Vibration damper for wooden structures and vibration damping structure for wooden structures

Abstract

To provide a vibration damper for wooden structure body which can absorb vibration energy efficiently as a whole, and to provide a vibration damping structure for wooden structure body.SOLUTION: A vibration damper for wooden structure body includes: a pair of left and right joint metals 5 provided being in contact with a pair of wooden vertical materials 2 respectively, and separated from each other in the left-to-right lateral direction; a damping member 6 arranged between these joint metals, and having a pair of joint parts 6a at left-to-right lateral direction both end parts; and a pair of left and right connection members 7 in which one end part 7a is joined to each joint part of the damping member and the other end part 7b is connected to the pair of joint metals, and which connects each joint part of the damping member to each joint metal. The damping member is formed by a steel flat plate material, and has each joint part of the left-to-right lateral direction both end parts and a body part (constricted part 8) between these joint parts, and an outer shape contour of the body part toward a left-to-right lateral direction central part from each joint part is defined by a curve C determined by a combination stress of a plastic section modulus and a shearing stress.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a vibration damper for a wooden structure and a vibration control structure for a wooden structure that can efficiently absorb vibration energy as a whole. [Background technology]

[0002] Generally, as a damper that absorbs vibration energy acting on a structure, for example, Patent Document 1 is known. The "seismic damper" of Patent Document 1 aims to provide a seismic damper that can suppress the loss of cumulative deformation capacity, and the yield shear force in the in-plane direction is smallest at a position shifted from the base of the column to the center and is largest at the center. In other words, the yield shear force of the column is smallest at a position shifted from the base to the center for deformation in the in-plane direction (width direction), so the dangerous cross-sectional position is a position shifted from the base of the column to the center. The yield shear force in the out-of-plane direction is smallest at the end of the column in the X direction and is largest at the center. In other words, the yield shear force of the column is smallest near the base for deformation in the out-of-plane direction (thickness direction), so the dangerous cross-sectional position is near the base of the column. In this way, in this embodiment, the dangerous cross-sectional position in the in-plane direction deformation is set to a position shifted toward the center of the column with respect to the dangerous cross-sectional position in the out-of-plane direction deformation. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-25674 A Summary of the Invention [Problem to be solved by the invention]

[0004] The background art is such that when deformation occurs in a seismic damper due to external vibration forces, the dangerous cross-sectional positions are made different for in-plane deformation and out-of-plane deformation, thereby preventing the loss of deformation capacity.

[0005] However, in designing the vibration damper, the deformation parts for in-plane and out-of-plane deformation are separated, so the range in which vibration energy can be effectively absorbed for each deformation is small. Also, because only the plastic section modulus is taken into consideration, only a part of the entire vibration damper contributes to absorbing vibration energy, and the plastic deformation capacity of the vibration damper is not fully utilized. When excessive deformation occurs due to external vibration force, partial stress concentration occurs, and there is a risk of early fracture.

[0006] The present invention has been devised in consideration of the above-mentioned conventional problems, and aims to provide a vibration damper for wooden structures and a vibration control structure for wooden structures that can efficiently absorb vibration energy as a whole. [Means for solving the problem]

[0007] The vibration damper for wooden structures according to the present invention is a vibration damper that is installed in a horizontal direction between the upper and lower height-wise middle parts of a pair of wooden vertical members adjacent in the horizontal direction in a wooden structure formed by joining the upper and lower ends of a plurality of wooden vertical members to upper and lower horizontal members, and is characterized in that it comprises a pair of left and right connecting metal members that are connected to each of the pair of wooden vertical members and spaced apart from each other in the horizontal direction, a damping member that is arranged between the connecting metal members and has a pair of joints at both left and right horizontal ends, and a pair of left and right connecting members that are one end connected to each joint of the damping member and the other end connected to each of the pair of connecting metal members, and that connect each joint of the damping member to each of the connecting metal members, and the damping member is formed of a flat steel plate material, has each joint at both left and right horizontal ends and a main body portion between these joints, and the outer contour of the main body portion from each of the joints toward the left and right horizontal center is defined by a curve determined by the combined stress of the plastic section modulus and the shear stress.

[0008] The curve that defines the outer contour of the main body is characterized by being determined by the Mises yield criterion.

[0009] The damping member is characterized in that the vertical dimension of each joint portion of the damping member is formed to be larger than the vertical dimension of the main body portion.

[0010] The damping member is characterized in that the yield strength of the main body portion is smaller than the yield strength of each of the connecting member and the metal joint.

[0011] The connecting metal is characterized in that it is a steel plate-like material having a vertical member joint formed in the vertical direction of the wooden vertical member and joined to the wooden vertical member, a connecting member joint protruding from the vertical member joint toward the damping member and to which the connecting member is joined, and a pair of upper and lower energy absorbing parts formed to extend between the protruding tip of the connecting member joint and the upper and lower ends of the vertical member joint, and absorbing energy by buckling deformation in the out-of-plane direction.

[0012] The metal joints are arranged in pairs so as to be located on both sides of the damping member in the front-rear direction.

[0013] The connecting member is joined to the joint portion of the damping member from both sides in the front-rear direction.

[0014] The connecting member is characterized in that it is formed of a steel pipe having a slit into which the joint portion of the damping member is inserted.

[0015] The pair of left and right connecting members and the damping member are joined together to form a unit.

[0016] The vibration control structure for a wooden structure according to the present invention is characterized in that the vibration control damper for a wooden structure is arranged to span in the left-right and right-lateral directions between the upper and lower height-wise mid-portions of a pair of adjacent wooden vertical members of the wooden structure. Effect of the Invention

[0017] The vibration damper for a wooden structure and the vibration-damping structure for a wooden structure according to the present invention can absorb vibration energy efficiently as a whole. [Brief description of the drawings]

[0018] [Figure 1] 1 is a conceptual diagram of a preferred embodiment of a vibration damper for a wooden structure and a vibration control structure for a wooden structure according to the present invention. [Diagram 2] 1 is a front view showing a preferred embodiment of a vibration damper for a wooden structure according to the present invention, the vibration damper being installed between a pair of wooden vertical members. FIG. [Diagram 3] 2. This is a view taken along line AA in FIG. [Figure 4] 4(A) is a front view, FIG. 4(B) is a plan view, FIG. 4(C) is a side view, and FIG. 4(D) is a cross-sectional view taken along line BB in FIG. 4(A). [Diagram 5] FIG. 3 is an exploded view of the vibration damper for a wooden structure shown in FIG. 2. [Figure 6] 6A and 6B are explanatory views for explaining a modified example of the vibration damper for a wooden structure according to the present invention, in which FIG. 6A is a front view and FIG. 6B is a plan view. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Hereinafter, preferred embodiments of the vibration damper for a wooden structure and the vibration control structure for a wooden structure according to the present invention will be described in detail with reference to the accompanying drawings. Fig. 1 shows a conceptual diagram of the vibration damper for a wooden structure according to this embodiment.

[0020] The wooden structure 1 is composed of a plurality of wooden vertical members 2 arranged at appropriate intervals in the left and right lateral directions, and horizontal members, such as wooden horizontal members 3, which are formed long above and below the wooden vertical members 2 in the arrangement direction of the wooden vertical members 2. In the following, the wooden horizontal members 3 will be described as an example of the horizontal members.

[0021] In addition, for the vertical wooden members 2 installed at the outside corners or inside corners, the horizontal members are assembled from the left-right lateral direction and the front-back direction. Furthermore, in the illustrated example, the upper and lower horizontal members are arranged parallel to each other, but there are also cases where the horizontal members are arranged in the left-right lateral direction above the vertical wooden members 2 and in the front-back direction below the vertical wooden members 2, so that the horizontal members are arranged crosswise from top to bottom.

[0022] In this embodiment, the vertical wooden members 2 and the horizontal wooden members 3 are made of rectangular timber with a square cross section, but the shape of the cross section is not important.

[0023] The wooden structure 1 is constructed by joining the upper and lower ends of multiple wooden vertical members 2, which are set upright in the vertical height direction, by butting them against the upper surfaces and lower surfaces of upper wooden horizontal members 3, which are set horizontally to the left and right. The wooden vertical members 2 and the wooden horizontal members 3 can be joined by using various commonly known metal fittings and hardware, and by using a commonly known joining method.

[0024] The wooden vertical members 2 may be columns of a wooden building or vertical members built into a wall. The upper and lower horizontal members exemplified by the wooden horizontal members 3 may be, for example, the foundation itself, or the base, joists laid on the base, and beams of the first floor in the case of the first floor of a wooden building, or beams of the first and second floors in the case of the second floor.

[0025] A vibration damper 4 is incorporated into the wooden structure 1 to provide it with a vibration damping effect. The vibration damper 4 is provided horizontally in the left-right lateral direction between the midpoints in the vertical direction of a pair of adjacent wooden vertical members 2 in the left-right lateral direction of the wooden structure 1 so as to connect these wooden vertical members 2 to each other.

[0026] The vibration damper 4 may be provided at any height position as long as it is located at a midpoint in the vertical height direction of the wooden vertical member 2.

[0027] The vibration damper 4 is joined to each of a pair of wooden vertical members 2 and comprises a pair of left and right connecting metal members 5 spaced apart in the left-right direction, one damping member 6 positioned in the space between the pair of connecting metal members 5 at the center between the pair of wooden vertical members 2, and a pair of left and right connecting members 7 connecting the damping member 6 to the left and right connecting metal members 5, and is configured by arranging the left connecting metal member 5, left connecting member 7, central damping member 6, right connecting member 7, and right connecting metal member 5 in a series in the left-right direction.

[0028] The damping member 6 is positioned so that a constricted portion 8, which will be described later, does not overlap the left and right joint metal members 5. The connecting member 7 has, along its length, one end portion 7a that is overlapped with the damping member 6 in order to join with the damping member 6, and the other end portion 7b that is overlapped with the joint metal member 5 in order to join with the joint metal member 5 (see Figs. 2 and 3).

[0029] In the illustrated example, the vibration damper 4 is provided with two damping members 6 arranged in two upper and lower stages in the vertical height direction of the wooden structure 1, and the connecting members 7 are also provided in two upper and lower stages, and accordingly, the connecting metal members 5 are also provided in two upper and lower stages. The upper and lower stages of the connecting metal members 5 are integrally formed as a continuous unit in the vertical height direction.

[0030] Not limited to the illustrated example, the number of damping members 6, that is, the number of stages, may be any number as long as there is one or more damping members 6, and the joint metal members 5 and the connection members 7 are provided in accordance with the number of damping members 6.

[0031] The vibration damper 4 is shown in detail in Figures 2 to 4. Figure 2 is a front view showing the vibration damper 4 installed between a pair of wooden vertical members 2, Figure 3 is a view taken along line AA in Figure 2, and Figure 4 is an explanatory view explaining the state in which the damping member 6 is joined to the connecting member 7, where Figure 4(A) is a front view, Figure 4(B) is a plan view, Figure 4(C) is a side view, Figure 4(D) is a cross-sectional view taken along line BB in Figure 4(A), and Figure 5 is an exploded assembly view of the vibration damper 4.

[0032] Each damping member 6 is formed of a flat steel plate material of a uniform thickness with flat front and back surfaces. A pair of left and right joints 6a, which are to be joined to the connecting member 7, are formed on both left and right lateral ends of the damping member 6.

[0033] Between these joints 6a, the damping member 6 has a constricted portion 8, which is the main body of the damping member 6. In other words, the damping member 6 is configured to have joints 6a at both left and right lateral end portions and a constricted portion 8 between these joints 6a. The constricted portion 8 of the damping member 6 is formed with an outer contour that is symmetrical about the vertical axis X at the central position (the central position between a pair of wooden vertical members 2) in the length direction of the damping member 6 along the left and right lateral direction of the wooden structure 1.

[0034] That is, the constricted portion 8 is formed at a position equidistant in the left and right lateral directions from the vertical axis X at the center position, and has equal dimensions in the vertical height direction (width dimension).

[0035] The outer contour of the constricted portion 8 is defined by a curve C that extends from each of the joints 6a toward the vertical axis X position at the center in the left-right lateral directions, and is determined by the combined stress of the plastic section modulus and shear stress, which will be described later, in order to set a cross-section at the constricted portion 8 such that the entire cross-section of the constricted portion 8 deforms simultaneously in response to an external horizontal vibration force.

[0036] The damping member 6 is formed such that the constricted portions 8 are smoothly connected to each joint 6a, i.e., connected by an outwardly convex arc-shaped contour so as to have no corners, and the vertical height dimensions of the joints 6a are larger than the vertical height dimensions of the constricted portions 8.

[0037] A pair of connecting members 7 are joined to each of the pair of left and right joints 6a of the damping member 6 from the left and right wooden vertical members 2 sides, respectively.

[0038] Each pair of connecting members 7 has one end 7a connected to the left and right joints 6a of the damping member 6, and the other end 7b joined to a pair of left and right joint metal fittings 5, respectively, thereby connecting the damping member 6 to the left and right joint metal fittings 5.

[0039] In this embodiment, each connecting member 7 is formed of a square steel pipe. At one end 7a of the connecting member 7, a slit 9 for inserting the joint 6a of the damping member 6 is formed in the center of the width direction (front-rear direction of the wooden structure 1) from the edge of the one end 7a in the length direction. The joint 6a of the damping member 6 is fitted into the slit 9 of the connecting member 7 and welded to the connecting member 7, whereby the damping member 6 is joined to the connecting member 7.

[0040] At this time, the upper and lower ends of the joint portion 6a are respectively protruded in the vertical height direction from the connection member 7, and the two are joined by fillet welding W.

[0041] By joining in this manner, the connection member 7 is connected to the damping member 6 with the joint portion 6a sandwiched between the wooden structure 1 from both front and rear sides.

[0042] The pair of left and right connecting members 7 and the damping member 6 joined together may be handled as a unitary component.

[0043] The connecting member 7 may be a plate material such as a steel plate or a shaped steel such as a channel material. In this case, the plate material or shaped steel may be joined in pairs to the joint 6a of the damping member 6 so as to sandwich the plate material or shaped steel from both sides in the front-to-rear direction, or only one may be joined from either side.

[0044] Alternatively, wood may be used as the connecting member 7. In this case, for example, the above-mentioned slit 9 may be formed in the wood, and the joint 6a of the damping member 6 may be inserted therein and the two may be joined with a drift pin. Alternatively, the wood may be overlapped on the joint 6a and the two may be joined with wood screws or nails.

[0045] A pair of left and right joint metals 5 are joined to the other end portions 7b of the pair of left and right connecting members 7. In this embodiment, a pair of joint metals 5 are disposed on both sides of the damping member 6 in the front-rear direction of the wooden structure 1, sandwiching the connecting member 7 from both sides in the front-rear direction. Therefore, a total of four joint metals 5 are provided for one damping member 6, on the left and right sides and the front and rear.

[0046] The joint metal 5 may be disposed on only one side in the front-rear direction. For example, when the connection member 7 is joined to the joint portion 6a of the damping member 6 on only one side in the front-rear direction, only one joint metal 5 is joined to the connection member 7 on the same side.

[0047] Each metal joint 5 is formed using a steel plate material with flat front and back surfaces. A vertical member joint 5a is formed on the edge portion of the metal joint 5 on the side of the wooden vertical member 2 in the vertical height direction of the wooden vertical member 2. The vertical member joint 5a comes into contact with the peripheral side surface of the wooden vertical member 2 when the metal joint 5 is joined to the wooden vertical member 2.

[0048] In the illustrated example (see Figure 3), the front-to-rear dimension of the vibration damper 4 is smaller than the front-to-rear dimension of the wooden vertical member 2. In this case, the vertical member joint 5a is formed by bending the edge portion along the vertical height direction of the joint metal 5 into an L shape so that it fits along the peripheral side surface of the wooden vertical member 2.

[0049] Therefore, the vertical member joint 5a is adapted to come into contact with any of the side surfaces of the wooden vertical member 2 facing in the left-right direction.

[0050] Unlike the illustrated example, when the front-to-rear dimension of the vibration damper 4 is approximately the same as the front-to-rear dimension of the wooden vertical member 2, the vertical member joint 5a abuts against one of the sides of the wooden vertical member 2 facing the front-to-rear direction, without bending the end edge portion of the joint metal 5, remaining flat.

[0051] The metal joint 5 is joined to the wooden vertical member 2 by screwing a screw 10 into the wooden vertical member 2 through a screw hole formed in the vertical member joint 5a.

[0052] The metal joint 5 is formed with a connection member joint 5b that protrudes from the vertical member joint 5a toward the damping member 6 and to which the other end 7b of the connection member 7 is joined.

[0053] The connecting member joint portion 5b abuts against the front or rear surface of the other end portion 7b of the connecting member 7, and the abutting area is defined as the connecting member joint portion 5b for the connecting member 7.

[0054] In other words, the connection member joint 5b is defined by the dimensions, shape, etc. of the other end 7b of the connection member 7 that is in contact with and joined from the protruding tip 5c, which is the tip in the protruding direction, to the wooden vertical member 2 side.

[0055] Unlike the vertical member joint 5a which may be formed by bending, the connecting member joint 5b is formed by the plate surface of the connecting metal 5 itself, and this plate surface is overlapped and abutted against the other end 7b of the connecting member 7.

[0056] In the illustrated example, the connecting member 7 is joined to the metal joint 5 with the other end 7b being spaced from the wooden vertical member 2.

[0057] The joint metal 5 and the connection member 7 are joined by mounting fasteners 11 such as screws that can be freely aligned to absorb dimensional errors and assembly errors between the wooden vertical members 2 and the wooden horizontal members 3, as well as dimensional errors of the components from the damping member 6 to the wooden vertical members 2.

[0058] In addition, by attaching and detaching the mounting connector 11, the unitized damping member 6 and the pair of connecting members 7 can be easily replaced at any time for the joint metal 5.

[0059] Each joint metal 5 is arranged between the vertical member joint 5a and the connecting member joint 5b, i.e., in a direction in which the connecting member 7 abuts against the wooden vertical member 2, so that a pair of upper and lower energy absorption sections 12 are formed by the joint metal 5 itself at a pair of upper and lower corner sections partitioned by the wooden vertical members 2 above and below the connecting member 7.

[0060] Looking at any one of the upper and lower two-tiered damping members 6, there are four corner portions in total, top and bottom, on both the left and right lateral sides of the damping member 6, and upper and lower energy absorption portions 12 are formed at these corner portions by four connecting metal members 5.

[0061] These energy absorbing parts 12 are buckled and deformed in the out-of-plane direction by the compressive load when a horizontal external vibration force that knocks down the wooden vertical members 2 acts on the wooden structure 1, causing deformation, and absorb energy in a hysteretic manner due to the repetition of this buckling deformation.

[0062] When viewed above the upper damping member 6, the energy absorbing portion 12 is configured to have a protruding edge portion 5d at the corner portion that extends from at least the protruding tip 5c side of the connecting member joint 5b toward the upper end side of the vertical member joint 5a.

[0063] In detail, this energy absorbing portion 12 protrudes upward from the connecting member joint 5b and laterally from the vertical member joint 5a, and this protruding shape is defined by a protruding edge 5e which starts from the upper end side of the vertical member joint 5a and rises laterally in a predetermined left-right lateral dimension in parallel to the connecting member joint 5b, and the above-mentioned protruding edge 5d which extends from the end of this protruding edge 5e toward the protruding tip 5c of the connecting member joint 5b.

[0064] In the illustrated example, the protruding edge 5d is composed of an inclined portion 5f which gradually moves away from the vertical member joint 5a as it moves from the upper end side of the vertical member joint 5a toward the connecting member joint 5b downward in the vertical height direction, and a curved portion 5g which is continuous with this inclined portion 5f and converges toward the upper edge of the connecting member joint 5b.

[0065] Further, the protruding edge portion 5d is at least partially formed with a bent portion 5h for stiffening the energy absorbing portion.

[0066] The bent portion 5h bears the stress generated along the protruding edge portion 5d when the energy absorbing portion 12 buckles and deforms, thereby preventing localized breakage and early destruction of the energy absorbing portion 12. The bent portion 5h can also resist torsional deformation generated in the metal joint 5.

[0067] The energy absorbing portion 12 formed below the lower damping member 6 is configured in a similar manner.

[0068] The vibration damper 4 of this embodiment integrates the upper and lower two tiers of damping members 6, i.e., the connecting metal 5 is configured by integrating the lower energy absorbing portion 12 for the upper tier damping member 6 and the upper energy absorbing portion 12 for the lower tier damping member 6 into a single piece so as to join the upper and lower tiers of damping members 6 to the wooden vertical member 2 as a whole, and the protruding edge portions 5d of the lower energy absorbing portion 12 for the upper tier and the upper energy absorbing portion 12 for the lower tier are connected in a straight line in the vertical height direction via a quarter-circular curved portion.

[0069] When there is one damping member 6, the energy absorbing portion 12 defined by the protruding edge 5d having the above-mentioned protruding edge 5e and inclined portion 5f is formed at each of the upper and lower corner portions of the connection member joint portion 5b.

[0070] The yield strength of the connecting metal 5 and the connecting member 7 described above are each set to be greater than the yield strength of the constricted portion 8 of the damping member 6. Therefore, unless the external vibration force is extremely large, energy absorption is performed at the constricted portion 8, and in such cases, energy absorption is performed including by the connecting metal 5.

[0071] In this embodiment, the outer contour of the necked portion 8, which is symmetrical with respect to the above-mentioned vertical axis X, is determined by the combined stress of the plastic section modulus and the shear stress.

[0072] When an external vibration force is applied to the damping member 6 from the horizontal direction and a shear force is generated in the constricted portion 8, bending stress and shear stress are generated in the constricted portion 8.

[0073] Taking this into consideration, in order to efficiently absorb energy, it is desirable to form the constricted portion 8 in a shape that is suited to this stress state.

[0074] The load at which deformation due to bending stress begins is determined by P = σ · Zp / L (1). P: Load σ: Yield stress Zp: Plastic section modulus (b h 2 / 4; b: plate thickness, h: vertical height dimension (width dimension) L: Horizontal distance from the center of the constriction (vertical axis)

[0075] The load at which deformation due to shear stress begins is determined by P = τ·A(2). τ: Yield shear stress A: Cross-sectional area of ​​the neck (b h)

[0076] If no bending moment occurs, the only stress occurring in the constricted portion 8 is shear stress. Based on equation (2), the shear stress τ can be calculated from the cross-sectional area (τ=P / A). In that case, the cross-sectional area of ​​the constricted portion 8 may be constant.

[0077] If no shear force is generated, the only stress generated in the necked portion 8 will be bending stress. Based on formula (1), the bending stress σ can be calculated from the plastic section modulus according to the lateral distance L from the necked portion 8. In that case, the cross-sectional area is zero at the center of the necked portion 8 (vertical axis X), and as the distance L increases, the required cross-sectional area also increases.

[0078] Since the thickness of the constricted portion 8 (damping member 6) is constant, the vertical height dimension is large. In reality, a cross section connecting the left and right sides is required at the vertical axis X position for structural reasons.

[0079] From the above discussion, taking into consideration that bending moment and shear force occur simultaneously in reality, the combined stress of the plastic section modulus and shear stress is expressed as the von Mises yield condition σvm(σvm=√(σ 2 +3τ 2 ) is used to find the values ​​for all cross sections of the constricted portion 8 in the left and right lateral directions, and the curve C of the constricted portion 8 is determined.

[0080] As a result, when an external vibration force acts on the constricted portion 8, the entire cross section of the constricted portion 8 is deformed simultaneously to absorb the vibration energy.

[0081] Next, the operation of the vibration damper for a wooden structure and the vibration damping structure for a wooden structure according to this embodiment will be described.

[0082] As shown in FIG. 5, the vibration damper 4 is fabricated by joining one end 7a of a connection member 7 to each joint 6a of the damping member 6, thereby producing a unitized part.

[0083] On the other hand, a pair of left and right joint metals 5 are joined to each of a pair of adjacent wooden vertical members 2 via vertical member joints 5a.

[0084] Finally, the left and right connection members 7 are joined to the left and right joint metal members 5, respectively, via the connection member joint portions 5b.

[0085] As a result, the vibration dampers 4 are installed horizontally in the left and right lateral directions between the wooden vertical members 2 of the wooden structure 1, and a vibration-damping structure for the wooden structure 1 is constructed.

[0086] When a horizontal vibration external force such as an earthquake acts, if the external force is not extremely large, deformation stress is generated in a concentrated manner in the neck portion 8 of the damping member 6 through the joint metal 5 and the connection member 7.

[0087] The outer contour of the constricted portion 8 is defined by curve C, which is determined by the combined stress of the plastic section modulus and shear stress, and the bending stress and shear stress cause deformation simultaneously across the entire cross section, thereby making use of the entire material and enabling vibration energy to be absorbed efficiently and effectively.

[0088] On the other hand, when the external force is extremely large, the connecting metal 5 has a greater yield strength than the constricted portion 8, so that the vibration energy can be absorbed by the energy absorption portion 12 of the connecting metal 5, thereby preventing the constricted portion 8 from being severely deformed and damaged.

[0089] In other words, in the vibration damper and vibration control structure of this embodiment, when the external vibration force is large, the connecting metal 5 and damping member 6 absorb the vibration energy, and when the external vibration force is small, the damping member 6 absorbs the vibration energy by switching depending on the magnitude of the external vibration force, thereby enabling effective vibration control, and the narrowed portion 8 provided in the damping member 6 ensures sufficient vibration control function.

[0090] Since curve C of constricted portion 8 is determined by the Mises yield criterion, constricted portion 8 can be formed in an appropriate shape according to the stress state, and its entire cross section can be deformed simultaneously to efficiently absorb vibration energy.

[0091] The damping member 6 is joined to the metal joint 5 via the connecting member 7, so that the metal joint 5 can reliably prevent the damping member 6 from being deformed out of plane.

[0092] The vibration control damper 4 can be installed at any suitable position in the vertical direction of the wooden vertical member 2, so that it can be installed avoiding piping and openings, ensuring a high degree of freedom in design and construction.

[0093] Since the vertical height dimension of the joint 6a of the damping member 6 is set to be larger than the vertical height dimension of the constricted portion 8, the constricted portion 8 can stably exert its vibration damping performance regardless of the dimensions, shape, etc. of the connecting member 7.

[0094] Since the yield strength of the constricted portion 8 is smaller than the yield strength of the connecting member 7 and the connecting metal 5, the constricted portion 8 can reliably absorb vibration energy for an external vibration force that is not extremely large, and for an external vibration force that is extremely large, the load on the constricted portion 8 is reduced so that the constricted portion 8 is not damaged, and the connecting metal 5 can reliably absorb the vibration energy.

[0095] Since the metal joint 5 is provided with the energy absorbing portion 12 in addition to the joints 5a, 5b with the wooden vertical member 2 and the connecting member 7, the energy absorbing portion 12 can appropriately absorb vibration energy.

[0096] The connecting metal members 5 are arranged in pairs so as to be located on both the front-to-rear sides of the damping member 6, so that the connecting metal members 5 can resist torsional forces and can appropriately apply horizontal external forces to the narrowed portions 8 of the damping member 6 to damp vibrations.

[0097] Since the connecting member 7 is joined to the joint 6a of the damping member 6 from both the front-to-rear direction sides, it firmly holds the joint 6a and can properly transmit external vibration forces to the constricted portion 8 while suppressing out-of-plane deformation of the damping member 6.

[0098] Since the connecting member 7 is a steel pipe having a slit 9 formed therein into which the joint portion 6a of the damping member 6 is inserted, out-of-plane deformation of the damping member 6 can be suppressed and the two can be joined easily and reliably.

[0099] The pair of left and right connecting members 7 and the damping member 6 are joined together to form a unit that can be handled as one component, making on-site assembly work more efficient and easier.

[0100] The vibration control structure of the wooden structure in this embodiment is equipped with the above-mentioned vibration control damper 4, which can reliably and efficiently absorb the energy of external vibration forces, thereby providing excellent vibration control performance.

[0101] A modification of the above embodiment is shown in Fig. 6. In this modification, the slit 9 is formed in one end 7a of a pair of left and right connecting members 7 so as to be much longer than the joint 6a of the damping member 6, and the joint 6a is joined to the back side of the slit 9. As a result, the connecting members 7 are assembled to the damping members 6 so that only the vicinity of the vertical axis X of the constricted portion 8 appears between the connecting members 7.

[0102] With this configuration, it is possible to protect the constricted portion 8 by surrounding it with the connecting member 7. Needless to say, even with this modified example, the same effects as those of the above embodiment can be achieved. [Explanation of symbols]

[0103] 1 Wooden structure 2 Wooden vertical members 3 Wooden cross members 4. Vibration damper 5. Joint metal fittings 5a Longitudinal joint 5b Connection member joint 5c Protruding tip of connecting member joint 6 Damping material 6a Joint 7 Connection parts 7a One end 7b Other end 8. Waist 9 Slit 12 Energy absorption section C Curve of the outer contour of the constricted part

Claims

1. A vibration damper is provided in a wooden structure formed by joining upper and lower ends of a plurality of wooden vertical members to upper and lower horizontal members, the vibration damper being provided in a horizontal direction between upper and lower mid-way portions of a pair of wooden vertical members adjacent in the horizontal direction, the vibration damper comprising: A pair of left and right joint metals are joined to each of the pair of wooden vertical members and spaced apart from each other in the left and right lateral directions; A damping member disposed between the metal joints and having a pair of joints at both left and right lateral ends; a pair of left and right connecting members, one end of which is joined to each joint of the damping member and the other end of which is joined to each of the pair of joint metals, for connecting each joint of the damping member to each of the joint metals, The above-mentioned damping member is formed from a flat steel plate and has joints at both left and right lateral ends and a main body between these joints, and the outer contour of the main body from each of the joints toward the center in the left and right lateral directions is defined by a curve determined by the combined stress of the plastic section modulus and shear stress.

2. 2. The vibration damper for wooden structures according to claim 1, wherein the vertical dimension of each joint of the damping member is greater than the vertical dimension of the main body.

3. 3. The vibration damper for wooden structures according to claim 1, wherein the yield strength of the main body of the damping member is smaller than the yield strength of each of the connecting member and the metal joint.

4. The vibration damper for wooden structures described in any one of claims 1 to 3, characterized in that the connecting metal is a steel plate-like material having: a vertical member joint formed in the vertical height direction of the wooden vertical member and joined to the wooden vertical member; a connecting member joint protruding from the vertical member joint toward the damping member and to which the connecting member is joined; and a pair of upper and lower energy absorption parts formed to extend between the protruding tip of the connecting member joint and the upper and lower ends of the vertical member joint, absorbing energy by buckling deformation in the out-of-plane direction.

5. The vibration damper for wooden structures according to any one of claims 1 to 4, characterized in that a pair of said metal joints are arranged so as to be located on both sides of said damping member in the front-rear direction.

6. 6. The vibration damper for wooden structures according to claim 1, wherein the connecting members are joined to the joints of the damping members from both front and rear sides.

7. 7. The vibration damper for wooden structures according to claim 1, wherein the connecting member is formed of a steel pipe having a slit into which the joint of the damping member is inserted.

8. The vibration damper for wooden structures according to any one of claims 1 to 7, characterized in that the pair of left and right connecting members and the damping member are joined together to form a unit.

9. A vibration-damping structure for a wooden structure, characterized in that the vibration-damping damper for a wooden structure according to any one of claims 1 to 8 is arranged to span in the left-right and right-lateral directions between the vertical and vertical height-wise mid-points of a pair of adjacent wooden vertical members of the wooden structure.

10. A method for producing the vibration damper for a wooden structure according to any one of claims 1 to 8, comprising the steps of: determining values ​​of the von Mises yield criterion for all lateral cross sections of the body and determining the curves defining the outer contour of the body based on these values.

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