JP7689051B2 - Composite floor structure and method for constructing same - Google Patents

Description

The present invention relates to a composite floor structure that includes steel beams and wooden boards, and a method for constructing this composite floor structure.

2. Description of the Related Art Conventionally, there have been composite floor structures that combine steel beams and wooden boards (see Patent Documents 1 to 3).
Patent Document 1 shows a CLT floor structure comprising steel beams, cross-laminated timber panels laid so that their edges rest on the steel beams, and concrete poured and hardened on top of the cross-laminated timber panels so as to cover the top and end faces of the cross-laminated timber panels.
Patent document 2 shows a joint structure comprising a beam with studs protruding from its top surface, a wooden floor slab supported by the beam and having through holes into which the studs are inserted, and slab concrete filled into the through holes in the wooden floor slab.
Patent document 3 shows a joint structure including a beam with a bolt protruding from its top surface, a wooden floor slab supported on the top surface of the beam, and a steel plate fixed to the bolt and the wooden floor slab to transmit horizontal forces between the bolt and the wooden floor slab.

JP 2020-105694 A JP 2019-31787 A JP 2019-39177 A

The objective of the present invention is to provide a composite floor structure that is lightweight and has a thin floor thickness, and a method for constructing the same.

The inventors came up with the present invention after noticing that a composite floor structure in which steel beams and wooden boards are joined together, by attaching wooden boards to the sides of the webs of the steel beams, is lighter than a concrete floor structure and allows the thickness of the floor structure to be thinner than a composite floor structure in which wooden boards are laid on the top surface of the steel beams.
The composite floor structure of the first invention (for example, composite floor structures 1 and 1A described later) is a composite floor structure comprising a steel beam (for example, steel beam 30 described later) and a wooden board (for example, wooden board 40 described later), the steel beam comprises a flange extending horizontally (for example, lower flange 31 and upper flange 32 described later) and a web extending vertically from the flange (for example, web 33 described later), the side end face of the wooden board (for example, side end face 40A described later) is disposed in contact with the side of the web, the web of the steel beam is provided with a protrusion protruding laterally (for example, stud 35 described later), the side end face of the wooden board is formed with a recess (for example, recess 44 described later) into which the protrusion is inserted, and the inside of the recess is filled with a filler material (for example, grout material 46 described later).

According to this invention, the floor structure is formed by attaching wooden boards to the sides of the webs of steel beams, which makes it lighter than a floor structure made of reinforced concrete, and allows the floor thickness to be thinner than a composite structure in which wooden boards are placed on top of steel beams.
In addition, the protrusions on the webs of the steel beams are inserted into the recesses of the wooden boards and the recesses are filled with a filler to seal the gaps around the protrusions and join the steel beams and wooden boards by a one-sided shear joint of the protrusions. Therefore, instead of the conventional wet method of pouring concrete into the joints between the steel beams and wooden boards at the construction site, a dry method of integrating the steel beams and wooden boards at the factory can be used, ensuring the integration of the steel beams and wooden boards in a short period of time.

The composite floor structure of the second invention is characterized in that it further comprises a reinforced concrete beam (e.g., the main beam 20 described below) that supports the wooden boards, and that the ends of the steel beams and the ends of the wooden boards that are not joined to the steel beams (e.g., the side end faces 40B described below) are joined to the beams.
According to this invention, the ends of the wooden boards that are not joined to the steel beams are joined to reinforced concrete beams, thereby realizing a composite floor structure in which steel beams, wooden boards, and reinforced concrete beams are joined.

The method for constructing a composite floor structure of the third invention is a method for constructing the composite floor structure described above, characterized in that it includes the steps of preparing a composite floor panel in which the steel beams and the wooden boards are integrated, erecting a temporary beam (e.g., temporary beam 61 described below), and placing the composite floor panel on the temporary beam (e.g., steps S1 and S2 described below), erecting beam formwork (e.g., bottom formwork 62 and side formwork 63 described below) along the side end faces of the composite floor panel (e.g., steps S3 and S4 described below), and pouring concrete inside the beam formwork to construct a beam integrated with the composite floor panel (e.g., step S5 described below).

According to this invention, a composite floor panel is placed on a temporary beam, and the temporary beam supports the composite floor panel from below. In this state, a beam formwork is erected along the side end face of the composite floor panel and concrete is poured, so that the composite floor panel and the reinforced concrete beam can be easily integrated.

The present invention provides a lightweight composite floor structure with a thin floor thickness, and a method for constructing the same.

FIG. 1 is a plan view of a composite floor structure according to a first embodiment of the present invention. FIG. 2 is a cross-sectional view of the composite floor structure of FIG. 1 along II. FIG. 2 is a cross-sectional view of the composite floor structure of FIG. 1 along line II-II. FIG. 2 is a plan view of a composite floor panel that constitutes a composite floor structure. FIG. 5 is a cross-sectional view of the composite floor panel of FIG. 4 taken along line III-III. FIG. 4 is a cross-sectional view of the composite floor panel taken along line IV-IV of FIG. 1 is a flowchart of a procedure for constructing a composite floor structure. This is an explanatory diagram of the construction procedure for a composite floor structure (Part 1, a plan view showing the arrangement of composite floor panels). This is an explanatory diagram of the construction procedure for a composite floor structure (part 2, a vertical cross-sectional view of the joint between composite floor panels). This is an explanatory diagram of the construction procedure for a composite floor structure (Part 3, a vertical cross-sectional view showing the bottom formwork for the main girder having been erected). This is an explanatory diagram of the construction procedure for a composite floor structure (Part 4, a vertical cross-sectional view showing the side formwork for the main girder installed). 4 is a longitudinal section of a composite floor structure according to a second embodiment of the present invention.

The present invention is a composite floor structure in which wooden boards are attached to the side of the web of a steel beam. In this composite floor structure, instead of laying wooden boards on top of the steel beam, wooden boards are installed on the side of the web that forms the beam depth of the steel beam and joined to the steel beam. With the composite floor structure of the present invention, the thickness of the floor structure can be kept lower than when wooden boards are laid on the top surface of the steel beam.
Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the following description of the embodiments, the same components are denoted by the same reference numerals, and the description thereof will be omitted or simplified.
Fig. 1 is a plan view of a composite floor structure 1 according to a first embodiment of the present invention. Fig. 2 is a cross-sectional view taken along line II of the composite floor structure 1 in Fig. 1. Fig. 3 is a cross-sectional view taken along line II-II of the composite floor structure 1 in Fig. 1.
The composite floor structure 1 comprises columns 10, reinforced concrete girders 20 erected between the columns 10, steel beams 30 which are steel framed minor beams erected between the girders 20, wooden boards 40 provided in the area surrounded by the girders 20 and the steel beams 30, and steel or wooden frame material 50 provided along the underside of the peripheral portion of the wooden boards 40 where they are joined to the girders 20.

The steel beam 30 comprises a lower flange 31 and an upper flange 32 extending horizontally, a web 33 extending vertically connecting the lower flange 31 and the upper flange 32, and a support flange 34 provided on the side of the web 33 and extending horizontally.
Studs 35 are provided on the web 33 of the steel beam 30 above the support flange 34 at predetermined intervals along the length of the web 33 as protrusions that protrude laterally (see FIG. 4). Air vent holes 36 are formed near the studs 35 of the web 33 for use when filling with grout material, which will be described later.
In addition, on the lower side of the support flange 34 of the web 33 of the steel beam 30, bolt insertion holes 37 for connecting adjacent steel beams 30 with bolts are formed at predetermined intervals along the longitudinal direction of the web 33. High-strength bolts 38 are inserted into the bolt insertion holes 37 of adjacent steel beams 30, and nuts 39 are tightened. Adjacent steel beams 30 are connected to each other by frictional joints using these high-strength bolts (see Figs. 3 and 8).

The wooden board 40 is rectangular in plan view and comprises CLT (Cross Laminated Timber) 41 made of seven laminated layers of planks (lamina), wooden formwork plywood 42 laminated on top of the CLT 41, and a wooden ceiling underlay 43 provided on the underside of the CLT 41.
Hereinafter, the side end surface of this wooden board 40 that is joined to the steel beam 30 will be referred to as side end surface 40A, and the side end surface that is joined to the remaining girder 20 (the side end surface of the wooden board 40 that is not joined to the steel beam 30) will be referred to as side end surface 40B.
The side end surface 40A of the wooden board 40 is disposed in contact with the side surface of the web 33 of the steel beam 30, and the end of this wooden board 40 on the side end surface 40A side of the CLT 41 is interposed between the support flange 34 and the upper flange 32 of the steel beam 30. The upper surface of the formwork plywood 42 is flush with the upper surface of the upper flange 32 of the steel beam 30. The lower surface of the ceiling base 43 and the lower surface of the frame material 50 are flush with the lower surface of the lower flange 31 of the steel beam 30.

A recess 44 is formed on the side end surface 40A of the wooden board 40, into which the stud 35 of the steel beam 30 is inserted. A grout injection hole 45 is formed on the underside of the wooden board 40, leading from the outside to the recess 44. With the stud 35 of the steel beam 30 inserted into the recess 44, grout material 46 is filled into the recess 44 through the grout injection hole 45, thereby joining and integrating the wooden board 40 with the steel beam 30.
A waterproof coating is applied to the side end surface 40B of the wooden board 40, and female threads 47 are embedded at predetermined intervals along the length of this side end surface 40B (see FIG. 4).

The girder 20 is joined to an end of the steel beam 30 and a side end surface 40B of the wooden board 40, which is an end not joined to the steel beam 30. The girder 20 is provided with a jaw portion 21 that supports from below a frame material 50 constituting the side end surface 40B of the wooden board 40. The girder 20 includes main beam reinforcement 22, stirrup reinforcement 23 provided surrounding the main beam reinforcement 22, vertical reinforcement 24 arranged in the jaw portion 21, and a concrete body 25 in which the main beam reinforcement 22, the stirrup reinforcement 23, and the vertical reinforcement 24 are embedded.
A bolt (lag screw bolt) 48 is screwed into the female threaded portion 47 of the wood board 40, and this bolt 48 is embedded in the concrete body 25 of the girder 20, thereby joining the wood board 40 to the girder 20. Note that in this embodiment, the female threaded portion 47 is provided on the side end surface 40B of the wood board 40, and the bolt 48 is screwed into this female threaded portion 47, but this is not limited thereto, and a flat steel or shaped steel protruding laterally may be provided on the side end surface 40B of the wood board 40.

In the present invention, a composite floor structure 1 is constructed by integrating steel beams 30, wooden boards 40, and frame materials 50 into a composite floor panel 60, and then laying this composite floor panel 60 and integrating it with reinforced concrete girder 20.
Figure 4 is a plan view of the composite floor panel 60. Figure 5 is a cross-sectional view of the composite floor panel 60 of Figure 4 taken along line III-III. Figure 6 is a cross-sectional view of the composite floor panel 60 of Figure 4 taken along line IV-IV.
In the composite floor panel 60, the studs 35 of the steel beams 30 are inserted into the recesses 44 of the wooden boards 40, and in this state, grout material 46 is injected as a filler through grout injection holes 45 provided on the underside of the wooden boards 40 to fill the recesses 44. The grout material 46 is injected until it overflows from the air vent holes 36. This joins the wooden boards 40 to the steel beams 30.

The procedure for constructing the composite floor structure 1 using the composite floor panel 60 will be described below with reference to the flow chart of FIG.
That is, in step S1, as shown in Figures 8 and 9, a temporary beam 61 for supporting the composite floor panel 60 is erected, and the composite floor panel 60 is placed on this temporary beam 61. As a result, the side end surface 40B of the wooden board 40 of the composite floor panel 60 is positioned on the side surface of the girder 20 (see Figure 10).
In step S2, as shown in Figures 8 and 9, adjacent composite floor panels 60 are connected to each other. Specifically, high-strength bolts 38 are inserted into the bolt insertion holes 37 of the steel beams 30 of adjacent composite floor panels 60, and nuts 39 are tightened to connect adjacent composite floor panels 60 to each other.

In step S3, as shown in Fig. 10, the bottom form 62 of the girder 20 is erected along the side end surface 40B of the composite floor panel 60, and the girder 20 and the jaw portion 21 are reinforced. Specifically, the beam main reinforcement 22 and the stirrup reinforcement 23 are assembled on the ground, and the assembled beam main reinforcement 22 and stirrup reinforcement 23 are dropped onto the bottom form 62 of the girder 20. Then, the vertical reinforcement 24 is arranged.
In step S4, the side formwork 63 of the girder 20 is erected as shown in Figure 11. After that, the bolt 48 is screwed into the female thread portion 47 of the side end surface 40B of the composite floor panel 60.
In step S5, concrete is poured inside the bottom formwork 62 and the side formwork 63 to construct the girder 20 by integrating them into the composite floor panel 60. At this time, the side end faces 40B of the wooden boards 40 that have been waterproofed function as beam formwork. After that, the side formwork 63, the bottom formwork 62, and the temporary beams 61 are dismantled.

According to this embodiment, the following effects are obtained.
(1) The composite floor structure 1 is formed by attaching wooden boards 40 to the sides of the webs 33 of the steel beams 30, which makes it lighter than a floor structure made of reinforced concrete, and allows the floor thickness to be thinner than a composite structure in which wooden boards are placed on top of steel beams.
In addition, the studs 35 provided on the webs 33 of the steel beams 30 are inserted into the recesses 44 of the wooden boards 40, and the recesses 44 are filled with grout material 46 to close the gaps around the studs 35, and the steel beams 30 and the wooden boards 40 are joined by one-sided shear joints of the studs 35. Therefore, instead of the conventional wet method of pouring concrete at the joints between the steel beams and the wooden boards at the construction site, the dry method of integrating the steel beams and the wooden boards at the factory can ensure the integration of the steel beams and the wooden boards in a short period of time. In addition, the steel beams 30 of adjacent composite floor panels 60 are joined by high-strength bolt friction joints using high-strength bolts 38 and nuts 39, so that the adjacent composite floor panels 60 can be firmly integrated.

(2) The side end surface 40B of the wooden board 40 that is not joined to the steel beam is joined to the side surface of the reinforced concrete girder 20, thereby realizing a composite floor structure 1 in which the steel beam 30, wooden board 40, and girder 20 are integrated. In addition, in the composite floor structure 1, the composite floor panel 60 is attached first, and then the end of the composite floor panel 60 is placed inside the beam formwork 62, 63 of the girder 20, and concrete is poured in this state. This makes it possible to reduce formwork materials and integrate the composite floor panel 60 and the girder 20, compared to constructing the reinforced concrete girder first and then joining the composite floor panel to this girder.
(3) The composite floor panel 60 is supported from below by the temporary beams 61, and in this state, a bottom formwork 62 and a side formwork 63 are erected along the side end surface 40B of the composite floor panel 60 and concrete is poured, thereby easily integrating the composite floor panel 60 and the main beam 20.
(4) The composite floor panel 60 is not manufactured at the construction site, but rather in a factory by forming H-shaped steel beams 30 from H-shaped steel or U-shaped steel material, joining wooden boards 40 to these steel beams 30, and then transporting them to the construction site, which can shorten the construction period.

Second Embodiment
FIG. 12 is a vertical cross-sectional view of a composite floor structure 1A according to a second embodiment of the present invention.
This embodiment differs from the first embodiment in that the floor of the current floor is a vibration-isolating double floor, and the ceiling of the floor below is a sound-insulating ceiling.
That is, three layers of reinforced gypsum boards 70 are laminated on the upper surfaces of the main beams 20, the steel beams 30, and the wooden boards 40, and support legs 71 are placed on the upper surfaces of these laminated reinforced gypsum boards 70, and flooring 72 is installed on top of the support legs 71.
Additionally, three layers of reinforced gypsum boards 80 are laminated on the undersides of the steel beams 30 and the wooden boards 40. Suspension bolts 81 are attached to the ceiling base 43, and the suspension bolts 81 extend downward, penetrating the reinforced gypsum boards 80. A ceiling material 82 is supported by the suspension bolts 81, and a sound-proofing material 83 is provided on the underside of the ceiling material 82.
According to this embodiment, there are the same effects as those (1) to (4) described above.

The present invention is not limited to the above-described embodiment, and modifications and improvements within the scope of the present invention that can achieve the object of the present invention are included in the present invention.
For example, in each of the above-mentioned embodiments, a temporary beam 61 is erected, a composite floor panel 60 is placed on top of this temporary beam 61, and then the bottom formwork 62 of the main girder 20 is erected, but this is not limited to the above. After the bottom formwork 62 of the main girder 20 is erected, the temporary beam 61 may be erected, and the composite floor panel 60 may be placed and the reinforcement of the main girder 20 may be performed.
In addition, in each of the above-described embodiments, the studs 35 are provided as protrusions on the webs 33 of the steel beams 30, but this is not limiting, and flat steel or shaped steel may be provided as the protrusions.
In addition, in each of the above-described embodiments, grout material 46 is injected into the recess 44 of the wooden board 40 through the grout injection hole 45 provided on the underside of the wooden board 40, and air is removed through the air vent hole 36. However, this is not limited to the above, and grout material 46 may be injected into the recess 44 of the wooden board 40 through the air vent hole 36 shown in FIG. 3, and air may be removed through the grout injection hole 45 shown in FIG. 3.

1, 1A... Composite floor structure 10... Column 20... Beam 21... Jaw 22... Beam main reinforcement 23... Stirrup 24... Pole reinforcement 25... Concrete body 30... Steel beam 31... Lower flange 32... Upper flange 33... Web 34... Support flange 35... Stud (protruding part) 36... Air vent hole 37... Bolt insertion hole 38... High strength bolt 39... Nut 40... Wood board 40A... Side end surface of wood board joined to steel beam 40B... Side end surface of wood board joined to girder (end of wood board not joined to steel beam)
Reference Signs List 41: CLT 42: Formwork plywood 43: Ceiling base 44: Recess 45: Grout injection hole 46: Grout material (filler) 47: Female thread 48: Bolt 50: Frame material 60: Composite floor panel 61: Temporary beam 62: Bottom formwork (beam formwork)
63...Side formwork (beam formwork)
70: Reinforced plaster board 71: Support leg 72: Floor material 80: Reinforced plaster board 81: Bolt 82: Ceiling material 83: Sound insulation material

Claims (3)

A composite floor structure having steel beams and wooden boards,
The steel beam includes upper and lower flanges extending horizontally and a web extending vertically connecting the upper and lower flanges,
The side end surface of the wood board is disposed in contact with the side surface of the web,
The wood board is configured to include CLT formed by laminating sawn boards,
The entire side end surface of the CLT wooden board is sandwiched between the upper and lower flanges,
The web of the steel beam is provided with a protruding portion protruding laterally,
A recess into which the protrusion is inserted is formed on the side end surface of the CLT of the wooden board,
A composite floor structure characterized in that the inside of the recess is filled with a filler material. Further comprising a reinforced concrete beam supporting the wooden board;
2. The composite floor structure according to claim 1, wherein the beams are joined at their ends to the steel beams and at their ends of the wooden boards that are not joined to the steel beams. A method for constructing a composite floor structure comprising steel beams, reinforced concrete beams, and wood planks, comprising the steps of :
The ends of the wooden boards are joined to the steel beams,
The end of the steel beam and the end of the wooden board that is not joined to the steel beam are joined to the reinforced concrete beam,
The steel beam includes a flange extending horizontally and a web extending vertically from the flange,
The side end surface of the wood board is disposed in contact with the side surface of the web,
The web of the steel beam is provided with a protruding portion protruding laterally,
A recess into which the protrusion is inserted is formed on a side end surface of the wood board,
The inside of the recess is filled with a filler,
A step of preparing a composite floor panel in which the steel beam and the wooden board are integrated, erecting a temporary beam, and placing the composite floor panel on the temporary beam;
erecting a beam formwork along the side end surface of the composite floor panel;
and pouring concrete inside the beam formwork to construct a beam integral with the composite floor panel.

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