Structure

Abstract

To provide a structure having a hybrid beam that includes a wooden beam and has high strength with high shear capacity.SOLUTION: A structure has a pair of columns, a wooden beam connected to the pair of columns, a first reinforced concrete and a second reinforced concrete, and a first reinforcement material and a second reinforcement material. The first reinforced concrete and the second reinforced concrete cover a first end and a second end of the wooden beam, respectively, and are disposed so as to expose the wooden beam between the first end and the second end. The first reinforcement material and the second reinforcement material cover lateral faces of the first end and the second end, respectively, and are embedded in the first reinforced concrete and the second reinforced concrete, respectively.SELECTED DRAWING: Figure 2B

Description

Technical Field

[0001] One embodiment of the present invention relates to a structure exemplified by a building or the like.

Background Art

[0002] In recent years, in a structure exemplified by a building such as an office building, a hospital, or a commercial facility that requires a large indoor space, a steel frame is used as a beam connecting a pair of columns, and both ends of the steel frame are covered with reinforced concrete (hybrid beam). By using a hybrid beam, the number of columns can be significantly reduced compared to the case where all beams are constructed with reinforced concrete, and as a result, a structure having a large space can be designed and built (see Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] [[ID=!]]<! One embodiment of the present invention aims to provide a structure including a hybrid beam containing a wooden beam. Alternatively, one embodiment of the present invention aims to provide a structure including a hybrid beam containing a wooden beam with high shear resistance.

Means for Solving the Problems

[0005] One embodiment of the present invention is a structure. This structure comprises a pair of columns, a wooden beam connected to the pair of columns, a first reinforced concrete and a second reinforced concrete, and a first reinforcing member and a second reinforcing member. The first and second reinforced concrete cover the first and second ends of the wooden beam, respectively, and are arranged so that the wooden beam is exposed between the first and second ends. The first and second reinforcing members cover the sides of the first and second ends, respectively, and are embedded in the first and second reinforced concrete, respectively. [Brief explanation of the drawing]

[0006] [Figure 1] A schematic perspective view of a structure which is one embodiment of the present invention. [Figure 2A] A schematic side view of a hybrid beam of a structure, which is one embodiment of the present invention. [Figure 2B] A schematic side view of a hybrid beam of a structure, which is one embodiment of the present invention. [Figure 3A] A schematic top view of a hybrid beam structure, which is one embodiment of the present invention. [Figure 3B] A schematic top view of a hybrid beam structure, which is one embodiment of the present invention. [Figure 4A] A schematic end view of a hybrid beam of a structure, which is one embodiment of the present invention. [Figure 4B] A schematic end view of a hybrid beam of a structure, which is one embodiment of the present invention. [Figure 5A] A schematic end view of a hybrid beam of a structure, which is one embodiment of the present invention. [Figure 5B] A schematic front view of a reinforcing material used in a hybrid beam of a structure, which is one embodiment of the present invention. [Figure 5C] A schematic front view of a reinforcing material used in a hybrid beam of a structure, which is one embodiment of the present invention. [Figure 6A] A schematic top view of a hybrid beam structure, which is one embodiment of the present invention. [Figure 6B]A schematic end view of a hybrid beam of a structure, which is one embodiment of the present invention. [Figure 7] A schematic top view of a hybrid beam structure, which is one embodiment of the present invention. [Modes for carrying out the invention]

[0007] The embodiments of the present invention will be described below with reference to the drawings and other drawings. However, the present invention can be implemented in various forms without departing from its spirit, and is not to be interpreted as being limited to the embodiments described below.

[0008] While drawings may schematically represent the width, thickness, shape, etc., of each part compared to the actual embodiment in order to clarify the explanation, these are merely examples and do not limit the interpretation of the present invention. In this specification and each figure, elements having the same function as those described with respect to previously shown figures are denoted by the same reference numeral, and redundant explanations may be omitted. When indicating a part of an element denoted by a reference numeral, a lowercase alphabet letter is added to the reference numeral. When indicating multiple elements having the same or similar structure separately, a hyphen and a natural number are added after the reference numeral. When indicating multiple elements having the same or similar structure collectively, only the reference numeral is used.

[0009] Hereinafter, the expression "one structure is exposed from another structure" means a part of one structure that is not covered by another structure, and this part that is not covered by another structure also includes a part that is covered by yet another structure.

[0010] Hereinafter, "concrete" refers to a substance in which the hydrate produced by the reaction of cement, one of the raw materials, with water hardens and does not exhibit fluidity. This is distinguished from a mixture containing cement and water that has not completely hardened and retains fluidity (ready-mixed concrete, fresh concrete).

[0011] The structure of structure 100, one embodiment of the present invention, will be described below. For convenience, in the drawings used in this description, the plane parallel to the horizontal ground surface will be considered the xy-plane, and the vertical direction perpendicular to the xy-plane will be considered the z-direction.

[0012] 1.Overall structure A schematic perspective view of the structure 100 is shown in Figure 1. As shown in Figure 1, the structure 100 basically consists of a plurality of columns 110 extending vertically (z direction), a plurality of beams 120 connected to a pair of columns 110 and extending horizontally (x direction or y direction), and a floor slab 150 provided on top of the beams 120. Each beam 120 is connected to an adjacent pair of columns 110.

[0013] At least one of the beams 120 provided in the structure 100 is a hybrid beam. All of the beams 120 provided in the structure 100 may be hybrid beams, or a part of the beams 120 may be hybrid beams, and the other beams 120 may be entirely made of reinforced concrete beams (reinforced concrete beams, hereinafter referred to as RC beams) or wooden beams. For example, in the structure 100 shown in FIG. 1, the first beam 120-1 and the third beam 120-3 are hybrid beams, and the second beam 120-2 and the fourth beam 120-4 are RC beams. Here, a hybrid beam is used as the beam 120 connected to a pair of columns 110 provided at long intervals (spans) (for example, the pair of the first column 110-1 and the second column 110-2, the pair of the third column 110-3 and the fourth column 110-4, the pair of the fifth column 110-5 and the sixth column 110-6), and an RC beam is used as the beam 120 connected to a pair of columns 110 provided at short intervals (for example, the pair of the first column 110-1 and the third column 110-3, the pair of the second column 110-2 and the fourth column 110-4, the pair of the third column 110-3 and the fifth column 110-5, the pair of the fourth column 110-4 and the sixth column 110-6). The arrangement of the hybrid beam and the RC beam can be arbitrarily determined, but as in the example shown in FIG. 1, it is preferable to use a hybrid beam between a pair of columns 110 provided at long intervals. This is because the hybrid beam is lighter than the RC beam, so by using the hybrid beam for beams with a large span (here, the first beam 120-1, the third beam 120-3, etc.), a large indoor space can be secured while imparting sufficient strength to the structure 100.

[0014] 2. Column Schematic side views of a pair of columns 110 (the first column 110-1, the second column 110-2) and the beam 120 connected thereto are shown in FIGS. 2A and 2B. In FIG. 2B, for showing the internal structure, the concretes 116 and 130 of the column 110 and the beam 120 are shown by dotted lines. Also, in FIGS. 2A and 2B, the floor slab 150 is not shown. The floor slab 150 is reinforced concrete provided on the beam 120, and since a known structure can be adopted, the description thereof is omitted.

[0015] There is no particular restriction as long as the number of columns 110 is 4 or more. The number and arrangement may be appropriately determined according to the size and shape of the structure 100. The column 110 is connected to a pile or a foundation beam not shown in the figure. The shape of the column 110 (end face shape in the xy plane) is also arbitrary and may be appropriately selected from a quadrangle, a circle, an ellipse, etc. The length of the column 110 is also appropriately designed according to the size of the structure 100 and the height of each floor.

[0016] Each column 110 is provided with a reinforcing bar unit including at least one column main reinforcing bar 112 extending in the vertical direction and a plurality of hoop bars 114 intersecting with the column main reinforcing bar 112 and provided so as to surround the column main reinforcing bar 112. Concrete 116 is placed so as to surround this reinforcing bar unit (FIG. 2B). The number of the column main reinforcing bars 112 and the arrangement density of the hoop bars 114 are also appropriately determined according to the length and thickness of the column 110 and the required strength.

[0017] 3. Hybrid beam As shown in FIGS. 2A and 2B, the beam 120 which is a hybrid beam includes a wooden beam 122 and a pair of reinforced concretes 124 (the first reinforced concrete 124-1 and the second reinforced concrete 124-2) which cover both ends of the wooden beam 122 respectively, are spaced apart from each other, and are arranged so as to expose the wooden beam 122 between both ends. The wooden beam 122 is connected to a pair of columns 110 via the reinforced concretes 124 arranged so as to embed both ends thereof. As will be described later, the reinforced concrete 124 includes various reinforcing bars connected to the column 110 and the concrete 130 covering both ends of the wooden beam 122 and the reinforcing bars.

[0018] The wooden beam 122 includes timber, and its end face shape (the end face perpendicular to the extension direction of the wooden beam 122) can be arbitrarily determined. The end face shape may be a polygon such as a circle, ellipse, or quadrilateral. Alternatively, the contour of the end face shape may be formed by multiple curves and multiple straight lines. Furthermore, the end face shape may be constant in the extension direction of the wooden beam 122, or it may change due to the original shape of the timber. There are no restrictions on the type of timber; for example, it may be timber derived from coniferous trees such as cypress, pine, and cedar, or timber derived from hardwoods such as oak, beech, zelkova, walnut, teak, and mahogany. In addition, the wooden beam 122 may be formed from plywood made by gluing together multiple plank-shaped pieces of timber.

[0019] Figure 3A shows a schematic side view centered on a single reinforced concrete structure 124. As shown in Figures 2B and 3A, each reinforced concrete structure 124 is equipped with multiple beam main reinforcements 126 and multiple lateral reinforcements 128.

[0020] The main beam reinforcement bars 126 extend in a direction parallel to the extension direction of the wooden beam 122 and are positioned above and below the wooden beam 122, spaced apart from the wooden beam 122 (see Figure 2B). A portion of the main beam reinforcement bars 126 is inserted into the reinforcement unit of the column 110, thereby fixing the main beam reinforcement bars 126 to the reinforcement unit of the column 110. On the other hand, an anchoring plate 126a with a larger end area than the main beam reinforcement bar 126 may be formed on the beam center side of each main beam reinforcement bar 126 (Figure 2B).

[0021] The lateral reinforcement bars 128 are arranged to intersect with the wooden beam 122 and the main beam reinforcement bars 126. As shown in the schematic diagram of the end face along the dashed line AA' in Figure 3A (Figure 4A), the lateral reinforcement bars 128 are arranged to surround the wooden beam 122 and the main beam reinforcement bars 126. The lateral reinforcement bars 128 may also be arranged to surround all of the main beam reinforcement bars 126. The arrangement density (pitch) of the lateral reinforcement bars 128 may be constant or not constant within the reinforced concrete 124. For example, the lateral reinforcement bars 128 may be arranged at a higher density on the column 110 side (i.e., the end side of the beam 120) and on the center side of the beam 120.

[0022] As shown in Figure 3B, multiple reinforcing bars 132 may be further placed in the reinforced concrete 124 as an arbitrary configuration. The reinforcing bars 132 may be placed so as to be in contact with the lateral reinforcing bars 128 or the main beam reinforcing bars 126. Although not shown, the reinforcing bars 132 are inverted U-shaped reinforcing bars that intersect the wooden beam 122 and two or more main beam reinforcing bars 126, enclosing part of the wooden beam 122 and the main beam reinforcing bars 126, and are positioned so that the U-shaped opening faces downwards. Each reinforcing bar 132 can be placed, for example, sandwiched between two adjacent lateral reinforcing bars 128 and in contact with one of the lateral reinforcing bars 128. The number, density, and length of the reinforcing bars 132 can also be determined arbitrarily.

[0023] The wooden beam 122 may be in contact with the column 110. More specifically, both ends of the wooden beam 122 may be in contact with the stirrups 114 of a pair of columns 110, or they may be in contact with the concrete 116 forming the column 110, or they may be embedded in the concrete 116. The wooden beam 122 is sandwiched between multiple beam main reinforcements 126 and surrounded by lateral reinforcements 128 and interlocking reinforcements 132.

[0024] The concrete 130 is provided to embed the main beam reinforcement 126, lateral reinforcement 128, and inserting reinforcement 132, along with both ends of the wooden beam 122. Each reinforced concrete 124 is composed of the main beam reinforcement 126, lateral reinforcement 128, and concrete 130. When inserting reinforcement 132 is used, the inserting reinforcement 132 also constitutes each reinforced concrete 124.

[0025] Here, as can be seen from Figures 2B, 3A, and 4A, each wooden beam 122 is provided with a reinforcing member 140. The reinforcing member 140 is in contact with the wooden beam 122 and covers at least the sides of both ends of the wooden beam 122. The reinforcing member 140 can be positioned so as to be embedded in the reinforced concrete 124. The length of the reinforcing member 140 (length in the direction in which the wooden beam 122 extends) may be the same as the length of the reinforced concrete 124, or it may be less than the length of the reinforced concrete 124. In the former case, the end face of the reinforcing member 140 is exposed from the reinforced concrete 124.

[0026] As shown in Figures 2B, 3A, and 4A, the reinforcing member 140 may include, for example, a pair of reinforcing plates that sandwich one end of the wooden beam 122. In this case, the pair of reinforcing plates cover both sides of the end of the wooden beam 122. As shown in Figure 3A, the width of the wooden beam 122 (a length perpendicular to the extension direction of the wooden beam 122 and parallel to the horizontal plane) may be the same throughout the wooden beam 122, or, as shown in Figure 3B, the width of the wooden beam 122 within the reinforced concrete 124 may be smaller than that of the portion exposed from the reinforced concrete 124. In the latter case, the side surface 122a of the portion of the wooden beam 122 exposed from the reinforced concrete 124 and the outer surface 140a of the reinforcing member 140 within the reinforced concrete 124 may be on the same plane.

[0027] As shown in Figure 4B, the reinforcing member 140 may include an upper reinforcing plate 140-3 that contacts and covers the upper surface of the wooden beam 122, together with a pair of reinforcing plates 140-1 and 140-2. The pair of reinforcing plates 140-1 and 140-2 and the upper reinforcing plate 140-3 are each independent parts and may be connected to each other by adhesive, welding, or fasteners such as bolts and nuts, or the pair of reinforcing plates 140-1 and 140-2 and the upper reinforcing plate 140-3 may be a single integrated part.

[0028] Alternatively, as shown in Figure 5A, the reinforcing member 140 may include a lower reinforcing plate 140-4 that contacts and covers the lower surface of the wooden beam 122, together with a pair of reinforcing plates 140-1 and 140-2 and an upper reinforcing plate 140-3. That is, each reinforcing member 140 may have a tubular shape and be configured to surround the end of the wooden beam 122. The pair of reinforcing plates 140-1 and 140-2 and the lower reinforcing plate 140-4 are each independent parts and may be connected to each other by adhesive, welding, or fasteners such as bolts and nuts, or the pair of reinforcing plates 140-1 and 140-2 and the lower reinforcing plate 140-4 may be integrated. Therefore, the pair of reinforcing plates 140-1 and 140-2, the upper reinforcing plate 140-3, and the lower reinforcing plate 140-4 may also be integrated to form a single tubular reinforcing member 140.

[0029] The pair of reinforcing plates 140-1, 140-2, the upper reinforcing plate 140-3, and the lower reinforcing plate 140-4 that constitute the reinforcing member 140 are each plate-shaped members and can be formed from, for example, steel plates containing iron, as shown in Figure 5B. Alternatively, the pair of reinforcing plates 140-1, 140-2, the upper reinforcing plate 140-3, and the lower reinforcing plate 140-4 may be plate-shaped members formed from resins containing fibers such as carbon fibers, glass fibers, aramid fibers, basalt fibers, flax fibers, and cellulose fibers (fiber-reinforced plastics). The thickness of the reinforcing member 140, that is, the thickness of each of the pair of reinforcing plates 140-1, 140-2, the upper reinforcing plate 140-3, and the lower reinforcing plate 140-4, can be appropriately set according to the shear strength required for the beam 120, and can be appropriately selected within the range of 1 mm to 20 mm, or 3 mm to 15 mm. Furthermore, as shown in Figure 5C, the plate-like members may have a mesh shape with multiple openings 140b arranged at a constant pitch. These plate-like members are fixed to the wooden beam 122 with adhesive or fasteners such as bolts and nuts.

[0030] Wood has less strength compared to steel. Therefore, compared to conventional hybrid beams formed of steel and reinforced concrete covering both ends, hybrid beams using wooden beams have lower shear strength and are more susceptible to shear failure. When a load is applied to the hybrid beam in the vertical direction, a large shear stress is generated in the section where reinforced concrete is placed (RC section), especially at the end opposite the column 110 in the RC section, and when the shear force exceeds the shear strength, the beam 120 will fail by shear. However, in the beam 120 according to the embodiment of the present invention, a reinforcing member 140 is provided on the wooden beam 122 to supplement the shear strength of the wooden beam 122. Therefore, the beam 120 can have high shear strength. Accordingly, by applying the embodiment of the present invention, a highly earthquake-resistant structure can be constructed.

[0031] Furthermore, by using wooden beams instead of steel frames, it is possible to construct a hybrid beam with superior design. Since a portion of the wooden beams 122 that make up beam 120 are exposed from the concrete 130, the warmth inherent in wood can be provided to the interior, and a relaxing effect can be obtained. Moreover, since wood is a product of carbon dioxide fixation through plant photosynthesis, applying the embodiments of the present invention can contribute to the reduction of carbon dioxide, a greenhouse gas.

[0032] 4. Variations In the example described above, the reinforcing member 140 is composed of multiple plate-shaped members, but the structure of the reinforcing member 140 is not limited to this. For example, as shown in the schematic top view of Figure 6A and the schematic end face along the dashed line BB' of Figure 6A (Figure 6B), the reinforcing member 140 provided in each reinforced concrete 124 may include multiple linear members. Each linear member may have a closed shape without both ends, as shown in Figure 6B, or it may have both ends. The multiple linear members are arranged in the reinforced concrete 124 so as to be in contact with the ends of the wooden beams 122 and surround the ends of the wooden beams 122. For this reason, the multiple linear members constituting the reinforcing member 140 are configured to be plastically or elastically deformable so as to conform to the shape of the wooden beams 122. In each wooden beam 122, the arrangement density of the multiple linear members may be constant or not. For example, the arrangement density may be high on the column 110 side and on the central side of the beam 120, and low in between these areas.

[0033] Even if the reinforcing member 140 includes multiple linear members, each linear member can include iron. Therefore, for example, high-tensile steel wire (PC steel wire) can be used as a linear member. The diameter of the end face of the linear member can also be appropriately determined according to the shear strength required for the beam 120, and can be selected within the range of 10 mm to 30 mm, for example.

[0034] Alternatively, as shown in Figure 7, the reinforcing member 140 provided on each wooden beam 122 may include a plurality of belt-shaped members. Similar to the case where the reinforcing member 140 includes a plurality of linear members, each belt-shaped member may have a closed shape without ends, or it may have both ends. Furthermore, the plurality of belt-shaped members are arranged in the reinforced concrete 124 to be in contact with the ends of the wooden beam 122 and to surround the ends of the wooden beam 122. For this reason, the plurality of belt-shaped members constituting the reinforcing member 140 are configured to be plastically or elastically deformable so as to conform to the shape of the wooden beam 122. In each wooden beam 122, the arrangement density of the plurality of belt-shaped members may be constant or not. For example, the arrangement density may be high on the column 110 side and on the central side of the beam 120, and low in between these areas.

[0035] The belt-shaped member may contain iron, or it may contain the fiber-reinforced plastic described above. The width of the belt-shaped member (length in the direction in which the beam 120 extends) can be appropriately determined according to the shear strength required for the beam 120, and can be selected from, for example, a range of 10 mm to 200 mm or 20 mm to 100 mm. The thickness of the belt-shaped member can be, for example, 5 mm to 20 mm. Furthermore, the belt-shaped member may also have a mesh shape with multiple openings.

[0036] In the above modified example, the shear strength of the wooden beam 122, which is lower than that of a steel frame, can be compensated for by the reinforcing material 140, which is composed of multiple linear or belt-shaped members. As a result, a high shear strength comparable to that of a hybrid beam including a steel frame can be achieved in the beam 120.

[0037] The embodiments described above as examples of the present invention can be combined and implemented as appropriate, insofar as they do not contradict each other. Additions, deletions, or design modifications of components based on these embodiments, made by those skilled in the art, are also included within the scope of the present invention, as long as they retain the essence of the invention.

[0038] Any effects or benefits other than those brought about by the embodiments described above, if they are clear from the description herein or easily predictable to those skilled in the art, are naturally understood to be brought about by the present invention. [Explanation of symbols]

[0039] 100: Structural element, 110: Column, 110-1: First column, 110-2: Second column, 110-3: Third column, 110-4: Fourth column, 110-5: Fifth column, 110-6: Sixth column, 112: Main column reinforcement, 114: Stirrups, 116: Concrete, 120: Beam, 120-1: First beam, 120-2: Second beam, 120-3: Third beam, 120-4: Fourth beam, 122: Wooden beam, 122a: Side view, 124: Reinforced concrete, 124-1: First reinforced concrete, 124-2: Second reinforced concrete, 126: Main beam reinforcement, 126a: Anchorage plate, 128: Lateral reinforcement, 130: Concrete, 132: Insertion bars, 140: Reinforcement material, 140-1: Reinforcement plate, 140-2: Reinforcement plate, 140-3: Upper reinforcement plate, 140-4: Lower reinforcement plate, 140a: Outer surface, 140b: Opening, 150: Floor slab

Claims

1. A pair of pillars, Wooden beams connected to the aforementioned pair of columns, A first reinforced concrete and a second reinforced concrete are arranged to cover the first and second ends of the wooden beam, respectively, and to expose the wooden beam between the first and second ends, and A structure comprising a first reinforcing member and a second reinforcing member that cover the sides of the first end and the second end, respectively, and are embedded in the first reinforced concrete and the second reinforced concrete, respectively.

2. The structure according to claim 1, wherein the first reinforcing member and the second reinforcing member each include a pair of reinforcing plates that sandwich the first end and the second end, respectively.

3. The structure according to claim 2, wherein the first reinforcing member and the second reinforcing member each further include an upper reinforcing plate that covers the upper surface of the first end and the second end, respectively.

4. Each of the first and second reinforcing members has a tubular shape. The structure according to claim 1, wherein the first reinforcing member and the second reinforcing member surround the first end and the second end, respectively.

5. Each of the first and second reinforcing members includes a plurality of linear or belt-shaped members. The structure according to claim 1, wherein the plurality of linear members or belt-shaped members of the first reinforcing member and the plurality of linear members or belt-shaped members of the second reinforcing member each surround the first end and the second end.

6. The structure according to claim 1, wherein the first reinforcing material and the second reinforcing material include iron or a fiber-containing resin.

7. The structure according to claim 1, wherein the first reinforcing member and the second reinforcing member have a mesh shape.

8. The structure according to claim 1, wherein the first reinforcing member and the second reinforcing member are in contact with the first end and the second end, respectively.

9. The first reinforced concrete extends from one side of the pair of columns in the direction in which the wooden beam extends, The structure according to claim 1, wherein the second reinforced concrete extends in the direction from the other side of the pair of columns.

10. The structure according to claim 1, wherein the wooden beam is connected to the side surfaces of the pair of columns.

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