JP5339406B2 - Seismic structure - Google Patents

Abstract

This aims to improve the earthquake resistance of a mainly shear-deformable structure such as a high-rise building. Provided is an earthquake-proof structure having an upper structure supported on a lower structure and resisting a main vertical load and a horizontal load mainly with a framed structure. The upper structure is made of an integral cantilever shearing structure including a fixed end floor portion having a plurality of floors, of which the lowermost floor to become the fixed end side is fixed on the lower structure, a folded portion forming floor for forming the upper floor of the fixed end floor portion, and a free end floor portion composed of a plurality of floors to the upper floor formed by the folded portion forming floor and supporting the lowermost floor to become the free end side horizontally movably on the lower structure. As compared with the shearing structure of the prior art having the fixed lower end, therefore, the folded cantilever shearing structure has twice dynamic orders in connection with an nature period, as large as the orders in the height direction. The nature period of the shearing structure increases in proportion to the orders, so that the nature period of the folded cantilever shearing structure is about two times as long as that of the shearing structure of the prior art.

Description

  The present invention relates to an earthquake-resistant structure capable of improving the earthquake-resistant performance of a structure mainly composed of shear deformation such as a high-rise building.

  The magnitude of the seismic force acting on the structure due to the ground motion is related to the period / amplitude characteristics of the ground motion and the vibration characteristics such as the natural period and damping constant of the structure. Appropriate design of the natural period and damping constant is considered important for economical seismic design (see, for example, Non-Patent Document 1).

  In Non-Patent Document 1, the design ground motion used for checking the seismic performance of a structure is defined by a standard acceleration response spectrum, a correction coefficient for each attenuation constant, and a correction coefficient for each region. According to the standard acceleration response spectrum of Level 1 and Level 2 ground motions of Non-Patent Document 1, in the natural period exceeding about 1 second, the acceleration is reduced according to the longer natural period.

  Non-Patent Document 2 stipulates that the seismic force is calculated by multiplying the sum of the fixed load and the loaded load by the seismic layer shear force coefficient. If the seismic layer shear force coefficient is arranged as a function of the natural period, the seismic layer shear force coefficient is reduced in response to the longer natural period in the natural period exceeding about 1 second.

Increasing the natural period reduces the seismic force acting on the structure, while causing an increase in displacement amplitude due to a decrease in the rigidity in the horizontal direction. A structure in which a long period and high damping are positively incorporated into an earthquake-resistant design has been put into practical use as a base-isolated building using an isolator and a damper (see Non-Patent Document 3).
Japan Highway Bridge Association: Road Bridge Specification / Explanation V Seismic Design, pp. 12-29, March 2002 Building Standard Act Construction Order: 1958 Decree No. 338: Building Standard Act Enforcement Order, Article 88, Final Revision November 7, 2005 Decree No. 334 Architectural Institute of Japan: Seismic isolation design guidelines, pp. 26-56, September 20, 1989

  Isolation buildings using isolators and dampers are generally expensive, and their scope of application is limited to low-rise buildings such as medical facilities and public facilities that require high earthquake resistance, and can be applied to general high-rise buildings. An inexpensive earthquake-resistant structure is required.

In addition, a long period in the region where the natural period exceeds 1 second is expected to be caused by a huge trench-type earthquake, and is likely to cause resonance with a long-period ground motion. The importance of effective seismic control is increasing (see Non-Patent Document 4).
Civil engineering company, Architectural Institute of Japan: Joint proposal on long-period ground motions caused by huge subduction earthquakes and improvement of earthquake resistance of civil engineering and building structures, November 20, 2006

  Therefore, in the present invention, a shear structure having a natural vibration mode having a longer period than that of a conventional shear structure for the purpose of improving the seismic performance of a structure mainly composed of shear deformation such as a high-rise building. And the arrangement | positioning structure of the efficient damping device applied to the structure is provided.

  Here, the conventional shearing structure is a cantilevered shearing structure consisting of a plurality of layers with the lowermost floor as the fixed end fixed to the lower structure and the uppermost floor as the free end. By using a vibration model in which the restoring force is represented by a shear spring, the natural period and natural vibration mode of the structure necessary for seismic design can be calculated with sufficient engineering accuracy.

The earthquake-resistant structure of the present invention according to claim 1 supports the upper structure on the lower structure, and the upper structure is a structure that mainly resists vertical and horizontal loads mainly in a frame structure. The upper structure is composed of a fixed end side layer portion composed of a plurality of layers in which the lowermost floor on the fixed end side is fixed to the lower structure, and a bent portion forming layer forming the uppermost floor of the fixed end side layer portion. And the bent portion forming layer forms the uppermost floor, and the lowermost floor, which is the free end side, is supported by the lower structure so that it can be moved horizontally using a horizontally movable support device. An integral folded cantilever shear structure that is bent upwardly from the layer portion, and at least a pair of bent cantilever shear structures is formed with the fixed end layer portion outward and the free end layer With the part positioned inward and the free end Characterized in that none To integrally hierarchical portions.

  Here, the bending part formation hierarchy comprises at least the beam part provided in the upper floor of the fixed end side hierarchical part and the beam part provided in the upper floor of the free end side hierarchical part in common.

The seismic structure of the present invention according to claim 2 is the seismic structure according to claim 1, wherein the bent cantilever shear structures are arranged radially, and the fixed end side adjacent in the circumferential direction is provided. The present invention is characterized in that the layer portions are integrally connected to form a cylindrical shape surrounding the free end side layer portion .

The earthquake-resistant structure of the present invention according to claim 3 is the earthquake-resistant structure according to claim 1 or 2 , wherein an attenuation device is interposed between the lowermost floor and the lower structure of the free end side layer. It is characterized by that.

The earthquake-resistant structure of the present invention according to claim 4 is the earthquake-resistant structure according to any one of claims 1 to 3 , wherein the fixed end side layer portion and the free end side layer portion are opposed to each other. Among them, an attenuation device is interposed between at least one pair of opposing layers or between opposing cantilever portions (or cantilever floor portions), and the fixed end side layer portion and the free end are provided by the attenuation device. The side layer portions are connected in the horizontal direction.

The earthquake-resistant structure of the present invention according to claim 5 is the earthquake-resistant structure according to any one of claims 1 to 4 , wherein the fixed end layer portion and the free end layer portion are opposed to each other. Of these, at least one pair of opposing cantilever portions (or cantilever floor portions) is extended by extending cantilever portions (or cantilever floor portions) from the beam portions (or floor portions) of the opposite levels. The floor expansion / contraction device is interposed between the fixed end side layer portion and the free end side layer portion so as to be horizontally expandable / contractible. To do.

The earthquake-resistant structure of the present invention according to claim 6 is the earthquake-resistant structure according to any one of claims 1 to 5 , wherein the side surfaces of the fixed end side layer portion and the free end side layer portion facing each other. Stretch the base frame that attaches the outer wall or the side outer wall in the horizontal direction, and expand and contract the outer wall between the facing side outer wall parts, between the facing base frame parts, or between the facing side outer wall part and the base frame part. The apparatus is characterized in that a gap for absorbing horizontal relative displacement between the fixed end side layer portion and the free end side layer portion is closed in a horizontal direction so as to be expandable and contractable by the outer wall expansion / contraction device.

  The present invention realizes a longer natural period in the horizontal direction of the shear structure by reviewing the conventional support structure of the shear structure and the arrangement of the frames constituting the shear structure, and is based on the damping device. This realizes the expression of the natural vibration mode having a shape that is advantageous for increasing damping.

(1) In the present invention described in claim 1, the upper structure is supported on the lower structure, and the upper structure is a structure that is mainly a frame structure and resists vertical and horizontal loads. The structure is composed of a plurality of layers in which the lowermost floor on the fixed end side is fixed to the lower structure, a fixed end side layered portion, a bent portion forming layer forming the uppermost floor of the fixed end side layered portion, and The bent portion forming layer forms the uppermost floor, and the lower end floor which is the free end side is supported by a lower structure in a freely movable manner using a horizontal movable support device. And an integral bent cantilever shear structure bent upwardly in a projecting manner , and at least a pair of bent cantilever shear structures are formed with the fixed end side layer portion outward and the free end side layer portion Arranged so as to be located inward and free end side layer Forms To integrally with each other.

The seismic structure according to the present invention configured as described above and formed into a bent cantilevered shear structure that is bent upwardly in a projecting manner is such that the upper end of the conventional shear structure, that is, the free end faces the ground. This corresponds to a structure in which the structure is bent at approximately a half point in the height direction and the free end can be moved horizontally. Therefore, as compared with a conventional shear structure with a fixed lower end, the mechanical rank related to the natural period of the bent cantilever shear structure of the present invention is about twice the rank in the height direction. Since the natural period of the shearing structure increases in proportion to the rank, the natural period of the bent cantilever shear structure of the present invention, you about twice the length period of the natural period of the conventional shearing structure .

  In addition, the folded cantilever shear structure of the present invention exhibits a natural vibration mode characterized by a large horizontal relative displacement between the opposed layers of the fixed end side layer portion and the free end side layer portion. In the primary natural vibration mode that is most important for seismic design, the horizontal relative displacement is gradually increased from the upper floor to the lower floor, and is maximized at the lower floor. The primary natural vibration mode is a natural vibration mode having the longest natural period.

  In general, in order to efficiently increase the damping of the structure, it is preferable to apply a Coulomb friction force, a viscous force, or the like to a site where a large relative displacement occurs. Since the lowermost floor of the free end side layer is supported by the lower structure so that it can move horizontally, the Coulomb friction force proportional to the product of the dynamic friction coefficient of that location and the vertical reaction force of the free end side layer during horizontal movement Occurs between the lowest floor of the free end side layer and the lower structure. Since the Coulomb friction force caused by the vertical reaction force acts on the portion where the horizontal relative displacement in the primary natural vibration mode is the largest, the folded cantilever shear structure of the present invention potentially has a large friction damping. In the conventional shear structure, the Coulomb friction force caused by such a vertical reaction force is not generated.

  Therefore, in the present invention described in claim 1, since it can be a shear structure having a natural vibration mode having a long period as compared with a conventional shear structure, the structure is obtained by increasing the natural period. It is possible to reduce the acting seismic force, and because it has a large friction damping due to the Coulomb friction force generated at the lowest floor of the free end side layer, Since it is possible to reduce the vibration amplitude, it is possible to improve the seismic performance of a structure that mainly undergoes shear deformation such as a high-rise building.

(2) In the present invention described in claim 2, the bent cantilever shear structures are arranged radially, and the fixed end side layer portions adjacent to each other in the circumferential direction are integrally connected to each other to form a free end layer. It has a cylindrical shape surrounding the part .

Even in such a configuration, it is possible to provide an earthquake-resistant structure having a long period and a high attenuation.

( 3 ) In the present invention described in claim 3 , an attenuation device is interposed between the lowermost floor of the free end side layer and the lower structure.

  The vibrational energy consumed by the Coulomb friction generated between the lowermost floor and the lower structure of the free end side layer portion increases and decreases in proportion to the horizontal relative amplitude of the lowermost floor and the lower structure. On the other hand, the vibration energy of the structure increases or decreases in proportion to the square of the horizontal relative amplitude of the relevant part. Accordingly, when the horizontal relative amplitude of the portion increases, that is, when the vibration amplitude of the shear structure increases, the effect of friction damping by the Coulomb friction force decreases.

  As a method for compensating for a decrease in the effect of frictional damping accompanying an increase in vibration amplitude, for example, it is conceivable to install a viscous damping device that consumes vibration energy in proportion to the square of the amplitude. In order to maximize the capability of the viscous damping device, it is necessary to attach the viscous damping device to a portion where the relative speed is maximized. The part where the relative velocity is maximum coincides with the part where the relative displacement is maximum.

  In the bent cantilever shear structure of the present invention, the horizontal relative displacement in the primary natural vibration mode, which is the most important for seismic design, is maximized on the lowest floor of the free end side layer. Therefore, it is possible to improve the damping performance of the shear structure most efficiently by interposing the damping device between the lowermost floor of the free end side layer and the lower structure.

( 4 ) In the present invention described in claim 4 , at least one pair of opposing hierarchies or opposing cantilever portions (or maybe) among the opposing hierarchies of the fixed end side hierarchies and the free end side hierarchies. An attenuation device is interposed between the cantilever floor portions), and the fixed end side layer portion and the free end side layer portion are connected in the horizontal direction by the attenuation device.

  Here, the bent cantilever shear structure of the present invention exhibits a natural vibration mode characterized by a large horizontal relative displacement between the opposing layers of the fixed end side layer portion and the free end side layer portion. This horizontal relative displacement gradually increases from the upper floor to the lower floor in the primary natural vibration mode and becomes the maximum in the lowermost floor of the free end side layer, but in the secondary and subsequent natural vibration modes, the upper floor Between the lower floor and the middle floor, near the upper floor, or near the lower floor.

  On the other hand, in a high-rise building with a large number of floors, the natural period becomes longer in proportion to the increase in floors, so controlling vibrations in the second and subsequent natural vibration modes in addition to the primary natural vibration mode is earthquake resistant. May be important in design.

  In order to increase the damping most efficiently for the secondary and subsequent natural vibration modes in addition to the primary natural vibration mode, in the natural vibration mode of the order of the attenuation increase target, the fixed end side layer portion and the free end What is necessary is just to connect between the hierarchy where horizontal relative displacement between the hierarchies which a side hierarchy part opposes becomes the horizontal direction with an attenuation device.

  Accordingly, the damping device interposing method of the present invention can maximize the performance of the damping device, and effectively reduces the damping performance of the shear structure for the natural vibration modes of the second and subsequent orders in addition to the primary. It is possible to improve.

  It is to be noted that the damping device according to claims 6 and 7 includes a viscous damping device that utilizes the viscous resistance of fluid, an oil damper that utilizes pressure drop due to fluid turbulence, a hysteretic damper that utilizes plastic deformation of metal, and coulomb. It is a device that can consume vibration energy, such as a frictional damping device that uses friction. In addition, using a variable oil damper that can control the damping coefficient using magnetic fluid in real time, the damping performance of the shear structure is changed by changing the damping coefficient of the variable oil damper according to the magnitude of the vibration amplitude. It is also possible to incorporate a method for controlling in real time.

( 5 ) According to the invention described in claim 5 , at least one set of the beam portions (or floor portions) facing each other from the facing layers of the fixed-end-side layer portion and the free-end-side layer portion is separated from each other. Extending the cantilever part (or cantilevered floor part), interposing a floor expansion / contraction device between the opposing cantilever parts (or cantilevered floor part), and using the same floor expansion / contraction device, the fixed end side layer The gap for absorbing the horizontal relative displacement between the portion and the free end side layer portion is closed so as to be extendable in the horizontal direction.

  The purpose of constructing a high-rise building that is the subject of the present invention is to provide a safe, comfortable and inexpensive living space and storage space. Therefore, securing the living space and the storage space to the maximum in the limited space is important in providing an inexpensive space.

  In the shear structure of the present invention, a floor for use in a living space and a storage space is installed in the space between the fixed end side layer portion and the free end side layer portion. In order to install this floor portion, the cantilever portion is extended from the beam portion of the fixed end side layer portion and the free end side layer portion, and the cantilever floor portion is configured using the cantilever portion. did. However, since a horizontal relative displacement occurs in the fixed end side layer portion and the free end side layer portion facing each other, a gap for absorbing the horizontal relative displacement is provided in the opposite cantilever portion and the cantilever floor portion. It was. Further, since the same gap in the cantilever floor is not suitable for safety management, the cantilever floor can be used as a living space and a storage space by closing the gap with a floor expansion device that easily deforms the gap.

  In addition, the restoring force of the floor expansion and contraction device generated by the horizontal relative displacement of the fixed end side layer portion and the free end side layer portion facing each other is assumed to be small enough not to affect the natural period of the shear structure.

  It should be noted that the cantilever floor is reinforced with a floor beam or the like at the middle or end of the cantilever floor as required. Moreover, when the frictional force etc. which generate | occur | produce with the expansion-contraction apparatus for floors are constant and quantitative over time, you may consider the frictional force as a frictional damping of a shearing structure.

( 6 ) In the invention described in claim 6 , the opposing side surface outer wall portion of the fixed end side layer portion and the free end side layer portion or the base frame portion to which the side surface outer wall is attached is extended in the horizontal direction to oppose the side surface outer wall portion. Between the opposing frame parts between each other, or between the opposing lateral outer wall part and the underlying frame part, an expansion device for the outer wall is interposed, and the fixed end side layer part and the free end side by the expansion device for the outer wall The gap that absorbs the horizontal relative displacement of the layer portion is closed in such a manner that it can expand and contract in the horizontal direction.

  The purpose of constructing a high-rise building that is the subject of the present invention is to provide a safe, comfortable and inexpensive living space and storage space. Therefore, it is important to provide a safe and comfortable space.

  In the shear structure of the present invention, since horizontal relative displacement occurs in the fixed end side layer portion and the free end side layer portion, at the boundary between the fixed end side layer portion and the free end side layer portion facing each other, each layer portion A gap for absorbing the same horizontal relative displacement is provided between the end portions of the side outer wall installed on the side. Since this gap is not suitable for the purpose of providing a comfortable space because it causes intrusion of wind and rain, it was decided to close the gap with an expansion device for an outer wall that easily deforms.

  In order to minimize the size of the gap and to attach the expansion device for the outer wall, the base frame that attaches the side outer wall or the side outer wall of the fixed end layer and the free end layer is stretched in the horizontal direction, and the side outer wall It was decided to close the gap between the ends of the outer wall with an expansion device for an outer wall that easily deforms. Here, the foundation frame is generally called a stud or a trunk edge that is installed to attach an outer wall or the like.

  In addition, the restoring force of the outer wall expansion / contraction device generated by the horizontal relative displacement of the fixed end side layer portion and the free end side layer portion facing each other is assumed to be small enough not to affect the natural period of the shear structure. When vibration energy consumption caused by plastic deformation of the external wall expansion and contraction device generated by the horizontal relative displacement is constant and quantitative over time, the vibration energy consumption can be considered as attenuation of the shear structure. good.

  In this embodiment, first, the characteristics of the support structure based on the framework and the substructure of the shear structure according to the present invention are described, the equation of motion of the shear structure and the eigenvalue problem of the non-damped system are formulated, and the natural vibration Elucidate the natural period and shape of the mode and the damping constant theoretically. Next, the efficient arrangement of the viscous damping device focusing on the shape of the natural vibration mode obtained by the vibration theory is described, and the increase in the damping constant due to the installation of the viscous damping device is clarified theoretically. The natural period, shape and damping constant of the natural vibration mode obtained by the vibration theory are specifically verified by vibration experiments using a reduced model. Finally, the characteristics of the shear structure according to the present invention, which are clarified by vibration theory and vibration experiment, are summarized.

  [Vibration theory of a bending shear structure according to the present invention]

(1) Conventional Cantilever Shear Structure FIG. 1 shows a shear structure in which the lower end, which is one of the plane vibration models of a high-rise building, is fixed to the base. This vibration model is composed of n beams, two pillars of equal cross section rigidly connected to them, and n dashpots, and forms an n-layer shear vibrator with the same dynamic characteristics of each layer. This vibration model is referred to as System-CS.

The height of each layer is h, and the height of the structure is h _total = nh. Therefore, n representing the number of layers also serves as a parameter representing the geometric height of the structure. Columns are elastic and beams are rigid. The mass of the columns and beams is concentrated on the beams in each layer. The symbols k, m, and c in FIG. 1 are the shear spring constant and mass of each layer and the viscous damping coefficient of the dashpot. The dashpot represents the structural attenuation of the structure or the attenuation by the viscous damping device that connects the conventional upper and lower beams (hereinafter abbreviated as a vertical plane arrangement). The horizontal displacement of the beam when the base portion causes the horizontal displacement z (t) is defined as x ₁ , x ₂ ,..., X _n as shown in FIG. Here, t represents time. FIG. 1 is an image at the time of deformation, and the column before the deformation is straight.

本実施形態では、Ｔ_０、ω_０およびζ_０をそれぞれ層固有周期、層固有円振動数、および層粘性減衰定数と呼ぶ。FIG. 2 shows a vibration model that defines the dynamic characteristics of each layer of System-CS as a cantilever shear structure. When the horizontal displacement of the beam when the horizontal force p _h acts on the beam as in FIG. And x, for the shear spring constant k is assumed that there is relationship between p _{h =} kx. When the mass is concentrated on the beam, the vibration system becomes a one-degree-of-freedom vibration model including a shear spring constant k, a viscous damping coefficient c, and a mass m. Therefore, the natural circular frequency ω ₀ , natural period T _0, and viscous damping constant ζ ₀ of the non-damped system of this vibration model are expressed by the following equations, respectively.

In the present embodiment, T ₀ , ω ₀ and ζ ₀ are referred to as a layer natural period, a layer natural circular frequency, and a layer viscous damping constant, respectively.

The equation of motion when the base produces a horizontal displacement z (t) in System-CS is expressed by the following equation.

ルとする。

Let's say.

  A vector superscript / bracketed subscript (n) indicates that the size of the vector or square matrix is n. The superscript T indicates the transpose of the matrix.

In Equation 2, K ⁽ⁿ⁾ , C ^(n), and M ⁽ⁿ⁾ are a stiffness matrix, an attenuation matrix, and a mass matrix, respectively, represented by the following equations.

Here, I ⁽ⁿ⁾ is a unit matrix, and A ⁽ⁿ⁾ is a tridiagonal matrix of the following equation.

The eigenvalue problem of the non-attenuating system of System-CS is as follows.

Here, ω and ψ ⁽ⁿ⁾ are the natural circular frequencies and the corresponding eigenvectors. Using the number (4a) and the number (4c), the number (6) is transformed into the standard eigenvalue problem of the following equation.

Here, λ is an eigenvalue. The ratio between the natural circular frequency ω _i and the layer natural circular frequency ω ₀ , the ratio between the natural period T _i and the layer natural period T ₀ , and the natural _value λ _i have the following relationship.

する。

To do.

From Equations 8 and 9, the ratio between the natural period T _i and the layer natural period T ₀ is expressed by the following equation.

Number 12 from cantilever shear structure, the natural period of the System-CS is determined by the layer specific period T ₀ and the number of layers n, increasing the number of layers the layer specific period as a predetermined specific period can be seen to increase.

交条件より、ζ_ｉとζ_０の比は次式で表される。

From the intersection condition, the ratio between ζ _i and ζ ₀ is expressed by the following equation.

From Equation 13, it can be seen that the viscous damping constant of System-CS is determined by the layer viscous damping constant ζ ₀ and the number n of layers, and the viscosity damping constant decreases when the number of layers is increased with the layer viscous damping constant being constant.

(2) Bending cantilevered shear structure a) Natural period and natural vibration mode Here, the number of layers n related to the natural period is set to 2 based on Equation 12 without changing the height h _total of the shear structure. Consider doubling the primary natural period of the structure by doubling. The vibration model shown in FIG. 3 is a bent cantilever shear structure in which a shear structure F having a lower end fixed to a base and a shear structure R having a lower end supported by a roller on the base in a vertical direction are coupled to each other at the upper end. It is. The shear structure R is obtained by cutting the lower end of the shear structure F from the base, and adding a beam supported by a roller in the vertical direction and movable in the horizontal direction at the lower end. Note that FIG. 3 is an image at the time of deformation, and the column before the deformation is straight.

The number of the beam of the shear structure F is 1, 2,..., N from the lower end to the upper end, and the number of the beam of the shear structure R is n, n + 1,. The beam n is a beam common to the shear structures F and R, and the beam 2n is a beam supported in the vertical direction by a roller. Mass of columns and beams can be concentrated into a beam in each layer, the mass of the beam (2n-1) from the beam 1 from the beam (n-1) and beams (n + 1) and _{m A.} Each mass beam n and beam 2n, and (1 + α) _{m A} and (1 + β) _{m A.} α and β are mass coefficients representing an increase in mass for connecting the beams n at the upper ends of the shear structures F and R and an increase in mass for moving the beam 2n on the roller, respectively. The viscous damping coefficient and the shear spring constant of the dash pots in each layer are all equal, and are c _A and k _A , respectively. And x _i the horizontal displacement of the beam i, as shown in FIG.

ここに、σは比例定数とする。The vibration model in FIG. 3 is referred to as System-FR. The dynamic characteristics of a single layer of System-FR are similar to those of System-CS, and it is assumed that equations 1a and 1b hold, and m _A and k _A and c _A have an order relationship.

Here, σ is a proportionality constant.

The equation of motion when the base produces a horizontal displacement z (t) in System-FR is shown by the following equation.

質量行列とする。

ここで、数１６ｄの行列Ｂ^（２ｎ）はｎ番目と２ｎ番目の対角要素の値がそれぞれαとβであり、他の要素の値が全てゼロである２ｎ次の行列とする。Where f is a Coulomb that models the rolling resistance of the roller against the horizontal movement of the beam 2n.

Let it be a mass matrix.

Here, the matrix B ⁽²ⁿ⁾ of Expression 16d is a 2n-order matrix in which the values of the n-th and 2n-th diagonal elements are α and β, respectively, and the values of the other elements are all zero.

In the System-FR, the eigenvalue problem of the non-damped system ignoring the Coulomb friction force and the viscous damping force is as follows.

である。数１６ａと数１６ｃを用いると数１７は次式に変形される。

It is. Using Equations 16a and 16c, Equation 17 is transformed into the following equation.

Further, the ratio between the natural circular frequency ω _{FR, i} and the layer natural circular frequency ω ₀ , the ratio between the natural period T _{FR, i} and the layer natural period T ₀ , and the natural _value λ _{FR, i} have the following relationship. .

Note that the proportionality constant σ representing the mass of the structure, the shear spring constant, and the viscosity damping constant shown in Expression 14 does not affect the ratio between the natural period and the layer natural period expressed in Expression 21.
Under the condition of α = β = 0, the eigenvalues and eigenvectors of Equation 18 are equal to those obtained by replacing n with 2n in Equations 9 and 10b, respectively. Therefore, the natural period of System-FR is about 2 of the natural period of System-CS. It turns out that it becomes double.

FIG. 4 shows the relationship between the natural period from the first order to the third order and the number of layers n in the System-CS and the System-FR, as shown in Expressions 8 and 21. The number n of layers here also represents the geometric height h _total of the structure. System-FR indicates a ratio of natural periods calculated under two conditions of α = β = 0 and α = 2, β = 1. The natural period of the former condition is calculated using Equations 8 and 9. Under the latter condition, the eigenvalue λ _FR is obtained from Equation 18 by numerical calculation and organized by Equation 21. The numerical method for the eigenvalue problem was a solution that combined the Householder method and the QR method. From FIG. 4, it can be seen that if the layer natural period T ₀ is constant, the natural period of System-FR is about twice the natural period of System-CS and increases in proportion to the number of layers n. It can be seen that the natural period is slightly larger than α = β = 0 under the conditions of α = 2 and β = 1 in System-FR.

ため、固定側のせん断構造体Ｆの梁を●印で、ローラー側のせん断構造体Ｒの梁を○印で表示する。１次モードは梁２ｎと梁ｎが同方向に変位する逆Ｖ字形、２次モードは梁２ｎと梁ｎが反対方向に変位する細長い０字形、３次モードはｌ字形、４次モードは「く」の字に曲がった８字形の振動モードとなることが分かる。FIG. 5 shows the eigenvectors of the non-damped system from the first order to the fourth order of the System-FR under the conditions of α = β = 0 and n = 10.

Therefore, the beam of the shear structure F on the fixed side is indicated by ● and the beam of the shear structure R on the roller side is indicated by ○. The primary mode is an inverted V shape in which the beam 2n and the beam n are displaced in the same direction, the secondary mode is an elongated 0 character in which the beam 2n and the beam n are displaced in the opposite direction, the third mode is an l shape, and the fourth mode is “ It turns out that it becomes the vibration mode of the 8-character shape bent to the character of "ku".

る粘性減衰定数ζ_{ＦＲ−ｃ，ｉ}とクーロン摩擦力ｆによる減衰を評価する等価粘性減衰定数ζ_{ＦＲ−ｆ，ｉ}に分けて考える。数２０ａと数２０ｂの固有ベクトルの直交条件より、ζ_{ＦＲ−ｃ，ｉ}と層粘性層粘性減衰定数ζ_０の比は数２２で表される。

なお、数１４で示した構造体の質量とせん断バネ定数および減衰定数の大きさを表す比例定数σは数２２の関係に影響を及ぼさない。b) Viscosity damping constant

The viscous damping constant ζ _{FR-c, i} and the equivalent viscous damping constant ζ _{FR-f, i} for evaluating the damping due to the Coulomb friction force f are considered. From the orthogonal condition of the eigenvectors of Equations 20a and 20b, the ratio between ζ _{FR-c, i} and the layer viscous layer viscous damping constant ζ ₀ is expressed by Equation 22.

Note that the proportionality constant σ representing the magnitude of the structure, the shear spring constant, and the damping constant shown in Equation 14 does not affect the relationship in Equation 22.

ベて若干小さくなるものの、_ｎ＞１０においては大きな違いは見られない。FIG. 6 shows the relationship between the first-order to third-order viscous damping constants of the System-CS and System-FR and the number _n of layers, which is obtained by Equation 22. System-FR conditions are the same as those in FIG. It can be seen that if the layer viscous damping constant ζ ₀ is constant, the damping constant of the System-FR is about ½ of the damping constant of the System-CS and decreases in inverse proportion to the increase in the number of layers _n .

Although it is slightly smaller, there is no significant difference when _n > 10.

ｃ_ｅ，ｉは次式で表される。

であり、着目する梁ｊの振幅をａ_ｊとすると、次式で近似できる。

c) Coulomb friction force and equivalent viscous damping constant The amount of energy that disappears during one cycle of the vibration system in which the Coulomb friction force f acts disappears during one cycle of the damping vibration system with an equivalent viscous damping coefficient. Assuming

c _{e, i} is expressed by the following equation.

If the amplitude of the beam j of interest is a _j , it can be approximated by the following equation.

When the number (23) and the number (24) are applied to the number (26a), the following equation is obtained.

If the roller has a braking function, the Coulomb friction force f can be adjusted to an arbitrary magnitude, but in the present embodiment, f is considered to be a force proportional to the vertical force acting on the roller. That is, if the vertical force acting on the roller of the System-FR is p _ν and the dynamic friction coefficient of the roller is μ, f is expressed by the following equation.

ここに、γはローラーに作用する鉛直力の大きさを表す係数である。ローラーの動摩擦係数が与えられれば、数２６ｂによりクーロン摩擦力による減衰を等価粘性減衰定数として評価することが可能と考えられる。The vertical force p _ν is obtained by multiplying the sum of the mass of the beam n by 1/2 and the mass of the beam n + 1 to the beam 2n by the gravitational acceleration g, and is expressed by the following equation.

Here, γ is a coefficient representing the magnitude of the vertical force acting on the roller. If the dynamic friction coefficient of the roller is given, it is considered that the attenuation due to the Coulomb friction force can be evaluated as an equivalent viscous damping constant according to Equation 26b.

(3) Countermeasure against increased attenuation by horizontal arrangement of dashpot In the previous section, the natural period of a bent cantilever shear structure whose free end is supported by a roller in the vertical direction is approximately twice the natural period of a normal cantilever shear structure. However, the viscosity damping constant was about ½. Increasing the natural period in a region exceeding about 1 second results in a decrease in seismic force, while an increase in displacement amplitude due to a decrease in rigidity in the horizontal direction. In addition, since a decrease in the viscous damping constant leads to an increase in the displacement amplitude, a measure for reducing the displacement amplitude is necessary.

In general, since the low-order natural vibration mode greatly contributes to the displacement, attention is paid to the low-order natural vibration mode, and an increase in attenuation due to the installation of a dashpot as a damping device is considered. In order to maximize the performance of the dashpot, it is necessary to install the dashpot where the relative displacement is large. As shown in FIG. 7, a large relative displacement occurs between the beam of the structure F and the beam of the structure R at the same height from the shape of the primary and secondary natural vibration modes of the System-FR in FIG. It is considered possible to increase the attenuation by connecting the left and right adjacent beam by a dash pot c _B. This arrangement of the attenuation device is called a horizontal arrangement. It is assumed that c _B is a dash pot viscous damping coefficient and has the following relationship with the existing dash pot viscous damping coefficient c _A.

Here, τ is a proportionality constant. The vibration model in FIG. 7 is referred to as System-DFR. The equation of motion when the base produces a horizontal displacement z (t) in the System-DFR is expressed by the following equation.

有値解析^５）により評価できるが、Ｓｙｓｔｅｍ−ＤＦＲではクーロン摩擦力が非線形項として作用するので、複素固有値解析においてもこの非線形項の影響は考慮できない。本実施形態で

数３３には、減衰係数ｃ_Ｂの大きさを表す比例係数σは影響を及ぼさない。Since the system-DFR is a non-proportional damped oscillation system due to the arrangement characteristics of the matrix D ⁽²ⁿ⁾ of ^Equation 32b,

Although it can be evaluated by the value analysis ⁵⁾ , since Coulomb frictional force acts as a nonlinear term in the System-DFR, the influence of this nonlinear term cannot be taken into account even in the complex eigenvalue analysis. In this embodiment

In the equation 33, the proportionality coefficient σ representing the magnitude of the attenuation coefficient c _B has no effect.

FIG. 8 shows the relationship between the viscosity damping constant ζ _{FR-d, i} of the System-DFR and the number n of layers under the conditions of α = β = 0 and τ = 1. For comparison, ζ _{FR-c, i} (α = β = 0) of System- _FR and ζ _{i of} System-CS shown in FIG. 6 are also shown. When the layer viscous damping constant ζ ₀ is constant, ζ _{FR-c, i} and ζ _i decrease in inverse proportion to the increase in the number of layers n, whereas ζ _{FR-d, i} increases in the number of layers n. It can be seen that it increases in proportion. Since tau = 1 condition means that the viscous damping coefficient is placed dashpot c _A, horizontal arrangement of the dashpot c _B as compared with the vertical surface disposed dashpot c _A is efficiently damped It is thought to increase.

ζ_{ＤＦＲ，ｉ}＝ζ_ＤＦ，ｉ＋ζ_{ＤＦ−ｄ，ｉ}となるので、数２９より次式で評価する。

Since ζ _{DFR, i} = ζ _{DF, i} + ζ _{DF−d, i} , the following equation is evaluated from Equation 29.

  Embodiments according to the present invention will be described below with reference to the drawings. 9 is a schematic front explanatory view of the earthquake-resistant structure ST according to the present embodiment, and FIGS. 10A, 10B, and 10C are cross-sectional explanatory views taken along the line II of FIG. 9, and II-II. It is line sectional explanatory drawing and III-III line sectional explanatory drawing.

  As shown in FIG. 9, the earthquake-resistant structure ST is configured by supporting an upper structure 11 which is mainly a frame structure and resists vertical and horizontal loads mainly on a lower structure 10 such as a foundation or an underground structure. It is a structure. Then, as shown in FIG. 10, the upper structure 11 includes a fixed end side shear structure F (hereinafter sometimes simply referred to as “shear structure F”) and a free end side shear structure R (hereinafter simply referred to as “shear structure F”). May be referred to as “shear structure R”), and may be referred to simply as “cantilever shear structure DFR” (hereinafter simply referred to as “cantilever shear structure DFR”). In this embodiment, a pair of left and right cantilever shear structures DFR and DFR are disposed at left and right symmetrical positions, and a pair of fixed end side shear structures F and F are disposed. Both free end-side shear structures R, R are disposed between the shear structures F, F, and the free end-side shear structures R, R are integrally formed.

  That is, as shown in FIGS. 9 and 10, the cantilever shear structure DFR has a fixed structure composed of a plurality of layers (10 layers in this embodiment) in which the lowermost floor on the fixed end side is fixed to the lower structure 10. A fixed-end-side shear structure F is formed by the end-side layer portion 12 and the bent portion forming layer 13 that forms the upper floor (in this embodiment, the uppermost floor) of the fixed-end-side layer portion 12, Is formed, and a free end side layer portion 14 composed of a plurality of layers (10 layers in this embodiment) in which the lowermost floor on the free end side is supported by the lower structure 10 so as to be horizontally movable. And the free end side shearing structure R is formed.

  And the fixed end side hierarchy part 12 is the pillar part 15 extended to an up-down direction (Z direction shown in FIG. 10), and the beam part (or X direction and Y direction shown in FIG. 10) extended to the left-right and front-back direction (or X direction). Each layer portion formed by assembling the (floor portion) 16 is constructed in a stacked state in the vertical direction. Similarly, the free end side layer portion 14 is formed by assembling each layer portion formed by assembling a column portion 17 extending in the up-down direction and a beam portion (or floor portion) 18 extending in the left-right and front-back directions in the up-down direction. It is constructed in a stacked state. The bent portion forming layer 13 includes a beam portion (or floor) between a column portion 15 that forms the uppermost layer of the fixed end side layer portion 12 and a column portion 17 that forms the uppermost layer of the free end side layer portion 14. Part) 19 is provided.

  Moreover, in the present embodiment, the free end side layer portion 14 is formed so as to have a larger mass than the fixed end side layer portion 12 so that the natural period of the cantilever shear structure DFR becomes longer. ing. Specifically, the mass of the free end side layer portion 14 related to the natural period is increased by increasing the floor area of the free end side layer portion 14. The floor area is increased by enlarging the room and increasing the number of rooms. Further, the floor area can be increased by increasing the number of floors of the free end side layer portion 14.

  Here, when the mass of the free end side layer portion 14 is increased, the load of the seismic force of the fixed end side layer portion 12 is also increased, but the horizontal mass (fixed) that the fixed end side layer portion 12 bears is fixed. The seismic force on the side is increased as appropriate, and the attenuation is greatly increased to reduce the greater seismic force. In the present embodiment, since the basic structural form is the cantilever shear structure DFR, the fixed end side layer portion 12 and the free end side layer portion 14 forming a part thereof are appropriately adjusted as described above. be able to. As a result, a large seismic force can be reduced steadily.

  Furthermore, in the present embodiment, the lower structure 10 is provided with an accommodation recess 29 that accommodates the lower floor of the free end side layer portion 14 in a stepped recess shape, and the accommodation recess 29 is provided with the uppermost portion of the free end side layer portion 14. The floor portion 28 of the lower floor is supported so as to be horizontally movable, and the ground height levels of the beam portions 16 and 18 of each layer of the fixed end side layer portion 12 and the free end side layer portion 14 are matched.

  In addition, the accommodation recess 29 can effectively use the space inside the accommodation recess 29, and appropriately accommodates the lowermost floor of the free end side layer portion 14 in the accommodation recess 29, so that the lowermost floor The ground height can be lowered from the ground height of the lowest floor of the fixed end side layer portion 12. Therefore, the number of floors and the height from the lowest floor to the top floor of the free end side hierarchy part 14 is made larger than the number of floors and the height from the bottom floor to the top floor of the fixed end side hierarchy part 12. You can also.

  Also from this point, in the cantilever shear structure DFR according to the present embodiment, by increasing the total number of floors of the fixed end side layer portion 12 and the free end side layer portion 14 or as described above. The natural period can also be increased by increasing the mass of the free end side layer 14. Therefore, by increasing the number of floors of the free end side layer part 14 regardless of the number of floors and the height of the fixed end side layer part 12, the number of floors and mass related to the natural period are increased, and the cantilever shear structure The natural period of the DFR can be lengthened.

  A plurality of horizontal movable support devices M are provided on the lowermost floor of the free end side layer portion 14, and the receiving recesses 29 provided in the lower structure 10 are connected to the free end side layer via these horizontal movable support devices M. The part 14 is supported so as to be horizontally movable in the X and Y directions shown in FIG. Here, as shown in FIG. 11, the horizontal movable support device M is a roller unit including a large number of carbon steel spherical rollers 21 a on a horizontal plate-like lower collar portion 20 disposed on the lower structure 10. 21 is placed so as to be able to roll in the left and right and front and rear directions (X direction and Y direction shown in FIG. 10), and an upper collar part 22 is placed on the roller part 21 so that the upper collar part 22 is a free end. It is configured to be connected to the floor portion 28 of the lowest floor of the side layer portion 14.

  Further, in order to adjust the friction damping of the cantilever shear structure DFR, a part of the horizontal movable support device M can be replaced with a sliding friction type horizontal movable support device L as shown in FIG.

  As shown in FIG. 12, the sliding friction type horizontal movable support device L fixes the lower collar part 53 to which the sliding plate 53a is fixed or fixed to the lower structure 10 and the upper collar part 55 to the free end side layer part 14. Is fixed to the lowermost floor, and the sliding plate 54a is fixed or fixed so that the sliding plate 53a and the sliding plate 54a are in contact with each other, and the centers of the upper flange portion 55 and the middle flange portion 54 are aligned. To be placed.

  Since the Coulomb friction force is generated at the contact surface between the sliding plate 55a and the sliding plate 56a, the sliding friction type horizontal movable support device L has a larger coefficient of friction than the rolling movable type horizontal movable support device M. Accordingly, the friction damping of the cantilevered shear structure DFR can be adjusted by using the horizontal movable support devices M and L of different types having different friction coefficients.

  A horizontally movable support device M is accommodated in the accommodation recess 29 formed in the lower structure 10 so as to be movable horizontally. A plurality of damping devices Na are interposed between the floor 28 on the lowest floor of the free end side layer 14 and the accommodating recess 29 of the lower structure 10.

  Here, the damping device Na is arranged in the middle of the horizontal movable support devices M adjacent to each other in plan view, that is, arranged so that the damping force acts on the entire surface of the floor portion 28 on the lowest floor. (See FIG. 9 and FIG. 10C.) Therefore, as the attenuation device Na, a large attenuation device that can effectively use the unused space between the floor portion 28 and the lower structure 10 can be used. Further, since the horizontal relative displacement in the primary natural vibration mode is maximized between the floor portion 28 and the lower structure 10, the damping device Na increases the damping constant of the primary natural vibration mode most efficiently. Further, since the floor portion 28 is displaced in each direction of the X direction and the Y direction shown in FIG. 10, the attenuation device Na needs to be effective for displacement in each direction of the X direction and the Y direction.

  Specifically, as shown in FIGS. 13 (a) and 13 (b), the damping device Na is formed in a flat cylindrical shape with a circular top view and an open top surface as shown in FIGS. A viscous fluid case 25 having a connecting portion 25a, a viscous fluid (not shown) accommodated in the viscous fluid case 25, and a horizontal plane in the viscous fluid case 25 in the X and Y directions shown in FIG. A slide body 26 is slidably accommodated through the oil. The slide body 26 has a connecting portion 26a at the upper end. When the damping device Na is provided, the connecting portion 25a of the viscous fluid case 25 is connected to one of the lower structure 10 or the object to be attenuated of the pedestal 10a provided on the lower structure 10 for height adjustment. The connecting portion 26a is connected to the other of the attenuation objects such as the beam portion and the floor portion. Reference numerals 25b and 26b denote connecting holes. As the viscous fluid, oil that is a fluid having a required viscosity can be used. By appropriately setting the fluid viscosity and the interval between the fluid of the slide body 26 and the fluid case 25, the shear structure A viscous damping coefficient necessary for increasing damping can be obtained. Therefore, the damping device Na can generate an effective damping force for all horizontal displacements of the floor portion 28.

  9 and FIG. 10 between at least one pair of opposing layers (in the present embodiment, 1 to 8 layers) among the opposing layers of the fixed end side layer unit 12 and the free end side layer unit 14. As shown in FIG. 2, the layers are connected in the horizontal direction with a plurality of attenuation devices Nb interposed therebetween. That is, the cantilever portion 23 is formed to extend from the beam portion 16 of the fixed end side layer portion 12 to the free end side layer portion 14 side while being cantilevered from the beam portion 18 of the free end side layer portion 14. The beam portion 24 is formed so as to extend to the fixed end side layer portion 12 side, and both the cantilever beam portions 23 and 24 are arranged in an opposed state on substantially the same horizontal plane. , 24 is provided with an attenuation device Nb and a floor extension device FE. The floor extension device FE is a device that closes the gap between the cantilever portions 23 and 24 indicated by the symbol FE in FIG. 9, and only the symbol FE is shown in the drawing.

  The purpose of forming both cantilever portions 23 and 24 is to use floor portions 61 and 63 between the fixed side layer portion 12 and the free end layer portion 14 using these cantilever portions as shown in FIG. It is to increase living space and accommodation space by forming. The floor portions 61 and 63 are obtained by adding a floor on the cantilever portion 23 or the cantilever portion 24 and reinforcing the ends and intermediate portions of the floor with floor beams or the like as necessary. Therefore, it can be easily installed with the existing technology. Therefore, the details of the method for forming the floor portions 61 and 63 are omitted. First, the type, arrangement, and mounting method of the damping device Nb will be described with reference to FIG. 14, and the structure of the floor expansion / contraction device FE will be described with reference to FIG.

  The purpose of installing the damping device Nb is to efficiently increase the damping constant of the secondary and subsequent natural vibration modes in addition to the primary natural vibration mode. Since it is desirable to install the attenuation device Nb in a space between the lower surfaces of the floor portions 61 and 63 and the ceiling below the floor devices 61 and 63, it is convenient to use an attenuation device having a compact outer shape. Further, since the fixed end side layer portion 12 and the free end side layer portion 14 are displaced in the X direction and the Y direction shown in FIG. 10, respectively, the attenuation device Nb must be effective for all horizontal relative displacements. I must.

  Here, it is assumed that the damping device Nb uses a high-performance and compact-shaped oil damper that utilizes pressure drop due to turbulent fluid flow, and the arrangement thereof is shown in cross-sectional side view (a) in FIG. This is shown in the explanatory diagram (b). The bottom view (b) shows the arrangement of the attenuation device Nb when the bottom surfaces of the floor portions 61 and 63 to which the attenuation device Nb is attached are viewed from below. The attenuation device Nb is composed of two main bodies 64 having connecting portions 64a and 64b at both ends. The connecting portion 64a is connected to a floor beam 60 installed on the floor portion 61 via a bracket 65a, and the connecting portion 64b is connected to a floor beam 62 installed on the floor portion 63 via a bracket 65b. . The floor portion 61 is a floor portion installed on either the cantilever portion 23 or the cantilever portion 24, and the floor portion 63 is a floor portion installed on the remaining one cantilever portion. The cross-sectional shape of the floor beams 60 and 62 may be a cross-section having an arbitrary shape such as a solid cross-section, a thin cross-section, an open cross-section, or a closed cross-section. The brackets 65a and 65b may be directly attached to the floor portions 61 and 63 instead of the floor beams 60 and 62. The description of the structure of the damping device main body, the coupling method of the damping device and the bracket, and the fixing method of the bracket and the floor beam will be omitted.

  Further, in order to correspond to the respective displacements in the X direction and the Y direction in the figure, the two adjacent main bodies 64 and a part of the floor beam 60 are each of a triangular shape having two brackets 65a and 65b as vertices. Arrange them to be on the sides. The operating direction of the main body 64 of the damping device Nb is a direction connecting the connecting portion 64a and the connecting portion 64b, and the direction intersects both the X direction and the Y direction in the drawing, so The damping device Nb operates effectively. When the required attenuation performances in the X direction and the Y direction are different, the angles of the two main bodies 64 are adjusted.

  The two main bodies 64 that form two sides of the triangle are set as one set, and the number of sets necessary for increasing attenuation is set. When the required number of sets is small, at least two sets are used in order to distribute the damping force in the Y direction and to act efficiently, and the sets do not share a bracket, that is, they are separated from each other in the Y direction. It is good to install.

  Here, the types and arrangements of the damping device Na and the damping device Nb are not limited to the viscous damping device, the oil damper, and their arrangement as shown in this embodiment, but other types of damping devices and their performance. It can also be arranged to maximize the performance.

  The purpose of installing the floor extension device FE is to close the gap Ga between the cantilever portion 23 of the fixed end side layer portion 12 and the cantilever portion 24 of the free end side layer portion 14 as shown in FIG. In other words, the floor portions 61 and 63 installed in the cantilever portions 23 and 24 should not be hindered as a living space or a storage space. In addition, the floor expansion and contraction device FE has a restoring force that shortens the natural period of the shear structure with respect to the horizontal relative displacement between the fixed end side layer portion 12 and the free end side layer portion 14 on the fixed end side. It is required not to act on the layer portion 12 and the free end side layer portion 14.

  As shown in the plan explanatory view (a) and the sectional side view (b) of FIG. A storage recess 61 a for fixing the moving material 72 is provided, a storage recess 63 a for fixing the connecting plate 70 is provided on the floor 63 facing the floor 61, the connecting plate 70 is fixed to the storing recess 63 a, and the tip of the connecting plate 70 A viscoelastic material 71 having a structure in which the portion 70b is placed on a sliding member 72 fixed to the housing recess 61a and easily deformed into the housing recess 61 on the front and side of the front end portion 70b of the connecting plate. Filled. Since the viscoelastic material 71 in front and side of the front end portion 70b of the connecting plate is deformed in accordance with the horizontal relative displacement between the floor portion 61 and the floor portion 63, for example, by using a silicon-based sealing material or the like as the viscoelastic material 71 The restoring force generated by the deformation of the viscoelastic material 71 can be reduced to such an extent that it does not affect the natural period of the shear structure.

  The combination of the material of the sliding material 72 and the connection plate 70 can be, for example, a fluororesin plate and a stainless plate. Alternatively, in order to reduce the material cost of the coupling plate, another sliding material that matches the sliding material 72 may be fixed or fixed only on the surface of the coupling plate 70 that contacts the sliding material 72. If the friction coefficient between the sliding member 72 and the connecting plate 70 is constant and quantitative over time, the Coulomb friction force generated by the sliding member 72 and the connecting plate 70 is reduced by the damping of the shear structure. May be considered.

  Next, the structure of the outer wall that covers the shear structure of the present invention will be described. In the gap Ga between the cantilever part 23 and the cantilever part 24 opposite to each other below the section II-II shown in FIG. 9, that is, the gap indicated by the symbol FE, the fixed end side layer part 12 and the free end side layer part 14 are horizontally Since a large gap Ga change due to relative displacement occurs, and the entire side surface of the shear structure parallel to the frame surface in FIG. 9 must be covered with a side outer wall in order to prevent intrusion of wind and rain, etc., section II-II On the same side outer wall in the vicinity and below it, the fixed end side is between the side wall surface installed on the fixed end side layer portion 12 and the side surface outer wall installed on the free end side layer portion 14 opposite to the side surface outer wall. A gap Ga that absorbs the horizontal relative displacement between the layer portion 12 and the free end side layer portion 14 is provided, and the gap Ga is closed by the outer wall expansion and contraction device WE shown in FIG.

  As shown in the side explanatory view (a) and the cross-sectional bottom explanatory view (b) as seen from the inside to the outside in FIG. 16, the outer wall expansion and contraction device WE is connected to each other from the opposite fixed end side layer portion and free end side layer portion. The lateral outer wall 82 is extended in the horizontal direction, a gap Ga for absorbing horizontal relative displacement is provided, or the base frame 83 to which the side outer wall 81 is attached from the opposite fixed end side layer portion and free end side layer portion is horizontally disposed. A gap Ga that absorbs horizontal relative displacement is provided, and stretched side outer walls 82 or stretched base frames 83 are interposed with an elastic member 80 formed so as to be easily deformable. To be connected.

  FIG. 16 shows an example in which the base frame 83 and the side outer wall 82 are connected, and the method for connecting the base frame 83 and the method for connecting the side outer wall 82 are simultaneously described. The base frame 83 and the elastic member 80 are connected to each other by connecting the cap nut 83b fixed to the bracket 83a attached to the base frame 83 by extending vertically and the connecting hole 80a of the elastic member 80, a holding plate 84, a bolt, etc. (Omitted). It is also possible to connect using a stud bolt or the like instead of the cap nut 83a. The side outer wall 82 and the expansion / contraction material 80 are connected by connecting the cap nut 82a embedded in the side outer wall 82 and the connection hole 80a of the expansion / contraction material 80 with a pressing plate 84 and bolts (not shown). It is also possible to connect using embedded bolts instead of the cap nut 82a.

  The elastic member 80 is formed as a cross-sectional shape that can be easily deformed, for example, a cross-sectional shape shown in FIG. Therefore, by appropriately selecting the material and the cross-sectional shape of the stretchable material 80, the restoring force generated by the deformation of the stretchable material 80 in the X direction and the Y direction in the drawing is reduced to an extent that does not affect the natural period of the shear structure. be able to.

  In addition, if the vibration energy absorption resulting from plastic deformation of the stretchable material 80 generated due to the horizontal relative displacement is constant and quantitative over time, the attenuation due to this may be considered as the attenuation of the shear structure. .

  As in the present embodiment described above, the pair of left and right bent cantilever shear structures DFR, DFR are positioned such that the fixed end side layer portion 12 is outward and the free end side layer portion 14 is inward. As described above, the configuration is not limited to the symmetrical arrangement, and a bent cantilever shear structure DFR may be added forward and / or backward. In addition, a large number of bent cantilever shear structures DFR may be arranged and arranged radially such that the fixed end side layer portion 12 is located outward and the free end side layer portion 14 is located inward. it can. At this time, the fixed end side layer portions 12 adjacent to each other in the circumferential direction may be integrally connected to form a cylindrical shape surrounding the free end side layer portion 14. Even in such a configuration, it is possible to provide an earthquake-resistant structure having a long period and a high attenuation.

  The upper structure 11 is a frame structure that is resistant to main vertical loads and horizontal loads, and has partially a shear wall 51 or diagonal members 52 for resisting a large local shear force. You may do it (refer FIG. 9).

[Experimental example]
Below, the result of the vibration experiment performed using the reduced model of the earthquake-resistant structure ST as a present Example is demonstrated.

(1) Purpose of the experiment To verify the increase in attenuation due to the long period of the natural vibration mode to be realized by the structure DFR as the embodiment and the horizontal arrangement of the viscous damping device B applied to the structure DFR. In addition, a vibration experiment was performed using a reduced model. In the vibration experiment, we conducted a free vibration experiment to verify the calculation formula of natural period and damping constant obtained by vibration theory and a shaking table shaking experiment to verify the shape of natural vibration mode. In the free vibration experiment, we observed the free vibration of the reduced model after hand vibration, calculated the natural period and viscosity damping constant from the observed free vibration waveform, and compared them with the calculated values by vibration theory. In the shaking table shaking experiment, the steady vibration of the reduced model due to the sinusoidal shaking of the shaking table was observed, and the shape and phase shift of the natural vibration mode were calculated from the steady-state vibration records and compared with the shape of the vibration theory. . However, a theoretical formula is not shown for the phase shift, so qualitative properties obtained through experiments will be described.

  A laser displacement meter (measurement range ± 10 mm, resolution 0.002 mm) was used for vibration measurement, and a conductive vibration generator from Kumamoto University was used for the vibration table experiment.

(2) Specifications of Reduced Model a) Specifications of Bending Shear Structure Model FIG. 17 is an explanatory view of the appearance of a bent cantilever shear structure DFR. The shear structures F and F are erected, the shear structure R is arranged between the two shear structures F and F, and the beam portions 31 and 31 at the upper ends of the two shear structures F and F are connected to the shear structure. The beam portion 32 at the upper end of R is connected by a bolt 33 extending in the left-right direction. This model is a plane vibration model in which the rigidity in the direction of the arrow of the horizontal load is smaller than the rigidity in the direction perpendicular to the arrow and vibrates in the direction of the arrow. At the lower end of the shear structure R, a horizontal movable support device 34 having a roller 43 is provided. Details of the horizontal movable support device 34 will be described later.

FIG. 17 is an exaggerated depiction of the state of deformation when a horizontal load is applied to the free end of the bent cantilever shear structure DFR. In order to facilitate understanding of the positional relationship between the shear structure F and the shear structure R and the direction of deformation, the beam portions 31 and 32, the column portions 35 and 36, and the roller 43 are emphasized, and other members are omitted. Yes. In this figure, reference to the fixed end, the shear structure F and the horizontal displacement x ₅ of the upper end of the beam portion 31,31,32 of R, the horizontal displacement of the beam portion 37 or free end of the lower end of the shear structure R x ₁₀ is illustrated. This deformation is very similar to the primary natural vibration mode shown in FIG. It should be noted that the horizontal displacement direction in this figure is the vibration direction of the model.

  Aluminum column FB20 × 2 × 894 mm (A6063) made of aluminum alloy was used for the column portions 35 and 36 of the model, and polished flat steel FB44 × 19 × 240 mm (SS400) was used for the beam portions 31 and 32. The column portions 35 and 36 of the model were fixed to the end faces of the beam portions 31 and 32 by using two bolts (M8, strength category 10.9) per place. Details of the viscous damping device A and the viscous damping device B shown in FIGS. 18 and 19 will be described later.

  Table 1 shows the specifications of the structure model mainly related to the natural period. The shear spring constant and the layer natural period described in Table 1 are values obtained by a static loading test of the model. Details will be described in the next section.

b) Specifications of Horizontal Movable Support Device The horizontal movable support device 34 includes a lower rail 38, a roller vehicle body 39, and an upper rail 40 as shown in FIG. 20. The upper and lower rails 40 and 38 were made of polished flat steel 50 × 16 (SS400). The roller body 39 has four flanged rollers 43 with a diameter of 20 mm attached to an aluminum alloy frame 41 via a shaft 42. The material of the shaft 42 and the roller 43 is carbon steel (SC450). The shaft interval is 180 mm and the rail width is 50 mm. The upper rail 40 is fixed to the beam portion 37 at the lower end of the shearing structure R with bolts (not shown).

FIG. 21 is a frequency distribution diagram of the dynamic friction coefficient of the roller vehicle body 39 obtained by the tilt method. This is measured by a laser displacement meter while the roller vehicle body 39 carrying a weight corresponding to the self-weight of the shear structure F shown in Table 1, that is, the vertical force p _ν = 259N, moves slightly on the slope. The dynamic friction coefficient is estimated from the trajectory of the motion. The coefficient of dynamic friction obtained in the experiment was distributed in the range of 0.1 to 0.3 × 10 ⁻³ , and the distribution was almost a normal distribution. The average value of the dynamic friction coefficient is 0.2 × 10 ⁻³ . Incidentally, the coefficient of static friction is distributed in 0.4 to 0.5 × ^{10 -3,} the average value is 4.5 × ^{10 -3.}

    c) Specifications of the viscous damping device

The appearance of the viscous damping device A corresponding to dashpot _{c A} of System-FR shown in FIG. 3 shown in FIG. 22. The viscous damping device A includes an oil casing 44 as a viscous fluid case made of a transparent acrylic plate and a parallel plate 45 as a slide body.

The appearance of the viscous damping device B corresponding to the dashpot _{c B} of System-DFR shown in FIG. 7 is shown in FIG. 23. The viscosity damping device B includes an oil casing 46 as a viscous fluid case made of aluminum alloy (A6063), a parallel plate 47 as a slide body, and a connecting body 48. These two viscous damping devices A and B are both viscous and parallel plate type damping devices that utilize shear deformation of dimethyl silicone oil filled in oil casings 44 and 46.

  FIG. 18 is a layout diagram of the viscous damping devices A and B in a cross section perpendicular to the vibration direction of the model. In this figure, the shear structure R and the shear structure F are separated from each other for easy understanding of the arrangement of the damping device. In the actual structure, the reference line CL of the shear structure R and the reference line CL of the shear structure F overlap. The viscous damping device A is interposed between the beam portions 31 and 31 adjacent to each other in the vertical direction of the shear structure F and is installed outside the shear structure F. The viscous damping device B is interposed between the beam portions 31 and 32 adjacent to each other in the left-right direction of the shear structure F and the shear structure R.

FIG. 19 is an enlarged view of part a in FIG. 18, and the arrangement of the viscous damping devices A and B will be described in detail with reference to FIG. Since the viscous damping device A uses the relative speeds of the upper and lower beam portions 31, 31 of the shear structure F, the upper end of the slide body 45 is fixed to a connecting plate 49 fixed to the upper beam portion 31, and the slide body 45. Is inserted into the casing oil 44 fixed to the outer surface of the lower beam portion 31. This structure is repeated at all levels. However, although in order to reproduce the arrangement of the dashpot c _A of System-FR should be installed viscous damping device A shear structure R, since the installation space in the structure in the model is insufficient, the shearing structure R could not install the viscous damping device A.

  Since the viscous damping device B uses the relative speed of the beam portion 32 of the shear structure R and the beam portion 31 of the shear structure F, the connecting body 48 attached to the parallel plate 47 is adjacent to the shear structure F in the left-right direction. The lower end of the parallel plate 47 is disposed between the pair of left and right beam portions 32, 32 of the shear structure R. The oil casing 46 is inserted. Both the lateral connection frame 50 and the connection body 48 are made of aluminum alloy (A6063).

The viscous damping coefficient of the viscous damping devices A and B is calculated by the following equation.

Here, ε is the viscosity of the viscous fluid, and l, w, and s are the length of the parallel plate 47 and the contact depth of the fluid and the gap between the parallel plate 47 and the side wall of the oil casing 46 shown in FIG. The product obtained by multiplying the viscous damping coefficient c _device of the viscous damping apparatus A by the number of installed viscous damping apparatuses A per layer is the viscous damping coefficient of the dashpot c _A of the System-FR. Similarly, the product obtained by multiplying the viscosity damping coefficient c _device of the viscosity damping device B by the number of installed viscosity damping devices B per layer is the viscosity damping coefficient of the dashpot c _B of the System-FRD.

The design viscosity of the dimethyl silicone oil used in the experiment at a standard temperature of 25 ° C. is 9.75 N / m ² · s, but the temperature of the vibration model at the time of the experiment is 30 to 38 ° C., which is announced by the manufacturer of silicone oil. Considering the viscosity-temperature curve, the viscosity damping coefficient was calculated using a viscosity of 8.3 N / m ² · s at a temperature of 34 ° C. Table 2 summarizes the viscous damping coefficients of the viscous damping devices A and B and the viscous damping coefficient of the dashpot.

d) Definition of the vibration system in the reduced model The free vibration experiment and the shaking table vibration test were performed in the system-DFR and the system-DFR damping device B in which viscous damping devices A and B and a roller guide were attached to the bending shear structure model. This is performed for System-F, which is a vibration system in which the roller vehicle body is removed from System-FR and System-FR in which is invalidated. Further, in order to measure the structural damping of the structure model, a free vibration experiment of System-F0, which is a vibration system in which the viscous damping device A of System-F is disabled, is performed.

(3) Static loading test In order to measure the shear spring constant of the structural model, the relationship between the horizontal load acting on the free end shown in Fig. 17 and the horizontal displacement of the upper end and free end of the model is examined by a static loading test. It was.

FIG. 25 is an example of a load-displacement curve for one cycle of Syatem-FR and Syatem-F. In the history of Syatem-FR in FIG. 25 (a), a characteristic of the structural system in which the Coulomb friction force acts, that is, a gap between loading and unloading appears remarkably. Normally, the size of the gap is twice the static friction force, and therefore, when the size of the gap is calculated from the static friction coefficient 0.45 × 10 ^{−3 of} the roller guide and the vertical force p _ν = 259N acting on the roller, 0 is obtained. .23N, which roughly matches the size of the gap in the figure. Since the slopes of the hysteresis curves at the upper end (x ₅ ) and the free end (x ₁₀ ) are 2700 N / m and 1360 N / m, respectively, the shear spring constant k _A is calculated from these values to be 13.5 kN / m and 13.6 kN, respectively. / M.

On the other hand, in the history of Syatem-F in FIG. 25B, there is no gap between loading and unloading, and the relationship between load and displacement is linear. Since the slopes of the hysteresis curves at the upper end (x ₅ ) and the free end (x ₁₀ ) are 2200 N / m and 1260 N / m, respectively, the shear spring constant k _A is calculated from these values to be 11.0 kN / m and 12.6 kN, respectively. / M. The reason why the shear spring constant of Syatem-FR is larger than that of Syatem-F is considered that the roller restrains the axial deformation of the column in Syatem-FR. The shear spring constant k _A = 13.5 kN / m in Table 1 is calculated from the hysteresis curve at the upper end (x ₅ ) of Syatem-FR.

(4) Free vibration experiment focusing on the natural period and viscous damping constant a) Structural damping of the structural model First-order natural characteristic calculated from the system-F0 free vibration recording to measure the structural damping of the bending shear structural model FIG. 26 shows the relationship between the viscosity damping constant and amplitude of one waveform of vibration and the relationship between the natural period and amplitude of one waveform. The point of interest is the beam 5 at the upper end of the model. The viscous damping constant and the natural period of one waveform here are a viscous damping constant and a period calculated from the amplitude of the adjacent peak and the occurrence time of the peak in the displacement response time history, respectively. In the figure, experimental values are shown for every 10 peaks of the waveform in order to avoid complexity. It can be seen that the attenuation constant of System-F0 is constant regardless of the amplitude, and the structural attenuation is about 0.2%.

In addition, the natural period is constant regardless of the amplitude, and it is confirmed that the model vibrates as an elastic body. If 11.0 kN / m is adopted as the shear spring constant of Syatem-F0 and Syatem-F from the previous section, the layer natural period of these two vibration systems is calculated as T ₀ = 0.123 s. Using this layer natural period and the natural value λ _{FR, 1} = 0.01949 of System-FR, the primary natural period of System-F0 and System-F is calculated as T _{F, 1} = 0.88 s. This natural period agrees well with the experimental result of FIG. Table 3 shows the first and second order eigenvalues and the corresponding eigenvectors of the reduced model System-FR necessary for calculating the natural period.

b) Natural Period FIG. 27 shows a comparison of the relationship between the natural period and amplitude of one waveform of the primary natural vibration mode calculated from the free vibration records of System-DFR, System-FR, and System-F. The points of interest are the beam 5 at the upper end of the model and the beam 10 on the roller. Using the layer natural period T ₀ = 0.111 s of Table 1 and the natural _value λ _{FR, 1} = 0.01949 of Table 4, the primary natural period of System-DFR and System-FR is expressed as T _{FR, 1} = It is calculated as 0.795 s. As shown in the previous section, the primary natural period of System-F is calculated as T _{F, 1} = 0.88 s. From the figure, it can be seen that these two natural periods agree well with the experimental results.

c) Viscosity damping constant by dashpot As described in the specifications of the viscous damping device in the previous section, the viscous damping device A can be installed in the model shear structure F, but the damping device A cannot be installed in the shear structure R. so it can not reproduce the arrangement of the dashpot _{c a} of System-DFR and System-FR in the model. Model dash

の粘性減衰定数ζ_{ＦＲ−ｃ，ｉ}と層粘性減衰定数ζ_０の比を次式で近似する。

The ratio of the viscous damping constant ζ _{FR-c, i} to the layer viscous damping constant ζ ₀ is approximated by the following equation.

Table 4 summarizes various quantities and calculation results necessary for calculating the viscous damping constants of System-FR and System-DFR in the reduced model based on the vibration theory.

と梁の接合部で失われるエネルギー起因する構造減衰は含まれていない。よって、図２６で示したＳｙｓｔｅｍ−Ｆ０の振動実験により得られた粘性減衰定数ζ_ＦＯ，１＝０．００２を構造減衰として考慮し、これを表４に併記する。The layer viscous damping constant ζ ₀ was calculated under the conditions of m _A = 4.2 kg, k _A = 13.5 kN / m and c _A = 50.4 Ns / m. Sticky

It does not include structural damping due to energy lost at the beam joint. Therefore, the viscous damping constant ζ _{FO, 1} = 0.002 obtained by the vibration experiment of System-F0 shown in FIG. 26 is considered as structural damping, and this is also shown in Table 4.

FIG. 28 shows the relationship between the viscous damping constant and the amplitude of each waveform calculated from the free vibration recording of the vibration model for System-DFR, System-FR, and System-F with the theoretical value considering the structural damping of the model. It is a thing. The points of interest are the beam 5 at the upper end of the model and the beam 10 on the roller. The viscosity damping constant of System-F is about 1.9% regardless of the amplitude. Structural damping is because about 0.2%, viscous damping constant by dashpot _{c A} is about 1.7%. The attenuation constant of System-FR is about 2% when the dimensionless amplitude is about 1/100, and the attenuation constant gradually increases as the amplitude decreases. This is a manifestation of the characteristics of the vibration system including the Coulomb friction force. Since the theoretical value and the experimental value agree with each other, in the shearing structure of the present embodiment, the attenuation due to the rolling resistance of the roller can be evaluated as the equivalent viscous damping due to Equation 26b using the Coulomb friction force. it is conceivable that. However, since the dynamic friction coefficient of the roller guide used in the experiment is very small, it is considered that examination is necessary when the dynamic friction coefficient becomes large. The attenuation constant of System-DFR is distributed from 10% to 7%, but the attenuation is large where the amplitude is small, and the attenuation tends to decrease as the amplitude increases. Although the experimental value is about 10 to 15% smaller than the theoretical value, the relationship between the attenuation constant and the amplitude is qualitatively consistent. The reason why the theoretical value is lower than the experimental value is considered to be the evaluation method of the viscous damping constant in which the non-proportional damping is proportional to the diagonal approximation.

の比は約１３となる。これは図８で示したダッシュポットｃ_Ｂとダッシュポットｃ_Ａによる粘性減衰定数の差にほぼ等しい。また、模型実験におけるダッシュポットｃ_Ａとｃ_Ｂの設置数は等しいことから、ダッシュポットに関する提案の水平面配置は、従来の鉛直面配置に比べて、効率的にせん断構造体の減衰を増加させられると考えられる。In Figure 28, the difference between the attenuation constant of System-DFR and System-FR is about 5%, which is the attenuation increased by horizontal arrangement of the dashpot _{c B.} Although the ratio of the viscous damping coefficient of the dashpot _{c A} dashpot _{c B} and System-FR of System-DFR is tau = 0.223, increasing the attenuation constant

The ratio is about 13. Which is approximately equal to the difference between the viscous damping constant by dashpot c _B and dashpot c _A shown in FIG. Moreover, since the number of installed dashpots c _A and c _B in the model experiment is the same, the proposed horizontal plane arrangement for the dashpot can increase the attenuation of the shear structure more efficiently than the conventional vertical plane arrangement. it is conceivable that.

(5) Shaking table shaking experiment focusing on natural vibration mode FIG. 29, FIG. 30 and FIG. 31 show sinusoidal shaking by shaking table for each of the vibration systems of System-DFR, System-FR and System-F, respectively. The first-order and second-order natural vibration modes obtained by measuring the steady-state vibration of the time vibration model are compared with the eigenvectors of the non-damped system shown in Table 4. Since these three vibration systems are non-proportional damped vibration systems, in addition to the shape of the vibration mode represented by the amplitude a _i of the beam, a phase shift based on the movement of the vibration table is also shown. A positive angle represents a phase lag and a negative angle represents a phase advance. During sine wave excitation by shaking table

  Comparing the shapes of the primary eigenmotion modes, all vibration systems agree well with the theoretical values. Since the eigenvectors in Table 4 are non-damped vibration systems, it is theoretically considered that System-F without the influence of the viscous damping device B and the roller is close to the theoretical values shown in Table 4, but the experimental results The difference from the theoretical value increased in the order of System-DFR, System-FR, and System-F. Comparing the phases of the primary natural vibration mode, the phase lag was 65 to 80 ° for System-DFR, 57 to 70 ° for System-FR, and 169 to 175 ° for System-F.

Comparing the amplitudes of the secondary natural vibration modes, all the vibration systems almost agree with the theoretical values, but the difference from the theoretical values is large in System-F. The phase of the secondary mode shows a complicated phase shift depending on the position of the beam, and the phase shift tends to increase as the beam approaches the free end, that is, the beam portion on the roller vehicle body, from the fixed end of the structure. However, no clear relationship was found between the difference in the vibration system and the difference in phase shift. The theoretical value of the natural period of the secondary natural vibration mode is T _{FR, 2} = 0.27 sec. It is.

[Summary]
In order to improve the seismic performance of structures such as high-rise buildings where shear deformation is the main, a cantilever shear structure fixed to the lower end and a shear structure supported at the lower end by a horizontally movable support device Bending cantilever shear structure with long-period natural vibration mode coupled at the upper end and horizontal plane arrangement of the viscous damping device that connects the adjacent beams and floors of the two shear structures constituting this horizontally did. Formulate the equation of motion of the proposed bent cantilever shear structure with the viscous damping device in the horizontal plane and the eigenvalue problem of the non-damped system, and theoretically calculate the natural period and shape of the natural vibration mode of the non-damped system and the viscous damping constant. Led to. In addition, these free vibration characteristics are in a small-scale and limited range of experiments, but were specifically verified by vibration experiments using a model. As a result, the following knowledge about the horizontal arrangement of the shear structure and the viscous damping device of the present embodiment was obtained.

(A) The natural period of the primary natural vibration mode of the bent cantilever shear structure is about twice the natural period of the conventional cantilever shear structure with the same lower end fixed.
(B) Due to the horizontal plane arrangement of the viscous damping device, the viscous damping constant of the first natural vibration mode increased about 13 times compared to the conventional vertical plane arrangement of the viscous damping device.
(C) The damping constant of the first-order natural vibration mode by the horizontal arrangement of the viscous damping device confirmed in the model experiment is about 10 to 15% smaller than the viscous damping constant by the diagonal approximation.
(D) When the rolling resistance of the roller is small, the damping caused by this can be evaluated as equivalent viscous damping due to Coulomb friction force.

  In this bending shear structure, the natural vibration mode can be lengthened by changing the support structure of the frame and foundation of the shear structure. However, this is accompanied by an increase in displacement amplitude due to a decrease in horizontal rigidity. The displacement amplitude can be reduced by increasing the damping constant by installing the viscous damping device, and the horizontal arrangement of the proposed viscous damping device can increase the damping constant more efficiently than the conventional vertical plane arrangement.

  Therefore, constructing a structure with high seismic performance by properly incorporating seismic force reduction by long period using the structure of this embodiment and high attenuation using horizontal arrangement of the viscous damping device into the seismic design can do.

The conceptual explanatory drawing of a cantilever shearing structure (System-CS). A vibration model that defines the dynamic properties of a layer. The conceptual explanatory drawing of the bending cantilever shear structure (System-FR) by which the end was supported with the roller. The figure which shows the relationship between the natural period of the non-attenuation system in System-CS and System-FR, and the number n of layers. An example of a non-damped natural vibration mode of System-FR (α = β = 0, n = 10). The figure which shows the relationship between the viscous damping constant and the number of layers n in System-CS and System-FR. The conceptual explanatory drawing of the bending cantilever shear structure (System-DFR) which arrange | positions a dashpot on a horizontal surface. FIG. 5 is an explanatory diagram of the relationship between the viscosity damping constant and the number of layers n (α = β = 0, τ = 1) in System-DFR. The conceptual front explanatory drawing of the earthquake-resistant structure which concerns on a present Example. 9 is a sectional view taken along line II in FIG. 9 (a), a sectional view taken along line II-II in FIG. 9, and a sectional view taken along line III-III in FIG. 9 (c). Plane explanatory drawing (a) of a horizontal movable support apparatus, Side explanatory drawing (b) of the apparatus. Plane explanatory drawing (a) of an attenuation device, Side explanatory drawing (b) of the same device. Plan explanatory drawing (a) of a sliding friction type horizontal movable support apparatus, Side explanatory drawing (b) of the apparatus. Cross-sectional side view (a) of the damping device, bottom view (b) of the device. Plane explanatory drawing (a) of the expansion-contraction apparatus for floors, and sectional side surface explanatory drawing (b) of the same apparatus. Side surface explanatory drawing (a) which looked at the outer side from the inner side of the expansion device for outer walls, and cross-sectional bottom surface explanatory drawing (b) of the same apparatus. External appearance explanatory drawing of a bending cantilever shear structure model (showing the deformation when a horizontal load acts on the free end). Cross-sectional arrangement explanatory drawing of a viscous damping device. The a section expansion explanatory drawing of FIG. Exploded view of the horizontal movable support device. A graph of the dynamic friction coefficient of a roller body. Expansion explanatory drawing of the viscosity damping device A. FIG. Expansion explanatory drawing of the viscosity damping device B. FIG. Basic dimension explanatory drawing of a viscous damping device. The figure which shows the relationship between the horizontal load and horizontal displacement which act on a free end. The figure which shows the relationship between the primary natural period of System-F0, and a viscous damping constant. Comparison of natural periods focusing on dashpots and rollers. Comparison of viscous damping constant focusing on dashpot and roller. System-DFR natural vibration mode. The natural vibration mode of System-FR. System-F natural vibration mode.

Explanation of symbols

ST Seismic structure DFR Bending cantilever shear structure F Fixed end side shear structure R Free end side shear structure L Sliding friction type horizontal movable support device M Horizontal movable support device Na Damping device (viscous damping device)
Nb damping device (oil damper)
FE Floor expansion device WE External wall expansion device A, B Viscous damping device 10 Lower structure 11 Upper structure 12 Fixed end side layer portion 13 Bent portion formation layer 14 Free end side layer portion 15 Column portion 16 Beam portion (or floor portion) )
17 Column 18 Beam (or floor)
19 Beam (or floor)

Claims (6)

The upper structure is supported on the lower structure, and the upper structure is a structure that mainly resists vertical and horizontal loads mainly in a framework structure,
The upper structure is composed of a fixed end side hierarchical portion composed of a plurality of layers in which the lowermost floor on the fixed end side is fixed to the lower structure, and a bent portion forming layer forming the uppermost floor of the fixed end side hierarchical portion. The free end side layer composed of a plurality of layers in which the bent portion forming layer forms the uppermost floor and the lowermost floor which is the free end side is supported by the lower structure so as to be horizontally movable using a horizontal movable support device. And an integral bent cantilever shear structure that is bent upward and protruding upward ,
At least a pair of bent cantilever shear structures are arranged such that the fixed end side layer portion is located outward and the free end side layer portion is located inward, and the free end side layer portions are integrated with each other. earthquake resistance structure, characterized in that the. The bent cantilever shear structure is arranged radially, and the fixed-end side layer portions adjacent in the circumferential direction are integrally connected to form a cylindrical shape surrounding the free-end side layer portion. The earthquake-resistant structure according to claim 1. The earthquake-resistant structure according to claim 1 or 2 , wherein a damping device is interposed between the lowest floor of the free end side layer and the lower structure. Attenuator is interposed between at least one pair of facing layers or between facing cantilever portions (or cantilever floor portions) of the facing layers of the fixed end side layer portion and the free end side layer portion. The earthquake resistant structure according to any one of claims 1 to 3, wherein the fixed end side layer portion and the free end side layer portion are horizontally connected by the damping device . Extending the cantilever part (or cantilever floor part) from the beam part (or floor part) of at least one pair of opposing layers among the opposing layers of the fixed end side layer part and the free end side layer part. The floor extension device is interposed between the opposing cantilever portions (or cantilever floor portions), and the horizontal relative displacement between the fixed end side layer portion and the free end side layer portion by the floor extension device. The earthquake-resistant structure according to any one of claims 1 to 4, wherein a gap that absorbs water is closed in a horizontally stretchable manner. The base frame part to which the side outer wall part or the side outer wall facing the fixed end side layer part and the free end side layer part is attached is extended in the horizontal direction, between the facing side wall parts, between the facing base frame parts, or The outer wall expansion / contraction device is interposed between the opposing side wall and base frame, and the outer wall expansion / contraction device absorbs the horizontal relative displacement between the fixed end side layer portion and the free end side layer portion horizontally. The earthquake-resistant structure according to any one of claims 1 to 5, wherein the earthquake-resistant structure is closed so as to be stretchable in a direction .

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