Wall structure of simple structure

Abstract

To provide a wall structure of a simple structure that can improve horizontal strength by preventing buckling of wall panels caused by in-plane shear force.SOLUTION: Two vertical members stand horizontally spaced apart. An upper frame is placed between the upper ends of the vertical members, and a lower frame is placed between the lower ends. A wall panel is fitted into the space enclosed by the vertical members, upper frame, and lower frame, and four reinforcements are installed at each of the four corners of the space. Each reinforcement is triangular, with one side extending along one of the two vertical members and the other side extending along either the upper or lower frame. The distance between the surface of each corner of the wall panel and the plate surface of each reinforcement is set so that when the wall panel is subjected to a horizontal force parallel to the wall surface and the corner of the wall panel deforms out of plane, the surface of the corner comes into contact with the plate surface of the reinforcement.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a simple structure having walls, and more particularly to the wall structure thereof. [Background technology]

[0002] "Simple structures" refer to architectural structures that are relatively simple in structure and easy to construct. Among simple structures, those commonly known as having walls include storerooms, warehouses, garages, containers, etc. These walls are usually composed of one or more wall structures. "Wall structures" refer to the combination of building materials necessary to form a wall, such as columns, cross members, and wall boards (also called wall panels).

[0003] Naturally, the wall structure of a simple structure is also required to have horizontal strength appropriate for a building material. "Horizontal strength" refers to the strength of a building material against horizontal forces (hereinafter referred to as "horizontal forces") that the building material is subjected to, such as wind pressure and earthquake forces. Conventional methods for improving the horizontal strength of the wall structure of a simple structure include, for example, providing vertical ribs on the surface of the wall panel, i.e., the wall surface, and inserting braces along the diagonals of the rectangular frame (hereinafter referred to as the "frame") formed by vertical and horizontal members.

[0004] For example, in the wall structure disclosed in Patent Document 1, the wall panel includes vertical ribs, reinforcing ribs within the plane, and connecting ribs on both the left and right edges. These vertical ribs prevent out-of-plane deformation such as bending even when the wall panel is subjected to a horizontal force perpendicular to the wall surface. This wall structure also includes rod-shaped reinforcing members called restraining members, which are installed diagonally like flint beams at the four corners of the rectangular wall frame formed by the supports, upper girders, and lower girders. The restraining members prevent distortion or twisting of the wall frame even when the wall panel surrounded by the wall frame is subjected to a horizontal force perpendicular to the wall surface, so the wall panel is also less likely to undergo out-of-plane deformation. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2022-109515 Summary of the Invention [Problem to be solved by the invention]

[0006] Wall panels are subjected to horizontal forces that are perpendicular to the wall surface (out-of-plane forces) or parallel to the wall surface (in-plane forces). When the horizontal force is a shear force parallel to the wall surface (hereinafter referred to as "in-plane shear force"), stress tends to concentrate in the areas near the four vertices of the wall panel (hereinafter referred to as "corners"). In particular, when the edges of wall panels are bent, the stress concentration at the corners becomes even more severe due to the cutouts at the corners. Excessive stress concentration at the corners can lead to excessive out-of-plane plastic deformation, i.e., buckling. Buckling renders the wall panel unable to withstand the horizontal force, resulting in a rapid decline in the horizontal strength of the wall structure. Therefore, wall structures require measures to prevent buckling of wall panels due to in-plane shear forces. However, vertical ribs alone are not sufficient to withstand in-plane shear forces. The restraint material disclosed in Patent Document 1 prevents deformation of the frame body caused by in-plane shear force, but cannot completely prevent buckling of the wall panels.

[0007] The object of the present invention is to solve the above-mentioned problems, and in particular to provide a wall structure of a simple structure that can improve horizontal strength by preventing buckling of wall panels caused by in-plane shear forces. [Means for solving the problem]

[0008] In one aspect of the present invention, a wall structure for a simple structure includes two vertical members, an upper frame, a lower frame, a wall panel, and four reinforcements. The two vertical members stand horizontally spaced apart. The upper frame is placed between the upper ends of the two vertical members. The lower frame is placed between the lower ends of the two vertical members. The wall panel is fitted into a space enclosed by the vertical members, the upper frame, and the lower frame. Four reinforcements are installed at each of the four corners of the space. Each reinforcement is triangular, with one side extending along one of the two vertical members and the other side extending along either the upper frame or the lower frame. The distance between the surface of each corner of the wall panel and the plate surface of each reinforcement is set so that when the wall panel is subjected to a horizontal force parallel to the wall surface and the corner of the wall panel deforms in an out-of-plane direction, the surface of the corner comes into contact with the plate surface of one of the four reinforcements. [Effects of the Invention]

[0009] In the wall structure of the present invention, when the corner of the wall panel deforms out of the plane due to in-plane shear force, the surface of the corner comes into contact with the plate surface of one of the reinforcement members, limiting the out-of-plane deformation of the corner. This prevents the wall panel from buckling due to in-plane shear force, thereby improving the horizontal strength of the wall structure.

[0010] Each reinforcement may include a hook. The hook is provided along one side or the other side of the reinforcement and is configured to hook onto one of two vertical members, the upper frame, or the lower frame. When assembling the wall structure, the hook of the reinforcement is hooked onto the vertical member, the upper frame, or the lower frame, so that the reinforcement can be easily fixed to the vertical member, etc. This improves the workability of the wall structure. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a photograph of a wall structure according to an embodiment of the present invention. [Figure 2] 2(a) is a front view of the frame shown in Fig. 1, and (b) is a perspective view of the wall panel shown in Fig. 1. [Figure 3]2(a) is a cross-sectional view of the stud and wall panel shown in FIG. 1, and FIG. 2(b) is a perspective view of the vicinity of the cross section shown in FIG. [Figure 4] This is a photograph of the area around the reinforcement material in the wall structure shown in Figure 1. [Figure 5] 2(a), (b), and (c) are three-view drawings of the reinforcing material shown in FIG. 1, and (d) is a cross-sectional view showing how the horizontal edge of the reinforcing material is hooked onto the upper frame. [Figure 6] (a) is a photograph showing a specimen of a wall structure undergoing an in-plane shear test, and (b) is a photograph showing a wall structure with buckling occurring in the wall panel. [Figure 7] 1 is a graph showing a load-deformation curve obtained as a result of an in-plane shear test. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. [Components of wall structure]

[0013] FIG. 1 is a photograph of a wall structure according to an embodiment of the present invention. The photograph particularly shows the wall structure laid horizontally for the purpose of undergoing an in-plane shear test (see below). When assembled into a simplified structure, the wall structure is erected with the side labeled "top" in the photograph facing up and the side labeled "bottom" facing down. As shown in the photograph, the wall structure includes a frame, wall panels 200, and reinforcement 300. The frame is comprised of columns 110, studs 120, a top frame 130, and a bottom frame 140. -Frame-

[0014] FIG. 2(a) is a front view of the frames 110-140. The pillars 110, studs 120, upper frame 130, and lower frame 140 are rectangular cylindrical members formed by pressing or other methods from painted hot-dip galvanized steel sheets several millimeters thick. Their cross sections (i.e., cross sections perpendicular to the lengthwise direction) measure several tens of millimeters by several tens of millimeters. The pillars 110 are vertical members located at both ends of the wall structure and support structures located above the wall structure, such as the roof of a simple structure. The studs 120 are vertical members located midway between the wall structure in the left-right direction and are sandwiched between two wall panels to support them. The pillars 110 and studs 120 are approximately 1,900 mm to 2,400 mm in height. In FIG. 1(b), two pillars 110 are erected horizontally spaced apart, and three studs 120 are erected between them at equal horizontal intervals. The upper frame 130 is placed horizontally between the upper ends of the columns 110 and studs 120, and the lower frame 140 is placed horizontally between the lower ends of the columns 110 and studs 120. The lengths of the upper frame 130 and lower frame 140 are 700 mm to 3,700 mm. The frames 110 to 140 surround four rectangular spaces 150 of the same size (several hundred mm wide, several thousand mm high), and one wall panel is fitted into each space 150. -Wall Panel-

[0015] 2(b) is a perspective view of the wall panel 200. The wall panel 200 is a rectangular plate material with a width of several hundred mm and a height of 1800 mm to 2200 mm, formed by pressing or the like from a painted hot-dip galvanized steel sheet several mm thick. Four ribs 201, 202, 203, and 204 are provided on the wall surface of the wall panel 200. The ribs 201 to 204 are ridge-like raised portions (protruding from the front to the back in the figure), which are arranged at intervals in the width direction and extend in the height direction over the entire height of the wall panel 200. By bending the four sides of the wall panel 200 in the same direction (toward the front in the figure), rectangular cylindrical vertical fixing portions 211 and 212 are formed on the left and right long sides, and elongated plate-like horizontal fixing portions 213 and 214 are formed on the top and bottom short sides. Accordingly, notches 218 are provided at the four vertices of the wall panel 200, i.e., at the intersections of the vertical fixing parts 211, 212 and the horizontal fixing parts 213, 214. Furthermore, a reinforcing band 220 made of a painted hot-dip galvanized steel sheet extends in the width direction across the entire width of the wall panel 200 at the middle part in the height direction of the wall panel 200. The ribs 201-204, fixing parts 211-214, and reinforcing band 220 make the wall panel 200 less likely to bend even when subjected to a horizontal force perpendicular to the wall surface.

[0016] 3A is a cross-sectional view of the stud 120 and the vertical fixing portions 211, 212 of the wall panel 200, and FIG. 3B is a perspective view of the vicinity of the cross-section shown in FIG. 3A. The stud 120 is rectangular tubular and has a U-shaped cross-section. The vertical fixing portions 211, 212 of the wall panel 200 are also rectangular tubular and have a J-shaped cross-section. The vertical fixing portions 211, 212 are fitted into the stud 120 so that the J-shaped tips 215, 216 of the vertical fixing portions 211, 212 are positioned inside the U-shape of the stud 120. A through-hole 121 is formed in the stud 120, and a through-hole 217 is formed in the vertical fixing portions 211, 212. The through-hole 121 in the stud 120 has been burred, and a female thread is cut into the raised cylindrical edge. Therefore, the vertical fixing parts 211, 212 are fastened to the stud 120 by threading the bolt 500 through the through-hole 217 of the vertical fixing parts 211, 212 into the female thread of the through-hole 121 of the stud 120. Such fastening parts are provided at three locations, at the top end, middle part, and bottom end of each vertical fixing part 211, 212. The column 110 and the vertical fixing parts 211, 212 of the wall panel 200 are similarly combined and fastened to each other. -Reinforcement material-

[0017] As shown in Fig. 2(a), the frames 110 to 140 surround four rectangular spaces 150. Intersections 151 of the frames 110 to 140 are located at the four corners of each space 150. As shown in Fig. 1, one reinforcing member 300 is installed in each of the areas of the space 150 close to each intersection 151, i.e., at each of the corners.

[0018] Figure 4 is a photograph of the area around reinforcement member 300 in the upper left corner of the wall structure shown in Figure 1. Reinforcement member 300 is in the shape of a right triangle, with vertex 301, whose interior angle is 90 degrees, placed at intersection 151 between column 110 and upper frame 130. One of the two sides intersecting at vertex 301 (hereinafter referred to as the "vertical side") 302 extends along column 110, and the other (hereinafter referred to as the "horizontal side") 303 extends along upper frame 130. In this way, reinforcement member 300 covers the corner of space 150 partitioned by column 110 and upper frame 130.

[0019] Figure 5(a) is a front view, (b) is a top view, and (c) is a side view of the reinforcement material 300 for the upper left corner shown in Figure 4. In practice, the reinforcement material for the upper right corner can be obtained by simply inverting Figure 5 horizontally, the reinforcement material for the lower left corner can be obtained by simply inverting Figure 5 vertically, and the reinforcement material for the lower right corner can be obtained by inverting both the left and right sides and the top and bottom of Figure 5.

[0020] The reinforcing member 300 is formed, for example, by punching a 1.6 mm thick, hot-dip galvanized steel sheet, and is a plate material in the shape of a right-angled isosceles triangle with a width and height of 200 mm to 300 mm. The vertical side 310 and horizontal side 320 of the reinforcing member 300 are bent in the same direction (toward the viewer in FIG. 5(a)), forming a long, thin, plate-shaped vertical fixing portion on the vertical side 310 and a long, thin, plate-shaped horizontal fixing portion on the horizontal side 320. Each fixing portion 310, 320 has three bolt holes 330 for fastening to the frame body. This allows the vertical fixing portion 310 to be fastened to the column 110 or stud 120, and the horizontal fixing portion 320 to be fastened to the upper frame 130 or lower frame 140.

[0021] The reinforcement material 300 for the upper left corner also has a hook 321 formed at the tip of the horizontal side 320. The same is true for the reinforcement material for the upper right corner. The hook 321 extends in the width direction across the entire width of the horizontal side 320 and has a J-shaped cross section (see Figure 5(c)).

[0022] 5(d) is a cross-sectional view showing how the horizontal fixing portion 320 of the reinforcing member 300 for the upper left corner is hooked onto the upper frame 130. The upper frame 130 is a square tube with a U-shaped cross section. The horizontal fixing portion 320 of the reinforcing member 300 has a hook 321 at the tip, which has a J-shaped cross section. In the process of fastening the reinforcing member 300 to the upper frame 130, first, the hook 321 of the horizontal fixing portion 320 is hooked onto the inside of the U-shape of the upper frame 130. Next, when the reinforcing member 300 is rotated around the hook 321, the upper surface 322 of the horizontal fixing portion 320 approaches the lower surface 131 of the upper frame 130, and they face each other in parallel with a predetermined gap GP between them. Although not shown in FIG. 5(b), when the left end portion 219 of the horizontal fixing portion 213 at the upper end of the wall panel 200 is inserted into this gap GP, the upper left corner of the wall panel 200 is fastened to the upper frame 130.231 The horizontal fixing portion 320 of the reinforcement 300 approaches the plate surface of the reinforcement 300 to within a predetermined distance (see FIG. 2(b)). Then, a bolt (not shown) is passed through the through hole 330 of the horizontal fixing portion 320 of the reinforcement 300 and the through hole 131 of the upper frame 130, and is screwed into the female thread 133 of the stopper 132 placed on the edge of the through hole 131 of the upper frame 130. In this way, the horizontal fixing portion 320 of the reinforcement 300 is fastened to the upper frame 130 with the horizontal fixing portion 213 of the wall panel 200 sandwiched between them. As a result, the plate surface of the reinforcement 300 is fastened to the upper left corner of the wall panel 200, i.e., the portion covering the upper left corner of the space 150 surrounded by the frames 110-140, to within a predetermined distance. The fastening between the reinforcement for the upper right corner and the upper frame 130 is similar. The fastening between the reinforcing members for the lower left and right corners and the lower frame 140 is similar except that there is no step of hooking. Wall panel buckling due to in-plane shear forces

[0023] The reinforcing material has two main roles. First, it prevents distortion and twisting of the frame bodies 110 to 140 caused by external forces. Second, it prevents buckling of the wall panel 200 caused by in-plane shear forces. The second role will be mainly described in detail below.

[0024] Figure 6(a) is a photograph showing a wall structure specimen undergoing an in-plane shear test. Unlike the wall structure shown in Figure 1, this specimen does not have any reinforcement installed. The in-plane shear test is intended to measure the specimen's resistance to in-plane shear force. The lower frame of the specimen (the front side in the photograph) is fixed to an external frame, while one end of the upper frame (the right end at the back side in the photograph) is connected to a hydraulic cylinder. In this state, the upper frame is subjected to a horizontal force from the hydraulic cylinder parallel to the wall surface of the wall panel (a force pointing to the right or left as indicated by the arrow in the photograph). This generates an in-plane shear force throughout the wall panel. In other words, the horizontal stress in the wall panel is stronger in the same direction as the horizontal force the closer it is to the horizontal fixing part at the top end (the back side in the photograph), and stronger in the opposite direction to the horizontal force the closer it is to the horizontal fixing part at the bottom end (the front side in the photograph).

[0025] Figure 6(b) is a photograph showing a wall structure in which buckling has occurred in the rightmost wall panel. As the horizontal force increases, the in-plane shear force also increases, causing stress to concentrate at the corners of each wall panel. When the horizontal force eventually reaches a certain level (the so-called ultimate strength), as shown in Figure 6(b), buckling occurs in the upper right corner of the rightmost wall panel, causing the entire wall structure to bend significantly along the diagonal. In particular, if the deflection is excessive, the bolts securing the rightmost wall panel to the right-hand column will come loose, as shown in the enlarged part of Figure 6(b). In this state, the wall panel can no longer withstand the horizontal force, and the horizontal strength of the entire wall structure will drop sharply.

[0026] As shown in Figure 6(b), the deflection of each wall panel is large at each corner of the wall panel. As can be easily inferred from this, buckling of the wall panel due to in-plane shear force occurs at the corners of the wall panel. Therefore, as shown in Figures 1 and 4, if the reinforcement members 300 cover the corners of the wall panel 200, when the corners of the wall panel 200 deflect due to in-plane shear force, i.e., when they deform in the out-of-plane direction, the surfaces of the corners come into contact with the plate surfaces of the reinforcement members 300. The distance between each corner of the wall panel 200 and the plate surfaces of the reinforcement members 300 is set accordingly. This contact limits out-of-plane deformation, such as deflection of the corners of the wall panel 200, making the wall panel 200 less likely to buckle. [Effectiveness of the invention as shown by the results of in-plane shear tests]

[0027] In-plane shear tests, as described below, have confirmed that the reinforcement actually improves the horizontal capacity of the wall structure by limiting the out-of-plane deformation of the wall panel corners.

[0028] In an in-plane shear test, the horizontal force applied to the test specimen is gradually increased. When the shear deformation of the wall panel reaches a predetermined magnitude, the direction of the horizontal force is reversed by 180 degrees. Since shear deformation is usually small, it is expressed as the rotation angle of the upper frame relative to the lower frame (hereinafter referred to as the "shear deformation angle" or "deformation angle"). First, when the deformation angle reaches 1 / 450 (= 0.0022) rad, the horizontal force is reversed. Next, in the opposite direction, the horizontal force is reversed when the deformation angle reaches 1 / 450 rad. This operation is repeated three times. Next, the deformation angle at which the horizontal force should be reversed is changed to 1 / 300 (= 0.0033) rad, and the same operation is repeated. The deformation angle at which the horizontal force should be reversed is then changed in the following order: 1 / 200 (=0.0050) rad, 1 / 150 (=0.0067) rad, 1 / 100 (=0.010) rad, 1 / 75 (=0.013) rad, 1 / 50 (=0.020) rad, and 1 / 30 (=0.033) rad. During this time, the strength of the horizontal force (load) and the shear deformation angle of the wall structure receiving the horizontal force are recorded.

[0029] Figure 7 is a graph showing the load-deformation curve obtained as a result of an in-plane shear test. The load-deformation curve is the envelope of a group of curves that represent the change in the horizontal force (load) applied to the test specimen and the shear deformation angle of the specimen during the test. Figure 7 shows the portion of the load-deformation curve where the horizontal force is in the same direction, particularly the portion where the horizontal force is positive. In Figure 7, the thin curve CV1 represents the test results for the specimen without reinforcement (hereinafter referred to as the "standard specification") shown in Figure 6(a), and the thick curve CV2 represents the test results for the specimen with reinforcement (hereinafter referred to as the "reinforced specification") shown in Figure 1. The curves CV1 and CV2 are the same in Figures 7(a) and 7(b), and only the values ​​represented on the vertical axis differ. The vertical axis of Figure 7(a) represents the strength of the horizontal force as a relative value (%) based on the strength when the standard specification reaches a specific deformation angle of 1 / 450 rad, and the vertical axis of Figure 7(b) represents the strength of the horizontal force as a relative value (%) based on the maximum strength that the standard specification can withstand.

[0030] As shown in Figure 7(a), the horizontal force required to reach a certain deformation angle is stronger for the reinforced specification than for the standard specification. Specifically, the horizontal force required to reach a deformation angle of 1 / 450 rad for the reinforced specification is approximately 64% stronger than for the standard specification. This means that the reinforcement material is successful in suppressing the initial deformation of the wall structure.

[0031] Furthermore, as shown in Figure 7(b), the horizontal force that the wall structure was ultimately able to withstand was stronger with the reinforced specification than with the standard specification. Specifically, the maximum horizontal force that the reinforced specification was able to withstand was approximately 48% stronger than with the standard specification. This means that the reinforcement material also succeeded in improving the ultimate strength of the wall structure. [Variations]

[0032] (1) The shapes, sizes, materials, etc. of the components of the wall structure shown in the above-described embodiments of the present invention are merely examples and can be modified in various ways. For example, the materials of the frame, wall panels, or reinforcing members may be steels other than painted hot-dip galvanized steel, or other metals such as aluminum. The dimensions of the columns, partitions, upper frames, lower frames, or wall panels may be different. The number of partitions may be two or fewer, or four or more, and the number of wall panels may be three or fewer, or five or more. There may be no partitions and only one wall panel. The triangular shape formed by the reinforcing members is not limited to a right-angled isosceles triangle, but may also be a scalene right triangle. Furthermore, as long as buckling of the corners of the wall panels due to in-plane shear forces is suppressed, the reinforcing members do not need to completely cover the entire corners. For example, the vertices of the reinforcing members may be away from the intersections of the frame members, or holes may be drilled in the plate surfaces of the reinforcing members.

[0033] (2)In the above-described embodiment of the present invention, the reinforcement member 300 for the upper left or upper right corner includes a hook 321. In this case, when assembling the wall structure, the reinforcement member 300 for the upper left or upper right corner can be easily combined with the upper frame 130 by hooking the hook 321 onto the upper frame 130, simplifying the fastening process. This improves the workability of the wall structure. However, the hook 321 is not an essential component of the present invention and may be omitted. Alternatively, the hook may be provided on the horizontal edge of the reinforcement member for the lower left or lower right corner so that the reinforcement member can be hooked onto the lower frame 140, or on the vertical edge of the reinforcement member so that the reinforcement member can be hooked onto the column 110 or stud 120. [Explanation of symbols]

[0034] 110 pillars 120 Studs 130 Upper Frame 140 Bottom frame 200 wall panels 300 Reinforcement

Claims

1. Two vertical members spaced horizontally apart, an upper frame spanning the upper ends of the two vertical members; A lower frame extending between the lower ends of the two vertical members; a wall panel fitted into a space surrounded by the two vertical members, the upper frame, and the lower frame; Four reinforcements installed at each corner of the space; A wall structure of a simple structure comprising: Each stiffener is a triangular plate, One side of each stiffener extends along one of the two vertical members; The other side of each reinforcing member extends along either the upper frame or the lower frame, The distance between each corner of the wall panel and the plate surface of each reinforcing member is set so that when the wall panel is subjected to a horizontal force parallel to the wall surface and the corner of the wall panel is deformed in an out-of-plane direction, the surface of the corner comes into contact with the plate surface of one of the four reinforcing members. A wall structure characterized by:

2. Each reinforcement is a hook provided along the one side or the other side and configured to hook onto one of the two vertical members, the upper frame, or the lower frame; The wall structure of claim 1 , comprising:

Images