Floor structure and construction method of floor structure

Abstract

This invention provides a floor structure and a construction method for the floor structure that can shorten the construction process and ensure aesthetic appeal. [Solution] A floor structure 100 comprising an RC slab 10 used as flooring material for the upper floor, a panel-shaped wooden member 12 provided along the lower surface of the RC slab 10, the upper surface of which is used as formwork material for the RC slab 10 and the lower surface of which is used as ceiling finishing material for the lower floor, and a beam member 14 provided on the lower side of the RC slab 10 at the side end 22 of the wooden member 12, wherein the beam member 14 has a support member 16 provided on its side, and the side end 22 of the wooden member 12 is fixed on the support member 16.

Description

Technical Field

[0001] The present invention relates to a floor structure and a construction method of the floor structure.

Background Art

[0002] Conventionally, as one of the methods for promoting the use of wood in mid-rise and high-rise buildings, Cross Laminated Timber (CLT), which is an orthogonal laminated board, has been known to be used as both a formwork material when placing a Reinforced Concrete (RC) slab and a ceiling finishing material (for example, see Patent Document 1).

[0003] FIG. 4 shows an example thereof. As shown in this figure, CLT 2 is disposed below an RC slab 1 forming a floor. Side portions of the CLT 2 are connected to wooden beam members 3. The RC slab 1 functions as a main structural part (floor that bears loads) alone, and the CLT 2 has a role of imparting vibration damping performance and sound insulation performance to the floor, rather than serving as a main structural part. Since the CLT 2 is not a main structural part, there is no need to provide a fireproof coating material for the CLT 2 even in the case of a fireproof building, and the wood can be left in an exposed state as a ceiling finishing material. In a general construction method, the slab formwork material is discarded after use, but in the construction method of this figure, it remains in the building as a ceiling finishing material and is not discarded, thus contributing to the reduction of the amount of waste during construction.

[0004] On the other hand, as prior arts related to a composite floor structure of CLT and reinforced concrete, for example, those described in Patent Documents 2, 3, and Non-Patent Document 1 are known. Since these technologies integrate the CLT and the RC slab and make both function as main structural parts, it is necessary to provide a fireproof coating material for the CLT.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

[0006] [Non-Patent Document 1] "Experimental Study on the Bending Performance of Composite Floor Slabs Made by Laminating Reinforced Concrete and CLT and Joining them with Shear Keys," Fumiaki Ohki et al., Journal of Concrete Engineering, Vol. 32, pp. 13-23, 2021. [Overview of the project] [Problems that the invention aims to solve]

[0007] By the way, in the conventional structure shown in Figure 4 above, the following problems arise because the underside of the CLT2 needs to be supported from below by temporary supports such as steel columns when constructing the RC slab 1. First, since the temporary supports for the upper floor cannot be erected until the RC slab pouring for the lower floor is complete, the construction becomes a cumulative process, which may increase the number of construction days. Also, the receiving plates installed at the upper end of the temporary supports may cause indentation and staining on the underside of the CLT2, which also serves as the ceiling finishing material, potentially impairing the aesthetic appearance.

[0008] The present invention has been made in view of the above, and aims to provide a floor structure and a method for constructing a floor structure that can shorten the construction process and ensure aesthetic appeal. [Means for solving the problem]

[0009] To solve the above-mentioned problems and achieve the objective, the floor structure according to the present invention comprises an RC slab used as a flooring material for the upper floor, a panel-shaped wooden member provided along the lower surface of the RC slab, the upper surface of which is used as a formwork material for the RC slab and the lower surface of which is used as a ceiling finishing material for the lower floor, and a beam member provided on the lower side of the RC slab at the side end of the wooden member, wherein the beam member has a support member provided on its side, and the side end of the wooden member is fixed on the support member.

[0010] Furthermore, another floor structure according to the present invention is characterized in that, in the above-described invention, the support member is an angle material with an L-shaped cross-section, one piece of the angle material is fixed to the side of the beam material, the other piece of the angle material protrudes toward the wooden material, a notched step is formed in the lower part of the side end of the wooden material, and the lower surface of the step is placed on the upper surface of the other piece of the angle material.

[0011] Furthermore, another floor structure according to the present invention is characterized in that, in the above-described invention, the beam member is a wooden beam, one piece of the angle material is fixed to the side of the beam member with a lag screw bolt, and the rotation of the angle material is restrained by the tensile force from the lag screw bolt and the compressive force on the beam member.

[0012] Furthermore, another floor structure according to the present invention is characterized in that, in the above-described invention, the beam member is a steel beam made of H-shaped steel, and one piece of the angle material is welded to the beam member via a rib plate fixed to the beam member.

[0013] Furthermore, the method for constructing the floor structure according to the present invention is a method for constructing the floor structure described above, characterized by comprising the steps of: attaching the support member to the beam member in advance, then setting and fixing the wooden member on the support member; and then using the wooden member as formwork material and constructing the RC slab on the wooden member. [Effects of the Invention]

[0014] The floor structure according to the present invention comprises an RC slab used as a flooring material for the upper floor, a panel-shaped wooden member provided along the lower surface of the RC slab, with its upper surface used as formwork material for the RC slab and its lower surface used as a ceiling finishing material for the lower floor, and a beam member provided on the lower side of the RC slab at the side end of the wooden member, wherein the beam member has a support member provided on its side, and the side end of the wooden member is fixed on the support member. Therefore, when using the wooden member as formwork material when pouring the RC slab, the wooden member is placed on the support member fixed to the beam member, eliminating the need for temporary support to support the wooden member. Furthermore, there is no risk of the wooden member sinking into the lower surface or becoming soiled, thus avoiding any loss of aesthetic appeal. As a result, the construction process can be shortened while maintaining aesthetic appeal.

[0015] Furthermore, according to another floor structure of the present invention, the support member is an angle material with an L-shaped cross-section, one piece of the angle material is fixed to the side of the beam member, the other piece of the angle material protrudes toward the wooden member, a notched step is formed in the lower part of the side end of the wooden member, and the lower surface of the step is placed on the upper surface of the other piece of the angle material, thus providing the effect that the wooden member can be easily installed on the angle material.

[0016] Furthermore, according to another floor structure of the present invention, the beam member is a wooden beam, and one piece of the angle material is fixed to the side of the beam member with a lag screw bolt. The rotation of the angle material is restrained by the tensile force from the lag screw bolt and the compressive force on the beam member, thereby providing the effect of stably fixing the wooden member via the angle material.

[0017] Further, according to another floor structure of the present invention, the beam member is a steel frame beam made of H-shaped steel, and one piece of the angle member is welded to the beam member via a rib plate fixed to the beam member, so that the wooden member can be stably fixed via the angle member.

[0018] Further, according to the construction method of the floor structure of the present invention, it is a method of constructing the above-described floor structure, including a step of attaching the support member to the beam member in advance and then installing and fixing the wooden member on the support member, and then a step of using the wooden member as a formwork material and constructing the RC slab on the wooden member, so that it is possible to shorten the construction process and ensure the designability.

Brief Description of the Drawings

[0019] [Figure 1] FIG. 1 is a side sectional view showing Embodiment 1 of the floor structure and the construction method of the floor structure according to the present invention. [Figure 2] FIG. 2 is an explanatory view of the rotational deformation of the angle member with respect to the construction load. [Figure 3] FIG. 3 is a side sectional view showing Embodiment 2 of the floor structure and the construction method of the floor structure according to the present invention. [Figure 4] FIG. 4 is a schematic perspective sectional view showing an example of a conventional floor structure.

Embodiments for Carrying Out the Invention

[0020] Hereinafter, embodiments of the floor structure and the construction method of the floor structure according to the present invention will be described in detail based on the drawings. Note that the present invention is not limited by this embodiment.

[0021] (Embodiment 1) First, Embodiment 1 of the present invention will be described. As shown in Figure 1, the floor structure 100 according to Embodiment 1 of the present invention is applied to a floor structure having wooden beams. This floor structure 100 comprises an RC slab 10, a CLT panel 12 provided along the lower surface of the RC slab 10, wooden beams 14, and angle members 16.

[0022] RC slab 10 is made of reinforced concrete and is used as flooring material for the upper floors. RC slab 10 is a major structural component that supports vertical loads and partitions between floors.

[0023] The CLT panel 12 is a CLT panel (a panel-shaped timber member) made by alternately laminating and bonding sawn timbers so that their fiber directions are perpendicular to each other. The CLT panel 12 is used as a vibration-damping and sound-insulating material, and is not a main structural component; it does not support the load of the structure and does not form inter-story partitions. The CLT panel 12 is installed between timber beams 14 that are spaced apart horizontally. In the example shown in the figure, only one timber beam 14 is shown, and the timber beams 14 spaced horizontally from this timber beam 14 are not shown. The top surface of the CLT panel 12 and the top surface of the timber beams 14 are flush.

[0024] Multiple shear keys 18 are provided at intervals on the upper surface of the CLT panel 12. The shear keys 18 are made up of, for example, lag screws or structural screws, with their lower ends inserted into the CLT panel 12 from above, and their upper ends protruding above the upper surface of the CLT panel 12 and anchored to the concrete of the RC slab 10. The upper surface of the CLT panel 12 is used as formwork material for the concrete of the RC slab 10.

[0025] A finishing material 20 is provided on the underside of the CLT panel 12. The finishing material 20 extends laterally beyond the side end 22 of the CLT panel 12. A square timber 24 is provided on the upper surface of the end of the finishing material 12, which is in close contact with the surface of the wooden beam 14. Since the underside of the CLT panel 12 can also be used as the ceiling finishing material for the floor below, this finishing material 20 can be omitted. If the finishing material 20 is omitted, the underside of the CLT panel 12 will be left exposed downwards and will serve as the ceiling finishing material for the floor below.

[0026] A gap 26 is provided between the side end 22 of the CLT panel 12 and the wooden beam 14. A rectangular cutout 28 is formed at the lower corner of the side end 22 of the CLT panel 12 when viewed from the front in the figure. The lower surface 30 of the step 28 is horizontal and rests on the angle member 16. This step 28 allows the CLT panel 12 to be easily installed on the angle member 16.

[0027] The CLT panel 12 is fixed to the timber beam 14 via connecting hardware. This fixing method involves, for example, positioning a plate (connecting hardware) so as to straddle the upper surface of the timber beam 14 and the upper surface of the CLT panel 12, and driving screws through multiple through holes in the plate into the upper surface of the timber beam 14 and the upper surface of the CLT panel 12, thereby fixing the CLT panel 12 to the timber beam 14 via the plate and screws. When arranging multiple CLT panels 12 in a row along the longitudinal direction of the timber beam 14, adjacent CLT panels 12 may be fixed to each other using the plate and screws described above. In this case, only the reference CLT panel 12 may be fixed to the timber beam 14.

[0028] In this embodiment 1, the CLT panel 12 is assumed to be a 5-layer, 5-ply panel with a thickness of approximately 150 mm, but the present invention is not limited to this. Furthermore, the height of the notch in the stepped portion 28 of the side end 22 is assumed to be approximately 57 mm. In this case, a thickness of approximately 93 mm is secured above the stepped portion 28 of the side end 22 of the CLT panel 12. This makes it possible to achieve a fitting in which the top surface of the wooden beam 14 and the top surface of the CLT panel 12 coincide.

[0029] The timber beam 14 is a beam member provided on the side of the side end 22 of the CLT panel 12, below the RC slab 10. The timber beam 14 has a rectangular cross-section and is composed of a timber core material 32 extending horizontally (depth direction in Figure 1), fire-resistant covering material 34 provided on the sides and bottom of the core material 32, and a finishing material 36. The core material 32 can be made using laminated timber such as larch. The fire-resistant covering material 34 is composed of two reinforced gypsum boards 34A provided on the outside of the core material 32 and a fire-resistant sheet 34B provided on the outside of those. The fire-resistant sheet 34B is a thermally expanding fire-resistant sheet that expands when heated, and the combustion residue forms a fire-resistant insulation layer, exhibiting fire-resistant insulation performance. The finishing material 36 is made of a wooden board provided on the outside of the fire-resistant sheet 34B. Multiple shear keys 18 are provided at intervals on the upper surface of the core material 32. In this embodiment 1, the core material 32 is assumed to have a cross-sectional width of 400 mm and a height of 900 mm, the reinforced gypsum board 34A has a thickness of 25 mm, the fire-resistant sheet 34B has a thickness of 2 mm, and the wooden board of the finishing material 36 has a thickness of 15 mm. However, the present invention is not limited to this.

[0030] The angle member 16 is a support member made of L-shaped steel and is provided on the outer surface (side) of the finishing material 36 of the timber beam 14. One side 16A of the angle member 16 extends vertically upward, and its outer surface is fixed to the finishing material 36. The other side 16B of the angle member 16 protrudes horizontally toward the side end 22 of the CLT panel 12. The lower surface 30 of the stepped portion 28 of the side end 22 of the CLT panel 12 abuts against the upper surface of the other side 16B of the angle member 16. A through hole 38 is provided in one side 16A of the angle member 16. One side 16A of the angle member 16 is fixed to the side of the timber beam 12 by a lag screw bolt 40 inserted through the through hole 38. In this embodiment 1, an L-shaped steel of 100 × 75 × 7 mm is assumed as the angle member 16, but the present invention is not limited to this. If the dimensions of angle material 16 are 100 x 75 x 7 mm, then the vertical length of one side 16A of angle material 16 is 100 mm, the horizontal length of the other side 16B is 75 mm, and the thickness of the material is 7 mm.

[0031] The lag screw bolt 40 comprises a substantially cylindrical bolt body 42 with threads formed thereon, and a base 44 that is continuous with the rear end of the bolt body 42 and does not have threads. The bolt body 42 is screwed into a pilot hole provided in the core material 32, and the base 44 is positioned to penetrate the fire-resistant coating material 34 and the finishing material 36. The position of the rear end of the base 44 coincides with the surface of the finishing material 36. A screw hole 46 is provided inside the base 44. One piece 16A of the angle material 16 is fixed to the wooden beam 14 with a bolt 50 with a flange 48 that is screwed from the through hole 38 into the screw hole 46.

[0032] As shown in Figure 2, the angle member 16 attempts to rotate as indicated by the dashed line, but the rotation of the angle member 16 is restrained by the tensile force from the lag screw bolt 40 and the compressive force on the timber beam 14. In this way, the CLT panel 12 can be stably fixed via the angle member 16. In this embodiment 1, the lag screw bolt 40 is assumed to have a bolt body 42 with a diameter of 30.5 mm, a total length including the bolt body 42 and base 44 of 215 mm, and an arrangement interval of 400 mm, but the present invention is not limited to this.

[0033] Next, an example of a construction method for the floor structure according to this embodiment 1 will be described. First, as a preliminary step, the angle members 16 are attached to the wooden beam 14 in advance using lag screw bolts 40, and then the wooden beam 14 is installed at the planned construction location on site. Alternatively, the angle members 16 may be attached to the wooden beam 14 after it has been installed at the planned construction location.

[0034] In the next step, the side end 22 of the CLT panel 12 is placed on top of the angle member 16 of the timber beam 14. This allows the CLT panel 12 to be easily installed on the angle member 16. After that, the CLT panel 12 is positioned and the top surface of the CLT panel 12 and the top surface of the timber beam 14 are fixed together using the aforementioned connecting hardware. This fixes the side end 22 of the CLT panel 12 to the angle member 16. It is desirable to fix the shear key 18 and finishing material 20 to the CLT panel 12 in advance before placing the CLT panel 12 on the angle member 16. After that, reinforcement work is carried out at the planned concrete pouring location for the RC slab 10 above the CLT panel 12, and then the CLT panel 12 is used as formwork material to pour concrete for the RC slab 10 on top of the CLT panel 12 and the timber beam 14. In this way, the floor structure 100 is constructed. The CLT panel 12 remains in this state even after the concrete is poured.

[0035] According to the construction method of this embodiment 1, when using the CLT panel 12 as formwork material when pouring the RC slab 10, the CLT panel 12 is placed on an angle material 16 fixed to the wooden beam 14, thereby eliminating the need for temporary supports that were conventionally required to support the CLT panel 12. As a result, the construction process can be shortened. For example, the steel frame cycle can be a typical 2-layer, 1-section cycle. Also, since temporary supports are not required, there is no risk of the CLT panel 12 sinking into or soiling the finishing material 20 on the underside, thus avoiding any loss of aesthetic appeal as a ceiling. For this reason, this embodiment 1 makes it possible to shorten the construction process and ensure aesthetic appeal.

[0036] Furthermore, the inventors have manufactured a full-scale mock-up of the floor structure 100 described above and have confirmed the ease of construction and the structural performance during construction in the process of placing the CLT panels 12 on the angle members 16. As a result, it has been confirmed that the effects of this embodiment 1 can be obtained appropriately.

[0037] (Embodiment 2) Next, Embodiment 2 of the present invention will be described. As shown in Figure 3, the floor structure 200 according to Embodiment 2 of the present invention is applied to a floor structure having steel beams. This floor structure 200 comprises an RC slab 10, a CLT panel 12 provided along the lower surface of the RC slab 10, steel beams, and angle members. The RC slab, CLT panel, and angle members are the same as those described in Embodiment 1 above, and a detailed explanation of them is omitted.

[0038] The steel beam 52 is a beam member made of H-shaped steel having an upper flange 54, a lower flange 56, and a web 58. The upper surface of the upper flange 54 and the upper surface of the CLT panel 12 are flush. A vertical plate-shaped rib plate 60 is provided on the lower surface of the upper flange 54. The rib plate 60 is fixed at a right angle to the upper flange 54 and the upper portion of the web 58, respectively, by welding. The side end of the rib plate 60 and the side end of the upper flange 54 are flush. The outer surface of one piece 16A of the angle material 16 is welded to the side end of the rib plate 60 and the side end of the upper flange 54. In this embodiment 2, the H-shaped steel of the steel beam 52 is assumed to be H-700×300×14×25, and the rib plate 60 is assumed to be 6 mm thick and spaced 1000 mm apart in the longitudinal direction, but the present invention is not limited to this.

[0039] Next, an example of a construction method for the floor structure according to this second embodiment will be described. First, as a preliminary step, angle members 16 are attached to the steel beam 52 by welding in advance, and then the steel beam 52 is installed at the planned construction location on site. Alternatively, the angle members 16 may be attached to the steel beam 52 after it has been installed at the planned construction location.

[0040] In the next step, the side end 22 of the CLT panel 12 is placed on top of the angle member 16 of the steel beam 52. This allows the CLT panel 12 to be easily installed on the angle member 16. After that, the CLT panel 12 is positioned and the top surface of the CLT panel 12 is fixed to the upper flange 54 of the steel beam 52 via connecting hardware. This fixes the side end 22 of the CLT panel 12 to the angle member 16. It is desirable to fix the shear key 18 and finishing material 20 to the CLT panel 12 in advance before placing the CLT panel 12 on the angle member 16. After that, reinforcement work is carried out at the planned concrete pouring location for the RC slab 10 above the CLT panel 12, and then the CLT panel 12 is used as formwork material to pour concrete for the RC slab 10 on top of the CLT panel 12 and the steel beam 52. In this way, the floor structure 200 is constructed. The CLT panel 12 remains in this state even after the concrete is poured.

[0041] According to the construction method of this second embodiment, when using the CLT panel 12 as formwork material when pouring the RC slab 10, the CLT panel 12 is placed on an angle material 16 fixed to the steel beam 52, thereby eliminating the need for temporary supports that were conventionally required to support the CLT panel 12. As a result, the construction process can be shortened. For example, the steel frame cycle can be a typical two-layer, one-section cycle. Also, since temporary supports are not required, there is no risk of the CLT panel 12 sinking into or soiling the finishing material 20 on the underside, thus avoiding any impairment of the aesthetic appearance of the ceiling. For this reason, this second embodiment makes it possible to shorten the construction process and ensure aesthetic appearance.

[0042] As described above, the floor structure according to the present invention comprises an RC slab used as a flooring material for the upper floor, a panel-shaped wooden member provided along the lower surface of the RC slab, with its upper surface used as formwork material for the RC slab and its lower surface used as a ceiling finishing material for the lower floor, and a beam member provided on the lower side of the RC slab at the side end of the wooden member, wherein the beam member has a support member provided on its side, and the side end of the wooden member is fixed on the support member. Therefore, when using the wooden member as formwork material when pouring the RC slab, the wooden member is placed on the support member fixed to the beam member, eliminating the need for temporary support to support the wooden member. Furthermore, there is no risk of the wooden member sinking into the lower surface or becoming soiled, thus avoiding any loss of aesthetic appeal. For this reason, the construction process can be shortened and aesthetic appeal can be ensured.

[0043] Furthermore, according to another floor structure of the present invention, the support member is an angle material with an L-shaped cross-section, one piece of the angle material is fixed to the side of the beam material, the other piece of the angle material protrudes toward the wooden material, a notched step is formed in the lower part of the side end of the wooden material, and the lower surface of the step is placed on the upper surface of the other piece of the angle material, so that the wooden material can be easily installed on the angle material.

[0044] Furthermore, according to another floor structure of the present invention, the beam member is a wooden beam, and one piece of the angle material is fixed to the side of the beam member with a lag screw bolt, and the rotation of the angle material is restrained by the tensile force from the lag screw bolt and the compressive force on the beam member, so that the wooden member can be stably fixed via the angle material.

[0045] Furthermore, according to another floor structure of the present invention, the beam member is a steel beam made of H-shaped steel, and one piece of the angle material is welded to the beam member via a rib plate fixed to the beam member, so that the wooden member can be stably fixed via the angle material.

[0046] Furthermore, according to the construction method for the floor structure of the present invention, the method for constructing the floor structure described above includes the steps of first attaching the support member to the beam member, then setting and fixing the wooden member on the support member, and then using the wooden member as formwork material to construct the RC slab on the wooden member, thereby shortening the construction process and ensuring aesthetic appeal. [Industrial applicability]

[0047] As described above, the floor structure and construction method for the floor structure according to the present invention are useful for floor structures of medium- and high-rise buildings using wood, and are particularly suitable for shortening the construction process and ensuring aesthetic appeal. [Explanation of Symbols]

[0048] 10 RC slab 12 CLT panels (wood-based materials) 14 Wooden beam (beam member) 16. Angle material (support member) 16A piece 16B Other pieces 18 Sea Key 20,36 Finishing materials 22 Side edge 24 square timber 26 gaps 28 Stepped section 30 Bottom side 32 Core material 34 Fireproof cladding 40 lag screw bolts 52 Steel beam (beam member) 60 Rib Plate 100,200 floor structure

Claims

1. A floor structure comprising an RC slab used as flooring material for the upper floor, a panel-shaped wooden member provided along the lower surface of the RC slab, with its upper surface used as formwork material for the RC slab and its lower surface used as ceiling finishing material for the lower floor, and a beam member provided on the lower side of the RC slab at the side end of the wooden member, A floor structure characterized by having a support member provided on the side of the beam member, wherein the side end of the wooden member is fixed on the support member.

2. The floor structure according to claim 1, characterized in that the support member is an angle material having an L-shaped cross-section, one piece of the angle material is fixed to the side of the beam member, the other piece of the angle material protrudes toward the wooden member, a notched step is formed in the lower part of the side end of the wooden member, and the lower surface of the step is placed on the upper surface of the other piece of the angle material.

3. The floor structure according to claim 2, characterized in that the beam member is a wooden beam, one piece of the angle material is fixed to the side of the beam member with a lag screw bolt, and the rotation of the angle material is restrained by the tensile force from the lag screw bolt and the compressive force on the beam member.

4. The floor structure according to claim 2, wherein the beam member is a steel beam made of H-shaped steel, and one piece of the angle material is welded to the beam member via a rib plate fixed to the beam member.

5. A method for constructing a floor structure according to any one of claims 1 to 4, A method for constructing a floor structure, characterized by comprising the steps of: first attaching the support member to the beam member, then setting and fixing the wooden member on the support member; and then using the wooden member as formwork material to construct the RC slab on the wooden member.

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