JP7617763B2 - Building with low stiffness floor - Google Patents

Description

This disclosure relates to a building that includes a low-rigidity layer equipped with a vibration control device so that it has the same function as a seismic isolation layer.

Seismic isolation buildings, which have a seismic isolation layer equipped with a seismic isolation device such as laminated rubber bearings between the lower structure such as the foundation and the upper structure, have become widespread, reducing the response acceleration and inter-story displacement of the upper structure compared to earthquake-resistant buildings (for example, Patent Document 1). Non-Patent Document 1 speculates that in pilotis-style buildings, by using circular hoops in the pilotis columns made of reinforced concrete to increase the deformation capacity, the columns function as seismic isolation devices.

JP 2018-096501 A

"Concrete Engineering Vol. 58, No. 5", Japan Concrete Institute, May 2020, pp. 346-352

In seismic isolation layers that use conventional seismic isolation devices such as laminated rubber bearings, the laminated rubber bearings themselves are expensive, many seismic isolation devices are required to be installed under almost all columns of the superstructure, and footings and foundation beams are required above and below the seismic isolation devices, making the cost of constructing the seismic isolation layer high. Furthermore, in the invention described in Non-Patent Document 1, there was a need to develop a means to ensure the deformation capacity of larger columns and prevent excessive deformation.

In light of these problems, the present invention aims to provide a building that has the same functions as a seismically isolated building and can be constructed relatively inexpensively.

A building (1) according to an embodiment of the present invention is characterized by comprising a lower structure (2) including a lower beam (6) at the upper end, a plurality of upper columns (7), and an upper structure (3) including an upper beam (8) at the lower end and joined to the upper columns (7), a low-rigidity layer (4) arranged between the lower structure (2) and the upper structure (3), the low-rigidity layer (4) including low-rigidity columns (10, 61) having a lower bending rigidity than the upper columns (7) and joined to the lower beams (6) and the upper beams (8) to form a rigid frame structure (12) together with the lower beams (6) and the upper beams (8), and a vibration control device (5, 31, 41, 51) attached to the rigid frame structure (12) and configured to suppress displacement of the upper beams (8) relative to the lower beams (6) in the rigid frame structure (12) during an earthquake.

With this configuration, the low bending rigidity of the low-rigidity columns causes the rigid frame structure to deform significantly during an earthquake, but the vibration control device prevents excessive deformation of the rigid frame structure, allowing the low-rigidity layer to function in the same way as a seismic isolation layer. In addition, the building can be constructed relatively inexpensively because it does not use seismic isolation devices such as laminated rubber, which are relatively expensive.

In one embodiment of the present invention, in the above configuration, the low-rigidity columns (6, 61) include a first low-rigidity column (10a, 61a) joined to one of the lower beam (6) and the upper beam (8) to form a first joint corner (21), and a second low-rigidity column (10b, 61b) joined to the one of the upper beam (6) and the lower beam (8) to form a second joint corner (23), and the vibration control device (5, 31, 41, 51) includes a seesaw member (20, 32, 42) attached to the other of the lower beam (6) and the upper beam (8) via a pin joint (19) so as to be rotatable around an axial direction perpendicular to the structural plane including the rigid frame structure (12), and a vibration control device (5, 31, 41, 51) having one end that is rotatable around the axial direction perpendicular to the structural plane including the rigid frame structure (12). The system is characterized in that it includes a first tie rod (22) that is joined to the seesaw member (20, 32, 42) rotatably around the axis and the other end of which is joined to the first joint corner (21) rotatably around the axis, a second tie rod (24, 52) that is joined to the seesaw member (20, 32, 42) rotatably around the axis and the other end of which is joined to the second joint corner (23) rotatably around the axis, and a damper (25) attached to the seesaw member (20, 32, 42) and the other of the lower beam (6) and the upper beam (8) to suppress the rotation of the seesaw member (20, 32, 42) around the axis.

With this configuration, the vibration control device can be manufactured at a relatively low cost, and since it is only necessary to install one per structural surface, construction costs can be reduced.

One embodiment of the present invention is characterized in that in a direct-above configuration, the vibration control device (5, 31, 41, 51) is arranged on the exterior surface of the building (1).

This configuration allows for effective use of the interior of the low-rigidity layer.

One embodiment of the present invention is characterized in that in the second or third configuration, the lower structure (2) is a foundation structure, the other of the lower beam (6) and the upper beam (8) is the lower beam (6), and the lower beam (6) is a foundation beam.

The member to which the seesaw member of the vibration control device is attached via the pin joint receives a large force from the seesaw member and the damper, but with this configuration, the seesaw member is attached to the foundation beam, which is already strong, so there is no need to reinforce the lower beam to attach the seesaw member.

In one embodiment of the present invention, in any of the above configurations, the low-rigidity columns (10, 61) are made of unbonded prestressed concrete.

This configuration reduces the bending stiffness of the low stiffness columns, significantly increasing the undamaged vibration region where the rigid frame structure elastically vibrates.

One embodiment of the present invention is characterized in that in the direct-above configuration, the lower ends of the low-rigidity columns (61) that join to the lower beam have a narrower cross section than the portion directly above them and/or contain fewer main reinforcements (13) than the portion directly above them.

This configuration allows the bending stiffness of the low stiffness columns to be further reduced.

In one embodiment of the present invention, in the fifth or sixth configuration, the low-rigidity columns (10, 61) include a steel or fiber-reinforced plastic restraining member (18) that contacts the outer surface of the concrete portion (15) over the entire circumference, and/or includes steel or resin fibers within the concrete portion.

With this configuration, the restraining member or fiber provides a confining effect, preventing the concrete portion from collapsing.

An embodiment of the present invention is characterized in that in any of the above configurations except for the configuration in which the low-rigidity columns are made of unbonded prestressed concrete, the upper columns (7) are made of steel, and the low-rigidity columns (10) are made of steel with a smaller cross section than the upper columns (7).

This configuration allows the construction of low-rigidity columns with lower bending rigidity than the upper columns in steel-framed buildings.

In one embodiment of the present invention, in any of the above configurations, the low-rigidity columns (10, 61) are characterized in that they have a height of one or more stories in the upper structure.

With this configuration, the low-rigidity columns are longer, which lengthens the vibration period of the low-rigidity layer and allows for effective use of the interior of the low-rigidity layer.

The present invention makes it possible to provide a building with a low-rigidity layer that has the same function as a seismic isolation layer, can be constructed relatively inexpensively, and has sufficient deformation capacity.

FIG. 1 is a front view of a building according to an embodiment; FIG. 1 is a front view showing a modified example of a building according to an embodiment; FIG. 1 is a cross-sectional view showing a low-rigidity column of a building according to an embodiment. FIG. 1 is a front view showing a first modified example of a vibration damping device according to an embodiment; FIG. 11 is a front view showing a second modified example of the vibration damping device according to the embodiment; FIG. 13 is a front view showing a third modified example of the vibration damping device according to the embodiment; FIG. 1 is a front view showing a modified example of a low-rigidity column according to an embodiment of the present invention;

Below, a building 1 according to an embodiment of the present invention will be described with reference to the drawings. As shown in FIG. 1, the building 1 comprises a lower structure 2, an upper structure 3, a low-rigidity layer 4 disposed between the lower structure 2 and the upper structure 3, and a vibration control device 5 disposed within the low-rigidity layer 4. In the example shown in FIG. 1, the low-rigidity layer 4 is provided in the aboveground portion, but as shown in FIG. 2, the low-rigidity layer 4 may also be provided in the underground portion.

As shown in Figures 1 and 2, the lower structure 2 is a foundation structure built on the ground, and a lower beam 6, which is a foundation beam, is provided at the upper end of the lower structure. The lower structure 2 may include the lower floor portion of the building 1 in addition to the foundation structure, in which case the beam provided at the upper end of the lower floor portion becomes the lower beam 6.

The upper structure 3 includes a plurality of upper columns 7, an upper beam 8 provided at the lower end of the upper structure 3 and joined to the plurality of upper columns 7, and a plurality of upper beams 9 provided above the upper beam 8 and joined to the plurality of upper columns 7.

The low-rigidity layer 4 is joined at its lower end to the lower beam 6 and at its upper end to the upper beam 8, and includes a plurality of low-rigidity columns 10 having a lower bending rigidity than the plurality of upper columns 7, and an inner-story beam 11 joined to the middle of the plurality of low-rigidity columns 10. The lower beam 6, the upper beam 8, and the low-rigidity columns 10 form a rigid frame structure 12. The plurality of low-rigidity columns 10 include a first low-rigidity column 10a arranged at one end in the lateral direction on one exterior surface of the building 1, a second low-rigidity column 10b arranged at the other end, and a third low-rigidity column 10c arranged between the first low-rigidity column 10a and the second low-rigidity column 10b. The plurality of low-rigidity columns 10 are preferably arranged on an extension line of the plurality of upper columns 7. The illustrated low-rigidity layer 4 has a two-story structure, but the low-rigidity layer 4 may be a one-story structure without an inner-story beam 11, or a three-story structure with a plurality of inner-story beams 11 at different positions in the vertical direction.

The column-beam structure of the building 1 is made of reinforced concrete. The column-beam structure of the building 1 may be constructed using precast concrete members, cast-in-place concrete, or a combination of both. When using precast concrete members, large precast concrete members may be used to reduce the labor required for construction and improve productivity, or divided precast concrete members may be used to reduce weight and enable lifting with a relatively small crane. The low-rigidity columns 10 are made of unbonded prestressed concrete to have a lower bending rigidity than the upper columns 7, and are preferably thinner than the upper columns 7.

As shown in FIG. 3, each low-rigidity column 10 includes a plurality of main reinforcements 13 extending in the vertical direction, a plurality of tie bars 14 extending in the horizontal direction so as to surround the plurality of main reinforcements 13, a concrete portion 15 in which the main reinforcements 13 and tie bars 14 are embedded, and a tension member 16 that is not attached to the concrete portion 15. It is preferable to use a PC steel rod as the tension member 16, but PC steel wire, PC steel strand, etc. may also be used. The tension member 16 is inserted into a hole 17 extending in the vertical direction in the concrete portion 15, and is fixed to both the upper and lower ends of the low-rigidity column 10 while a tensile force is applied thereto, thereby applying prestress to the low-rigidity column 10.

Each of the low-rigidity columns 10 preferably further includes a restraining member 18, such as a steel sheet or steel pipe, or a sheet made of fiber-reinforced plastic such as carbon fiber or aramid fiber, that abuts the outer surface of the concrete portion 15 over the entire circumference. Although a large compressive force is applied to the concrete portion 15 of the low-rigidity column 10, the restraining member 18 provides a confining effect, preventing the concrete portion 15 from collapsing. Instead of or in addition to the restraining member 18, the concrete portion 15 may include steel fibers or resin fibers to provide a confining effect.

The column-beam structure of the building 1 may be made of steel instead of reinforced concrete. In this case, the low-rigidity columns 10 have a smaller cross section than the upper columns 7, and therefore have a lower bending rigidity than the upper columns 7.

Hereinafter, the direction perpendicular to the structural plane including the rigid frame structure 12 having the first and second low-rigidity columns 10a, 10b (the direction perpendicular to the plane of the paper in Figures 1 and 2) will be referred to as the "axial direction." As shown in Figures 1 and 2, the vibration control device 5 is a device equipped with a so-called oscillating vibration control mechanism, and includes a seesaw member 20 attached to the lower beam 6 via a pin joint 19 so as to be rotatable around the axial direction, a first tie rod 22 having one end joined to the seesaw member 20 so as to be rotatable around the axial direction and the other end joined to a first joint corner 21 formed by the upper end of the first low-rigidity column 10a and one end of the upper beam 8 so as to be rotatable around the axial direction, a second tie rod 24 having one end joined to the seesaw member 20 so as to be rotatable around the axial direction and the other end joined to a second joint corner 23 formed by the upper end of the second low-rigidity column 10b and the other end of the upper beam 8 so as to be rotatable around the axial direction, and a pair of dampers 25 attached to the seesaw member 20 and the lower beam 6 to suppress rotation of the seesaw member 20 around the axial direction. The first and second tie rods 22, 24 cross each other above the pin joint 19, and their lower ends are joined to both ends of the seesaw member 20. The crossing position of the first and second tie rods 22, 24 is located on the lower beam 6 side rather than the center between the lower beam 6 and the upper beam 8. The first and second tie rods 22, 24 are joined to the first and second joint corners 21, 23 via gusset plates 26 (see FIG. 4).

The pin joint 19 is fixed to the lower beam 6 and supports the seesaw member 20 so that it can rotate about the axial direction. The pin joint 19 may be formed, for example, by a clevis.

The seesaw member 20 includes a long member that extends approximately parallel to the extension direction of the lower beam 6 during non-earthquakes, and steel materials such as structural steel can be used as the long member.

The first and second tie rods 22, 24 include steel rods with both ends formed into a fork shape so that they can be pin-joined to other members. Instead of being composed of a single steel rod, the first and second tie rods 22, 24 may each include two steel rods with their distal ends formed into a fork shape and a turnbuckle 27 (see FIG. 4) that connects the ends of the two steel rods that are close to each other. It is preferable that the lengths of the first and second tie rods 22, 24 are approximately equal to each other, and that the angles of the first and second tie rods 22, 24 with respect to the upper beam 8 are approximately equal to each other. It is preferable to introduce a tensile force to both the first and second tie rods 22, 24 in advance so that a tensile force is applied to both the first and second tie rods 22, 24 during a non-earthquake.

The pair of dampers 25 are arranged to sandwich the pin joint 19, and are fixed at their lower ends to the lower beam 6 and at their upper ends near both ends of the seesaw member 20 in the extension direction. The dampers 25 are vibration dampers, and are, for example, hysteretic dampers such as steel dampers, oil dampers, or viscoelastic dampers. The pair of dampers 25 may be the same or different. The pair of dampers 25 apply damping forces in the vertical direction to both ends of the seesaw member 20.

The vibration control device 5 acts to suppress deformation of the rigid frame structure 12 during an earthquake. The following description focuses on the rectangular rigid frame structure 12 composed of the lower beam 6, upper beam 8, and first and second low-rigidity columns 10a, 10b.

During an earthquake, when the upper beam 8 receives a seismic force (inertia force) toward the right in FIG. 1 relative to the lower beam 6, the upper beam 8 moves while remaining parallel to the lower beam 6 so that the multiple low-rigidity columns 10 tilt and/or curve to the right, and the rectangular rigid frame structure 12 is deformed. In the deformed rigid frame structure 12, the diagonal line connecting the upper right corner and the lower left corner becomes longer and the diagonal line connecting the upper left corner and the lower right corner becomes shorter compared to before the deformation. Since the diagonal line connecting the upper right corner and the lower left corner of the rigid frame structure 12 becomes longer, a tensile force is generated in the second tie rod 24, and this tensile force acts on the rigid frame structure 12 in a direction that resists the seismic force. In addition, the tensile force generated in the second tie rod 24 rotates the seesaw member 20 clockwise around the axis. This rotation widens the distance between the parts where both ends of the first tie rod 22 are joined, i.e., the distance between the first joint corner 21 and one end of the seesaw member 20 (the right end in FIG. 1). The increase in the distance between the first joint corner 21 and the right end of the seesaw member 20 due to this rotation is roughly equal to the decrease in length in the direction compressing the first tie rod 22 due to the shortening of the diagonal line connecting the upper left corner and the lower right corner of the rigid frame structure 12, so the length of the first tie rod 22 remains roughly the same as in the absence of an earthquake, and the application of compressive force to the first tie rod 22 is suppressed.

Next, when the direction of the earthquake vibration changes and the upper beam 8 is subjected to a seismic force toward the left in FIG. 1 relative to the lower beam 6, a tensile force is generated in the first tie rod 22 by the damping force from the damper 25 while the low-rigidity column 10 returns from its rightward inclined and/or curved state to a vertical state, and this tensile force acts on the rigid frame structure 12 in a direction that resists the seismic force.

When the low-rigidity column 10 is tilted and/or curved to the left, the diagonal line connecting the upper left corner and the lower right corner of the deformed rigid frame structure 12 becomes longer and the diagonal line connecting the upper right corner and the lower left corner becomes shorter compared to before the deformation. Since the diagonal line connecting the upper left corner and the lower right corner of the rigid frame structure 12 becomes longer, a tensile force is generated in the first tie rod 22, and this tensile force acts on the rigid frame structure 12 in a direction that resists the earthquake force. In addition, the tensile force generated in the first tie rod 22 rotates the seesaw member 20 counterclockwise around the axis. This rotation widens the distance between the part where both ends of the second tie rod 24 are joined, i.e., between the second joint corner 23 and the other end of the seesaw member 20 (the left end in FIG. 1). The increase in the distance between the second joint corner 23 and the left end of the seesaw member 20 due to this rotation is roughly equal to the decrease in length in the direction compressing the second tie rod 24 due to the shortening of the diagonal line connecting the upper right corner and the lower left corner of the rigid frame structure 12, so the length of the second tie rod 24 remains roughly the same as in the absence of an earthquake, and the application of compressive force to the second tie rod 24 is suppressed.

Next, when the direction of the earthquake vibration changes and the upper beam 8 is subjected to a seismic force toward the right in FIG. 1 relative to the lower beam 6, a tensile force is generated in the second tie rod 24 by the damping force from the damper 25 while the low-rigidity column 10 returns from its leftward inclined and/or curved state to a vertical state, and this tensile force acts on the rigid frame structure 12 in a direction that resists the seismic force.

The vibration control device 5 repeats the above-mentioned movements during an earthquake to prevent excessive deformation of the rigid frame structure 12.

Because the low-stiffness columns 10 are made of unbonded prestressed concrete, the occurrence of strain in the tendons 16 made of PC steel bars that resist bending moments is suppressed, and the bending stiffness of the low-stiffness columns 10 is reduced. Because the low-stiffness columns 10 have lower bending stiffness than the upper columns 7, the elastically vibrating undamaged vibration region of the rigid frame structure 12 becomes significantly larger, and the low-stiffness layer 4 performs the same function as a seismic isolation layer. In addition, by attaching the vibration control devices 5 to the rigid frame structure 12, excessive deformation of the rigid frame structure 12 can be prevented.

In the low-rigidity column 10, a confining effect is obtained by the restraining member 18 and/or the fibers contained in the concrete portion 15, preventing the concrete portion 15 from collapsing.

The vibration control device 5 can be manufactured at a relatively low cost, and since it is sufficient to install one per structural surface, the construction cost is lower than that of seismic isolation layers that use laminated rubber bearings, etc., which have a high unit price, require a large number of units, and require the construction of foundations for installation. In addition, the low-rigidity layer 4 can be made almost maintenance-free.

By placing the vibration control device 5 on the exterior surface, the inside of the low-rigidity layer 4 can be effectively utilized. For example, the low-rigidity layer 4 can be used as a parking lot, a facility machine room, or a water supply facility. In addition, by having the low-rigidity column 10 have a height of one or more stories in the upper structure 3, the inside of the low-rigidity layer 4 can also be effectively utilized.

The vibration control device 5 includes a seesaw member 20 and first and second tie rods 22, 24 joined to the seesaw member 20, and concentrates the displacement of each layer spanned by the first and second tie rods 22, 24 to one location. The seesaw member 20 switches horizontal displacement to vertical displacement and reduces the effect of the compression side of the first and second tie rods 22, 24. In other words, the vibration control device 5 concentrates the deformation of the low-rigidity layer 4, which functions as a seismic isolation layer, to one location through the action of the seesaw member 20, without considering the prevention of buckling of the first and second tie rods 22, 24. The vibration control device 5 also absorbs the vibration energy of an earthquake using the dampers 25.

By considering the weight of the low-rigidity layer 4 and the length of the low-rigidity column 10, the entire building 1 can be made to have a long period, and the building 1 has a vibration reduction effect equivalent to that of a seismic isolation construction method, despite being a vibration control construction method.

The lower beam 6 is subjected to a large force from the vibration control device 5, so it needs to have a corresponding strength. The foundation beams of foundation structures are large due to the need for underground pits, etc. By using such a strong foundation beam as the lower beam 6, it is possible to suppress increases in construction costs. In addition, the lower beam 6, which is a foundation beam, appropriately transmits the concentrated reaction force from the vibration control device 5 to the ground or pile body (not shown).

Figures 4 to 6 show first to third modified examples of the vibration damping device 5 in the above embodiment. The vibration damping devices 31, 41 according to the first and second modified examples shown in Figures 4 and 5 differ from the above embodiment in the shape of the seesaw members 32, 42. The vibration damping device 51 according to the third modified example shown in Figure 6 differs from the above embodiment in that the second tie rod 52 includes a cross turnbuckle 53. In the explanation, configurations that are common or similar to those in the above embodiment are given the same reference numerals and explanations are omitted.

The seesaw member 32 of the vibration control device 31 shown in FIG. 4 is composed of a triangular frame material in which three long members are rigidly connected at their ends, and the surface defined by the triangular frame is parallel to the structural surface of the rigid frame structure 12 (see FIG. 1) including the first and second low-rigidity columns 10a, 10b. Steel materials such as shaped steel may be used as the long members. The seesaw member 32 can be considered as a rigid body against earthquake forces acting in the left-right and up-down directions of the structural surface on which it is installed, and may be composed of other shapes and/or other materials as long as it has a left-right length and a up-down length, for example, it may be formed of a triangular steel panel material when viewed from the front. The triangular seesaw member 32 is preferably an isosceles triangle, with the base arranged horizontally and a pair of equal sides arranged so that they approach each other upward from both ends of the base.

The lower ends of the first and second tie rods 22, 24 are joined to the triangular seesaw member 32 near the apex of the upper part of the triangular seesaw member 32 so as to be rotatable around the axis. This joint point is preferably aligned with the pin joint 19 in the vertical direction, and its vertical position is closer to the lower beam 6 than the center between the lower beam 6 and the upper beam 8 (see Figure 1), and is above the rotation axis of the pin joint 19. During non-earthquakes, the first and second tie rods 22, 24 are preferably positioned on the extensions of the members that make up the sides extending from the apex of the upper part of the triangular seesaw member 32.

Even with this configuration, the vibration damping device 31 has the same effect as the vibration damping device 5 of the above embodiment.

The seesaw member 42 of the vibration damping device 41 shown in FIG. 5 has an inverted Y shape when viewed from a direction perpendicular to the structural surface on which the vibration damping device 41 is installed, and is formed by rigidly joining one end of three long steel members such as structural steel members together by welding or fastening with fasteners (not shown).

The rotation axis of the pin joint 19 is located above the joint between the seesaw member 42 and the damper 25.

The seesaw member 42 may have a shape other than an inverted Y-shape, so long as it can be regarded as a rigid body against earthquake forces acting in the left-right and up-down directions on the structural surface on which the vibration control device 41 is installed, has a left-right length and a up-down length, and is a shape that allows the rotation axis of the pin joint 19 to be positioned above the connection between the seesaw member 42 and the damper 25. For example, the seesaw member 42 may have a shape that is modified such that the center of the lower side is concave upward compared to the shape of the seesaw member 32 of the first modified example (see FIG. 4).

By positioning the rotation axis of the pin joint 19 above the connection between the seesaw member 42 and the damper 25, the distance between the rotation axis of the pin joint 19 and the joints of the first and second tie rods 22, 24 to the seesaw member 42 is shortened. If the displacement of this joint during an earthquake is the same, the shorter the distance between the two, the larger the rotation angle of the seesaw member 42. Therefore, the displacement of the damper 25 can be amplified more than in the first embodiment without increasing the length of the seesaw member 42 in the left-right direction. This improves the energy absorption efficiency of the vibration control device 41.

The inverted Y-shaped seesaw member 42 has an inwardly concave inverted Y shape compared to the triangular seesaw member 32 of the first modified example, so the space in the left and right concave portions can be effectively utilized. For example, this space can be used as installation space for a jack or the like for introducing a tensile force to the first and second tie rods 22, 24.

As shown in FIG. 6, in the vibration damping device 51 according to the third modified example, the second tie rod 52 includes a cross turnbuckle 53. The cross turnbuckle 53 has a through hole 54 through which the first tie rod 22 is inserted. By inserting the first tie rod 22 into the through hole 54, the first and second tie rods 22, 52 can be arranged on approximately the same plane.

Figure 7 shows a low-rigidity column 61 according to a modified example. As in the above embodiment, the low-rigidity column 61 includes a first low-rigidity column 61a arranged at one end, a second low-rigidity column 61b arranged at the other end, and a third low-rigidity column 61c arranged between the first low-rigidity column 61a and the second low-rigidity column 61b on the exterior surface. In addition to being made of unbonded prestressed concrete, the low-rigidity column 61 has a narrower cross section at its lower end, which is joined to the lower beam 6, than the portion directly above it, and/or includes fewer main reinforcements 13 than the portion directly above it. For this reason, the low-rigidity column 61 is more likely to swing around the base of the column, further reducing its bending rigidity.

Although the description of the specific embodiment is finished above, the present invention is not limited to the above embodiment and can be widely modified. The vibration control device may be arranged upside down. That is, a seesaw member may be attached to the upper beam via a pin joint, the upper ends of the first and second tie rods may be joined to the seesaw member, and the lower ends may be joined to the joint corners between the first and second low-rigidity columns and the lower beam. The vibration control device may be installed on the interior structural surface instead of the exterior structural surface, and the first and second low-rigidity columns may be low-rigidity columns arranged in the middle of the structural surface instead of at the left and right ends. As the vibration control device, a known vibration control device other than a device having a rocking vibration control mechanism, such as a hysteretic rigidity damper, a viscous damper, or a brace-type oil damper, may be used.

Reference Signs List 1: Building 2: Lower structure 3: Upper structure 4: Low rigidity layer 5, 31, 41, 51: Vibration damping device 6: Lower beam 7: Upper column 8: Upper beam 10, 61: Low rigidity column 10a, 61a: First low rigidity column 10b, 61b: Second low rigidity column 12: Rigid frame structure 13: Main reinforcement 15: Concrete portion 16: Tendon 18: Restraint member 19: Pin joint 20, 32, 42: Seesaw member 21: First joint corner 22: First tie rod 23: Second joint corner 24, 52: Second tie rod 25: Damper

Claims (9)

A lower structure including a lower beam provided at an upper end;
An upper structure including a plurality of upper columns and an upper beam provided at a lower end and joined to the upper columns;
a low-rigidity layer disposed between the lower structure and the upper structure, the low-rigidity layer having a bending rigidity lower than that of the upper column and including a low-rigidity column joined to the lower beam and the upper beam to form a rigid frame structure together with the lower beam and the upper beam;
a vibration control device attached to the rigid frame structure and configured to suppress displacement of the upper beam relative to the lower beam in the rigid frame structure during an earthquake;
Equipped with
The plurality of low-rigidity columns include a first low-rigidity column joined to one of the lower beam and the upper beam to form a first joint corner, and a second low-rigidity column joined to the one of the upper beam and the lower beam to form a second joint corner,
The vibration damping device is
a seesaw member attached to the other of the lower beam and the upper beam via a pin joint so as to be rotatable about an axis perpendicular to a structural face including the rigid frame structure;
a first tie rod having one end joined to the seesaw member so as to be rotatable about the axial direction and having the other end joined to the first joint corner portion so as to be rotatable about the axial direction;
a second tie rod having one end joined to the seesaw member so as to be rotatable about the axial direction and having the other end joined to the second joint corner portion so as to be rotatable about the axial direction;
a damper attached to the seesaw member and the other of the lower beam and the upper beam to suppress rotation of the seesaw member about the axial direction;
A building comprising : The building according to claim 1 , wherein the vibration control device is disposed on an exterior surface of the building. The lower structure is a foundation structure,
the other of the lower beam and the upper beam is the lower beam,
The building according to claim 1 or 2 , characterized in that the lower beam is a foundation beam. The building according to any one of claims 1 to 3 , characterized in that the plurality of low-rigidity columns are made of unbonded prestressed concrete. The building described in claim 4, characterized in that the lower ends of the multiple low-rigidity columns that join to the lower beam have a narrower cross-section than the portion immediately above and/or contain fewer main reinforcement bars than the portion immediately above. The building described in claim 4 or 5, characterized in that the multiple low-rigidity columns include a restraining member made of steel or fiber-reinforced plastic that abuts the outer surface of the concrete portion around its entire circumference, and / or includes steel or resin fibers within the concrete portion. The upper columns are made of steel,
The building according to any one of claims 1 to 3 , characterized in that the low-rigidity columns are of steel frame construction having a smaller cross section than the upper columns. The building according to any one of claims 1 to 7 , characterized in that the plurality of low-rigidity columns have a height of one or more stories in the upper structure. A lower structure including a lower beam provided at an upper end;
An upper structure including a plurality of upper columns and an upper beam provided at a lower end and joined to the upper columns;
a low-rigidity layer disposed between the lower structure and the upper structure, the low-rigidity layer having a bending rigidity lower than that of the upper column and including a low-rigidity column joined to the lower beam and the upper beam to form a rigid frame structure together with the lower beam and the upper beam;
a vibration control device attached to the rigid frame structure and configured to suppress displacement of the upper beam relative to the lower beam in the rigid frame structure during an earthquake;
Equipped with
The low stiffness columns are made of unbonded prestressed concrete,
A building characterized in that the multiple low-rigidity columns include a restraining member made of steel or fiber-reinforced plastic that abuts the outer surface of the concrete portion around its entire circumference, and/or includes steel or resin fibers within the concrete portion.

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