WO2011077604A1 - Wall panel - Google Patents

Abstract

Disclosed is wall panel provided with a pair of frame members (2) which are disposed at an interval in such a way as to face each other; a face plate (3) which is a thin bent steel plate, is fixed to these frame members (2), and is configured in such a way that crests (6) and troughs (7) are alternately formed from one end to the other end; and screws (8) which fix the troughs (7) of this face plate (3) to the frame members (2). The aforementioned wall panel (1) serves as a load-bearing wall and is such that when structural in-plane shear force acts on the frame members (2), those portions of the face plate (3) which are around the screws (8) undergo bearing deformation, thereby making resistance. The ratio of the coming-off strength of the screws (8) to the bearing strength of the face plate (3) is set to a predetermined value at which the shanks (8B) of the screws (8) incline when the face plate (3) undergoes bearing deformation.

Description

Wall panels

The present invention relates to a wall panel used in a building such as a thin plate lightweight steel structure.
This application claims priority based on Japanese Patent Application No. 2009-291205 filed in Japan on December 22, 2009, the contents of which are incorporated herein by reference.

Conventionally, a wall panel in which a folded plate as a face material is joined to one side or both sides of a frame material has been used as a wall panel in a load-bearing wall for thin plate lightweight steel construction (see, for example, Patent Documents 1 to 3).

In the load-bearing walls described in Patent Documents 1 and 2, the folded plate and the frame member are rigidly joined such that the folded plate is welded to the frame member or fixed to the frame member through a reinforcing member. The frame material itself also forms a rigid frame and is fixed to a building frame such as a beam. Such a load-bearing wall is configured such that when a horizontal force such as an earthquake acts on a building, the folded plate bears a shearing force to ensure the horizontal strength of the building. Therefore, the retained horizontal strength of the building is determined based on the shear strength of the folded plate.

Patent Document 3 proposes that a folded plate is screwed to a vertical frame and the folded plate is also used as a reinforcing material for the vertical frame. Furthermore, in Patent Document 3, a folded plate is effective as a steel plate face material for preventing deformation of a frame material made of a thin lightweight steel, and further, by arranging joints in an orthogonal direction with respect to the frame material, It is described that the bearing wall is excellent in yield strength and deformation performance.

In order to further improve the deformation performance of the folded plate bearing wall by the applicant, Patent Document 4 avoids the overall buckling and local buckling of the face material so as to cause the bearing material to deform under pressure at the screw joint. It has a folded plate shape. In addition, it has been proposed to combine a screw plate, a frame member, and a screw that avoid screw break-out, frame bearing failure, screw breakage, and the like that occur at the screw joint. Furthermore, in Patent Document 4, the screw head is enlarged so that the screw does not come out of the long hole formed by the bearing deformation of the screw hole, and so that local deformation (flaw) around the screw hole does not occur. It has been proposed that the screw shaft diameter should not be too large.

Japanese Utility Model Publication No. 2-49449 Japanese Patent Laid-Open No. 9-228520 JP 2007-303269 A JP 2009-209582 A

In the conventional load-bearing wall, since the building is designed based on the shear strength of the folded plate, the joint portion between the folded plate and the frame member and the joint portion between the load-bearing wall and the building frame are rigidly joined. That is, these bonding strengths are set to be equal to or greater than the shear strength of the folded plate. For this reason, there exists a problem that a joining structure becomes large-scale and the effort and cost of manufacture and field construction will increase.
Moreover, in the wall panel described in Patent Document 4, the mechanical properties (yield ratio or elongation at break) of the folded plate are not clearly suggested. As a result, there is a problem that the bearing deformation of the screw joint portion in the folded plate cannot be stably ensured, and there is a possibility that the proof stress reduction after the maximum proof stress is large may occur.

The present invention aims to solve the above-mentioned problems and to provide a wall panel that can stably secure a supporting pressure deformation of a screw joint portion in a folded plate and has excellent deformation performance.

The present invention employs the following means in order to solve the above problems and achieve the object.
That is,
(1) The wall panel of the present invention has a pair of frame members arranged opposite to each other with a space between them; fixed to these frame members, and crests and troughs are alternately formed from one to the other. A surface material that is a folded plate of a thin steel plate; and a screw that fixes a valley portion of the surface material to each frame material; and when the in-plane shear force acts on each frame material, A wall panel for a load bearing wall in which the surrounding portion of the screw is resisted by bearing deformation, and the ratio of the screw withdrawal resistance to the bearing load resistance of the face material is the The shaft portion is set to a predetermined value that is inclined.

(2) In the wall panel of the present invention described in (1) above, the predetermined value may be 0.7 or more.

(3) In the wall panel of the present invention described in (1) or (2) above, the predetermined value may be 1.6 or less.

(4) The wall panel of the present invention described in (1) or (2) further includes a washer into which a screw is inserted, and a ratio obtained by dividing the outer diameter of the washer by the shaft diameter of the shaft portion of the screw. However, it may be 3.0 or more.
(5) In the wall panel of the present invention described in (4) above, the predetermined value may be 4.0 or less.

(6) In the wall panel of the present invention described in (4) above, the frame member is arranged in a direction orthogonal to the first frame member arranged in the extending direction of the valley part and the extending direction of the valley part. A square frame is formed by the first frame member and the second frame member, and a washer is inserted only in a screw that fixes the first frame member to the valley portion of the face member. May be.
(7) In the wall panel of the present invention described in (4) above, a gap may be formed between the hole of the washer and the shaft portion of the screw.
(8) In the wall panel of the present invention described in (4) above, the ratio obtained by dividing the difference obtained by subtracting the shaft diameter of the screw shaft from the inner diameter of the washer by the thickness of the washer is 0.1 to It may be 0.6.

(9) In the wall panel of the present invention described in (1) above, the breaking elongation of the face material may be 1% or more and less than 16%.

(10) In the wall panel of the present invention described in (1) above, the pitch of the screw threads may be equal to or less than the thickness of each frame member.

(11) In the wall panel of the present invention described in (1) above, the yield ratio of the face material may be 77% to 96%.

(12) In the wall panel of the present invention described in (1) above, at least one side of the face material along the extending direction of the valley portion is centered on the screw hole through which the shaft portion of the screw is inserted. Ribs that are orthogonal to the extending direction may be further provided.

(13) In the wall panel of the present invention described in (1) above, on both sides along the direction orthogonal to the extending direction of the valley portion, centering on the screw hole through which the shaft portion of the screw is inserted. In addition, a thin portion having a thin plate thickness may be formed partially.

(14) In the wall panel of the present invention described in (1) above, on both sides along the direction orthogonal to the extending direction of the valley portion, centering on the screw hole through which the shaft portion of the screw is inserted. In addition, a low-strength portion whose mechanical strength is partially lower than the surroundings may be formed.

When the in-plane shear force is applied to the bearing wall, the surrounding part of the face material is deformed under pressure. At this time, according to the wall panel of the present invention described in the above (1), since the ratio of the screw proof stress to the bearing proof strength of the face material is set to a predetermined value, the rapid proof strength due to screw detachment is set. The decrease can be suppressed. Thereby, the screw periphery of a face material can be stably plastically deformed, and the energy generated in the composition surface can be absorbed. Further, it is possible to prevent a sudden decrease in the proof stress of the load bearing wall as compared with the conventional load bearing wall after improving the deformation performance of the face material. As a result, the wall panel is excellent in deformation performance. Further, by utilizing the inclination of the shaft portion of the screw, the plasticized face material gathered in the vicinity of the screw gathers at the tip portion of the screw hole and is easily crushed and eliminated.

According to the wall panel of the present invention described in the above (2), since the ratio of the unscrewing strength of the screw to the bearing strength of the face material is 0.7 or more, the tip of the screw is a frame material before the screw is inclined. Can be prevented from coming off.

According to the wall panel of the present invention described in (3) above, since the ratio of the screw pull-out proof strength to the bearing proof strength of the face material is 1.6 or less, the screw (particularly, the head of the screw) is the face material. The screw can be tilted without going underneath.

According to the wall panel of the present invention described in (4) above, the screw (especially the head of the screw) is placed under the face material by arranging the washer so as to overlap the range in which the stress around the screw is largely applied. The screw can be tilted without being submerged. Furthermore, by using a washer and screw with a ratio obtained by dividing the outer diameter of the washer by the shaft diameter of the shaft portion of the screw of 3.0 or more, the screw head does not sink under the face material. Even if the deformation progresses, the face material can exhibit a stable bearing strength.
According to the wall panel of the present invention described in (5) above, by using a washer, the upper limit of the ratio of the unscrewing strength of the screw to the bearing strength of the face material can be relaxed. That is, when the predetermined value is 4.0 or less, the screw can maintain the yield strength, and the screw can be inclined without being submerged under the face material.
Further, when a square frame is formed by the first frame member and the second frame member, the square frame is fixed to the first frame member as compared with the bearing deformation of the face member fixed to the second frame member. The bearing deformation of the face material is greater. Therefore, according to the wall panel of the present invention described in the above (6), since the washer is inserted only into the screw that fixes the face material to the first frame member, the screw (particularly, the head of the screw). ) Can be suppressed from entering under the face material, and the assembly process and the number of parts can be reduced. That is, the overall production cost can be suppressed while stably securing the supporting pressure deformation around the screw in the face material.

According to the wall panel of the present invention described in (7) above, since the gap is formed between the hole of the washer and the shaft portion of the screw, the screw is inclined using this gap. Thereby, when the periphery of the screw of the face material is subjected to bearing deformation, the inclination range of the screw is limited, so that it is possible to suppress a sudden decrease in yield strength due to unscrewing of the screw.
According to the wall panel of the present invention described in (8) above, the screw is inclined at an appropriate inclination angle by defining the inner diameter dimension of the washer, the axial diameter dimension of the shaft portion of the screw, and the thickness dimension of the washer. be able to.

In addition, in the case of a face material with a large elongation at break, the plastic material near the screw hole clings to the screw shaft, increasing the load on the screw shaft and increasing the yield strength of the bearing wall. Alternatively, there is a risk that the screw may come out of the screw hole. However, when a face material having a small elongation at break (brittle) is combined with a wall panel, the plasticized face material near the screw hole is easily removed as chips. Thereby, since the burden of a screw shaft part does not increase extremely, the proof stress of a load bearing wall is stabilized and the outstanding deformation | transformation performance can be exhibited.
Therefore, according to the wall panel of the present invention described in (9) above, the breaking elongation of the face material is 1% or more and less than 16%. Thus, by using a face material having a small breaking elongation, the plasticized portion of the face material around the screw supported by the screw is easily crushed and eliminated. Thereby, since the plasticized face material gathered around the screw does not resist the screw, the face material can be stably plastically deformed. Furthermore, stable proof stress and deformation performance can be exhibited.

According to the wall panel of the present invention described in (10) above, even when the screw is inclined, the screw thread is hooked to the frame member 360 degrees all around, so that the screw can be more reliably prevented from coming out of the frame member. , Can exhibit a stable proof stress.

According to the wall panel of the present invention described in (11) above, high YR steel having a yield ratio of 77% to 96% is used as the face material, not low YR (yield ratio) steel. As a result, the plasticizing region in the case where the periphery of the screw hole of the face material is plastically deformed by the bearing pressure of the screw shaft portion can be narrowed. Therefore, since the hole width of the screw hole into which the screw is inserted is not extremely widened, the screw (particularly, the head of the screw) can be prevented from entering the face material, and the load bearing wall is greatly deformed by shear deformation. Even so, the proof stress of the load bearing wall can be stabilized.

According to the wall panel of the present invention described in (12) above, the rib can prevent local buckling in the direction orthogonal to the direction in which the folded plate is plasticized, and the predetermined direction of the bearing wall The face material can be plasticized.

According to the wall panel of the present invention described in (13) above, when the screw periphery of the folded plate is plasticized with screws, the thin plate portion is plasticized. Thus, wrinkles can be prevented from occurring in the face material by limiting the plasticizing range to a specific place. A wrinkle indicates, for example, local out-of-plane buckling.

According to the wall panel of the present invention described in the above (14), when the screw periphery of the folded plate is plasticized with a screw, the strength-decreasing portion is plasticized. Thus, by limiting the plasticizing range to a specific place, the proof stress of the load bearing wall can be stabilized even when the face material is greatly deformed.

It is a front view which shows the wall panel applied to the load-bearing wall of 1st Embodiment of this invention. It is a side view of the same wall panel of FIG. It is the sectional view on the AA line of the same wall panel of FIG. It is a schematic perspective view of the same wall panel shown in FIG. It is a partial expansion perspective view of the edge part of the same wall panel shown in FIG. It is explanatory drawing which shows the destruction mode in the screw junction part of the same wall panel. It is explanatory drawing which shows the destruction mode in the screw junction part of the same wall panel. It is explanatory drawing which shows the destruction mode in the screw junction part of the same wall panel. It is explanatory drawing which shows the destruction mode in the screw junction part of the same wall panel. It is explanatory drawing of the element test of the screw junction part of a folded plate. It is a front view of the folded plate used by the same element test. It is a side view of the same folding plate used in the same element test. It is a side view of the frame material piece used by the same element test. It is sectional drawing which shows the partial dimension shape of the same folding plate. FIG. 7B is a diagram comparing envelopes of a load-displacement relationship obtained by an element test of the screw joint portion of the folded plate shown in FIG. 7A. FIG. 7B is a diagram comparing envelopes of a load-displacement relationship obtained by an element test of the screw joint portion of the folded plate shown in FIG. 7A. It is sectional drawing which shows the state in which the screw sunk into the face material. It is a fragmentary sectional view in case a screw inclines with respect to a folded plate with big fracture | rupture elongation. It is a perspective view of the plasticizing part of the folded plate in FIG. 10B. It is a fragmentary sectional view in case a screw inclines with respect to a folded plate with small breaking elongation. It is a perspective view of the plasticizing part of the folded plate in FIG. 10D. It is sectional drawing of the screw joint part which has joined the frame material and the face material in the state in which the screw inclined. FIG. 11B is a cross-sectional view showing the relationship between the screw diameter and the thickness dimension of the outermost edge of the face material in the BB cross section of FIG. 11A. Fig. II of “Steel Structure Joint Data Collection” edited by Japan Steel Structure Association. It is explanatory drawing which shows stress distribution around a bolt hole published in 5.12. Fig. II of “Steel Structure Joint Data Collection” edited by Japan Steel Structure Association. It is a graph which shows the stress distribution by the distance from a bolt center published in 5.12. It is sectional drawing explaining the relationship between the clearance between a washer internal diameter and a screw shaft part, and the inclination of a screw and a washer in case a clearance is small. It is sectional drawing explaining the relationship between the clearance between a washer internal diameter and a screw shaft part, and the inclination of a screw and a washer in case a clearance is large. It is explanatory drawing which shows the element test of the folded plate from which the position of a screw junction part differs. It is a front view of the folded plate used by the same element test. It is a side view of the folded plate used in the same element test. It is a side view of the frame material piece used by the same element test. It is sectional drawing which shows the partial dimension shape of a folded plate. FIG. 16 is a graph comparing envelopes of load-displacement relationships obtained in the element test shown in FIGS. 15A to 15D. FIG. FIG. 16 is a graph comparing the load-displacement envelopes obtained in the same element test shown in FIGS. 15A to 15D. FIG. It is a front view which shows the dimension shape of the test body used by the proof stress test of a wall panel. It is a graph which shows the load-deformation angle relationship obtained by the proof stress test using the test body shown in FIG. It is sectional drawing for demonstrating the relationship between the screw thread pitch of a screw, and the detachment | leave of a screw when a screw inclines. It is sectional drawing which shows the case where the front-end | tip sharp screw is attached to a frame material. It is a front view which shows the condition which sets a wall panel to a loading test apparatus and is performing the loading test. It is the graph which compared the envelope of the load-deformation angle relationship obtained by the same loading test. It is a front view which shows the state which the supporting pressure is acting on the face material of low YR from a screw shaft part, Comprising: One part is seen in cross section. FIG. 24B is a front view showing a state where the face material is plastically deformed in a state where the frame material and the face material are deviated from the state of FIG. It is a figure corresponding to Drawing 24A, and is a front view showing the state where support pressure is acting on a face material of high YR, and a part is sectioned. It is a front view which shows the state which the face material has deformed plastically in the state which the frame material and the face material shifted | deviated from the state of FIG. 24C, Comprising: One part is seen in cross section. It is sectional drawing of the screw junction part which joins the frame material and a face material in the state before a screw inclines. It is explanatory drawing shown about the relationship between the yield ratio YR of a face material, and the plasticization area | region of a face material. It is a partial front view which shows the wall panel of other embodiment of this invention. FIG. 26B is a partial cross-sectional view of the wall panel as viewed from the CC line in FIG. 26A. It is a partial side view at the time of seeing the same wall panel from the DD line of FIG. 26A. It is a partial front view which shows the wall panel of further another embodiment of this invention. It is the side view of the partial figure 27A at the time of seeing the same wall panel from the EE line of Figure 27A. It is a figure corresponding to Drawing 27A, and is a partial front view of a wall panel in the state where a screw is not attached. It is a figure which expands and shows the thin-plate part in the folding plate of the same wall panel, Comprising: It is a fragmentary sectional view at the time of seeing from the FF line | wire of FIG. 27C.

Hereinafter, each embodiment of the present invention will be described with reference to the drawings. In the following description and the drawings used in this description, elements having substantially the same functional configuration are denoted by the same reference numerals, and redundant description thereof is omitted.

FIG. 1 is a front view showing a wall panel 1 according to an embodiment of the present invention. FIG. 2 is a side view of the wall panel 1. 3 is a cross-sectional view of the wall panel 1 taken along line AA of FIG. FIG. 4 is a perspective view of the wall panel 1. FIG. 5 is an enlarged perspective view showing a part of the wall panel 1.

The wall panel 1 is used as a load-bearing wall in a framed wall construction building. For example, after the wall panel 1 is installed on a foundation, the lower end portion of the wall panel 1 is connected to an anchor bolt, while the upper end portion of the wall panel 1 is connected to a building beam or a floor panel. Alternatively, the upper and lower ends of the wall panel 1 are connected to the upper and lower beams and the floor panel. As shown in FIG. 1, the wall panel 1 is composed of a combination of a frame member 2 and a folded plate 3. The folded plate 3 is a surface material made of a thin steel plate, and as shown in FIG. 2, is a surface material in which a plurality of peak portions 6 and a plurality of valley portions 7 are alternately formed from one side to the other.
The frame member 2 is made of a thin lightweight steel (grooved steel), and as shown in FIG. 1, a pair of vertical frame members (first frame members) arranged in the extending direction of the valley portion 7 of the folded plate 3. ) 2A and a pair of horizontal frame members (second frame members) 2B arranged along the direction orthogonal to the extending direction of the valley 7 of the folded plate 3 form, for example, a rectangular square frame Yes. Further, a frame member 2C is provided between the vertical frame members 2A. Further, the folded plate 3 is joined to one surface of a quadrilateral frame constituted by the frame member 2A and the frame member 2B.
As the frame wall construction method, for example, a relatively small building of about 2 to 4 floors is suitable. In addition to the wall panel 1, pillars, beams, floor panels, roofs, exterior materials, interiors It is composed of materials.

As shown in FIG. 3, the frame member 2 of the wall panel 1 includes a web 4 and a pair of flanges 5 that are continuous with both ends of the web 4, and has a substantially C-shaped cross section. And the vertical frame material 2A provided in a both-ends edge consists of two channel steels mutually joined by the webs 4 mutually.
The screw 8 is a tapping screw or the like, and the screw 8 penetrating the valley portion 7 of the folded plate 3 from the opposite side of the frame member 2 is screwed into the frame member 2, whereby the folded plate 3 is attached to the frame member 2. The trough 7 is fixed.

Shown in the enlarged portion of FIG. 2, the relationship between the thickness t ₁ of the shaft diameter d ₁ and folded plate 3 of an outer diameter D and the shaft 8B of the head 8A of the screw 8 of the wall panel 1, the following equation (1 ) Is set.
(Dd ₁ )> α ₁ · t ₁ (1)

Here, α ₁ is a coefficient representing a condition for preventing the head portion 8A of the screw 8 from coming out of the screw hole 9 generated in the folded plate 3 due to the support pressure of the shaft portion 8B. α ₁ is desirably 7.0 or more. According to such a configuration, even if the screw 8 is repeatedly subjected to a load and the periphery of the shaft portion 8B of the folded plate 3 is deformed by supporting pressure, the screw hole 9 of the screw 8 becomes large. The head 8 </ b> A is caught on the folded plate 3. Thereby, it can prevent that the screw 8 falls off from the folded plate 3, and can ensure a deformation | transformation performance.

The relationship between the shaft diameter d ₁ of the shaft portion 8B of the screw 8 of the wall panel 1 and the plate thickness t _{1 of the} folded plate 3 is set by the following equation (2).
d ₁ <α ₂ · t ₁ (2)

Here, α ₂ is a coefficient representing a condition for preventing the growth of the screw hole 9 from being hindered by local buckling generated in the folded plate 3 by the shaft portion 8B of the screw 8. α ₂ is desirably 13 or more. According to such a configuration, a long hole starting from the screw hole 9 is formed in the folded plate 3 by the support pressure of the shaft portion 8B of the screw 8, so that the support pressure caused by wrinkles around the shaft portion 8B is formed. Compared with deformation, higher deformation performance can be ensured.

To realize the above deformation (destructive mode), it is necessary to set conditions that do not cause other destructive modes. That is, in the peripheral portion of the screw 8 of the folded plate 2 (screw joint portion 8C), the screw 8 is pulled out as shown in FIG. 6A, or the wrinkles 13 are generated in the face material 3 as shown in FIG. 6B. As shown in FIG. 6C, it is necessary to set a condition that does not cause a fracture mode in which the frame member 2 is cut or the screw 8 is cut as shown in FIG. 6D. The wrinkle 13 refers to local out-of-plane buckling. Furthermore, it is necessary to set conditions for causing no overall buckling or local buckling even in the entire wall panel 1.

First, the above-described conditions of the screw joint portion 8C, which is a joint portion between the frame member 2 and the folded plate 3 and the screw 8 in the wall panel 1, are set. Here, for example, using the calculation formula for the allowable shear strength (Ras) of the threaded joint described in “Drill Screw Joint Design and Construction Guidelines” by the Japan Iron and Steel Federation, the following formula (3) is used. .
R _as = R _as3-1 <min (α ₃ · R _as2 , α ₄ · R _{as3 -2} , α ₅ · R _as4 ) (3)

In equation (3), R _as2 is the pull-out resistance (kN) of the screw 8 shown in FIG. 6A and is calculated by the following equation (4). R _as3-1 is the bearing strength (kN) around the screw of the folded plate 3 shown in FIG. 6B, and is calculated by the following equation (5). R _as3-2 is the bearing strength (kN) around the screw of the frame member 2 shown in FIG. 6C, and is calculated by the following equation (6). R _as4 is the axial shear strength (kN) of the screw 8 shown in FIG. 6D and is calculated by the following equation (7). In each of the formulas (4) to (7), t ₁ is the design plate thickness (mm) of the folded plate 3, t ₂ is the design plate thickness (mm) of the frame member 2, and F _u1 is , The tensile strength (N / mm ² ) of the folded plate 3, F _u2 is the tensile strength (N / mm ² ) of the frame member 2, and d ₁ is the shaft diameter of the shaft portion 8 B of the screw 8. (Mm), _Ad is the axial cross-sectional area (mm ² ) of the screw 8, and D is the head diameter (mm) of the screw 8.

The pull-out resistance R _as2 (kN) of the screw 8 can be obtained by the following equation (4).
R _as2 = Cs × Ce × d ₁ × t ₂ × F _u2 (4)
_{Cs = 1.3-0.3 × (d 1/} 5)
Ce = 0.28 × 3.95 × ξ ^0.5 × (t ₂ / d ₁ ) ^0.5
Here, ξ is an influence coefficient and is calculated by the following equation.
ξ = 3.1-5.6 (t ₁ / t ₂ ) +3.5 (t ₁ / t ₂ ) ²
Cs is a coefficient considering the screw diameter. Further, Ce is a coefficient that takes into consideration the screw diameter and the frame material plate thickness.

The bearing strength R _as3-1 (kN) around the screw of the folded plate can be obtained by the following equation (5).
R _as3-1 = Cs × Ce × d ₁ × t ₁ × F _u1 (5)
Ce = min (Ce ₁ , Ce ₂ )
Ce ₁ = 0.28 × {0.471 + 9.42 × t ₂ / d ₁ }
Ce ₂ = 0.959
Here, Ce ₁ is a coefficient considering the screw diameter and the folded plate thickness. Ce ₂ is a constant based on the experimental results.

The screw bearing strength R _as3-2 (kN) of the frame member 2 can be obtained by the following equation (6).
R _as3-2 = Cs × Ce × d ₁ × t ₂ × F _u2 (6)
Ce = min (Ce ₁ , Ce ₂ )
Ce ₁ = 0.28 × {1.18 + 5.26 × t ₁ / d ₁ }
Ce ₂ = 0.677
Here, Ce ₁ is a coefficient considering the screw diameter and the frame material plate thickness. Ce ₂ is a constant based on the experimental results.

The axial shear strength R _as4 (kN) of the screw 8 can be obtained by the following equation (7).
R _as4 = fs × A _{d ≈120} × A _d (7)
Here, fs is the reference strength (N / mm ² ) of the drill screw.

As described above, since the shear strength R _as of the joint portion between the frame member 2 and the folded plate 3 is set, the fracture mode at this joint portion is the bearing resistance strength R _as3-1 of the folded plate 3 around the screw. Determined by. As a result, when a shearing force is applied to the wall panel 1, although not shown in the figure, the folded plate 3 in a portion penetrated by the screw 8 is deformed by pressure, so that the screw 8 is pulled out (screwing out resistance R of the screw 8). _as2 ), deformation around the screw of the frame member 2 (bearing resistance strength _Rs3-2 around the screw of the frame member 2), fracture of the shaft of the screw 8 (shaft shear strength R _{as4 of the} screw 8), etc. do not occur. In addition, although the formula which became the basis of Formula (3) was a formula which determines proof stress in the fracture mode which appears first, in this embodiment, even if the screw circumference support mode of the folded plate 3 does not develop from the beginning. Good. Α ₃ to α ₅ do not need to be 1.0 because they may be expressed after other modes are expressed. α ₄ to α ₅ have no upper limit, and the lower limit is preferably 0.5 or more. α ₃ is preferably in the range of 0.7 to 4.0 because if it is too small, the screw is likely to come out, and if it is too large, the screw may not tilt.

Next, the above conditions for the wall panel 1 are set. The shear strength Q _{U in the} entire wall panel 1 is set so as to satisfy the following equation (8). Q _{b in the} formula (8) is a shear strength (kN) based on the allowable shear strength R _as of the joint portion shown in the following formula (9), and Q _y is the shear of the folded plate 3 shown in the formula (10). It is the yield strength (kN), Q _G is the shear yield strength (kN) based on the overall buckling strength τ ^e _{cr, G} of the folded plate 3 shown in the following formula (11), and Q _L is the following formula ( 12) The shear yield strength (kN) based on the local buckling strength τ ^e _{cr, L} of the valley 7 of the folded plate 3 shown in 12). In addition, about Formula (11) and Formula (12), the formula in the corrugated steel web synthetic | combination structure research group "corrugated steel sheet web PC bridge plan manual, December, 1998 issue" is used, for example.

Q _u = Q _b <min (α ₆ · Q _y , α ₇ · Q _G , α ₈ · Q _L ) (8)

Q _b = α ₉ · R _as · h / p (9)

In Equation (9), R _as is the long-term allowable shear strength of the screw joint, and the maximum strength is about three times that. However, since it is difficult for all the screws 8 to bear the load equally, α ₉ is set to 3.0 to 2.0. As shown in FIG. 4, h is the width (mm) of the wall panel 1, and p is the screw pitch (mm) of the screw 8.

Q _y = F ₁ / √3 · h · t ₁ (10)

In Expression (10), h is the width (mm) of the wall panel 1 shown in FIG. 4, t ₁ is the thickness (mm) of the folded plate 3 shown in FIG. 5, and F ₁ is the F of the folded plate 3. Value (N / mm ² ).

Q _G = τ ^e _{cr, G} · h · t ₁ = 36β {(EI _y ) ^1/4 × (EI _X ) ^3/4 } h / h _d ² (11)
^{_{I x = t 1 3 (δ}} 2 tens 1) / (6η) ... ( 11a)
I _y = t ₁ ³ / {12 (1-μ ² )} (11b)

In Expression (11), β is a coefficient indicating the degree of fixation of the end portion of the face material 3, and here, β = 1.0 in the case of a pin. E is the Young's modulus (E = 205 (kN / mm ² )) of the folded plate 3. I _x is a moment of inertia of the cross section per unit length with respect to the neutral axis in the direction orthogonal to the direction of the folding line of the folded plate 3, and is calculated by the equation (11a). In this formula (11a), t ₁ is the thickness (mm) of the folded plate 3, δ is the plate height ratio, and as shown in FIG. Δ = d / t ₁ where d is the height of. Further, η is the ratio (L / L1) of the actual dimension (projected length) L of the peak part to the length dimension L1 when the peak part in the direction orthogonal to the folding line direction shown in FIG. This is the rate of decrease in the length of the crests of the folded plate 3. h _d is the distance between the fulcrums in the width direction of the folded plate 3, and h _d = h / 2 when there is one middle rail. In the equation (11), I _y is a secondary moment of the cross section per unit length with respect to the neutral axis in the direction parallel to the folding line direction of the folded plate 3, and is calculated by the equation (11b). In this formula (11b), μ is the Poisson's ratio (μ = 0.3) of the folded plate 3.

Although not shown in the figure, the overall buckling strength of the folded plate 3 determined by such an equation (11) is a failure mode in which the entire folded plate 3 buckles across a plurality of peaks 6 and valleys 7. It is the strength when it occurs. And the big factor which determines the whole buckling strength is the height d of the peak part of the peak part 6, and the whole buckling strength can be ensured by setting the height d of this peak part to a predetermined value or more.

Q _L = τ ^e _{cr, L} · h · t ₁ = k (π ² E) / {12 (1 μ ² )} · γ ² · h · t ₁ (12)

In Expression (12), k is a shear buckling coefficient (k = 4.00 + 5.34 / α ² ). Here, α is the aspect ratio (α = a / h), and as shown in FIG. 4, a is the valley width (mm) of the folded plate 3, and h is the width (mm) of the wall panel. It is. Further, in the equation (12), [pi is pi, gamma is the width-thickness ratio of the folded plate _{3 (γ = t 1 / h} ). Although illustration is omitted, the local buckling strength of the valley portion 7 of the folded plate 3 determined by such an expression (12) is the strength when a fracture mode in which each valley portion 7 buckles occurs. . A major factor that determines the local buckling strength is the width-thickness ratio γ of the valley portion 7. That is, the local buckling strength can be ensured by setting the valley width a of the valley portion 7 to a predetermined value or less.

In Formula (8), since the failure mode of the screw joint portion may be manifested after other modes are manifested, α ₆ to α ₈ need not be 1.0, and 0.5 The above is desirable.

According to such a configuration, since the shear strength determined by the bearing strength around the screw of the folded plate 3 is set to be smaller than the shear yield strength of the folded plate 3, the folded plate 3 is more likely to yield shear. Before that, the periphery of the screw of the folded plate 3 is deformed under pressure, and the screw 8 is inclined. At this time, part of the burden load applied to the wall panel 1 is changed to a force for inclining the screw 8. And the folded plate 3 will hold the burden load, and the shear yield of the folded plate 3 can be prevented. Therefore, brittle shear yield can be prevented, and toughness can be secured by supporting pressure deformation around the screw of the folded plate 3, and the energy absorption performance of the wall panel 1 can be enhanced. That is, when buckling such as overall buckling or local buckling of the folded plate 3 occurs, the shear stress cannot be maintained, and brittle fracture is caused in which the yield strength is rapidly reduced and deformation is increased. Therefore, the deformation performance of the wall panel 1 can be improved by preventing such buckling. At this time, the shear yield strength determined by the overall buckling of the folded plate 3 is greatly affected by the height of the crest of the folded plate 3, and by setting the crest height to a predetermined value or larger, The shear strength determined by the bearing strength of can be exceeded. Moreover, as the shear yield strength determined by the local buckling of the folded plate 3, the influence of the valley width dimension of the folded plate 3 is large, and the valley width dimension of the folded plate 3 is set by suppressing the valley width dimension to a predetermined value or less. The shear strength determined by the bearing strength around the screw can be exceeded.

According to the wall panel 1 described above, the joint strength at the joint between the folded plate 3, the frame member 2 and the screw 8 is determined by the bearing strength around the screw of the folded plate 3, and it is folded when an external force is applied. The periphery of the screw of the plate 3 is configured to deform under pressure. Thereby, a burden load can be hold | maintained, without carrying out the yield strength fall rapidly by the whole buckling of the folded plate 3, a local buckling, the deformation | transformation of the frame material 2, etc. Therefore, the load can be held up to a relatively large deformation angle (for example, about 1/30 rad in the interlayer deformation angle) without reducing the proof stress of the wall panel 1. That is, since the deformation performance of the folded plate 3 can be enhanced, the structural characteristic coefficient can be set small. Thereby, the number of bearing walls (wall length) can be reduced, and the frame material plate thickness and the strength of the joint hardware can be suppressed, thereby increasing the degree of freedom in economic and architectural planning. That is, by joining the frame member 2 and the folded plate 3 by screwing, the joining structure is simplified, and the labor and cost of manufacturing and construction can be reduced.

And in order to search for surely and stably causing the support pressure deformation of the folded plate 3 by the screw 8 in the screw joint portion, the mechanical properties of the folded plate 3 and the plasticization in the vicinity of the screw joint portion, Tested and examined.

As the test and examination conditions, the following patterns (i) to (iv) are considered as failure modes of the screw joint when a support pressure by pushing and pulling is applied to the screw joint and the screw joint is subjected to bearing deformation. However, it was assumed that the patterns were (i) and (ii).
(I) When the joint of the folded plate 3 is deformed by supporting deformation in the vicinity of the screw joint, and the screw tip of the screw 8 comes off.
(Ii) When the folded plate 3 (face material) is subjected to bearing deformation when the bearing is deformed near the screw joint, and the joint is destroyed.
(Iii) A case where the frame member 2 is subjected to bearing deformation when the bearing is deformed near the screw joint, and the joint is destroyed.
(Iv) When the bearing 8 is deformed in the vicinity of the screw joint, the shaft 8B of the screw 8 is broken and the joint is destroyed.

First, with regard to the _unwinding resistance R _as2 (R _as2 / R _as3-1 ) of the screw 8 with respect to the bearing _support resistance R _as3-1 of the folded plate 3, when R _as2 / R _as3-1 is _less than 1.0, The pull-out resistance R _as2 of the screw 8 is too small, and the tip of the screw 8 is easily pulled out of the frame member 2. On the other hand, _if the value of R _as2 / R _as3-1 is too large, the screw 8 does not move, and the head portion 8 A of the screw 8 enters the folded plate 3. In any of these cases, the inclination of the shaft portion 8B of the screw 8 cannot be ensured, and the folded plate 3 of the screw joint portion 8C is stably plastically deformed to absorb energy, thereby preventing a sudden decrease in the proof stress of the bearing wall. I can't do that. Therefore, in the wall panel 1 of the present invention, the ratio of the proof resistance of the screw 9 to the bearing strength of the folded plate 3 (R _as2 / R _as3-1 ) is the shaft portion of the screw 8 when the folded plate 3 is deformed by bearing pressure. 8A is set to the predetermined value which inclines. Thereby, it is possible to prevent the screw 8 from slipping out of the frame member 2 and the screw 8 (particularly, the head 8A) from entering the folded plate 3. Moreover, it is preferable that the ratio of the pullout yield strength of the screw 9 to the bearing strength of the folded plate 3 is 0.7 or more. Thereby, it can prevent that the front-end | tip of the screw 8 comes off from the frame material 2 before the screw 8 inclines. Also. The ratio of the pull-out resistance of the screw 9 to the bearing strength of the folded plate 3 is preferably 1.6 or less. As a result, the screw 8 can be inclined without the screw 8 entering the folded plate 3.
However, when a washer described later is used, the ratio of the proof stress of the screw 8 to the bearing strength of the folded plate 3 may be in the range of 0.7 to 4.0.

In order to estimate the yield strength and deformation performance of the wall panel 1, an element test was performed on the screw joint.

FIG. 7A shows the state of the element test of the screw joint portion. The element loading test apparatus 14 includes a first force applying jig 16 having a bifurcated mounting arm 15 on one side and a thick plate connecting steel plate on the other side. And a second force applying jig 17 having.

The both ends of the folded plate piece 3a, which is a part of the folded plate 3, are arranged so that the fold line is directed along the bifurcated direction of the arm 15. The face material 3 of the trough 7 in the direction of the folding line is fixed by fixing bolts 19 through three washers 18 respectively. The web 4 on one end side of the frame member piece 2a which is a part of the frame member 2 is joined to the lower surface of the central portion of the folded plate piece 3a by a screw 8 such as a screw. The other end portion of the frame member piece 2 a is superposed on one end portion of the thick plate connecting steel plate 20 and fixed by three bolts 19. Further, the other end of the thick plate connecting steel plate 20 is superposed on the second pressure jig 17 and fixed by a washer and three bolts 19.

Four types of folded plate element pieces having different shapes and thicknesses of the test piece of the folded plate piece 3a were manufactured and tested. As shown in FIG. 7A by arrows, the loading on the folded plate piece 3a was applied with a positive and negative incremental increase load by a hydraulic jack or the like (not shown).

The conditions for the folded plate piece 3a, the frame member piece 2a, and the screw 8 in the test are as follows.
(I) The cross-sectional shape of the folded plate piece 3a is the shape shown in FIG.
(Ii) The frame piece 2a is SGC400 and has a plate thickness of 1.6 mm, the web width dimension is 89 mm, and the flange width is 44.5 mm.
(Iii) The screw 8 that joins the folded plate 3 and the frame member 2a in one place is a hexagonal head screw having a nominal diameter of 4.8 mm, and extends over the folded plate 3 and the frame member 2a. And it screwed in and joined to the trough part 7 of the folded plate 3 until the hexagon head contacted.

Each specimen of the folded plate piece 3a is a specimen using four types of steel materials as shown in Table 1. The load-displacement relationship obtained in this test is shown in FIGS. 9A and 9B.

The specimen of the steel material B has a ratio of the proof stress of the screw 8 to the bearing strength of the face material 3 of 0.68, and exhibits sufficient deformation performance. As a result, the lower limit of the ratio of the yield strength of the screw 8 to the bearing strength of the face material 3 was set to 0.7. In addition, the steel material B2 test body has the same surface material 3 and screw diameter as the steel material B test body, but the frame material 2 is overlapped to increase the pull-out resistance of the screw 8, and the screw 8 is less inclined. ing. The specimen of the steel material B2 has a deformation ratio of 1.66, which is a ratio of the yield strength of the screw 8 to the bearing strength of the face material 3, which is 1.66. The specimen of the steel material A has a ratio of the pull-out resistance of the screw 8 to the bearing capacity of the face material 3 of 1.44, and exhibits sufficient deformation performance. Accordingly, the upper limit of the ratio of the yield strength of the screw 8 to the bearing strength of the face material 3 was set to 1.6. This upper limit is a numerical value when a commercially available screw is used, and the upper limit becomes higher when a large-diameter washer described later is used.

The specimen D of the steel material D was poor in deformation performance even though the ratio of the yield strength of the screw 8 to the bearing capacity of the face material 3 was higher than that of the steel B specimen. This is because the steel material B is a special low fracture elongation steel and the fracture mechanism is different. When considering only the general steel material D, it is considered that the lower limit of the ratio of the yield strength of the screw 8 to the bearing strength of the face material 3 is increased.

In general, for example, when R _as3-1 << R _as2 and the screw 8 does not tilt at the screw joint portion, as shown in FIG. The steel plate portion in the folded plate 3 around is removed. That is, the steel plate portion is gathered in a small manner so as to form the bent portion 22 on the front side or the side surface, and the bent portion 22 becomes a resistance and the proof stress is increased. Then, the steel plate floats in the out-of-plane direction (the head 8A of the screw 8 sinks into the face material 3), and as a result, the strength of the folded plate 3 and the strength of the wall panel 1 become unstable.

As described above, it was found that the face material 3 may be subjected to bearing deformation even when the screw pull-out resistance is smaller than the face material bearing fracture resistance.

10B and 10C, when the face material 3 around the screw hole 9 in the face material (folded plate 3) is loaded and deformed by the screw 8, the screw 8 is inclined. As a result, the face material 3 supported by the screw hole in contact with the shaft portion 8B of the screw 8 is turned up along the inclination of the shaft portion 8B of the screw 8. In the face material with high elongation at break (folded plate 3), a crack 23 enters the top of the turned up part, and the screw 8 comes out. Further, it was found that, at low breaking elongation, cracks 23 were formed at the skirt of the turned up part and removed as chips 26 as shown in FIG. 10D.

Further, as described above, when the screw 8 is inclined and the folded plate 3 is made of a material having a high breaking elongation, as shown in FIG. 10B, when the support plate is deformed by the shaft portion 8B of the screw 8, The plasticized portion 21 clings to the shaft portion 8B. As a result, the load on the 8B shaft portion of the screw 8 is increased, the proof stress of the face member 3 is increased, and the proof stress of the wall panel 1 is increased, but the screw 8 comes out of the frame member 5. On the other hand, when the folded plate 3 is made of a material having low elongation at break, it is brittle and, as shown in FIGS. 10D and 10E, a portion (particularly, a screw) that is supported and deformed by the shaft portion 8B of the screw 8. The folded plate 3 on the front end side of 8 is crushed into chips 26. As a result, the supporting pressure (load) acting on the screw 8 is unchanged and stabilized, and the proof stress of the wall panel 1 is stabilized.

Specifically, when the elongation at break is smaller than 15.9% as in the steel material B in Table 1 above, as shown in FIG. The plasticized portion 21 of the face material 3 is not collected at the tip of the screw hole 9 that contacts the screw 8. That is, since the collected face material 3 of the steel plate is easily crushed and eliminated, the plasticized face material 3 gathered around the screw hole 9 does not resist the screw 8. Thereby, the face material 3 can be stably plastically deformed, and stable proof stress can be exhibited.

The effect of elongation at break when a steel plate is used as the folded plate 3 will be examined based on the models shown in FIGS. 11A and 11B.

As shown in FIG. 11A, in order for the steel sheet riding on the shaft 8B of the screw 8 to be crushed into chips, the elongation of the outer peripheral surface with respect to the thickness center of the steel sheet must be equal to or greater than the breaking elongation El of the material. Therefore, it is necessary to satisfy the following expression (13).
_{(D 1/2 + t 1} ) / (d 1/2 + t 1/2) -1> El ... (13)

For example, from the above experiment, it is understood that when the shaft diameter d ₁ of the shaft portion 8B of the screw 8 is 4.8 mm and the plate thickness t _{1 of the} steel plate is 0.6 mm, El needs to be 11% or less. .

According to equation (13), shaft diameter d ₁ of the screw 8 is small, the thickness t ₁ of the steel sheet by increasing, it is possible to raise the upper limit of the elongation at break. In the case of a steel house of about 3 stories or less, d ₁ is 4.2 mm or more and t ₁ is 0.8 mm or less, so the upper limit of elongation at break is obtained by the following equation (13a).
(4.2 / 2 + 0.8) / (4.2 / 2 + 0.8 / 2) -1 = 0.16> El (13a)

As a result of numerical calculation analysis by the formula (13), it is desirable that the breaking elongation of the folded plate 3 is less than 16%. By using the folded plate 3 having a small breaking elongation, when the face material 3 around the shaft portion 8B of the screw 8 supported by the shaft portion 8B of the screw 8 is plasticized, the shaft portion 8B of the screw 8 is inclined. When it rises along, it is crushed and easily removed. On the other hand, if the elongation at break of the face material 3 is less than 1%, cracks are likely to occur during folding plate processing, which is not desirable. If the elongation at break of the face material 3 exceeds 16%, it becomes difficult to grind, which is not desirable.

Therefore, when the breaking elongation of the steel material constituting the folded plate 3 is less than 16%, the steel plate of the folded plate 3 around the screw hole 9 is plasticized by the shaft portion 8B of the screw 8 and gathers at the tip of the screw 8. The steel material of the folded plate 3 is crushed and does not cling to the shaft 8B of the screw 8. As a result, resistance to the formation of the screw hole 9 elongated in the bearing direction by the shaft portion 8B of the screw 8 can be eliminated, and deformation performance can be ensured while stabilizing the yield strength of the folded plate 3 and the wall panel 1.

Next, a literature survey was conducted on the effects of using washers for screws. Figure II. Effective information was obtained from 5.12. FIG. 12 shows the stress distribution around the bolt hole, and FIG. 13 shows the stress value depending on the distance from the bolt core. As shown in FIG. 13, when the distance from the bolt center is within three times the bolt radius, the stress change gradient is large. Therefore, by using a washer in this range, it is possible to suppress the screw head from entering the face material. Further, as shown in FIG. 13, it can be seen that the higher the yield ratio YR of the steel sheet (indicated by β in FIG. 13), the greater the stress change gradient and the narrower the plasticization region.
As shown in FIGS. 14A and 14B, the ratio of the outer diameter Dw of the washer 33 divided by the shaft diameter d ₁ of the shaft portion 8B of the screw 8 (outer diameter Dw / shaft diameter d ₁ of the shaft portion 8B of the screw 8). The value is 3.0 or more, and it is considered that a sufficient effect can be obtained. Indeed, the shaft diameter _{d 1} of the shaft 8B Whereas screw 8 of 4.2 mm, using an outer diameter 21mm washer 33 is five times the shaft diameter _{d 1} of the shaft portion 8B of the screw 8, in FIG. 7A The element test of the screw joint part by the apparatus shown and the wall panel loading test by the apparatus of FIG. As a result, when the washer 33 was not inserted, as shown in FIG. 10A, the head portion 8A of the screw 8 entered under the face material 3 and could not hold the proof stress, and the load bearing wall 1 was severely deteriorated. On the other hand, when the washer 33 was inserted, each screw 8 retained the yield strength, and the yield strength could be retained even when the entire bearing wall 1 was greatly deformed.
In addition, the bearing deformation of the face member 3 fixed to the vertical frame member 2A disposed on both ends is larger than that of the horizontal frame member 2B. Therefore, the washer 33 may be inserted only into the screw 8 that fixes the vertical frame member 2 </ b> A shown in FIG. 1 to the valley portion 7 of the face member 3. Thereby, the overall manufacturing cost can be suppressed while stably securing the bearing deformation around the screw 8 in the face material 3.

Further, the inclination of the screw 8 due to the gap (clearance) between the hole 33a of the washer 33 and the shaft portion 8B of the screw 8 will be described. That is, as shown in FIG. 14A, it is preferable that a gap is formed between the hole 33a of the washer 33 and the shaft portion 8B of the screw 8. According to this configuration, since the screw 8 is tilted using this gap, the tilt angle range of the screw 8 is limited when the periphery of the screw 8 of the face material 3 is subjected to bearing deformation. Thereby, it can suppress that the screw | thread 8 slips out from the frame material 2. FIG.
Further, as shown in FIG. 14A, if the clearance is small, the screw 8 and the washer 33 are integrated only by slightly deforming the face material 3, and the lifting of the washer 33 is suppressed. Accordingly, a local buckling bent line of the valley portion 7 of the folded plate 3 is generated from the outer edge of the washer 33 as indicated by a black dot in FIG. 14A. On the other hand, as shown in FIG. 14B, when the clearance is large, the screw 8 and the washer 33 are inclined independently until the folded plate 3 is largely deformed, and the lifting of the washer 33 is not suppressed. Accordingly, a local buckling bent line of the valley portion 7 of the folded plate 3 is generated from the center of the screw 8 as indicated by a black dot in FIG. 14B. That is, if the distance to the end of the valley 7 of the folded plate 3 is the buckling length, if the clearance is large, local buckling of the valley 7 of the folded plate 3 is likely to occur early. . Therefore, (the difference between the shaft diameter _{d 1} of the shaft portion 8B inside diameter dw and the screw 8 of the washer 33) clearance with respect to the thickness tw of the washer 33, i.e., shaft diameter from the inner diameter of the washer 33 of the shaft 8B of the screw 8 The value of (dw−d ₁ ) / tw, which is a ratio obtained by dividing the difference obtained by subtracting the dimension by the thickness dimension of the washer 33, is preferably 0.1 to 0.6. Actually, a washer 33 (Dw = 18 mm, dw = 5.5 mm, tw = 2.0 mm) with a value of (dw−d ₁ ) / tw of 0.13 and a washer 33 (Dw = 21 mm, dw) of 0.65 = 4.5 mm, tw = 2.3 mm), an element test of the screw joint 8C by the apparatus shown in FIG. 15A and a wall panel loading test by the apparatus shown in FIG. As a result, when the clearance was smaller, wrinkles of the folded plate 3 occurred from the outer peripheral edge of the washer 33, and local buckling of the valley portion 7 of the folded plate 3 was suppressed. On the other hand, when the clearance was larger, wrinkles of the folded plate 3 were generated from the screw holes, and local buckling of the valley portions 7 of the folded plate 3 occurred early.

FIG. 15A shows the state of the element test of the screw joint. The apparatus shown in FIG. 7 replaces the positions of screws and fixing bolts with respect to the apparatus shown in FIG. 7A.

As the folded plate piece 3a, five types of folded plate element pieces having different shapes and thicknesses were manufactured and tested.

In the test, the conditions of the folded plate piece 3a, the frame material piece 2a, and the screw 8 are as follows.
(I) the cross section of the folding plate piece 3a is a surface material shape, a shape shown in FIG. 16, SGC400 of 0.55 mm (yield point 373N / mm ^2, a tensile strength of 505N / mm ^2, elongation at break 32%) and did.
(Ii) As the frame member 2a, SGC400 having a plate thickness of 1.6 mm was used. The web width dimension was 89 mm, and the flange width was 44.5 mm.
(Iii) As the screw 8 for joining the folded plate 3 and the frame piece 2a at one place, a hexagon head screw having a nominal diameter of 4.2 mm was used. And this screw 8 was screwed and joined to the trough part 7 of the folded plate 3 until the hexagon head contacted across the folded plate 3 and the frame material piece 2a.

For each test piece of the folded plate piece 3a, five types of steel materials as shown in Table 2 were used. The load-deformation relationship obtained in this test is shown in FIGS. 17A and 17B.

As shown in FIG. 17A, the specimen of the steel material E1 exhibits a sufficient deformation performance because the ratio of the proof stress of the screw 8 to the bearing strength of the folded plate piece 3a which is a face material is 1.32. . On the other hand, the steel E2 test body in which two frame material pieces 2a are stacked has a ratio of the proof stress of the screw 8 to the bearing strength of the folded plate piece 3a, which is a face material, as high as 3.16. Was scarce. On the other hand, with respect to the test body of steel E2, the test body of steel E3 having a washer outer diameter of 21 mm and a clearance between the washer inner diameter and the screw shaft diameter of 0.3 mm exhibited sufficient deformation performance. From this result, it was found that by using an appropriate washer, the upper limit of the ratio of the pull-out strength of the screw 8 to the bearing strength of the folded plate piece 3a that is a face material can be relaxed.
As shown in FIG. 17B, there is no clearance between the washer inner diameter and the screw shaft diameter (the washer has only a small tip hole, and the washer itself is threaded with a screw and integrated with the screw). The shaft portion of the screw was broken with a small deformation as compared with the specimen E4 having a clearance of 0.3 mm, and the deformation performance was poor. From this result, an appropriate clearance is required to secure the deformation performance, and in the experiment, the clearance with respect to the washer thickness was 0.15 (= 0.3 / 2.0). The lower limit value of the ratio obtained by dividing the difference obtained by subtracting the shaft diameter of the screw shaft by the thickness of the washer was 0.1.

FIG. 18 shows a wall strength test body as a basis for setting an upper limit value of the ratio obtained by subtracting the shaft diameter of the screw shaft from the inner diameter of the washer by the thickness of the washer. FIG. 19 shows the load-deformation angle relationship obtained using the load test apparatus of FIG. As shown in FIG. 18, screws with washers were used only on the left and right ends of the outer periphery, and screws without washers were used for the other bearing walls. That is, as described above, the washer 33 is inserted only into the screw 8 that fixes the vertical frame member 2A to the face member 3 having a large bearing deformation. Surface material of the specimen of the specimen and steel E7 steel E6 are identical, SGC400 of 0.55 mm (yield point 373N / mm ^2, a tensile strength of 505N / mm ^2, elongation at break 32%), the outer diameter of the washer Is 18 mm, the washer thickness is 2.0 mm, and only the clearance is an experimental variable. The clearance of the steel E6 is 0.3 mm, and the clearance of E7 is 1.3 mm. As a result of the loading, the two bodies have almost the same proof stress, but the steel material E7 having a larger clearance has lower rigidity, and local buckling (crease) occurs around the screw in the folded plate valley before the deformation angle of 1/100 rad, Lost proof. From this experiment, since the clearance with respect to the washer thickness of the steel material E7 was 0.65 (= 1.3 / 2.0), the difference obtained by subtracting the shaft diameter of the screw shaft from the inner diameter of the washer was calculated. The upper limit of the ratio divided by the thickness dimension of the washer was 0.6.

When the folded plate 3 is fixed to the frame member 2 on the back surface side thereof by using a screw 8 such as a drilling tapping screw, the thread pitch P of the screw 8 such as a drilling tapping screw is the plate thickness of the flange 5 in the frame member 2. If it exceeds the dimension, the screw thread will not catch on the frame material at 360 degrees all around. As a result, as shown in FIG. 20, when the screw 8 is inclined, the resistance force cannot be exerted, and the risk of the screw 8 coming out increases.

Therefore, if the pitch of the screw threads of the screw 8 in the screw joint portion 8C is equal to or less than the plate thickness dimension of the frame member 2, the screw thread in the frame member 2 even when the screw 8 is inclined in the screw joint portion 8C. It can be caught at 360 degrees around the entire circumference, preventing the screw 8 from coming off from the frame member 2, and exhibiting a stable proof stress.

Drilling tapping screws with nominal diameters of 4.8 mm, 6.0 mm, and 8.0 mm are known, but the thread pitch is 1.6 mm when the nominal diameter is 4.8 mm, and the nominal diameter is The nominal diameter and pitch are not proportional to 6.0 mm and 1.8 mm, and the nominal diameter is 8.0 mm and 1.0 mm. Therefore, it is preferable to use a screw 8 having a smaller thread pitch than the thickness of the flange 5 of the frame member 2.

As shown in FIG. 21, when a screw 8 having a sharp tip 8D is used, the frame material 2 in a portion extruded (burring) into a cylindrical shape by the tip 8D of the screw 8 is bent and screw shaft portions are formed. Along 8B. Thereby, the hooking part of the frame material 2 with respect to the screw shaft part 8B becomes large (the number of threading hooks increases). Therefore, even if the pitch of the screw thread is larger than the plate thickness of the frame member 2, it is possible to prevent the screw 8 from coming out, so that the tip 8D is sharply formed especially when the plate thickness of the frame member 2 is thin. Use of screws is effective.

As shown in FIG. 22, a comparative test by a load test for pushing and pulling was performed on a wall panel using a folded plate made of three kinds of steel, for the bearing deformation of the folded plate 3 by a screw at the screw joint.

Each wall panel 1 was joined to a lower side applying jig 27 via a hole down hardware 26 joined to both sides of the lower side. The upper part of the wall panel 1 was joined to a loading beam 29 attached to a loading jig 28 on the upper side, and loaded by pushing and pulling a loading jack 30 joined to the loading beam. The shape of the test body and the shape of the folded plate are the same as in FIG. 18, but all the screws in which the folded plate is joined to the frame member are screws without washer. The load-deformation angle relationship obtained from loading is shown in FIG. The deformation angle in FIG. 23 is the inclination of the wall panel 1 calculated from the two displacement meters 32 in FIG.

As a result of testing the influence of the wall panel 1 as the bearing wall, depending on the strength of the steel material and the yield ratio YR, the results shown in Table 3 below were obtained. In addition, steel materials A and B in Table 3 below are the same as the steel materials shown in Table 1 above. Further, the ultimate deformation angle Ru in Table 3 is the deformation angle at the proof stress reduced to 80% of the maximum proof stress.

The ultimate deformation angle Ru of the wall panel 1 using the steel materials A and B was 1.3 times or more larger than the ultimate deformation angle Ru of the wall panel 1 using the steel material C.

In FIG. 24A, when a force is applied in the direction of shifting in the frame surface between the frame member 2 and the face member 3 when a supporting pressure is applied to the face member 3 of the low YR from the shaft portion 8B of the screw 8. The state of the action of the force and the state of deformation are shown. The crack propagation direction is a direction spreading around the screw 8. When the frame member 2 and the face member 3 are deviated from this state, as shown in FIG. 24B, the breaking line 12 is entirely spread in the direction opposite to the crack propagation direction, and the long hole 10 is formed. Further, the face material 3 is plastically deformed, and wrinkles 13 are generated in the crack propagation direction.
On the other hand, when the supporting pressure is applied to the high YR face material 3, the crack propagation direction goes straight as shown in FIG. 24C. When the frame material 2 and the face material 3 are deviated from this state, as shown in FIG. 24D, the fracture line 11 spreads straightly in the direction opposite to the crack propagation direction. At this time, the long hole 10 to be formed is smaller when the high YR face material 3 is used than when the low YR face material 3 is used.
That is, from the test results of the face material of the high yield ratio steel (high YR steel) as described above and the face material of the low yield ratio steel (low YR steel), as shown in FIG. 24C and FIG. The higher steel folded plate may suppress the spread of the plasticized region of the steel material around the screw hole and ensure stable bearing deformation.

From this result, by increasing the yield ratio YR of the steel material of the folded plate 3 as the face material, for example, by setting the yield ratio YR to 77% or more (the yield ratio of the steel material is at least 77%), the screw shaft portion rotates around the screw shaft. When the face material is plasticized, the plasticized region around the screw hole can be suppressed. Thereby, even if the screw head does not come out and the periphery of the screw hole becomes plastic, a narrow screw hole can be formed, and the yield strength can be stabilized.

The influence of the yield ratio when a steel plate is used as the folded plate 3 as the face material will be examined from the model shown in FIG. 25A.

From FIG. 25B, it is assumed that the angle θ is a range in which the face material (the valley portion 7 of the folded plate 3) in contact with the shaft portion of the screw can bear the proof stress, and B is the width of the yield region formed at the maximum proof stress. The following expressions (14a) and (14b) hold.
_{d 1/2 · θ · F} u1 = B · F 1 ... (14a)
_{B = d 1/2 · θ} · F u1 / F 1 ... (14b)

In order to prevent the shaft portion 8B of the screw 8 from coming out of the screw hole 9, the width B of the yield region may be set to be equal to or less than the diameter of the screw, so that the following expressions (14c) to (14g) must be satisfied.
d ₁ > B (14c)
_{d 1> B = d 1/} 2 · θ · F u1 / F 1 ... (14d)
θ / 2 <F ₁ / F _u1 (14e)
Here, if θ = 90 °, π / 4 <F ₁ / F _u1 (14f)
_{0.785 <F 1 / F u1 ...} (14g)

As a result of numerical calculation analysis by the equation (14e), it is desirable that the yield ratio (F ₁ / F _u1 ) of the folded plate is 79% or more. However, in the experiment, even with less than 77% of steel A, the wall panel was deformable. This is because it is assumed that the face material in the portion in contact with the screw 8 bears stress uniformly, and that the angle θ in the range where the face material can bear the proof stress is assumed to be 90 °, etc. It is thought to be due to. Therefore, it is understood that the yield ratio should be 77% or more based on the experimental values. In the folded plate 3 having a yield ratio of less than 77%, the plasticization region is widened and the hole width is widened, so that the screw (particularly, the head portion of the screw) can easily enter the face material. Therefore, it can be seen that the yield ratio of the folded plate 3 should be 77% or more. Moreover, although there is no upper limit in particular, since it is confirmed up to 96% by the experimental value, about 96% is desirable.

Therefore, when the folded plate 3 (for example, the yield ratio is 77% to 96%) 3 as a face material having a high yield ratio is used, the steel plate in the valley portion of the folded plate 3 supported by the screw 8 in the screw joint 8C is obtained. When plasticized and deformed, the plasticized region becomes about the screw hole diameter. That is, since the hole width of the screw hole does not widen, the proof stress can be stabilized even when deformed, and the wall panel can be stable even if deformed.

Further, from the test as described above, it is possible to stably form the support plate deformation (plasticization) of the folded plate 3 by the shaft portion 8B of the screw 8 at the screw joint portion 8C, in other words, the elongated screw hole. In order to ensure, a method of increasing the rigidity of the portion other than the portion to be plasticized, limiting the portion to be plasticized, and preventing the generation of wrinkles 13 shown in FIG. 24B around the screw 8 is effective. It is thought that. This configuration will be described with reference to FIGS. 26A to 26C and FIGS. 27A to 27D.

First, in the form shown in FIGS. 26A to 26C, the extending direction of the valley portion 7 (folded plate 3 around the screw 8 is centered on the screw hole of the folded plate 3 through which the shaft portion 8B of the screw 8 is inserted. Ribs 24 extending in a direction perpendicular to the extending direction of the valley portion 7 are provided on both sides of the screw joint portion 8 </ b> C along the crease line direction). Thereby, local buckling which the wrinkles 13 generate | occur | produce in the surface material of the direction orthogonal to the direction in which the folded plate 3 plasticizes can be prevented. Further, the face material can be plasticized in a predetermined direction in the bearing wall.

The rib 24 may be formed at the same time when the folded plate 3 is press-molded. After the folded plate 3 is rolled, only the rib 24 portion is formed by pressing. May be. The processing length of the rib 24 may be greater than the diameter of the screw hole and close to the vicinity of the peak portion 6. The ribs 24 are provided on one side or both sides where wrinkles are expected to occur during plasticization.

In the form shown in FIGS. 27A to 27D, valleys are formed on both sides of the folded plate 3 around the screw hole 31 through which the shaft portion 8B of the screw 8 is inserted and along the direction perpendicular to the extending direction of the valley portion 7. A thin plate portion (thin wall portion) 25 having a plate thickness dimension smaller than the plate thickness of the portion 7 is formed. Thereby, the intensity | strength of the thin-plate part 25 falls and it becomes a low intensity | strength part. As a result, when the periphery of the screw 8 of the folded plate 3 is plasticized by the screw 8, the thin plate portion 25 is plasticized. In this way, by limiting the plasticizing range to a specific place, it is possible to suppress the generation of wrinkles in the folded plate 3, and the effect of stabilizing the proof stress of the bearing wall 1 can be obtained. In the illustrated form, the means for forming the thin plate portion 25 so as to connect to the screw hole 31 may be formed simultaneously with the press forming of the folded plate 3. For example, after the folded plate 3 is rolled, only the thin plate portion 25 may be processed and formed. As the processing method, it is considered that press processing or cutting processing is suitable. The processing width of the thin plate portion 25 is about the diameter of the screw hole 31, and the length may be formed up to the vicinity of the peak portion 6.

The thin plate portion 25 may be formed by providing a concave portion by cutting or the like on the surface side of the valley portion 7. Moreover, you may make it form by providing a recessed part in the back surface side of the trough part 7 by cutting. Furthermore, you may make it form by providing a recessed part in the front and back both surfaces of the trough part 7 by cutting. When the thin plate portion 25 is a concave portion formed on the surface side of the valley portion 7, the concave portion can be used for positioning when the screw 8 is screwed in when the screw is screwed.

The portion to be plastically deformed by supporting the shaft 8B of the screw 8 may be used as the thin plate portion 25 to reduce the strength. The material strength may be reduced by heat treatment or chemical treatment without changing the plate thickness. Alternatively, a low strength portion may be formed.

That is, in the direction orthogonal to the extending direction of the trough 7 centering on the screw hole 31 of the folded plate 3 through which the shaft portion 8B of the screw 8 is inserted (near the screw hole 31 of the trough 7 of the folded plate 3). You may provide the intensity | strength reduced part which reduced the intensity | strength rather than the intensity | strength of the trough part 7 on the both sides along. According to this configuration, when the periphery of the screw 8 of the folded plate 3 is plasticized by the screw 8, the strength-decreasing portion is plasticized. Thus, by limiting the plasticizing range to a specific place, the proof stress of the wall panel 1 can be stabilized even when the folded plate 3 is greatly deformed. Further, the position of the screw hole 31 is preferably provided in the thin plate portion 25 as shown in FIGS. 27C and 27D.

The above-mentioned steel house is usually defined as a steel panel structure building that is constructed by combining a frame material made of a thin lightweight steel with a thickness of 0.4 mm or more and less than 2.3 mm and a structural face material. .

In addition, if high yield point (high YP) steel is used as the folded plate 3 or the frame member 2, the weight can be reduced. As described above, when a steel material having a high yield ratio (high YR) is used for the folded plate 3, the proof stress is stabilized with respect to the loaded load at the time of bearing deformation at the screw joint portion 8C, and the proof stress is suddenly lowered or rapidly increased. No increase in proof stress occurs. As a result, the wall panel 1 as the load bearing wall can exhibit stable strength at the screw joint. Further, when the folded plate 3 is made of a steel material having a low elongation at break (low El), a long and narrow screw hole is formed without causing a sudden decrease in the proof stress, so that the deformation performance of the wall panel 1 can be easily secured.

The present invention can be applied to a wall panel for building a thin plate lightweight section steel that constitutes a building such as a thin plate lightweight section steel building.

1 Wall Panel 2 Frame Material 2a Frame Material Piece 3 Folded Plate (Face Material)
3a Folded plate piece 4 Web 5 Flange 6 Mountain portion 7 Valley portion 8 Screw 8A Head portion 8B Screw shaft portion 8C Screw joint portion 8D Tip 9 Screw hole 10 Long hole 11 Break line 12 Break line 13 Wrinkle 14 Loading test device 15 Arm 16 First loading jig 17 Second loading jig 18 Washer 19 Bolt 20 Thick plate connecting steel plate 21 Plasticizing portion 22 Bending portion 23 Crack 24 Rib 25 Thin plate portion 26 Hole down hardware 27 Lower side loading jig 28 Upper portion Side loading jig 29 Loading beam 30 Loading jack 31 Screw hole 32 Displacement meter 33 Washer 33a Hole

Claims (14)

1. A pair of frame members arranged opposite to each other at intervals;
   A face material which is a folded plate of thin steel plates fixed to these frame members and having crests and troughs alternately formed from one to the other;
   A screw for fixing the valley portion of the face material to each frame member;
   When the in-plane shear force is applied to each frame member, a wall panel for a load bearing wall in which the peripheral portion of the screw of the face member is subjected to bearing deformation and resists,
   The wall panel according to claim 1, wherein a ratio of the unscrewing yield strength of the screw to the bearing strength of the face material is set to a predetermined value at which the shaft portion of the screw is inclined when the bearing material is deformed by bearing pressure.
2. The wall panel according to claim 1, wherein the predetermined value is 0.7 or more.
3. The wall panel according to claim 1 or 2, wherein the predetermined value is 1.6 or less.
4. A washer into which the screw is inserted;
   The wall panel according to claim 1 or 2, wherein a ratio obtained by dividing the outer diameter of the washer by the shaft diameter of the shaft portion of the screw is 3.0 or more.
5. The wall panel according to claim 4, wherein the predetermined value is 4.0 or less.
6. The frame member includes a first frame member arranged in the extending direction of the valley part, and a second frame member arranged in a direction orthogonal to the extending direction of the valley part,
   A square frame is formed by the first frame material and the second frame material,
   The wall panel according to claim 4, wherein the washer is inserted only into the screw that fixes the first frame member to the valley portion of the face material.
7. The wall panel according to claim 4, wherein a gap is formed between the hole of the washer and the shaft portion of the screw.
8. The ratio obtained by subtracting the shaft diameter of the shaft portion of the screw from the inner diameter of the washer divided by the thickness of the washer is 0.1 to 0.6. Wall panels as described in.
9. The wall panel according to claim 1, wherein the elongation at break of the face material is 1% or more and less than 16%.
10. The wall panel according to claim 1, wherein a pitch of a thread of the screw is equal to or less than a plate thickness dimension of each frame member.
11. 2. The wall panel according to claim 1, wherein the yield ratio of the face material is 77% to 96%.
12. A rib perpendicular to the extending direction of the valley portion is further provided on at least one side along the extending direction of the valley portion with the screw hole through which the shaft portion of the screw is inserted as a center. The wall panel according to claim 1, wherein the wall panel is formed.
13. Thin portions with a small plate thickness are formed on both sides of the face material along the direction orthogonal to the direction in which the valley extends, with the screw hole through which the shaft portion of the screw is inserted as the center. The wall panel according to claim 1, wherein the wall panel is provided.
14. Low in mechanical strength partially lower than the surroundings on both sides of the face material along the direction perpendicular to the direction in which the trough extends, centering on the screw hole through which the shaft portion of the screw is inserted. The wall panel according to claim 1, wherein a strength portion is formed.
    
    

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