JP7548826B2 - Wall - Google Patents

Description

The present invention relates to a wall body.

In recent years, the use of wood materials in buildings has been recommended from the perspective of reducing environmental impact. Patent Document 1 proposes a structure in which concrete pillars are fireproofed with wood covering material to prevent the concrete pillars from exploding in the event of a fire.

On the other hand, earthquake-resistant walls, which are structural elements that bear earthquake forces, are generally constructed of reinforced concrete (RC) (RC earthquake-resistant walls).

JP 2020-16044 A

However, using reinforced concrete earthquake-resistant walls creates a strong feeling of claustrophobia inside the building, and from the perspective of the building's aesthetics, it is desirable for the earthquake-resistant walls to be covered with wood materials. In Patent Document 1, a special device is used to rotate a rod-shaped concrete pillar while wrapping a strip of wood covering material around it, but it is not practical to apply this method to planar walls.

In addition, with normal earthquake-resistant walls, the wall construction requires processes such as reinforcing bars, setting formwork, pouring concrete, and removing the formwork, which makes construction complicated and increases costs.

The present invention was made in consideration of the above-mentioned problems, and its purpose is to provide a wall structure that is easy to construct and has a beautiful appearance.

In order to achieve the above-mentioned object, the present invention provides a wall comprising: a plate-shaped embedded formwork made of a wood material; a plate-shaped concrete member provided inside two of the embedded formworks ; and a plurality of wooden beams provided at intervals in the vertical direction between the two embedded formworks, the wall being characterized in that horizontal reinforcement bars embedded in the concrete are arranged between the plurality of beams .

In the present invention, by using wooden boards as embedded formwork for concrete members in walls such as earthquake-resistant walls, the surface of the wall is exposed to the wood, reducing the sense of claustrophobia and creating an aesthetically pleasing appearance. The wall can be easily constructed because the form stripping process required in normal wall construction is no longer necessary. In addition, the wall can be made lighter because some of the concrete members are replaced with wooden beams, and the beams make it easier to control the installation accuracy of the embedded formwork.

It is also preferable that the two buried formwork pieces are connected by a connecting material.
For the interior walls of buildings, it is particularly preferable to have exposed wood on both sides of the wall for aesthetic reasons. In this case, by connecting two embedded forms sandwiching a concrete member with a connecting material, the connecting material can resist the lateral pressure applied to the embedded forms when concrete is poured between the two embedded forms, and maintain the distance between the embedded forms. In addition, the embedded formwork can be expected to improve the strength and toughness of the wall by restraining the concrete member.

It is desirable that the wall has shear reinforcement for integrating the buried formwork and the concrete member.
This integrates the buried formwork and the concrete member, improving the out-of-plane rigidity of the wall and suppressing its out-of-plane deformation.

The present invention provides walls and other structures that are easy to construct and have a beautiful appearance.

FIG. FIG. 2 is a diagram showing a method of constructing a seismic wall 1. A diagram showing a bolt 6 and a nut 7. A diagram showing the drift pin 8, the rods 9, 9a, the cotter 45, and the coupler 10. An example of the placement of earthquake-resistant walls 1. FIG. An example in which a cotter 45 and a bar 46 are provided on the end surface of an embedded formwork 4. A diagram showing tension member 47. A diagram showing bundle material 49.

The following describes in detail a preferred embodiment of the present invention with reference to the drawings.

Figure 1 shows a seismic wall 1 according to an embodiment of the wall of the present invention. Figure 1(a) is an elevational view of the seismic wall 1, and Figure 1(b) is a horizontal cross-sectional view taken along line A-A in Figure 1(a).

As shown in Figure 1, the earthquake-resistant wall 1 is placed within a structural plane surrounded by columns 2 and beams 3. The columns 2 and beams 3 are reinforced concrete members, but they may also be steel members.

The earthquake-resistant wall 1 includes an embedded formwork 4, a concrete member 5, bolts 6, nuts 7, etc.

The buried formwork 4 is a plate-like member made of wood materials such as CLT (Cross Laminated Timber), LVL (Laminated Veneer Lumber), and laminated timber, and bears earthquake forces together with the concrete member 5. In this embodiment, two buried formworks 4 are arranged with their plate surfaces facing each other. Furthermore, by designing the columns 2 to bear long-term loads, the buried formwork 4 does not need to be treated as a member that requires long-term load bearing, and the fire-resistant coating required for this member is not required.

Here, CLT is particularly suitable for use as the embedded formwork 4. In other words, external forces such as earthquakes have positive and negative forces and are not forces that come from one direction. For this reason, CLT is superior as a material for the embedded formwork 4 to regular wood materials, which are anisotropic materials with high strength in the fiber direction and low strength in the direction perpendicular to the fiber. CLT is superior because it reduces the difference in properties between directions by laminating and gluing wood pieces so that the fiber directions are perpendicular to each other.

The concrete members 5 are plate-shaped members that are placed inside the two buried formwork 4. In the earthquake-resistant wall 1 of this embodiment, the buried formwork 4 bears the earthquake force, so the thickness of the concrete members 5 can be made thinner than that of a typical earthquake-resistant wall, and the amount of concrete can be reduced, reducing the environmental load and weight. However, since the concrete members 5 are the main earthquake-resistant element of the earthquake-resistant wall 1, the concrete members 5 are generally thicker than the buried formwork 4. However, it is also possible to make the concrete members 5 thinner than the buried formwork 4 in consideration of the environment and the weight of the earthquake-resistant wall 1.

The concrete member 5 is made by embedding horizontal bars 52 and vertical bars 53 as reinforcing bars in concrete 51. The horizontal bars 52 are horizontal reinforcing bars arranged parallel to the embedded formwork 4, and multiple bars are provided at intervals in the vertical direction. The vertical bars 53 are vertical reinforcing bars, and multiple bars are provided at intervals in the horizontal direction along the horizontal bars 52.

These reinforcing bars are arranged as single reinforcements, and the horizontal bars 52 are arranged in only one row in the plane. The multiple vertical bars 53 are arranged alternately on both buried formwork 4 sides of the horizontal bars 52. By arranging the vertical bars 53 in a staggered pattern in this way, out-of-plane deformation of the earthquake-resistant wall 1 can be suppressed against compressive forces applied to the earthquake-resistant wall 1 during an earthquake, etc., compared to when the vertical bars 53 are arranged only on one side of the horizontal bars 52. It is also possible to arrange multiple horizontal bars 52 on the top and bottom alternately on both buried formwork 4 sides of the vertical bars 53.

The bolts 6 and nuts 7 (hereinafter sometimes referred to as bolts 6, etc.) are connecting members that connect two pieces of embedded formwork 4, and the bolts 6 also function as shear reinforcement between the embedded formwork 4 and the concrete member 5. In other words, the bolts 6 resist the shear force that occurs between the embedded formwork 4 and the concrete member 5 when the earthquake-resistant wall 1 undergoes out-of-plane deformation, thereby structurally integrating the embedded formwork 4 and the concrete member 5, improving the out-of-plane rigidity of the earthquake-resistant wall 1 and suppressing its out-of-plane deformation. Multiple bolts 6, etc. are arranged at intervals in the horizontal and vertical directions.

Figure 2 shows a method for constructing an earthquake-resistant wall 1. In this embodiment, after arranging the reinforcing bars (horizontal bars 52 and vertical bars 53) of the concrete member 5 of the earthquake-resistant wall 1 and the reinforcing bars 21 of the column 2 as shown in Figure 2(a), the column 2 is constructed as shown in Figure 2(b). As mentioned above, the column 2 is an RC member, and is constructed by placing formwork (not shown) around the reinforcing bars 21 and pouring concrete into it.

In this embodiment, two embedded forms 4 are then placed facing each other between the columns 2 as shown in FIG. 2(c). Here, as shown in FIG. 3(a), the two embedded forms 4 are provided with through holes 41 for passing the shafts of the headed bolts 6. The shafts of the bolts 6 are passed through the through holes 41 of both embedded forms 4 from one embedded form 4 side, and the nuts 7 are fastened to the tips of the shafts protruding from the through holes 41 of the other embedded form 4, thereby connecting the two embedded forms 4 as shown in FIG. 3(b). The heads and nuts 7 of the bolts 6 are accommodated in recesses 42 provided on the outer surface of the embedded form 4. However, the heads and nuts 7 of the bolts 6 may be connected in a form that protrudes (not shown) outside the wall surface of the embedded form 4.

Figure 2(d) shows the state in which the two buried forms 4 are connected by the bolts 6 and nuts 7. After this, concrete 51 is poured inside the two buried forms 4 to construct the earthquake-resistant wall 1 shown in Figure 1. The bolts 6 and the like resist the lateral pressure applied to the buried forms 4 when the concrete 51 is poured, and maintain the spacing between the buried forms 4. The buried forms 4 are left in place even after the concrete 51 hardens, as permanent forms that also serve as surface finishing materials.

Note that the embedded formwork 4 may not be in direct contact with the columns 2 or beams 3 (there may be a small gap between the embedded formwork 4 and the columns 2 or beams 3), and in such cases, a backing plate may be placed from the outside in the gap and concrete 51 may be poured.

As described above, in this embodiment, by using wooden boards as the embedded formwork 4 for the concrete members 5 in the earthquake-resistant wall 1, the surface of the earthquake-resistant wall 1 is exposed to the wood, reducing the feeling of claustrophobia and creating an aesthetically pleasing appearance. In addition, the form stripping process that is required in normal wall construction is no longer necessary, making the earthquake-resistant wall 1 easy to construct.

Furthermore, by having the buried formwork 4 bear the seismic force, the rigidity and strength of the earthquake-resistant wall 1 are improved. As a result, the amount of concrete in the earthquake-resistant wall 1 can be reduced, which is environmentally friendly and allows the earthquake-resistant wall 1 to be made lighter. In addition, because the concrete members 5 are covered by the buried formwork 4, the aesthetic appearance of the earthquake-resistant wall 1 is not marred even if cracks occur in the concrete members 5 during an earthquake, and water intrusion into the cracks and the associated corrosion of the reinforcing bars can be prevented.

In addition, in this embodiment, by placing a concrete member 5 between two embedded formworks 4 to form the earthquake-resistant wall 1, both sides of the earthquake-resistant wall 1 are exposed to wood, which creates a particularly attractive appearance when the earthquake-resistant wall 1 is used as an interior wall of a building.

The bolts 6 and the like resist the lateral pressure applied to the embedded formwork 4 when concrete 51 is poured between the two embedded formworks 4, and maintain the distance between the embedded formworks 4. In addition, the embedded formwork 4 restrains the concrete members 5, which is expected to improve the strength, toughness, etc. of the earthquake-resistant wall 1.

The bolts 6 also function as shear reinforcement between the buried formwork 4 and the concrete member 5. In other words, when compressive forces act on the earthquake-resistant wall 1 from the columns 2 and beams 3 due to earthquake forces or long-term building loads, shear (shift) may occur at the interface between the buried formwork 4 and the concrete member 5 due to out-of-plane deformation of the earthquake-resistant wall 1. However, by using the bolts 6 as shear reinforcement to resist this shear, the buried formwork 4 and the concrete member 5 are integrated, the out-of-plane rigidity of the earthquake-resistant wall 1 is improved, and the out-of-plane deformation can be suppressed.

Furthermore, if there is a gap between the buried formwork 4 and the columns 2 or beams 3, the bolts 6 are effective in transmitting the seismic force applied to the concrete member 5 to the buried formwork 4 and relieving the stress in the concrete member 5.

However, in cases where shear between the buried formwork 4 and the concrete member 5 is not an issue, or where the buried formwork 4 is in direct contact with the columns 2 and beams 3, the bolts 6 can be omitted. In this case, when pouring the concrete 51, a temporary support material (not shown) is provided on the outside of the buried formwork 4 to support the lateral pressure applied to the buried formwork 4 and maintain the spacing of the buried formwork 4. Alternatively, a separator or the like may be used as a connecting material to connect the buried formwork 4.

In this embodiment, the reinforcing bars of the concrete member 5 are single-bar arrangement, which reduces the labor and costs involved in the bar arrangement work, makes it easier to ensure the cover thickness of the reinforcing bars, and is also effective in preventing corrosion of the reinforcing bars. For normal RC earthquake-resistant walls with a wall thickness of 200 mm or more, double reinforcement is recommended, but in the earthquake-resistant wall 1 of this embodiment, single reinforcement can be achieved by increasing the diameter of the horizontal bars 52 and vertical bars 53, even if the thickness of the concrete member 5 is 200 mm or more.

However, the present invention is not limited to the above embodiment. For example, in this embodiment, bolts 6 are used as connecting members and shear reinforcement members for the buried formwork 4, but drift pins 8 may also be used as shear reinforcement members, as shown in FIG. 4(a).

In this case, a through hole 43 is provided in one of the two embedded formwork sheets 4 and a recess 44 is provided in the other, and the drift pin 8 is inserted into the through hole 43 and pushed toward the recess 44, so that the tip of the drift pin 8 is positioned in the recess 44 and the base end of the drift pin 8 is positioned in the through hole 43. After that, the remaining space 431 of the through hole 43 can be blocked with a plug (not shown).

The drift pin 8 may be placed after the two embedded formwork 4 are set, but it is also possible to set both embedded formwork 4 with the drift pin 8 already inserted into the through hole 43 of one embedded formwork 4, and then push the drift pin 8 into the recess 44 of the other embedded formwork 4.

Other shear reinforcement materials may include rods (dowels) 9 protruding inward from the embedded formwork 4 as shown in Figure 4(b), or the tips of rods 9a may be enlarged as shown in Figure 4(c).

Furthermore, as shown in FIG. 4(d), cotters (recesses) 45 may be formed on the inner surfaces of the two embedded formwork 4. In this case, the embedded formwork 4 and the concrete member 5 are integrated by the concrete 51 entering the cotters 45 of the embedded formwork 4.

Also, as shown in FIG. 4(e), threaded rebar or metric screws may be used as the rods 9, and the tips of the rods 9 protruding from the two embedded formwork 4 may be screwed into couplers 10 to connect the rods 9 to each other via the couplers 10. In this case, the rods 9 and couplers 10 also function as connecting members for the embedded formwork 4, and the embedded formwork 4 can also be expected to have a restraining effect on the concrete member 5.

In this embodiment, one embedded formwork 4 is arranged in an elevation view within the structural surface bounded by the columns 2 and beams 3, but as shown in FIG. 5(a), multiple embedded formworks 4 (two in the illustrated example) may be arranged side by side within the structural surface. Furthermore, as shown in FIG. 5(b), the strength can be improved by arranging earthquake-resistant walls 1 on the upper and lower floors of the building and fastening these earthquake-resistant walls 1 with prestress introduced by PC steel bars 11.

In addition, in the case of a wall structure, the entire circumference of the earthquake-resistant wall 1 does not have to be surrounded by columns 2 and beams 3; for example, a column 2 may be provided at only one end of the earthquake-resistant wall 1 in its plane. The earthquake-resistant wall 1 may also be provided so as to intersect in an L-shape in plan view as shown in FIG. 5(c), or so as to intersect in a cross shape in plan view. Furthermore, openings can be provided in the earthquake-resistant wall 1, and they can be used as windows or entrances. Reinforcement materials for the openings can also be provided in the earthquake-resistant wall 1 as necessary.

In this embodiment, the concrete member 5 is made of reinforced concrete, but as in the case of the earthquake-resistant wall 1a in FIG. 6(a), the horizontal reinforcement 52 and vertical reinforcement 53 may be omitted and the concrete member 5a may be made of unreinforced concrete. In this embodiment, the concrete member 5a can be made thin by having the buried formwork 4 bear the earthquake force, but in the earthquake-resistant wall 1a, the buckling prevention effect of the buried formwork 4 compensates for the thinness of the member. Also, unreinforced concrete is prone to cracking, but covering it with the buried formwork 4 maintains its aesthetic appearance. The concrete used for the concrete member 5a may be made of fiber-reinforced concrete to improve toughness.

In addition, in this embodiment, the concrete member 5 is provided inside the two embedded formwork 4, but as in the earthquake-resistant wall 1b in Figure 6 (b), one of the two embedded formwork 4 may be omitted and the concrete member 5 may be provided to the side of one embedded formwork 4.

For example, when applying an earthquake-resistant wall to the exterior wall of a building, if one side must be made of fire-resistant material due to restrictions in fire-resistance specifications, concrete 51 can be poured between the embedded formwork 4 and the normal formwork, and the normal formwork can be removed to leave one side of the concrete member 5 made of fire-resistant material, as shown in Figure 6(b). In the example of Figure 6(b), the bar material 9 (see Figure 4(b)) described above is used as shear reinforcement between the embedded formwork 4 and the concrete member 5.

In this embodiment, the end faces of the buried formwork 4 are left flat and untreated, but adhesives, dowels, cotters, etc. may be used on the end faces of the buried formwork 4 that face the columns 2 or beams 3, or on the end faces of adjacent buried formwork 4 when buried formwork 4 are placed side by side as in Figure 5(a), to resist shear forces between the members.

When using adhesive, the adhesive can be applied not only to the end face of the embedded formwork 4, but also between the end face of the embedded formwork 4 and the column 2 or beam 3, or between the end faces of adjacent embedded formwork 4, and the adhesive can be pressed into the gap.

Figure 7(a) shows an example in which a cotter 45 is formed on the end surface, where the end surface of an adjacent buried formwork 4 is cut into an uneven shape to provide a cotter 45, and the unevenness of both end surfaces is interlocked with each other.

Figure 7 (b) shows an example of using a dowel and a cotter together, where a cotter 45 is formed on the end surface of the buried formwork 4 facing the beam 3, and a bar (dowel) 46 is fixed to the buried formwork 4 so that it protrudes from the bottom surface of the cotter 45 toward the beam 3. A lag screw bolt or the like can be used for the bar 46. A filler such as post-cast mortar 12 is poured between the end surface of the buried formwork 4 and the beam 3, and the protruding part of the bar 46 is embedded in the post-cast mortar 12.

Figure 7 (b) shows an example of the end surface of the buried formwork 4 facing the beam 3, but it is also possible for the end surface of the buried formwork 4 facing the column 2 to have a similar configuration, and it is also possible for both the end surface facing the column 2 and the end surface facing the beam 3 to have a similar configuration.

As shown in FIG. 8(a), tension members 47 may be provided across the embedded formwork 4 and the beam 3. For example, reinforcing bars or bolts may be used as the tension members 47. In the example of FIG. 8(a), the tension members 47 are placed at four locations in total, at both ends of the top and bottom edges of the earthquake-resistant wall 1.

When an interlayer shear force acts on the earthquake-resistant wall 1 as shown by arrow a in FIG. 8(a) due to an earthquake or the like, a rotational moment is generated in the earthquake-resistant wall 1, which generates a tensile force in the direction that separates the embedded formwork 4 and the beam 3 at one end of the upper or lower side of the earthquake-resistant wall 1 as shown by arrow b. When an interlayer shear force acts on the earthquake-resistant wall 1 in the opposite direction as shown by arrow a', a rotational moment in the opposite direction is generated in the earthquake-resistant wall 1, which generates a tensile force in the direction that separates the embedded formwork 4 and the beam 3 at the other end of the upper or lower side of the earthquake-resistant wall 1 as shown by arrow b'. The tension member 47 resists these tensile forces and can improve the strength of the earthquake-resistant wall 1.

If the beam 3 is an RC member, the tension member 47 is embedded in the end face of the embedded formwork 4 and in the concrete of the beam 3. If the beam 3 is a steel member, the shaft of a headed bolt, which is the tension member 47, is passed through a hole formed in the flange of the beam 3 (H-shaped steel) as shown in Figure 8 (b), and the tip of the shaft is screwed into a female screw 48 embedded in the end face of the embedded formwork 4.

As shown in FIG. 9(a), a wooden beam 49 may be provided to connect two embedded forms 4. This allows a portion of the concrete member 5 between the embedded forms 4 to be replaced with the beam 49, reducing the weight of the earthquake-resistant wall 1. The beam 49 also makes it easier to control the installation accuracy of the embedded forms 4.

The beams 49 are columnar members, and are arranged, for example, over the entire height of the buried formwork 4. In addition, multiple beams 49 may be provided at intervals in the horizontal direction parallel to the buried formwork 4.

CLT is particularly suitable for use as the bundle 49. In other words, during an earthquake, compressive forces may be applied diagonally within the plane of the seismic wall 1. In this case, if normal wood materials, which are anisotropic materials, are used, forces will also be applied in the direction perpendicular to the fibers, which has low strength, making it more likely that strength and rigidity will decrease. On the other hand, as mentioned above, CLT does not have anisotropy, so using CLT for the bundle 49 can prevent the above-mentioned decrease in strength and rigidity.

In the example of FIG. 9(a), horizontal through holes 491 are provided in the columnar beams 49 along the beams 52 to allow the beams 52 to pass through, but the beams 49 may be provided at intervals in the vertical direction as shown in FIG. 9(b). The beams 52 can be arranged to pass between the upper and lower beams 49. Note that the concrete 51 is not shown in FIGS. 9(a) and (b).

The buried formwork 4 and the beams 49 are connected using adhesives, bolts, drift pins, screws, etc. When constructing the earthquake-resistant wall 1, one of the buried formworks 4 may be set at the position of the earthquake-resistant wall 1, and then the beams 49 may be attached to that buried formwork 4, or one buried formwork 4 with the beams 49 attached in advance may be set at the position of the earthquake-resistant wall 1.

Furthermore, as shown in Figure 9(c), two embedded formwork 4 connected with a beam 49 can be used as a precast member, which can then be transported to the construction site and set in place at the seismic wall 1. This is also true for cases where bolts 6, etc. are used as in Figure 1, where drift pins 8 are used as in Figure 4(a), and where rods 9 are connected with couplers 10 as in Figure 4(e), and precasting makes it easier to construct the seismic wall 1.

The earthquake-resistant wall 1 can also be precast, including the concrete members 5 between the buried formwork 4, making construction of the earthquake-resistant wall 1 even easier. In this embodiment, the amount of concrete can be reduced by having the buried formwork 4 bear the seismic force, making the earthquake-resistant wall 1 lighter. Therefore, even if the concrete members 5 are precast, there will be no problems with transportation or installation. However, considering the weight, the earthquake-resistant wall 1 can be precast by dividing it vertically or horizontally, and the precast members can be combined on-site to construct the earthquake-resistant wall 1. This is also true when the parts other than the concrete members 5 are precast, as shown in Figure 9(c).

The above describes preferred embodiments of the present invention with reference to the attached drawings, but the present invention is not limited to these examples. It is clear that a person skilled in the art can come up with various modified or revised examples within the scope of the technical ideas disclosed in this application, and it is understood that these also naturally fall within the technical scope of the present invention.

1, 1a, 1b: Earthquake-resistant wall 2: Column 3: Beam 4: Buried formwork 5, 5a: Concrete member 6: Bolt 7: Nut 8: Drift pin 9, 9a, 46: Bar 10: Coupler 11: PC steel bar 12: Post-cast mortar 21: Reinforcement bar 41, 43, 491: Through hole 42, 44: Recess 45: Cotter 47: Tensile material 48: Female screw 49: Bundle 51: Concrete 52: Horizontal bar 53: Vertical bar

Claims (3)

A plank-shaped embedded formwork made of wood material;
A plate-shaped concrete member provided inside the two embedded formworks;
A plurality of wooden bundles are provided at intervals in the vertical direction between the two embedded formworks;
Equipped with
A horizontal bar to be embedded in concrete is disposed between the plurality of beams.
A wall body characterized by: 2. The wall structure according to claim 1, wherein the two embedded formworks are connected by a connecting material. 3. The wall structure according to claim 1, further comprising a shear reinforcement material for integrating the buried formwork and the concrete member.

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