied thicker than other portions to increase the anchoring effect. In this embodiment, the hardener 13 is applied by application, so the thickness of the hardener 13 can be easily increased.

[0041] Hereinafter, other examples of the present invention will be described as the second and third embodiments. Each embodiment will be described in terms of differences from the previously described embodiments, and similar points will be denoted by the same reference numerals in the drawings and will not be described. In addition, the configurations described in each embodiment, including the first embodiment, can be combined as necessary.

[0042] [Second embodiment] 5 to 7 are diagrams showing a method for constructing a structure according to a second embodiment of the present invention. The second embodiment is an example in which the configuration of the inner formwork to which the hardening material 13 is applied is different.

[0043] That is, in this embodiment, as shown in Fig. 5(a), a lath net 15 is supported by vertical supports 14 provided at the corners of the structure in plan view, and the lath net 15 is arranged so as to have a closed cross section in a square shape in plan view, forming an inner formwork for applying the hardening agent 13. Mesh reinforcement 17 is provided on the outside of the lath net 15, and a spacer 16 is placed between the lath net 15 and the mesh reinforcement 17. The support materials 14 can be, for example, reinforcing bars such as the main reinforcement bars described above, but are not limited to these.

[0044] As shown in Fig. 5(b), the lath net 15 is a steel net member. The mesh reinforcement 17 is a steel net member having larger mesh than the lath net 15, and is formed by combining vertical and horizontal reinforcing bars in a lattice pattern.

[0045] In this embodiment, the outer shell of the structure is constructed by applying hardening material 13 to the outside of the lath net 15 (inner formwork) as shown in Fig. 6(a). As shown in Fig. 6(b), the hardening material 13 is applied by spraying, and the sprayed hardening material 13 is held by the lath net 15. Mesh reinforcement 17 is embedded in the hardening material 13 to reinforce it.

[0046] After the hardening material 13 hardens, concrete 20 is poured and filled inside the hardening material 13 to construct the structure 1a, as shown in Fig. 7. In this embodiment, the lath mesh 15 used as the inner formwork is left as it is and is embedded in the structure 1a.

[0047] In the second embodiment, the hardening material 13 is applied to the outside of the lath mesh 15, and then the lath mesh 15 is left in place and concrete 20 is poured inside the hardening material 13, so that the construction of the structure 1a can be easily carried out in the same manner as in the first embodiment.

[0048] In addition, by using the lath net 15 as an inner formwork when applying the hardening material 13, the adhesion of the hardening material 13 is improved. The adhesion between the lath net 15 and the concrete 20 is also improved, and a high-strength structure 1a in which the hardening material 13 and the concrete 20 are integrated through the lath net 15 can be constructed.

[0049] Moreover, by embedding mesh reinforcement 17 in hardening material 13, the lateral pressure when pouring concrete 20 is also borne by mesh reinforcement 17, reducing the tensile stress generated in hardening material 13. Furthermore, by reinforcing hardening material 13 in the outer shell portion of structure 1a with mesh reinforcement 17, the durability of structure 1a can be improved and a reduction in reinforcing bars inside structure 1a can be expected.

[0050] As a method of reinforcing the hardening material 13, in addition to burying reinforcing materials such as mesh bars 17, adjusting the shape and thickness of the hardening material 13 is also effective. The shape of the hardening material 13 can vary depending on the shape of the inner formwork, and for example, as shown in the structure 1a' in Fig. 8(a), by providing a vertical groove 151 recessed inward in the lath mesh 15, a convex rib is formed on the inside of the hardening material 13, which improves the rigidity of the hardening material 13 and also improves the unity between the hardening material 13 and the concrete 20 inside it.

[0051] Also, before applying the hardener 13, a spray material b such as resin may be sprayed onto the lath net 15 as shown in Fig. 8(b). This makes the mesh of the lath net 15 smaller, preventing the hardener 13 from slipping through the lath net 15 when applying it, and also reinforces the lath net 15 itself, improving its rigidity.

[0052] Moreover, mesh reinforcement 17 may be used instead of the lath net 15, and as shown in Fig. 9(a), a concave-convex sheet 15a may be used as an inner formwork when applying the hardening material 13. The concave-convex sheet 15a is a sheet-like member having a plurality of convex portions 152 on the outside, and is made of a material having rigidity such as mortar, resin concrete, or resin. The convex portions 152 are arranged in a large number vertically and horizontally on the outside of the concave-convex sheet 15a.

[0053] FIG. 9(a) shows the state in which the outer shell of the structure has been constructed by applying hardening material 13 to the outside of the embossed sheet 15a. After this, concrete 20 is poured and filled inside the hardening material 13 to construct the structure 1a'' shown in FIG. 9(b).

[0054] As with the lath net 15, the use of the uneven sheet 15a also improves the adhesion of the hardening material 13 due to the numerous protrusions 152. A reinforcing material can be embedded in the hardening material 13. In this case, steel materials 31 such as reinforcing bars may be placed outside the uneven sheet 15a before the hardening material 13 is applied, as shown in FIG. 9(c). In the example of FIG. 9(c), the steel materials 31 are placed obliquely outside the uneven sheet 15a so as to avoid the protrusions 152. In addition, protrusions may be provided on the inside of the uneven sheet 15a in the same manner as on the outside, to enhance the unity between the hardening material 13 and the concrete 20 via the uneven sheet 15a.

[0055] [Third embodiment] 10 is a diagram showing a method for constructing a structure according to a third embodiment of the present invention. The third embodiment is an example in which the coating thickness of the hardening material 13 is changed depending on the height.

[0056] That is, in this embodiment, as shown in Fig. 10(a), the shape of the inner form 19 to which the hardening material is applied is set so that the cross-sectional area of ​​the inner space becomes smaller as it goes downward, with the inner form 19 having a closed cross-section in a square shape in a plan view.

[0057] In this embodiment, the outer shell of the structure is constructed by applying the hardener 13 to the outside of the inner formwork 19, but as shown in Fig. 10(b), the hardener 13 is applied thicker the further downwards, with the top end having the smallest thickness Tt and the bottom end having the largest thickness Tb. The shape of the inner formwork 19 is recessed inward in accordance with the change in the applied thickness described above, and as a result, the outer surface of the hardener 13 is formed along the vertical direction.

[0058] After applying the hardening material 13 in this manner, the structure 1b is constructed by pouring concrete 20 inside the hardening material 13 as shown in Fig. 10(c). In this embodiment, the inner formwork 19 is left as it is.

[0059] In the third embodiment, the hardening material 13 is applied to the outside of the inner formwork 19, and then the inner formwork 19 is left in place and concrete 20 is poured inside the hardening material 13, so that construction of the structure 1b can be easily carried out, as in the first embodiment.

[0060] In this embodiment, the hardener 13 is applied thicker downwards, because the lateral pressure during pouring of the concrete 20 increases downwards. That is, if the hardener 13 is applied thicker downwards and the thickness of the hardener 13 is set to match the distribution of the lateral pressure, the rigidity capable of withstanding the lateral pressure can be reasonably ensured over the entire height of the hardener 13. In this embodiment, the inner formwork 19 is shaped to recede inwardly downwards in accordance with the change in thickness of the hardener 13, so that the outer surface of the hardener 13 can be shaped to fit well along the vertical direction.

[0061] 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]

[0062] 1, 1a, 1a', 1a", 1b: Structure 11: Core material 12: Air tube 13: Hardening material 15: Las Vegas 15a: Textured sheet 18: Horizontal material 19: Inner formwork 20: Concrete

Claims

1. (a) applying a hardener to the outside of the inner formwork; (b) filling a filler material inside the hardened material while leaving at least a part of the inner form; A structure is constructed by the hardening material, at least a part of the inner form, and the filling material, The inner form includes a sheet-like member having a plurality of protruding portions on an outer side thereof, the protruding portions being arranged vertically and horizontally on the outer surface of the sheet-like member, A method for constructing a structure, characterized in that a reinforcing material embedded in the hardening material is positioned outside the sheet-like member so as to avoid the convex portion in a side view before the hardening material is applied.

2. 2. The method for constructing a structure according to claim 1, wherein the hardening material is applied by spraying.

3. The inner formwork recedes inward as it goes downward, 3. The method for constructing a structure according to claim 1, wherein the hardener is applied thicker downward.

4. A method for constructing a structure as described in any one of claims 1 to 3, characterized in that in step (a), a horizontal member is placed between the inner formworks in opposing positions, and both ends of the horizontal member are embedded in the hardening material.

5. A method for constructing a structure as described in claim 4, characterized in that the horizontal members are passed through lattice-shaped mesh reinforcement arranged on the outside of the inner formwork.

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