JP7628829B2 - Linked vibration control structure - Google Patents

Description

The present invention relates to a linked vibration control structure.

A linked vibration-damping structure is known in which two structures that sway differently are connected by a vibration-damping device such as a vibration damper (see, for example, Patent Documents 1-3). Such linked vibration-damping structures are efficient vibration-damping structures that utilize the large deformation difference between the two structures, and are therefore sometimes used in, for example, high-rise apartment buildings and high-rise offices. The linked vibration-damping structure disclosed in Patent Document 1 connects a perimeter building frame installed on the perimeter of the building with a core rod frame that is installed in the space inside the perimeter building frame and has higher rigidity than the perimeter building frame with a vibration damper. For example, an apartment building is installed on the perimeter building frame, and for example, an elevator or a tower parking lot is installed on the core rod frame.

Recently, linked vibration-damping structures that are combined with seismic isolation structures to reduce response acceleration are also known. The linked vibration-damping structure disclosed in Patent Document 2 has a seismic isolation layer at the bottom of the outer building frame to reduce response acceleration. In addition, the linked vibration-damping structure disclosed in Patent Document 3 has a living area with a multi-layered seismic isolation structure supported by sliding bearings every few stories on the outer periphery of the core, which acts as a seismic resistance element, and the core and living area are connected with springs and dampers.

JP 2009-19479 A JP 2010-112013 A JP 2002-213099 A

However, the above linked vibration control structures have many design restrictions because they are constructed by installing a core rod frame or core inside and an outer building frame around it. Furthermore, linked vibration control structures that combine seismic isolation structures to reduce response acceleration have even more restrictions, resulting in a problem of reduced design freedom.

The present invention aims to provide a linked vibration control structure that can reduce response acceleration and increase design freedom.

To achieve the above objective, the linked vibration-damping structure of the present invention has a main structure having multiple layers and an internal space therein, and a secondary structure provided in the internal space, the main structure having a bottom located below the internal space, and the secondary structure being capable of sliding on the bottom.

In the present invention, when a horizontal force acts on a high-rise building due to an earthquake and the inertial force generated in the secondary structure exceeds the static friction force, a relative slip occurs between the primary structure and the secondary structure. This makes it possible to prevent excessive acceleration from occurring in the secondary structure and reduce the response acceleration. The bottom of the primary structure refers to the floors, beams, etc. of the primary structure. In addition, since the structure does not use walls or brace-type dampers that interfere with the architectural floor plan, but instead simply provides a secondary structure that slides on the bottom of the primary structure in the internal space of the primary structure, it allows for greater design freedom compared to conventional linked vibration control structures.

The linked vibration-damping structure according to the present invention may also have a vibration-damping device that connects the main structure and the secondary structure.

With this configuration, the vibration control device comes into action when relative slip occurs between the main structure and the secondary structure, preventing the relative slip displacement from becoming excessive, and the vibration of the secondary structure is transmitted to the main structure, reducing the inter-story deformation, response acceleration, and story shear force of the entire high-rise building.

In addition, in the linked vibration-damping structure according to the present invention, the main structure may have an internal space inside each layer, and the secondary structure may be provided in each of the internal spaces of each layer of the main structure.

This configuration allows the shape of the sub-structure to be designed for each layer, increasing design freedom. Furthermore, by placing sub-structures of different shapes for each layer or by changing the arrangement of the sub-structures, design freedom can be further increased.

In addition, in the linked vibration-damping structure of the present invention, the secondary structure may be a unit having a floor, walls, and a ceiling.

This configuration allows the unitized secondary structure to be installed on the main structure during construction, making construction easier.

In addition, in the linked vibration-damping structure according to the present invention, the main structure may be provided with an outer wall.

This configuration allows the main structure to bear the wind load, while preventing the wind load from acting on the secondary structure. This means that there is no need to consider wind load acting on the secondary structure, and the coefficient of friction when the secondary structure slides over the bottom of the main structure can be reduced.

In addition, in the linked vibration-damping structure according to the present invention, a sliding bearing may be provided between the secondary structure and the bottom, and the secondary structure may be able to slide on the bottom via the sliding bearing.

By adopting this configuration, when relative slippage occurs between the main structure and the secondary structure, the restoring force of the sliding support can reduce the residual displacement.

The present invention makes it possible to reduce response acceleration and increase design freedom.

1 is a vertical cross-sectional view of a linked vibration damping structure according to an embodiment of the present invention. A vertical cross-sectional view of the upper part. FIG. 13 is a diagram illustrating a sub-structure. FIG. 13 is a diagram illustrating another form of secondary structure. FIG. 1 is a diagram showing an analytical model. FIG. 13 is a diagram showing connection elements of an analytical model. 1 is a table showing analysis parameters. 1 is a table showing the friction coefficient and damping coefficient of each model. 1 is a graph showing input earthquake motion. FIG. 1A is a diagram showing the interlayer deformation angle of each layer of the main structure, FIG. 1B is a diagram showing the acceleration of the secondary structure of each layer, and FIG. FIG. 1A is a diagram showing the relative displacement between the primary structure and secondary structure of each layer, FIG. 1B is a diagram showing the residual displacement of the secondary structure of each layer, and FIG. 1C is a diagram showing the maximum story shear force of the primary structure. FIG. FIG. 13 is a diagram showing a tilt-slip restoring force. FIG. 1A is a diagram showing the inter-story deformation angle of each layer of the main structure when inclined sliding bearings are used; FIG. 1B is a diagram showing the acceleration of the secondary structure of each layer when inclined sliding bearings are used; and FIG. 1C is a diagram showing the acceleration of each layer of the main structure when inclined sliding bearings are used. (a) is a diagram showing the relative displacement between the main structure and secondary structure of each story when inclined sliding bearings are used, (b) is a diagram showing the residual displacement of the secondary structure of each story when inclined sliding bearings are used, and (c) is a diagram showing the maximum story shear force of the main structure when inclined sliding bearings are used.

Below, a linked vibration-damping structure according to an embodiment of the present invention will be described with reference to Figures 1 to 15. As shown in Figure 1, a linked vibration-damping structure 1 according to this embodiment is adopted in the high-rise section 12 of a high-rise building 11. The high-rise section 12 of the high-rise building 11 is used as a hotel, and a low-rise section 13 below the high-rise section 12 is used as an office. The high-rise section 12 has multiple floors (storeies). The linked vibration-damping structure 1 has a main structure 2, a secondary structure 3, and a vibration-damping device 4 that connects the main structure 2 and the secondary structure 3.

The main structure 2 is provided throughout the high-rise section 12. As shown in FIG. 2, the main structure 2 has columns 21, beams 22, and a floor 23 (bottom). Inside the main structure 2, a space surrounded by the columns 21, beams 22, and floor 23 (hereinafter referred to as internal space 24) is formed. The columns 21, beams 22, and floor 23 are provided for each floor. The columns 21, beams 22, and floor 23 are provided throughout the high-rise section 12 in a plan view seen from the top-bottom direction.

In FIG. 2, the secondary structure 3 is indicated by dots. The secondary structure 3 has a floor 31, walls 32, and a ceiling 33. The secondary structure 3 is a unit in which the floor 31, walls 32, and ceiling 33 are assembled into a box shape. In this embodiment, multiple secondary structures 3 are provided in each of the internal spaces of each floor. Each of the multiple secondary structures 3 is installed on the floor 23 of the main structure 2, and is configured to be able to slide on the floor 23 of the main structure 2.

The following structure is an example of a structure in which the secondary structure 3 slides on the floor 23 of the primary structure 2. As shown in FIG. 3, the floor 23 of the primary structure 2 is made up of a deck plate 25 supported by beams 22 and a concrete floor slab 26 constructed on the deck plate 25, and the secondary structure 3 installed on the upper surface of the floor slab 26 is capable of sliding on the upper surface 261 (sliding surface) of the floor slab 26. In this case, it is preferable that the coefficient of friction μ between the floor slab 26 and the secondary structure 3 is, for example, about μ = 0.2 to 0.5.

As another example, there is the following structure. As shown in FIG. 4, the floor 23 of the main structure 2 is made of a deck plate 25 supported by a beam 22 and a main structure steel plate 27 such as an embossed steel plate installed on the deck plate 25. The secondary structure 3 has a concrete plate 35 fixed to the lower part by an anchor bolt 38 or the like. A secondary structure steel plate 36 made of stainless steel or iron is provided on the lower surface of the concrete plate 35 as a sliding plate. The secondary structure 3 installed on the upper surface of the main structure steel plate 27 can slide on the upper surface 271 (sliding surface) of the main structure steel plate 27. In this case, it is preferable that a friction reducing material is provided on the main structure steel plate 27 and the secondary structure steel plate 36 to reduce friction between the main structure steel plate 27 and the secondary structure steel plate 36. The friction coefficient μ between the main structure steel plate 27 and the secondary structure steel plate 36 (sliding plate) can be adjusted by the material of the secondary structure steel plate 36. For example, a general friction material with μ = about 0.03 or 0.1 can be applied.

Returning to FIG. 2, the vibration damping device 4 connects the secondary structure 3 to the primary structure 2. Each of the multiple secondary structures 3 is connected to the primary structure 2 by the vibration damping device 4. The vibration damping device 4 is configured to reduce the relative horizontal displacement between the secondary structure 3 and the primary structure 2. The vibration damping device 4 is, for example, an oil damper or a viscoelastic body. When the secondary structure 3 is displaced relative to the primary structure 2, the load of the secondary structure 3 is transmitted to the primary structure 2 via the frictional force between the secondary structure 3 and the primary structure 2 and the vibration damping device 4.

In the linked vibration-damping structure 1 according to the above embodiment, when a horizontal force acts on the high-rise building 11 due to an earthquake and the inertial force generated in the secondary structure 3 exceeds the static friction force between the secondary structure 3 and the floor 23 of the primary structure 2, a relative slip occurs between the primary structure 2 and the secondary structure 3. This relative slip causes the vibration-damping device 4 to act. In addition, the occurrence of the relative slip prevents the secondary structure 3 from experiencing excessive acceleration. Furthermore, the action of the vibration-damping device 4 prevents the relative slip displacement from becoming excessive, and reduces the inertial force of the secondary structure 3 transmitted to the primary structure 2, thereby reducing the inter-story deformation, response acceleration, and story shear force of the entire high-rise building 11. In addition, the linked vibration-damping structure 1 according to the above embodiment does not use walls or brace-type dampers that hinder the architectural floor plan, but is a structure in which the secondary structure 3 that simply slides on the floor 23 of the primary structure 2 is provided in the internal space 24 of the primary structure 2, so that the degree of design freedom can be increased compared to conventional linked vibration-damping structures.

In addition, in the linked vibration-damping structure 1 according to the above embodiment, the main structure 2 has an internal space 24 in each layer, and the secondary structure 3 is installed in each internal space 24 of each layer. This allows the shape of the secondary structure 3 to be designed arbitrarily for each layer, thereby increasing the degree of design freedom. Furthermore, by installing secondary structures 3 of different shapes for each layer or by changing the arrangement of the secondary structures 3, the degree of design freedom can be further increased.

In addition, in the linked vibration-damping structure 1 according to the above embodiment, the secondary structure 3 is a unit having a floor 23, a ceiling 33, and a wall 32. By adopting such a configuration, the secondary structure 3, which is a unit including the interior and auxiliary equipment, can be installed on the main structure 2 during construction, making construction easier and shortening the construction period.

Next, an analysis to verify the vibration control performance of the linked vibration control structure of this embodiment will be described. Assuming a 10-story steel-framed building 11A having a main structure 2 (sometimes written as a main structure) and a secondary structure 3 (sometimes written as a module) as shown in FIG. 5, and a connection element 5 as shown in FIG. 6, the specifications shown in FIG. 7 were set. The connection element 5 is an element that connects the main structure 2 and the secondary structure 3, and has a vibration control device 4 (vibration control damper) and a friction element 51.

The primary natural period of the no-slip model is 1.29 seconds. The input earthquake motion is the original wave observed in Nishihara Village during the 2016 Kumamoto earthquake (maximum input acceleration 771 gal) (Figure 9). The analysis was performed assuming elasticity of the frame, with only the friction elements being nonlinear. Figure 8 shows a list of friction coefficients and damping coefficients for the model studied. For comparison, a no-slip model with rigid connections on all stories was also created. The damping coefficients of the damping elements were set so that the maximum displacement of the vibration control device 4 would be 60 cm or less.

The maximum response values from the analysis are shown in Figures 10 and 11. However, the inter-story drift angle shows the value of the primary structure, the acceleration shows the value of the secondary structure and primary structure, and the residual displacement shows the "displacement of the secondary structure" - "displacement of the primary structure". The following trends can be confirmed.

In the no-slip model, the inter-story drift angle is extremely large, exceeding 1/50, but by adopting the proposed method, it is possible to reduce the inter-story drift angle of the main structure, and in model 2, which has the greatest effect, it is possible to keep the inter-story drift angle within approximately 1/100.
The more layers that cause slippage and the smaller the friction coefficient, the smaller the interlayer deformation angle of the main structure can be.
The acceleration of the secondary structure of a layer that is allowed to slide can be significantly reduced compared to a non-slip model, and even in rigidly connected layers, the acceleration of the secondary structure can be reduced more than the non-slip model by allowing the upper layer to slide.
The maximum residual displacement was about 20 cm. It has been clarified in previous patents (JP Patent Publication No. 2014-201385, Patent No. 6432763, Patent No. 6590210, etc.) that the inclined sliding mechanism is effective in reducing the residual displacement. The effectiveness of the inclined sliding mechanism will be described later.
In both models, the effect of reducing the story shear force of the main structure was large (the story shear force on the first floor was reduced by 36% to 60% compared to when rigidly connected), and the base shear coefficient of Models 1 and 2 was approximately 0.4.

In the following, normal horizontal sliding and inclined sliding are compared for the above model 2 (friction coefficient μ = 0.1 for the 1st to 9th floors). Figure 12 shows the structure of the inclined sliding support 6 (sliding support). The inclined sliding support 6 is composed of an upper shoe 61 with a V-shaped inclined surface 611, a lower shoe 62 with an inverted V-shaped inclined surface 621, a slider 63 that can slide along the upper shoe 61 and the lower shoe 62, and a sliding member 64. The secondary structure slides on the floor 23 (bottom) via the inclined sliding support 6. As shown in Figure 13, the restoring force of the inclined sliding support is the superposition of the restoring force due to friction and the inclined restoring force. In other words, the residual displacement can be reduced by the restoring force due to the inclined sliding support. In the analysis, the inclination angle of the inclined surface was set to θ = 1.5°. The inclined restoring force is W tan θ = 0.026 W, which is 26% of the friction force of 0.1 W. Although the restoring force is much smaller than the frictional force, this restoring force almost completely eliminates the residual displacement. The secondary structure may also be configured to slide on the floor 23 via a sliding support with a spherical sliding surface.

Figures 14 and 15 show the maximum response values from the analysis results in the case of inclined sliding. There is almost no change in the inter-story deformation angle of the primary structure, the acceleration between the secondary structure and the primary structure, the relative displacement between the primary structure and the secondary structure, and the story shear force of the primary structure between normal horizontal sliding and inclined sliding, but the residual displacement was approximately zero with inclined sliding.

The above analysis verifying the vibration control performance shows that the linked vibration control structure of this embodiment is a construction method with a very high vibration control effect, which is also effective in reducing response acceleration, which is difficult to achieve with conventional vibration control structures. With conventional vibration control structures, it is very difficult to achieve a base shear coefficient of 0.4 when waves observed in Nishihara Village during the Kumamoto earthquake are input. This also confirmed the high vibration control effect of the linked vibration control structure of this embodiment.

By using this in conjunction with modular construction technology for secondary structures, it is possible to simultaneously reduce manpower and improve on-site construction efficiency, and it is also easy to accommodate module updates and changes in use after completion.

In addition, since the linked vibration control structure of this embodiment is configured so that the secondary structure slides layer by layer relative to the main structure, it can be applied in a distributed manner throughout a building, and there is no need to install expensive sliding bearings that can withstand large axial forces.
The linked vibration control structure according to this embodiment can reduce the earthquake response (acceleration, displacement, and story shear force) of not only the sliding secondary structure but also the entire building, whether it is applied partially or entirely to the building. It can also be seen that the greater the number of stories to which it is applied, the greater the response reduction effect.
As a countermeasure against residual displacement, which is a problem when applying this to an actual building, a tilted sliding mechanism (tilt sliding bearing) is considered. The linked vibration control structure according to this embodiment can reduce the residual displacement to almost zero while maintaining the vibration control effect by applying a tilted sliding mechanism.
By installing an exterior wall on the main structure, the secondary structure will not be subjected to wind loads, making it possible to reduce the coefficient of sliding friction.

The above describes an embodiment of the linked vibration control structure according to the present invention, but the present invention is not limited to the above embodiment and can be modified as appropriate without departing from the spirit of the invention.

For example, in the above embodiment, the secondary structure is configured to be slidable on the floor 23 of the primary structure 2, but as long as the bottom is located below the internal space 24, it may be configured to be slidable on the beams 22 of the primary structure 2 instead of the floor 23.

In addition, in the above embodiment, multiple secondary structures 3 are provided in the internal space 24. In contrast, one secondary structure 3 may be provided in the internal space 24 of one layer.

In the above embodiment, the secondary structure 3 is a unit having a floor 23, a ceiling 33, and a wall 32. In contrast, the secondary structure 3 may be composed of only the floor 23, or may be composed of the floor 23 and the wall 32. The secondary structure 3 may also be a structure constructed in the internal space 24 without being unitized.

In addition, in the above embodiment, the main structure 2 does not have an outer wall, but it may have one. With this configuration, the main structure 2 receives wind loads, and the wind loads do not act on the secondary structure 3. Therefore, it is not necessary to consider wind loads acting on the secondary structure 3, and the coefficient of friction when the secondary structure 3 slides on the floor 23 of the main structure 2 can be reduced.

In the above embodiment, the secondary structure 3 is provided on each floor of the high-rise section 12. A plurality of secondary structures 3 may be provided on one floor, or only one may be provided. In this embodiment, a plurality of secondary structures 3 are provided on one floor. In this embodiment, a plurality of secondary structures 3 are provided on each floor in the same manner. The secondary structures 3 may be structured across multiple floors, even if the number or shape of the secondary structures 3 installed on each floor is different. Furthermore, there may be floors on which the secondary structures 3 are not installed. The low-rise section 13 may also be configured to have a main structure and secondary structures, similar to the high-rise section 12.

1 Linked vibration-damping structure 2 Main structure 3 Secondary structure 4 Vibration-damping device 6 Inclined sliding bearing (sliding bearing)
22 Beam 23 Floor 23 (bottom)
24 Interior space 31 Floor 32 Wall 33 Ceiling

Claims (4)

A primary structure having a plurality of layers and an internal space therein;
a sub-structure provided in the internal space;
The main structure has a bottom portion located below the internal space,
the sub-structure being slidable on the base;
The primary structure has the internal space within each layer,
The sub-structure is provided in each of the internal spaces of each layer of the main structure,
A linked vibration-damping structure in which the main structure and the secondary structure are connected only by a vibration-damping device . The linked vibration-damping structure of claim 1 , wherein the sub-structure is a unit having a floor, walls and a ceiling. The linked vibration-damping structure according to claim 1 or 2 , wherein the main structure is provided with an outer wall. A sliding bearing is provided between the substructure and the bottom,
The linked vibration-damping structure according to any one of claims 1 to 3 , wherein the secondary structure is slidable on the bottom via the sliding bearing.

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