JP2018009442A - Base-isolated structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a base-isolated structure that has higher base isolation performance and that can cope with a greater seismic ground motion.SOLUTION: A base-isolated structure includes a core part 1 and a building body 2 adjacent to the core part 1. The base-isolated structure comprises: a multilayered base-isolated structure that comprises a foundation base-isolated layer 3 provided in a lower part of at least the building body 2 of the core part 1 and the building body 2, and an intermediate base-isolated layer 4 provided in an intermediate part of the building body 2; and a connected vibration control structure in which the core part 1 and the building body 2 are connected together by a vibration control device 5.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a seismic isolation structure.

  The seismic isolation structure is a system that achieves both the reduction of ground motion input by increasing the natural period and the effective absorption of seismic energy by concentrating deformation in the seismic isolation layer. The seismic isolation structure having a structure is adopted not only for government buildings, hospitals, and base facilities having head office functions, but also for office buildings, apartment houses, school buildings, etc. (for example, Patent Document 1, Patents) Reference 2 and Patent Reference 3).

JP 2009-019479 A Japanese Patent Laid-Open No. 11-241524 JP 2002-266517 A

  On the other hand, triggered by the Tohoku-Pacific Ocean Earthquake, various ground motions are assumed, and it is required to design structures considering ground motions that are larger than before. There is also a need to consider the case of becoming excessive.

  In other words, the social needs for earthquake countermeasures and business continuity have increased dramatically, and seismic isolation / seismic technology has been actively adopted for ordinary buildings. Conventional disaster prevention facilities and skyscrapers in central Tokyo Higher earthquake-resistant structural performance is required.

  However, the seismic isolation structure has the seismic performance of the entire building determined by the seismic isolation layer, so it may be the first way to apply some countermeasures to the seismic isolation layer as a method of increasing seismic resistance. Therefore, measures to increase the seismic isolation clearance directly lead to a reduction in floor space, and there is a great architectural plan sacrifice. In addition, considering the largest earthquake, increasing the base isolation rigidity to suppress the base isolation displacement or installing a large amount of dampers to increase the damping will increase the acceleration of the superstructure and reduce the base isolation effect. Resulting in.

  In view of the above circumstances, an object of the present invention is to provide a seismic isolation structure that has higher performance seismic isolation performance and can cope with larger seismic motion.

  In order to achieve the above object, the present invention provides the following means.

  The seismic isolation structure of the present invention comprises a core part and a building main part adjacent to the core part, and a basic seismic isolation provided at least in the lower part of the building main part of the core part and the building main part. Multi-layer seismic isolation structure comprising a layer and an intermediate seismic isolation layer provided in the middle part of the building main part, and a coupled vibration damping structure in which the core part and the building main part are coupled by a damping device It is characterized by comprising a structure.

  Further, in the base isolation structure of the present invention, the core portion above the intermediate base isolation layer and the building main portion are integrally formed, and the core portion and the building main portion below the intermediate base isolation layer are formed. It is desirable that they are connected by the vibration damping device and the lower part of the core part is a basic seismic isolation layer.

  In the seismic isolation structure of the present invention, the core portion and the building main portion below the intermediate seismic isolation layer are integrally formed, and the core portion and the building main portion above the intermediate seismic isolation layer are formed by the control. You may be connected with the vibration apparatus.

  In the seismic isolation structure of the present invention, the core part and the building main part are erected independently, and the core part and the building main part above the intermediate seismic isolation layer are connected by the damping device. May be.

  The seismic isolation structure of the present invention comprises a core part and an object main part adjacent to the core part, and a basic seismic isolation provided at least in the lower part of the building main part of the core part and the building main part. A multi-layer seismic isolation structure comprising a layer and an intermediate seismic isolation layer provided in an intermediate part of the building main part, and the core part and the building main part above the intermediate seismic isolation layer are integrally formed, And the said seismic isolation layer is provided with the damping device, It is characterized by the above-mentioned.

  Further, in the base isolation structure of the present invention, the specifications of the base isolation layer stiffness k and damping c to be installed in the intermediate base isolation layer and the base base isolation layer are expressed by the following formulas (1) to (4). It is desirable to set so as to satisfy.

Here, the mass above the upper structure than M _A is an intermediate isolation layer, the mass of M _B lower structure, k _1, k ₂ is exemption of each basic isolation layer and the intermediate layer base isolation layer Shinso stiffness, k ₃ is the base isolation layer rigid under the core _wall, c 1, c ₃ is attenuated to be installed in a basic seismic isolation layer and the core lower support portions respectively, c ₂ is not only the intermediate layer base isolation layer In addition, the eigenvector {r ₁ , r ₂ } is a characteristic vector of the mass points of the upper structure and the lower structure that are normalized with the maximum value being 1, including the damping of the joint control that connects the core wall and the lower structure.

  In the seismic isolation structure of the present invention, ultra-long period can be realized by the multi-layer seismic isolation, and the response acceleration can be halved compared to the conventional seismic isolation structure. In addition, an increase in the top acceleration (whipping response) can be suppressed by increasing the rigidity of the upper frame with a rigid core. Furthermore, by effectively concentrating the deformation on the damping member under the core, the damping effect exceeding the simple multi-layer seismic isolation can be exhibited, and the acceleration reduction effect and the displacement suppression effect can be greatly improved.

  Therefore, according to the seismic isolation structure of the present invention, it is possible to have a higher performance seismic isolation performance and cope with a larger earthquake motion.

It is a figure which shows the seismic isolation structure which concerns on 1st Embodiment (and 3rd Embodiment) of this invention, (a) is a longitudinal cross-sectional view, (b) is a plane cross-sectional view (X1-X1 line of (a)) (Arrow view). It is a figure which shows the vibration model used by the time history response analysis. It is a figure which shows the result of the time history response analysis in 1st Embodiment. It is a figure which shows the result of the time history response analysis in 1st Embodiment. It is a figure which shows an example of the displacement-acceleration relationship of the seismic isolation structure which concerns on 1st Embodiment of this invention. It is a figure which shows the seismic isolation structure which concerns on 2nd Embodiment of this invention. It is a figure which shows the vibration model used by the time history response analysis. It is a figure which shows the result of the time history response analysis in 2nd Embodiment. It is a figure which shows the result of the time history response analysis in 2nd Embodiment. It is a figure which shows the result of the time history response analysis in 2nd Embodiment. It is a figure which shows the analysis model of the seismic isolation structure of 3rd Embodiment, and the definition of each item. It is a figure which shows an example of the analysis model of the seismic isolation structure of 3rd Embodiment, and a primary vibration mode. It is a figure which shows the suitable application range of the seismic isolation structure of this invention while showing the relationship between (alpha) and (beta) when (micro | micron | mu) = 1.0. It is a figure which shows the suitable application range of the seismic isolation structure of this invention while showing the relationship of (alpha) and (beta) when (micro | micron | mu) = 0.5. It is a figure which shows (a) the conventional seismic isolation structure used by the analysis, (b) the conventional multilayer seismic isolation structure, and (c) the seismic isolation structure of this invention. It is a figure which shows the analysis result performed on the comparison conditions (1). It is a figure which shows the analysis result performed on the comparison conditions (2). It is a figure which shows the analysis result performed on the comparison conditions (3). It is a figure which shows the pseudo speed response spectrum of an input earthquake motion. It is a figure which shows the analysis result (a)-(e) performed on the comparison conditions (1), and the input acceleration (f) of each input earthquake motion. It is a figure which shows the multi-mass point system analysis model of (a) conventional seismic isolation structure, (b) conventional multi-layer seismic isolation structure, and (c) seismic isolation structure of this invention. It is a figure which shows the design parameters (micro | micron | mu), (alpha), (beta), and (gamma) about the item collected by 2 mass point system. It is a figure which shows an analysis result, and is a figure which shows maximum response acceleration distribution. It is a figure which shows an analysis result, and is a figure which shows the largest interlayer deformation angle distribution. It is a figure which shows an analysis result, and is a figure which shows the deformation amount of a seismic isolation layer.

  Hereinafter, the seismic isolation structure according to the first embodiment of the present invention will be described with reference to FIGS. 1 to 5.

  The seismic isolation structure of the present embodiment has a multi-layer seismic isolation structure in which a rigid core is passed through a multi-layer seismic isolation building having a plurality of seismic isolation layers and connected to each other by a seismic control device. While achieving acceleration reduction that is impossible with a base-isolated structure, the joint control system installed at the bottom of the clearance and the core exhibits a seismic control effect that is not possible with simple multi-layer base isolation, and achieves both displacement control. It is configured as follows.

  Specifically, the seismic isolation structure A of the present embodiment is a seismic isolation building, and as shown in FIG. 1, in a plan view shape having a core wall at the center of the building, the vertical direction from the bottom layer to the top layer A rigid core portion (building central portion) 1 continuously extended to the main portion of the building (adjacent to the core portion 1 and surrounding the core portion 1 to form the surroundings of the building) Part) 2. In addition, in FIG. 1, although the core part 1 is made into the center core, of course, you may be a structure provided with the eccentric core and the both-ends core.

  The core part 1 and the building main part 2 are each provided with a basic seismic isolation layer 3 at the lower part, and the base seismic isolation layer 3 is provided with an optional seismic isolation support (isolation device) and an attenuation device. For example, seismic isolation bearings may be laminated rubber, sliding bearings, linear sliders or a combination of several, and damping devices may be oil dampers, lead dampers (including LRBs contained in laminated rubber), steel dampers, friction dampers. Any one or a plurality of these can be used in combination.

  Further, the seismic isolation structure A of the present embodiment includes an intermediate seismic isolation layer 4 at a predetermined level, and the core part 1 and the main building part 2 are integrally formed above the intermediate seismic isolation layer 4, so The lower layer from the seismic layer 4 is formed so that the building main part 2 provides a predetermined space between the core part 1 and stands independently. The middle seismic isolation layer 4 is provided with an optional seismic isolation bearing (base isolation device) in the same way as the base isolation layer 3 and is supported by the main building 2 in the upper layer with the middle seismic isolation layer 4 as a boundary. Has been.

  In addition, the building main part 2 and the core part 1 which are erected independently from each other below the intermediate seismic isolation layer 4 are connected via a vibration damping device (connection damper, damping element) 5. In addition, a spring element and a damping element may be applied as the vibration damping device 5. In this case, the core part 1 and the building main part 2 (mutually between the core part 1 and the building main part 2) are used as TMD weight elements. It also becomes possible to make it function.

  And in the seismic isolation structure A of this embodiment, the multi-layer seismic isolation structure having the basic seismic isolation layer 3 and the intermediate seismic isolation layer 4 can realize an extremely long natural period. .

  In addition, a rigid core part 1 is penetrated through all layers of the building to form a structural and functional mandrel, and the main building part 2 (base frame) below the intermediate seismic isolation layer 4 is connected to the core part 1 By adopting a vibration control structure, response control can be performed efficiently.

  Furthermore, by supporting the core portion 1 with the seismic isolation layer 3, it is possible to positively deform the damping device installed in the seismic isolation layer 3 at the time of an earthquake and to improve energy absorption efficiency. In addition, the position of the intermediate seismic isolation layer 4 can be freely determined from the viewpoint of architectural planning such as the boundary of use.

  Moreover, in the seismic isolation structure A of this embodiment, by configuring as described above, seismic isolation performance in a region other than the target region for conventional cored seismic isolation and multilayer seismic isolation in the relationship between acceleration and displacement. It becomes possible to bear.

  Here, in order to verify the effect of the seismic isolation structure A of this embodiment, examination (simulation) by time history response analysis was performed using the vibration model of the seismic isolation structure A of this embodiment. For comparison, response analysis was also carried out for a multi-layer base isolation structure and an intermediate-layer base isolation model with a core.

First, the analysis model was set as follows.
FIG. 2A is a multi-layer seismic isolation model having two seismic isolation layers in the building, and FIG. 2B is a model simulating an intermediate layer seismic isolation structure having a core. FIG.2 (c) is the seismic isolation structure A of this embodiment, and is the multilayer seismic isolation model which has a core.

  The main part of the building is a 30-mass point shear model, and the core part is a 30-mass bending shear model. The main part of the building uses linear characteristics assuming an S structure except for the seismic isolation layer. The core part uses linear characteristics of bending and shearing assuming RC construction.

  Each model has a base isolation layer and an intermediate isolation layer. The models shown in Fig. 2 (b) and Fig. 2 (c) use rigid beams for the main building and the core above the intermediate isolation layer. It is tight. Moreover, in the model of the seismic isolation structure A of this embodiment of FIG.2 (c), the building main part and core part of a layer lower than an intermediate seismic isolation layer are connected with the damper.

Table 1 shows the specifications of each vibration model used in the above analysis.
As shown in Table 1, the base-isolated base isolation layer of Fig. 2 (b) distributes the base isolation base stiffness and damping of the multi-layer base isolation according to the mass ratio of the main building and the core. . The cored multi-layer seismic isolation dampers in Fig. 2 (c) were installed at 1.0E + 07kN / (m / s) on the 1st to 4th layers above the base seismic isolation layer. In addition, the total amount of dampers for cored multi-layer seismic isolation is the same as the total amount of dampers for multi-layer base isolation including connected dampers.

  And as shown in Table 1, first, the natural period with seismic isolation is compared between the three models. The cored seismic isolation model is 5.05 seconds, which is equivalent to the natural period of a general seismic isolated building. However, the multi-layer seismic isolation and the multi-layer seismic isolation with a core are 7.14 seconds and 6.08 seconds, respectively, which are longer than general seismic isolation buildings. confirmed.

Next, for the time history response analysis, EL CENTRO, notification KOBE, and OS2 were used as input earthquake motions.
EL CENTRO has a large acceleration response in a period band of 1 second or less, and the notification KOBE is characterized by a flat velocity response spectrum from 1 second or less to a long period region. OS2 is characterized by a large velocity response spectrum in a long period of 5 to 8 seconds.

FIG. 3 shows the maximum value distribution of acceleration, displacement, and interlayer deformation angle of the building main part and the core part as a result of time history response analysis when EL CENTRO is input earthquake motion.
In addition, when the notification KOBE and OS2 are input seismic motions, the same tendency is shown.

  First, when evaluating acceleration response, the core-based seismic isolation is higher than the middle seismic isolation layer of the main part of the building, and the core part has the same acceleration reduction effect as the general seismic isolation structure. Because it is earthquake resistant, the response acceleration cannot be reduced.

  The main part of the building with multi-layer seismic isolation and core multi-layer seismic isolation has a large acceleration reduction effect over all layers due to the ultra-long period by multi-layer seismic isolation.

  However, multi-layer seismic isolation tends to amplify the acceleration immediately below the middle seismic isolation layer and the top of the building. In the case of EL CENTRO (and notification KOBE) input, there is a layer exceeding 100 Gal, Acceleration amplification directly below the middle seismic isolation layer and the top of the building can be suppressed by the combined vibration control and the core effect, and approximately 100 Gal or less can be realized in all layers.

  Next, when evaluating the response displacement, the base and intermediate isolation layer displacements of the cored multi-layer seismic isolation are suppressed to be smaller than each seismic isolation layer displacement of the multi-layer seismic isolation, and in OS2 with the largest response displacement It was confirmed that the maximum displacement at the top was reduced by 30% or more with respect to multi-layer seismic isolation. Since the total amount of damper in the multi-layer seismic isolation model and the core multi-layer seismic isolation model is the same, the multi-layer seismic isolation with core more effectively exhibits the damping effect of the damper, reducing acceleration and displacement control. It was confirmed that it contributed to coexistence.

  FIG. 4 shows the maximum distribution of displacement between the main building and the core building in each analysis case of the core-isolated and multi-layered base-isolated. In any case, the inter-building displacement is reduced with the multi-layer seismic isolation with core. Since the displacement is 130 mm to 350 mm, it is only necessary to secure about 400 mm as the stroke of the connecting damper, which can be handled by an existing seismic isolation damper.

  As described above, in the seismic isolation structure A of the present embodiment, it is possible to realize an effective structure that can achieve both a significant reduction in acceleration response due to the multi-layer seismic isolation and a displacement control of the seismic isolation layer due to the joint seismic control. Proven.

  Therefore, in the seismic isolation structure A of the present embodiment, ultra-long period can be realized by the multi-layer seismic isolation, and the response acceleration can be halved compared with the conventional seismic isolation structure. Further, the increase in the top acceleration (whipping response) can be suppressed by increasing the rigidity of the upper frame by the rigid core portion 1. In addition, the combined damping that connects the core part 1 and the building main part 2 below the intermediate seismic isolation layer 4 with a damping device realizes both acceleration reduction effect and displacement suppression effect that exceed simple multi-layer isolation. It becomes possible.

  Moreover, in the seismic isolation structure A of this embodiment, the damper of the lower part of a core can absorb the earthquake energy of a high floor, and can reduce the displacement of the whole structure efficiently. Since the deformation of the base isolation layer is dispersed by the multi-layer base isolation, the maximum response displacement of the base isolation layer can be reduced as compared with the conventional base isolation structure. Since the seismic isolation layer displacement can be suppressed, the seismic margin is improved and it is possible to cope with the largest design seismic motion.

  Furthermore, in the seismic isolation structure A of the present embodiment, the installation locations of the dampers can be planned at the base seismic isolation layer 3, the intermediate seismic isolation layer 4, the connection part (connection damper part), and the lower part of the core. It is possible to combine the number of seismic control devices. For this reason, there are many options as a seismic control system, and tuning according to required performance becomes possible. That is, it becomes possible for the designer to select and judge as appropriate, such as emphasizing acceleration reduction, emphasizing displacement control, and a balance between the two.

  In addition, there are many places where dampers can be installed, and as a result, the damping performance of the entire structure can be greatly improved compared to conventional seismic isolation structures and multi-layer seismic isolation structures.

  Furthermore, in the seismic isolation structure A of the present embodiment, the seismic force acting on the room of the main part 2 of the building is reduced by the multi-layer seismic isolation, and a structure in which the core part 1 bears most of the horizontal force is realized. it can. For this reason, it becomes possible to improve the degree of freedom of the architectural plan by slimming the pillars and beams and by extending the span.

  In addition, since the core portion 1 penetrates the building in the height direction while being multi-layer seismic isolation, it is possible to plan that the vertical shafts of elevators, equipment, etc. are not divided by the seismic isolation layer. Furthermore, since the core part 1 is united with the main building part 2 where the room is located on the higher floor, it is possible to plan that the rentable ratio of the reference floor does not decrease due to the connected vibration control.

  Moreover, by adjusting the rigidity balance of each seismic isolation layer and controlling the deformation, the seismic isolation clearance required for the outer periphery of the building is halved compared to general seismic isolation, and the site can be used effectively.

  Moreover, in the seismic isolation structure A of this embodiment, even if the seismic motion exceeding assumption is input and the displacement of the seismic isolation layer increases, the core structure 1 that penetrates the building functions as a core rod, so that the upper structure And the basement structure does not fall off each other. As a result, a reliable and safe multi-layer seismic isolation structure can be realized.

  Therefore, according to the seismic isolation structure A of the present embodiment, it is possible to provide a higher performance seismic isolation performance and cope with a larger earthquake motion.

  Further, according to the seismic isolation structure A of the present embodiment, as shown in FIG. 5, a conventional cored seismic isolation (see FIG. 2 (b)), a conventional multi-layer seismic isolation (see FIG. 2 (a)). It is possible to provide seismic isolation performance in a displacement-acceleration region different from).

  As mentioned above, although 1st Embodiment of the seismic isolation structure which concerns on this invention was described, this invention is not limited to said 1st Embodiment, It can change suitably in the range which does not deviate from the meaning.

  For example, as in the present embodiment, an intermediate seismic isolation layer 4 is provided at a predetermined level, the upper layer above the intermediate seismic isolation layer 4 is integrally formed with the core part 1 and the main building part 2, and the intermediate seismic isolation layer 4 extends to the lower layer. When a predetermined space is provided between the building main part 2 and the core part 1, the building main part 2 and the core part 1 lower than the intermediate seismic isolation layer 4 are not necessarily connected as in the present embodiment. (Damper, damping element) 5 may not be connected. In this case, for example, by providing a seismic isolation device 5 in the intermediate seismic isolation layer 4 together with an optional seismic isolation support (seismic isolation device) in the intermediate seismic isolation layer 4 (dampers are concentrated on the intermediate seismic isolation layer 4 Therefore, it is possible to obtain the same effect as the present embodiment.

  Next, with reference to FIGS. 6 to 10, a seismic isolation structure according to a second embodiment of the present invention will be described. In the present embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  The seismic isolation structure B of the present embodiment is a seismic isolation building, and as shown in FIG. 6A, the independent core part (the central part of the building, one seismic isolation structure) 1 and the core part 1. The building main part (the other seismic isolation structure) 2 is provided so as to be adjacent to the core part 1 and surround the core part 1. In addition, although the core part 1 is made into the center core, of course, even if it is a structure provided with the eccentric core and the both-ends core, it does not matter.

  Moreover, the building main part 2 is provided with a base seismic isolation layer 3 in the lower part, and the base seismic isolation layer 3 is provided with any seismic isolation bearing (base isolation device) and a damping device. As in the first embodiment, for example, as a seismic isolation bearing, laminated rubber, a sliding bearing, a linear slider, or a combination of a plurality of sliders are used, and as a damping device, an oil damper, a lead damper (including an LRB included in the laminated rubber) ), Steel damper, friction damper, or a combination of two or more.

  Furthermore, an intermediate seismic isolation layer 4 is provided at a predetermined level in the building main part 2 standing independently of the core part 1. The middle seismic isolation layer 4 is provided with an optional seismic isolation bearing (seismic isolation device) in the same way as the basic seismic isolation layer 3, and the upper part of the building is supported by the seismic isolation bearing. ing.

  Furthermore, the building main part 2 and the core part 1 which are erected independently of each other in an upper layer than the intermediate seismic isolation layer 4 are connected via a vibration damping device (connection damper, damping element) 5. In addition, a spring element and a damping element may be applied as the vibration damping device 5. In this case, the core part 1 and the building main part 2 (mutually between the core part 1 and the building main part 2) are used as TMD weight elements. It also becomes possible to make it function.

  In the seismic isolation structure B of the present embodiment, as shown in FIG. 6 (b), the core portion 1 and the main building portion 2 below the intermediate seismic isolation layer 4 are integrally formed, and the core portion 1 The base seismic isolation layer 3 may be provided at the lower part of the building main part 2.

  In the seismic isolation structure B of the present embodiment configured as described above, it is possible to reduce the response displacement while suppressing an increase in the response acceleration of the seismic isolation layer of the main part 2 of the building as compared to a normal base isolation building. It becomes possible.

  That is, in the seismic isolation structure B of the present embodiment, the building main part 2 and the core part 1 having different vibration characteristics are provided by providing seismic isolation layers at the foundation and middle of the building to form a multi-layer seismic isolation structure. By providing the connected seismic control structure to be connected, it is possible to effectively reduce the earthquake response of both the core part 1 and the building main part 2.

  In addition, when the core part 1 is made into an earthquake-resistant structure as shown in FIG. 6A, the building main part 2 is provided with seismic isolation layers at the foundation part and the middle part of the building, and the core part 1 and the building main part 2 are arbitrarily connected. What is necessary is just to connect with a damper in a height position.

  On the other hand, when the core part 1 has a basic seismic isolation structure as shown in FIG. 6 (b), the building main part 2 has a seismic isolation structure supported by the intermediate seismic isolation layer 4 on the base frame of the core part 1, and the core Part 1 and building main part 2 are connected by damper 5. At this time, the connecting position in the height direction of the damper 5 is an arbitrary position above the intermediate seismic isolation layer 4.

  In order to effectively reduce the acceleration response, it is desirable to provide the intermediate seismic isolation layer 4 from the middle layer to the lower layer of the building.

  Here, in order to verify the effect of the seismic isolation structure A of this embodiment, examination (simulation) by time history response analysis is performed using the vibration model of the seismic isolation structure B of this embodiment shown in FIG. It was.

First, the analysis model was set as follows.
As shown in FIG. 7, the building main part 2 is a 30-mass point shear model, and the core part 1 is a 30-mass point bending shear model. The main part 2 of the building is a multi-layer seismic isolation with a base isolation layer in the lowest layer and the seventh layer, and other than the base isolation layer, it is assumed to have linear characteristics assuming an S structure.

  The core portion 1 is a foundation-fixed seismic structure, and each layer is assumed to have linear characteristics of bending and shearing assuming RC construction.

Table 2 shows the specifications of the vibration model used for the analysis.
The connecting damper 5 was installed directly above the middle seismic isolation layer 4. Moreover, the connection damper 5 was installed in the upper layer of the middle seismic isolation layer 4 and the 20th floor. The connecting damper 5 was a linear oil damper having a damping coefficient of 1000 kN / (m / s) per unit.

  For the time history response analysis, input ground motion with a substantially flat velocity response spectrum from less than 1 second to a long period region was used.

FIG. 8 shows the maximum response value distribution when the connecting damper 5 is installed immediately above the base isolation layer.
In the figure, “No connection” means a case where there is no damper 5 connecting the main building part 2 and the core part 1, “OD connection (10 units)” means a case where 10 oil dampers 5 are connected, and “OD connection (20 Stand) ”is a case where 20 oil dampers 5 are connected.

  First, in the case of “no connection”, the acceleration of the main part 2 of the building was reduced to 100 Gal or less due to the effect of the multi-layer seismic isolation, and the acceleration reduction effect exceeding the conventional seismic isolation structure was confirmed. The maximum displacements of the base and middle seismic isolation layers were about 30 to 40 cm each, and the size was not so different from the conventional base isolation structure.

  Furthermore, when the building main part 2 and the core part 1 are connected by the damper 5 as in “OD connection (10 units)” and “OD connection (20 units)”, the acceleration response is hardly increased, and the basic and intermediate portions are not increased. It was confirmed that the seismic isolation layer displacement was greatly reduced. This means that the margin of the seismic isolation layer has greatly improved. Moreover, each response value is reduced by connecting the core part 1 with the damper 5.

FIG. 9 shows the maximum response value distribution when the connecting damper 5 is installed immediately above the base isolation layer and the 20th floor.
In the figure, “No connection” is the case where there is no damper 5 connecting the main building part 2 and the core part 1, and “OD connection (10 units + 10 units)” is 10 units directly above the middle seismic isolation layer and 10 units on the 20th floor. The case is connected by a total of 20 oil dampers 5.

  As in FIG. 8, it was confirmed that the displacement of the base isolation layer at the foundation and the middle part can be suppressed without substantially increasing the acceleration by installing the connecting damper 5, and the response reduction effect of the core part 1 was also confirmed. The relative displacement of the building top with respect to the ground surface was halved in both the main building part 2 and the core part 1, and a high deformation suppressing effect was confirmed. In addition, “OD connection (10 units + 10 units)” had a response reduction effect almost equivalent to the case of “OD connection (20 units)” shown in FIG.

  Thereby, the installation position in the height direction of the connecting damper 5 can be arbitrarily set, and if the amount of the damper is the same amount, the same response reduction effect can be obtained regardless of the installation position. It was confirmed that they can be arranged arbitrarily.

  FIG. 10 shows the maximum value distribution of displacement between the building main part 2 and the core part 1 in the analysis cases of FIGS. 8 and 9. The displacement between buildings just above the middle seismic isolation layer in FIG. 10 (a) was about 40 cm, and the displacement above the middle seismic isolation layer in FIG. 10 (b) was also about 40 cm. Thereby, the stroke of the damper 5 is about 40 cm, and it was confirmed that the existing seismic isolation damper can sufficiently cope with it.

  From the above, it was proved that the seismic isolation structure of the present embodiment can achieve both a significant reduction in acceleration response due to the multi-layer seismic isolation and displacement control of the seismic isolation layer due to coupled seismic control.

  Therefore, in the seismic isolation structure B of the present embodiment, the ultra-long period can be realized by the multi-layer seismic isolation, and the response acceleration can be halved compared to the conventional seismic isolation structure. Moreover, the response control of a high-rise part is possible by the joint vibration control with the core part 1, and even when the rigidity of the building main part 2 is small, a whip swing response can be reduced.

  Moreover, since the deformation of the base isolation layer is dispersed by the multi-layer base isolation, it is possible to reduce the maximum response displacement of the base isolation layer compared to the conventional base isolation. Furthermore, the deformation of the base isolation layer can be greatly reduced by suppressing the response acceleration by the coupled vibration control.

  In addition, the installation location of the damper 5 can be planned in three locations: the base seismic isolation layer 3, the intermediate seismic isolation layer 4, and the connecting part, and any seismic control device can be combined, so it is an option as a seismic control system There are many.

  There are many places where the damper 5 can be installed, and the damping performance of the entire structure can be greatly improved as compared with conventional seismic isolation structures and multi-layer seismic isolation structures.

  Furthermore, the building main part 2 has a seismic force reduced by the multi-layer seismic isolation, and the horizontal force can be borne by the core part 1 through the coupled vibration control. For this reason, it becomes possible to improve the degree of freedom of the architectural plan by slimming the pillars and beams and by extending the span.

  In addition, since the core portion 1 penetrates the building in the height direction while being multi-layer seismic isolation, it is possible to plan that the vertical shafts of elevators, equipment, etc. are not divided by the seismic isolation layer.

  It is possible to plan to keep the seismic isolation clearance small by controlling the seismic isolation layer displacement by connecting seismic control.

  Even if the seismic ground motion exceeds the expected value and the displacement of the seismic isolation layer increases, the core part 1 that penetrates the building functions as a stopper and the upper structure does not fall off, making it highly reliable and safe. A multi-layer seismic isolation structure can be realized.

  Therefore, according to the seismic isolation structure B of the present embodiment, it is possible to have a higher performance seismic isolation performance and cope with a larger earthquake motion.

  As mentioned above, although 2nd Embodiment of the seismic isolation structure which concerns on this invention was described, this invention is not limited to said 2nd Embodiment, The range which does not deviate from the meaning including 1st Embodiment. It can be changed as appropriate.

  Next, with reference to FIG. 1, FIG. 11 to FIG. 25, the seismic isolation structure which concerns on 3rd Embodiment of this invention is demonstrated. In the present embodiment, the same components as those in the first and second embodiments are denoted by the same reference numerals, and detailed description thereof is omitted.

  First, in this embodiment, i) it is possible to realize a significant acceleration reduction that cannot be achieved by the conventional seismic isolation structure while keeping the seismic isolation layer displacement equal to that of the conventional seismic isolation structure, and ii) a plurality of Each type of seismic isolation to achieve a significant displacement suppression of the seismic isolation layer, which could not be achieved with the conventional multi-layer seismic isolation, while having the same effect of reducing the acceleration as a multi-layer seismic isolation structure with multiple seismic isolation layers The application range of the optimal seismic isolation specifications, such as seismic layer rigidity and the amount of attenuation to be installed, will be explained.

  Specifically, in this embodiment, the seismic isolation structure A (the seismic isolation structure A similar to the first embodiment) shown in FIGS. 1A and 1B will be described as an example. In addition, in FIG. 1, although the core part 1 is made into the center core, of course, you may be a structure provided with the eccentric core and the both-ends core.

  And the method of setting the application range of the seismic isolation specification which can implement | achieve the matter of following 1) -5) with respect to the seismic isolation structure A shown in FIG. 1 is demonstrated below.

(1) A multi-layer seismic isolation structure with a base isolation and an intermediate isolation will be used to achieve an extremely long natural period.
(2) A rigid core wall is penetrated throughout the building to form a structural and functional mandrel (in a general multi-layer seismic isolation, the core wall is divided by an intermediate seismic isolation layer).
(3) The response control will be performed efficiently by connecting the foundation frame to the core wall.
(4) Under the core wall is also supported by the seismic isolation layer, which is actively deformed to improve energy absorption efficiency.
(5) The location of the middle-layer seismic isolation can be determined from the architectural planning point of view, such as boundary of use.

Here, the vibration model of FIG. 1 can be expressed as shown in FIG.
Mass M _A is above the upper structure than the intermediate isolation layer 4, the mass of M _B lower structure, Men k _1, k ₂ each basic isolation layer 3 and the intermediate layer base isolation layer 4 Shinso rigidity, k ₃ is a seismic isolation layer rigidity under the core wall. Since the rigidity of the general part is orders of magnitude greater than the rigidity of the seismic isolation layer 3, the upper and lower layers are rigid with an infinite layer rigidity (however, the examination of multi-mass systems including building rigidity will be described later) To do). Further, c ₁ and c ₃ are attenuations installed in the base seismic isolation layer 3 and the core lower support part, respectively. c ₂ includes not only the intermediate seismic isolation layer 4 but also the damping of the connected seismic control that connects the core wall and the substructure. The eigenvectors {r ₁ , r ₂ } in FIG. 11 are eigenvectors of the mass points A and B that are standardized with the maximum value being 1.

  With respect to these, the application range in which the response reduction effect can be expected is shown below.

  And in this embodiment, the application range of the specification installed in the seismic isolation layer 3 is set like the following formula | equation (5)-Formula (8).

In this embodiment, the specifications of the bearings and dampers (k ₁ , k ₂ , k ₃ and c ₁ , c ₂₎ installed in the seismic isolation layers 3, 4 with respect to the multi-layer seismic isolation structure A , C ₃ specifications), that is, an application range in which a response reduction effect can be expected is set as shown in the following equations (5), (6), (7), and (8). Here, the unit of each specification is mass M (t), rigidity k (kt / m), and attenuation c (kN / cm / s).

  Next, in order to derive the optimum range, first, equations (10) and (11) are derived from the eigenvalue problem (equation (9)) at the time of non-damped vibration.

  Then, Expression (12) and Expression (13) are derived using Expression (10), Expression (11), α, and β.

  Next, when Expression (14) is obtained from Expression (12) and Expression (13), and α is further used, Expression (14) becomes Expression (15).

Here, the example of the primary vibration mode of the seismic isolation structure A of this embodiment is shown in FIG.
FIG. 12B shows a vibration mode when the upper and lower seismic isolation layers 3 and 4 are aligned, and FIG. 12C shows the lower seismic isolation layer 3 by relatively softening the rigidity. This is a vibration mode when the displacement of the seismic isolation layer 3 is increased.

  From the prior analysis, since the seismic isolation structure A of the present embodiment is provided with the seismic isolation layer 3 under the core portion 1, the rigidity of the seismic isolation layer 3 is made relatively soft to add damping, By absorbing energy at the part, it is possible to enhance the effect of reducing the building response without increasing the acceleration response value of the lower structure below the intermediate seismic isolation layer 4.

  From this preliminary analysis result, it is desirable that the upper limit value of γ is ideally 2.5 to 3.0 or less, but 1.0 <γ <in consideration of the variation of the seismic isolation device (for example, laminated rubber). The applicable range was set to 4.0.

In the actual design, 1) the primary natural period of the building is determined, and 2) the mass ratio (μ) of the upper layer portion and the lower layer portion is determined in the building plan. That is, ω ₁ and μ are often known.

  Here, FIG. 13 and FIG. 14 show the results of obtaining the relationship between α and β within the range of the upper and lower limits of γ set by prior analysis by substituting known μ into the equation (14). FIG. 13 shows the case where μ = 1.0, and FIG. 14 shows the case where μ = 0.5. Note that no constraint is set for μ.

The range shown in FIG. 13 is an application range in which a response reduction effect can be expected, and is a rigidity ratio of k ₁ , k ₂ , and k ₃ to be obtained.

Next, the application range regarding the viscous damping amount of c _{1 to} c ₃ is shown.
The upper limit values of c ₁ and c ₂ are less than 100% so as not to be overdamped with respect to the entire second-order natural period as stiffness-proportional damping. Further, the lower limit value of c ₁ is set to 5% or more with respect to the primary natural period based on the preliminary analysis result. c ₂ because the response effect of reducing the base-isolated structure A of this embodiment, even if the attenuation zero in the pre-analysis was confirmed, was 0 or more.

This can be summarized by Expression (16), and Expression (17) can be obtained from Expression (16). _Here, k1 _{h 2} is the second order decay constant.

Similarly, equation (19) is obtained from equation (18). _Here, k2 _{h 2} is the second order decay constant.

For c _3, a condition necessarily adding attenuation, the equation (20).

  Note that the above range is an application range of viscous damping, and a hysteresis damper such as a friction damper or LRB can be added without a range.

  Next, the result of confirming the response reduction effect in the range of the above specifications will be described.

<Response magnification curve>
First, FIG. 15 (a) is a conventional base-isolated structure, FIG. 15 (b) is a conventional simple multi-layer base-isolated structure, and FIG. 15 (c) is a schematic diagram of the base-isolated structure according to the present invention. A frame structure is shown.

  Among these, for the conventional multi-layer seismic isolation structure and the seismic isolation structure according to the present invention, the response magnification of each displacement of the mass point A and the mass point B under the following comparison conditions (1) to (3) The curve and the response magnification curve of acceleration were compared (FIGS. 16 to 18).

Table 3 shows the specifications of the analysis model set.
At this time, specification of the multi-layer base isolation (1) to (3) determines the stiffness k such that _{ρ (= T A / T B} ) = 1.0, the attenuation c conferred rigid proportional.

On the other hand, examples (1) to (3) of the seismic isolation structure according to the present invention give the rigidity k with the rigidity ratio α satisfying the eigenvector ratio γ satisfying 1.0 <γ <4.0, and the damping c is also applicable. the sum of the damping coefficient on which to satisfy is set to be equal to that of the multi-layer base isolation and sets the attenuation of c _3.

Comparison condition (1): Period (T) = 7 seconds Mass ratio (μ) = 1.0
Comparison condition (2): Period (T) = 7 seconds Mass ratio (μ) = 0.5
Comparison condition (3): Period (T) = 6 seconds Mass ratio (μ) = 1.0

  From FIG. 16 to FIG. 18, the example of the seismic isolation structure of the present invention can greatly reduce the response displacement and response acceleration of the mass point A under any comparison condition, and further the peak value of the displacement and acceleration of the mass point B. It can be seen that That is, according to the seismic isolation structure of the present invention, both displacement and acceleration can be reduced in both the upper layer and the lower layer than in the conventional multi-layer seismic isolation structure shown in FIG.

<Earthquake response analysis>
Next, the result of performing time history response analysis on the above-mentioned comparison condition (1) for the two mass point system model shown in FIG. 12 is shown.

  Input seismic motion is 3 waves of observation waves (El Centro NS, Taft EW, Hachinohe EW) normalized to Lv2, 3 waves of notification waves (Kobe NS phase, Kanto EW phase, random phase), and Nankai Trough earthquake motion (OS1) (See FIG. 20 (f)). These pseudo speed response spectra (h = 5%) are shown in FIG.

  And as the analysis result shown in Drawing 20 (a)-Drawing 20 (e), the response acceleration of mass A is compared with example (1) of the conventional multilayer seismic isolation structure of example (1) of the present invention. Are equal or less in any earthquake motion. Similarly, the response acceleration of the mass point B is also reduced.

  About the interlaminar deformation of the mass point A, the reduction effect of the example (1) of the present invention is remarkably exhibited, and is approximately halved compared with the conventional example (1) of the multi-layer seismic isolation. The interlaminar deformation of the mass B is almost the same. Therefore, the effectiveness of the example (1) of the present invention can also be confirmed in the time history response analysis.

Next, the results of studying the equivalent shear type multi-mass system analysis model will be described.
Here, the conventional seismic isolation structure shown in FIG. 21 (a), the conventional multi-layer seismic isolation structure shown in FIG. 21 (b), and the seismic isolation structure of the present invention shown in FIG. 21 (c). For three cases of objects, each was modeled and the results of time history response analysis were compared.
As described above, the input ground motion was five waves of El Centro NS, Taft EW, Notification Kobe NS, Notification Random, and Nankai Trough ground motion (OS1) (see FIG. 20 (f)).

  Here, the restoring force of a conventional seismic isolation structure is a bilinear type restoring force characteristic that uses a laminated rubber with lead plugs or a steel damper and a natural rubber laminated rubber, and the primary period is at 200% of the seismic isolation layer strain. It was set to 5 seconds. The restoring force of the conventional multi-layer seismic isolation structure and the seismic isolation structure of the present invention was set to be only natural rubber-based laminated rubber, and the primary period was set to about 7.5 seconds in the actual eigenvalue analysis.

Furthermore, the stiffness of the base isolation layer was determined so that γ was 2.0.
In addition, as a structural damping, 2% damping is given to each layer excluding the seismic isolation layer in proportion to rigidity. In addition, the conventional primary seismic isolation structure has a first-order damping constant including hysteresis damping obtained by equivalent linearization. In the conventional multi-layer seismic isolation structure, the damping coefficient of the seismic isolation layer is given in proportion to the rigidity so that the first-order damping constant is about 12% so that it becomes about 12%. On the other hand, in the seismic isolation structure of the present invention, the damping of the seismic isolation layer is given so that the sum of the damping coefficients to be applied is equal to the multi-layer seismic isolation after satisfying the applicable range. In all cases, the viscous damping was a bilinear type with a relief speed of 0.32 m / s, and the damping coefficient after relief was 0.0678 times the relief coefficient.

  Table 4 shows the analysis period and the natural period and attenuation constant obtained by the complex eigenvalue analysis.

  Moreover, in order to confirm the application range about the system of this invention, the design parameter (micro | micron | mu) and (alpha), (beta), and (gamma) about the item (Table 5) concentrated on 2 mass point system are shown in FIG. γ is 1.75, which satisfies 1.0 <γ <4.0.

  FIG. 23 to FIG. 26 show the results of comparing the response acceleration, interlayer deformation angle, and seismic isolation layer deformation of the conventional seismic isolation structure, the conventional multi-layer seismic isolation structure, and the seismic isolation structure of the present invention. .

  In any case, the seismic isolation structure of the present invention greatly reduces the response to the conventional seismic isolation, and the trend is almost the same as the result of analysis using a two-mass system. Furthermore, the deformation of the base isolation layer can be greatly reduced while the response acceleration is similar to that of the conventional multi-layer base isolation structure. Therefore, the superiority of the seismic isolation structure of the present invention has been demonstrated, and it has been demonstrated that each design parameter set in the applicable range can be applied to a multi-mass system.

  From the above results, in the seismic isolation structure A of the present embodiment, the following effects can be obtained by designing within the application range of each item (attenuation amount and rigidity ratio) shown in the present embodiment. It becomes possible.

An acceleration reduction effect surpassing general seismic isolation can be realized, and the response acceleration is 100 cm / s ² or less over the entire layer with respect to the earthquake motion currently used in the design. Thereby, there is an advantage that the elevator does not stop even in the event of a large earthquake.

  More specifically, the response acceleration can be halved with respect to normal seismic isolation by ultra-long period by multi-layer seismic isolation. In addition, the top acceleration (whipping response) can be reduced by increasing the rigidity of the upper frame with a rigid core. Response acceleration just below the middle seismic isolation layer, which increases the response acceleration in the conventional simple multi-layer seismic isolation structure, due to the coupling control with the core part 1 and the ideal stiffness ratio of each seismic isolation layer 3 and 4 Can also be suppressed. Furthermore, it is possible to suppress an increase in response acceleration due to overdamping of the higher order by the ideal damping distribution.

  Moreover, the effect of reducing the displacement of the seismic isolation layer surpassing that of general seismic isolation can be realized, and the deformation can be suppressed to about 70% of the ground motion used in the current design.

  That is, the damper under the core absorbs the earthquake energy of the higher floors, and the displacement of the entire building can be reduced efficiently. Moreover, since the deformation of the base isolation layer is dispersed by the multi-layer base isolation, the maximum response displacement of the base isolation layer can be reduced compared to the conventional base isolation. Furthermore, the seismic isolation layer displacement can be suppressed, and the seismic margin can be improved.

  As mentioned above, although 3rd Embodiment of the seismic isolation structure which concerns on this invention was described, this invention is not limited to said 3rd Embodiment, The meaning is included including 1st, 2nd embodiment. Changes can be made as appropriate without departing from the scope.

1 Core part 2 Main building part 3 Base seismic isolation layer 4 Middle seismic isolation layer 5 Damping device A Seismic isolation structure B Seismic isolation structure

Claims (6)

While having a core part and a building main part adjacent to the core part,
A multi-layer seismic isolation structure comprising a base seismic isolation layer provided at least in the lower part of the building main part of the core part and the building main part, and an intermediate base isolation layer provided in an intermediate part of the building main part, And the said base part and the said building main part are provided with the connection damping structure formed by connecting with a damping device, The seismic isolation structure characterized by the above-mentioned. In the seismic isolation structure according to claim 1,
The core part above the intermediate seismic isolation layer and the building main part are integrally formed,
The seismic isolation structure, wherein the core part below the intermediate seismic isolation layer and the main building part are connected by the damping device, and the lower part of the core part is a basic seismic isolation layer. In the seismic isolation structure according to claim 1,
The core part and the building main part below the intermediate seismic isolation layer are integrally formed,
The seismic isolation structure, wherein the core portion above the intermediate seismic isolation layer and the main building portion are connected by the vibration control device. In the seismic isolation structure according to claim 1,
The core part and the building main part are erected independently,
The seismic isolation structure, wherein the core portion above the intermediate seismic isolation layer and the main building portion are connected by the vibration control device. While having a core part and a building main part adjacent to the core part,
A multi-layer seismic isolation structure comprising a base seismic isolation layer provided at least in the lower part of the building main part of the core part and the main part of the building, and an intermediate base isolation layer provided in an intermediate part of the main part of the building. Prepared,
The core part above the intermediate seismic isolation layer and the building main part are integrally formed,
And the seismic isolation structure characterized by providing a seismic control apparatus in the said middle seismic isolation layer. In the seismic isolation structure according to any one of claims 1 to 5,
Specifications of seismic isolation layer stiffness k and damping c installed in the intermediate isolation layer and the basic isolation layer are set so as to satisfy the following formulas (1) to (4): Seismic structure.

Here, the mass above the upper structure than M _A is an intermediate isolation layer, the mass of M _B lower structure, k _1, k ₂ is exemption of each basic isolation layer and the intermediate layer base isolation layer Shinso stiffness, k ₃ is the base isolation layer rigid under the core _wall, c 1, c ₃ is attenuated to be installed in a basic seismic isolation layer and the core lower support portions respectively, c ₂ is not only the intermediate layer base isolation layer In addition, the eigenvector {r ₁ , r ₂ } is a characteristic vector of the mass points of the upper structure and the lower structure that are normalized with the maximum value being 1, including the damping of the joint control that connects the core wall and the lower structure.

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