Floor slab forming method

Abstract

To provide a floor slab forming method that suppresses occurrence of steps and constructs an openable portion that efficiently blocks a through hole.SOLUTION: A floor slab 11 having a through hole 11h formed therein is constructed. An opening surface of the through hole 11h is divided into a plurality of regions each having a predetermined size or less by small beams 21, 22 and a PC board receiving member 25. Next, concrete is poured into each area of the through hole 11h that is partitioned to correspond to the small beams 21, 22 and the PC board receiving member 25, to form an openable portion 20 that blocks the through hole, in the floor slab 11.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to a method for forming a floor slab having an openable portion. [Background technology]

[0002] Through holes (openings) formed in the floors of buildings are sometimes blocked with concrete blocks (see, for example, Patent Document 1). This document describes how a bottom plate made of PCa (precast) concrete is placed inside the opening frame, mesh reinforcement is placed on top of this floor plate, and then concrete is poured to block the through holes.

[0003] On the other hand, in a building with multiple floors, a single tenant may rent several consecutive floors. In this case, there is a need to provide an internal staircase that directly connects the upper and lower floors of the different areas rented by the tenant. In order to meet such needs, a building may be constructed in which a through hole for providing the internal staircase is formed in advance in the floor slab, and then this through hole is blocked with a concrete panel or the like to provide an openable portion. When providing the internal staircase, the blocking concrete panel is removed to expose the through hole, and then the internal staircase is constructed in this through hole. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 7-62779 Summary of the Invention [Problem to be solved by the invention]

[0005] As shown in Patent Document 1, it is possible to block the through-hole formed to provide an internal staircase with multiple precast (PCa) concrete panels formed in a factory or the like. However, when using these PCa concrete panels, it takes time to adjust them to be flush with the surroundings of the through-hole. In addition, since the PCa concrete panels are transported from the factory, safety management is required until the through-hole is blocked. [Means for solving the problem]

[0006] A method of forming a floor slab that solves the above-mentioned problems is a method of forming a floor slab of a building, which involves creating a through hole in the floor slab, dividing the opening surface of the through hole into a plurality of areas of a predetermined size or less using support members, and pouring concrete into each of the areas partitioned in the through hole to correspond to the support members, thereby forming an openable portion in the floor slab that blocks the through hole. Effect of the Invention

[0007] According to the present invention, it is possible to suppress the occurrence of a step and to construct an openable portion that efficiently blocks the through hole. [Brief description of the drawings]

[0008] [Figure 1] FIG. 2 is a conceptual diagram illustrating the configuration of a floor slab provided with an openable portion according to an embodiment. [Diagram 2] 1 is a plan view illustrating the configuration of an openable portion in which a plurality of concrete blocks are arranged to block a through hole in an embodiment. FIG. [Diagram 3] 3 is a cross-sectional view taken along line 3-3 in FIG. 2. [Figure 4] 4 is a cross-sectional view taken along line 4-4 in FIG. 2. [Diagram 5] 5 is a cross-sectional view taken along line 5-5 in FIG. 2. [Figure 6] 4 is a flowchart illustrating a process for blocking a through hole in the embodiment. [Figure 7]1 is a plan view illustrating the state of a main part of an openable portion immediately before pouring concrete in an embodiment. FIG. [Figure 8] FIG. 2 is a plan view illustrating the state of the main parts of the openable portion after concrete is poured in a first pouring stage and before concrete is poured in a second pouring stage in an embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment of a method for forming a floor slab will be described with reference to Figures 1 to 8. In this embodiment, a method for forming a floor slab having an openable portion by closing a through hole after a through hole is formed in the floor slab in a building having multiple floors will be described. This openable portion is provided so that an internal staircase that connects adjacent floors above and below can be provided later.

[0010] Fig. 1 is a schematic diagram showing continuous upper and lower floors in a building as an architectural structure. As shown in Fig. 1, an openable portion 20, which is a rectangular parallelepiped area, is provided in the floor slab 11 of the upper floor. This openable portion 20 is formed by closing a through hole 11h using a plurality of concrete blocks described later. This openable portion 20 is opened when an internal staircase 18 is formed to connect the floor slab 11 and the floor slab 17 of the floor immediately below, and is closed when the internal staircase 18 is not formed.

[0011] (Configuration of the openable portion 20) Fig. 2 is a top view of the openable portion 20 of the floor slab 11. Figs. 3 to 5 are cross-sectional views taken along lines 3-3, 4-4, and 5-5 in Fig. 2, respectively. Here, FL shown in Figs. 3 to 5 is floor level.

[0012] As shown in FIG. 2, H-shaped steel girders 12 are arranged on the floor slab 11 in each of the four directions so as to surround the peripheral portion of the openable portion 20. The openable portion 20 of the floor slab 11 has a through hole 11h formed in the floor slab 11. In this embodiment, the through hole 11h has a size of about 7.2 m in width and about 4.1 m in length. Then, the small beams 21 arranged in two rows spaced apart and the small beams 22 arranged in one row are attached to the girder 12 so as to divide the opening surface of the through hole 11h. The small beams 21 are attached to the girder 12 arranged above and below the openable portion 20 in FIG. 2 and extend in the vertical direction in FIG. 2. The small beams 22 are attached to the girder 12 arranged on the left and right of the openable portion 20 in FIG. 2 and extend in the horizontal direction in FIG. 2 so as to be perpendicular to the small beams 21. Furthermore, one end of three rows of PC board support members 25 made of channel steel is fixed to the small beam 22. The other end of each PC board support member 25 is fixed to the girder 12 arranged above and below in FIG. 2. Here, the small beams 21, 22 and the PC board receiving member 25 correspond to support members for dividing the opening surface (space) of the through hole 11h.

[0013] A plurality of rectangular parallelepiped shaped concrete blocks 31a, 31b, 32a, 32b, 33a, 33b, 34a, 34b, 35a, 35b, 36a, and 36b are arranged inside the through hole 11h with a sealing member 38 interposed therebetween.

[0014] The concrete blocks (31a to 36b) are arranged in a plurality of rows (2 rows x 6 blocks) of areas defined in correspondence with the small beams 21, 22 and the PC board receiving members 25 described above. The concrete blocks (31a to 36b) are adjacent to each other via sealing members 39. In this embodiment, the sealing members 39 are arranged in a lattice pattern. The sealing members 38 and 39 are made of a known sealant.

[0015] 3, a thin mounting plate 13 is fixed to the upper flange 12f of the girder 12 so as to protrude toward the through hole 11h of the openable portion 20. A sealing member 38 is located above the inner peripheral edge of the through hole 11h.

[0016] 4, ends of adjacent concrete blocks (35a, 35b) are placed on the upper flange 22f of the minor beam 22. A sealing member 39 is located above the web 22w of the minor beam 22.

[0017] 5, the small beam 22 is joined to the small beam 21 via the mounting plate 23. Furthermore, a PC board receiving member 25 is fixed to the small beam 22. A sealing member 39 is located above the PC board receiving member 25 and above the web 21w of the small beam 21.

[0018] The ends of the concrete blocks (31a to 36b) are supported by the mounting plate 13 (Fig. 3) of the main girder 12, the upper flange 22f (Fig. 4) of the secondary girder 22, and the PC board support member 25 (Fig. 5). Furthermore, rubber sheets 13s, 22s are fixed to the lower surfaces of the mounting plate 13 and the upper flange 22f, respectively, so as to reach the lower surfaces of the ends of the concrete blocks (31a to 36b). Furthermore, bolts 15 that screw into inserts 14 embedded only in the short sides of the concrete blocks (31a to 36b) pass through the rubber sheets 13s, 22s.

[0019] (Concrete block structure) Each concrete block (31a to 36b) shown in FIG. 2 has a substantially identical rectangular shape and has a size (approximately 2 m×approximately 1.2 m×approximately 20 cm) and weight (approximately 1 t) that allows it to be transported using an elevator or the like within a building. Furthermore, hanging bolts B1 are provided near each of the four corners on the upper surface of each of the concrete blocks (31a to 36b).

[0020] As shown in FIGS. 3 to 5, each of the concrete blocks (31a to 36b) is formed by embedding a plurality of reinforcing bars (45, 46) and a plurality of distribution bars 48 of the lower deck 40 (described later) in concrete C1.

[0021] The fell deck 40 is a member that integrates a deck plate 41, an L-shaped end member 42, a hanging member 43, an upper end main bar 45, a lower end main bar 46, and a lattice member 47. The deck plate 41 is made of a galvanized steel plate, and forms the lower surface of each concrete block (31a to 36b).

[0022] A plurality of end members 42 are arranged spaced apart near the end of the deck plate 41. Each end member 42 has an L-shaped horizontal portion welded to the deck plate 41, and an L-shaped vertical portion fixed to the ends of the upper end main reinforcement 45, the lower end main reinforcement 46, and the lattice material 47.

[0023] The hanging member 43 has a mountain shape and is arranged in a direction perpendicular to the main reinforcements (45, 46). The upper end of the hanging member 43 is fixed so as to be wound around the upper surface of the upper end main reinforcement 45, and the flat portion of the lower end is fixed to the deck plate 41.

[0024] As shown in Figures 3 and 4, the upper end main reinforcement 45 and the lower end main reinforcement 46 are arranged vertically spaced apart. The lattice material 47 is arranged between these main reinforcements (45, 46). Specifically, the lattice material 47 has a substantially wave-shaped shape and abuts against the upper end main reinforcement 45 and the lower end main reinforcement 46. The above-mentioned hanging material 43 is also located at the abutment point between the lattice material 47 and the upper end main reinforcement 45.

[0025] For the Fellow Deck 40 configured as described above, for example, the "Fellow Eco (registered trademark) deck" by Tokyo Fujisho Co., Ltd. can be used. Furthermore, a plurality of distribution reinforcements 48 are fixed onto the upper end main reinforcement 45 in a state where they are spaced apart so as to extend in a direction perpendicular to the main reinforcements (45, 46).

[0026] Then, with the deck plate 41 forming the underside of each concrete block (31a to 36b), the end members 42, hanging members 43, upper end main bars 45, lower end main bars 46, lattice materials 47 of the fell deck 40, and distribution bars 48 are embedded in the concrete C1.

[0027] (Floor slab formation method) Next, a method for forming the floor slab 11 having the above-mentioned configuration will be described with reference to Figs.

[0028] First, a floor slab with a through hole formed therein is constructed (step S10). Specifically, in a state in which a through hole 11h is formed in the floor slab 11, a peripheral portion 11s of the openable portion 20 is constructed. In this case, the periphery of the openable portion 20 is supported by the girder 12.

[0029] Next, a small beam or the like is placed on the opening surface of the through hole (step S11). Specifically, the small beam 21 to which the PC board receiving member 25 is fixed is fixed to the main beam 12. Furthermore, the small beam 22 is fixed to the main beam 12 and the small beam 21. In this case, as shown in FIG. 5, the small beams 21 and 22 are joined together using a mounting plate 23.

[0030] Next, the fellow deck is placed (step S12). Specifically, the end of the deck plate 41 of the fellow deck 40 is placed on the mounting plate 13 of the main girder 12, the upper flange 22f of the secondary girder 22, and the PC board receiving member 25. At this time, the rubber sheets 13s, 22s, the insert 14 with the bolt 15 inserted, etc. may also be placed.

[0031] Next, a concrete formwork is placed (step S13). Specifically, the formwork F1 is fixed onto the mounting plate 13 along the inner circumferential surface of the through hole 11h. 7, a formwork F2 is arranged in a lattice shape in the space of the through hole 11h. This formwork F2 is arranged above the joists 21, 22 and the PC board receiving member 25 as supporting members. These formwork F2 partition areas 51a, 51b, 52a, 52b, 53a, 53b, 54a, 54b, 55a, 55b, etc. in which the concrete blocks (31a to 35b) are to be formed. Here, the formwork F1, F2 is made of, for example, a plurality of pieces of wood, etc., and is arranged so as to be at the same height as the upper surface of the peripheral portion 11s.

[0032] Furthermore, fixing members 57 made of long rectangular timber or the like are placed at the longitudinal center of each region (51a to 55b). These fixing members 57 are fixed to the upper surfaces of the multiple formwork F2 extending in the vertical direction in Fig. 7, and are also fixed to the left-right peripheral portion 11s of the openable portion 20. Furthermore, fixing members 58 are attached to the upper surfaces of the formwork F2 between the fixing members 57 so as to diagonally span the corner formed by this formwork F2 and the formwork F2 perpendicular to it.

[0033] Then, concrete is poured (step S14). First, concrete is poured into a plurality of non-adjacent areas (every other area) (first pouring stage). Specifically, concrete is poured into areas 51a, 52b, 53a, 54b, 55a, etc., which are the first areas. In this case, the concrete is poured up to approximately the same height as the lower surfaces of the fixing members 57 and 58. Then, hanging bolts B1 are placed at the upper ends of the four corners of the areas into which the concrete is poured. After that, the concrete is left to harden.

[0034] Then, after the concrete in the areas 51a, 52b, 53a, 54b, 55a, . . . where it was poured first has hardened, the fixing members 57, 58 are removed. As a result, concrete blocks 31a, 32b, 33a, 34b, 35a . . . are formed in the regions 51a, 52b, 53a, 54b, 55a .

[0035] Next, concrete is poured into the uncast area adjacent to the area where the concrete blocks have been formed (second casting stage). Specifically, concrete is poured into areas 51b, 52a, 53b, 54a, 55b... as the second area adjacent to the already formed concrete blocks 31a, 32b, 33a, 34b, 35a... In this case, the concrete is poured so that it is formed at the same height as the top surface of the already formed concrete blocks. In this case as well, the hanging bolts B1 are placed at the four corners of the area where the concrete is poured. Then wait for it to harden. In this manner, all of the concrete blocks (31a to 36b) are formed.

[0036] Next, the concrete forms are removed (step S15). Specifically, the form F1 between the concrete blocks (31a to 36b) and the surrounding portion 11s, and the form F2 between the concrete blocks (31a to 36b) are removed.

[0037] Then, sealing members are formed (step S16). Specifically, sealing material is injected into gaps that are generated by removing the forms F1 and F2, thereby forming sealing members 38 and 39. As a result of the above, the floor slab 11 having the openable portion 20 in a state in which the through hole 11h is blocked with the plurality of concrete blocks (31a to 36b) is completed.

[0038] (Method of forming openings) Next, a method of forming an opening in the openable portion 20 in order to construct the internal staircase 18 connected to the floor slab 17 of the floor immediately below shown in FIG. 1 will be described.

[0039] In this case, first, the sealing members are removed. Specifically, the sealing members 38 and 39 are removed. As a result, gaps are generated between the peripheral portion 11s of the openable portion 20 of the floor slab 11 and the concrete blocks (31a to 36b), and between the concrete blocks (31a to 36b). Furthermore, the bolts 15, the inserts 14, the rubber sheets 13s and 22s, etc. are removed.

[0040] Next, the concrete blocks (31a to 36b) are removed one by one from the openable portion 20. For example, one concrete block (31a, etc.) is lifted by the hanging bolts B1 at its four corners with a winch or the like, and removed from the openable portion 20. The removed concrete block (31a, etc.) is transported to the ground by an elevator or the like.

[0041] Then, after all of the concrete blocks (31a to 36b) have been removed, the small beams 21, 22 and the mounting plate 23 arranged in the openable portion 20 are removed. In this case, the PC board receiving member 25 attached to the small beam 22 is also removed from the openable portion 20.

[0042] As a result of the above, the through hole 11h appears in the openable portion 20, and an opening is formed in the floor slab 11. Then, an internal staircase 18 is constructed through this opening to connect the floor slab 11 and the floor slab 17. Thereafter, in order to close the opening (through hole 11h) again, the above-mentioned steps S11 to S16 are carried out.

[0043] (Action of this embodiment) Since the concrete blocks (31a-36a) are formed by pouring into place to match the height of the upper surface of the peripheral portion 11s of the openable portion 20, the upper surfaces of the concrete blocks (31a-36a) and the upper surface of the peripheral portion 11s are approximately the same height.

[0044] According to this embodiment, the following effects can be obtained. (1) In this embodiment, the through hole 11h of the openable portion 20 is blocked with a concrete block (31a to 36b) formed by casting in place. This makes it possible to efficiently and quickly form the concrete block (31a to 36b) having an upper surface at the same height as the upper surface of the surrounding portion 11s. Therefore, it is possible to suppress the occurrence of a step and to construct the openable portion 20 in which the through hole 11h is efficiently blocked.

[0045] (2) In this embodiment, a formwork F2 is placed above the joists 21, 22 and the PC board receiving member 25 that are arranged in a lattice pattern on the opening surface of the through hole 11h. This makes it possible to form concrete blocks (31a to 36b) of a transportable size that corresponds to the area partitioned to correspond to the joists 21, 22 and the PC board receiving member 25.

[0046] (3) In this embodiment, a form F1 is placed on the inner periphery of the through hole 11h, and a form F2 is placed to separate the regions (51a to 55b, etc.). After the concrete blocks (31a to 36b) are formed, the forms F1, F2 are removed, and sealing members 38, 39 are formed in the places where the forms F1, F2 were previously located. When an opening is to be formed, the sealing members 38, 39 are removed. As a result, the portions of the sealing members 38, 39 become gaps, so that the concrete blocks (31a to 36b) can be efficiently removed one by one.

[0047] (4) In this embodiment, after the first pouring stage is performed to form concrete blocks in areas that are not adjacent to every other concrete block, the second pouring stage is performed to form concrete blocks in areas adjacent to the formed concrete blocks. As a result, the areas adjacent to the pre-hardened concrete blocks are not flowing concrete parts, so that work such as leveling the top surface of the poured concrete can be performed efficiently.

[0048] (5) In this embodiment, fixing members 57, 58 that fix the position of the formwork F2 before pouring concrete are provided in the region (51a to 55b) of the openable portion 20. This makes it possible to prevent the concrete block formed first in the first pouring stage from being deformed by the pressure of the concrete.

[0049] (6) In this embodiment, the fixing member 57 is fixed to the upper surface of the surrounding portion 11s of the through hole 11h, and the fixing member 58 is fixed to the upper surface of the formwork F2. Therefore, concrete can be poured while referring to the height of the lower surfaces of the fixing members 57 and 58 so that there is no difference in height between the upper surface of the surrounding portion 11s and the lower surfaces of the fixing members 57 and 58.

[0050] (7) In this embodiment, each concrete block (31a to 36b) is formed by embedding a fell deck 40 formed by integrating upper end main reinforcement 45, lower end main reinforcement 46, etc., with a deck plate 41 in concrete C1. This makes it possible to efficiently form the concrete blocks (31a to 36b).

[0051] (8) In this embodiment, the reinforcement bars 48 are embedded in each of the concrete blocks (31a to 36b). This makes it possible to increase the strength against tensile forces in a direction perpendicular to the main reinforcements (45, 46) of the fellow deck 40.

[0052] This embodiment can be modified as follows: This embodiment and the following modifications can be combined with each other to the extent that there is no technical contradiction. In the above embodiment, the concrete block is formed using the fellow deck 40. Instead of using the fellow deck, a concrete block may be formed by laying a known deck plate and then arranging main reinforcement.

[0053] In the above embodiment, in each concrete block (31a to 36b), the distribution bars 48 are embedded in the concrete C1 together with the fello deck 40. Alternatively, the concrete block may be configured without distribution bars. Also, the concrete block formed in the first pouring stage may be configured with distribution bars, but the concrete block formed in the second pouring stage may be configured without distribution bars.

[0054] In the above embodiment, the openable portion 20 uses 2 rows x 6 concrete blocks (31a to 36b) to close the through hole 11h. The number and arrangement of the concrete blocks are not limited to this. Depending on the size of the through hole, multiple concrete blocks may be arranged in one row. The shape and size of the concrete blocks are also not limited to this. The concrete blocks only need to have a weight and size that allows them to be transported when forming the opening. In addition, when the horizontal cross section of the through hole is round or the like, the concrete blocks may be fan-shaped instead of rectangular.

[0055] In the above embodiment, the concrete is poured in two stages, the first pouring stage and the second pouring stage. The method of pouring the concrete is not limited to this, and the concrete may be poured in a plurality of stages or all the concrete may be poured at once.

[0056] Next, the technical ideas that can be understood from the above embodiment and other examples will be described below. (a) After the poured concrete has hardened, the formwork is removed; 4. The method for forming a floor slab according to claim 2 or 3, further comprising the step of placing a sealing member in the area from which the formwork has been removed.

[0057] (b) After installing a fello deck, which is an integrated deck of floor plates and reinforcing bars, so as to span the support members, 4. The method for forming a floor slab according to any one of claims 1 to 3 or (a), characterized in that the portion above the floor plate is poured with the concrete. [Explanation of symbols]

[0058] B1...hanging bolt, C1...concrete, F1, F2...formwork, 11, 17...floor slab, 11h...through hole, 11s...surrounding part, 12...main beam, 12f, 22f...upper flange, 13, 23...mounting plate, 13s, 22s...rubber sheet, 14...insert, 15...bolt, 18...inner staircase, 20...openable part, 21, 22...minor beam, 21w, 22w...web, 25...PC board support member, 31a, 31b, 32a, 3 2b, 33a, 33b, 34a, 34b, 35a, 35b, 36a, 36b...concrete blocks, 38, 39...sealing members, 40...fellow deck, 41...deck plate, 42...end members, 43...hanging members, 45...upper end main bars, 46...lower end main bars, 47...lattice members, 48...distribution bars, 51a, 51b, 52a, 52b, 53a, 53b, 54a, 54b, 55a, 55b...areas, 57, 58...fixing members.

Claims

1. 1. A method for forming a floor slab for a building, comprising: A through hole is provided in the floor slab, dividing an opening surface of the through hole into a plurality of regions each having a predetermined size or less by a support member; A method for forming a floor slab, characterized in that an openable portion that blocks the through hole is formed in the floor slab by pouring concrete into each of the areas partitioned in the through hole to correspond to the support member.

2. The concrete formwork is placed on the inner peripheral edge of the through hole; A form for dividing the area is disposed above the support member; 2. The method of claim 1, further comprising pouring the concrete into the area enclosed by the formwork.

3. The plurality of regions are arranged in a plurality of rows, A first pouring step of forming a plurality of first regions that are not adjacent to each other in the plurality of regions by first pouring the concrete; The method for forming a floor slab according to claim 1 or 2, further comprising a second casting step of forming a second area adjacent to the first area by casting after the first casting step.

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