JP7446945B2 - Friction damper mechanism - Google Patents

Description

The present invention relates to a friction damper mechanism.

Generally, a friction damper is a device that is installed between the layers of a vibration-isolating and damping structure to suppress inter-layer displacement during an earthquake (see Patent Document 1 below). In the case of a seismic isolation structure, the friction damper is installed in the seismic isolation layer, and in the case of a vibration damping structure, it is installed in the layer where the damping device is installed.

As shown in FIG. 19, the general principle of the friction damper is that a tightening force is applied to the inner cylinder 102 from the outer cylinder 101, and the history due to the relative displacement between the outer cylinder 101 and the inner cylinder 102 and the frictional force of the contact surface is applied. It absorbs earthquake energy by absorbing energy.

As shown in FIG. 20, the restoring force characteristic of the friction damper has a rectangular shape in which the frictional force is constant regardless of increases or decreases in the axial displacement of the damper.

JP2017-48581A

However, in conventional friction dampers, since the frictional force is constant, the damper will not be displaced unless the axial force applied to the damper due to an earthquake exceeds the frictional force. For this reason, if we increase the frictional force in response to large earthquakes, the axial force generated on the damper will not exceed the frictional force and no displacement will occur during small and medium-sized earthquakes, which occur more often, so there will be no hysteresis absorbed energy, and the function as a friction damper will no longer function. I can't accomplish it. On the other hand, if the frictional force is reduced so as to be effective against small and medium-sized earthquakes, there is a problem in that the hysteresis absorbed energy becomes small in the event of a large earthquake, resulting in a small response reduction effect.

Therefore, the present invention has been made in view of the above circumstances, and provides a friction damper mechanism that generates a small frictional force during a small to medium earthquake where the axial displacement of the damper is small, and generates a large frictional force during a large earthquake where the axial displacement of the damper is large. I will provide a.

In order to achieve the above object, the present invention employs the following means.
That is, the friction damper mechanism according to the present invention includes a first friction damper device and a second friction damper device that are arranged in parallel with each other between an upper structure and a lower structure, and the first friction The damper device includes a first upper connecting plate connected to the upper structure, and a damper device arranged coaxially and spaced apart from the first upper connecting plate in the axial direction, connected to the lower structure, and connected to the first upper connecting plate. a first lower connecting plate material formed so that the thickness in the vertical direction gradually increases as it approaches the connecting plate material; a first upper side plate material disposed above the first upper connecting plate material; a first lower plate disposed below the lower connecting plate; a first friction plate disposed between the first lower connecting plate and the first upper plate and the first lower plate; , maintaining the distance between the first upper plate and the first lower plate so that it does not become less than a predetermined dimension, and applying bearing pressure to the first lower connecting plate with the first upper plate and the first lower plate. and a first movement restraint part that restrains the movement of the first upper connecting plate, the first upper plate, and the first lower plate in the axial direction, and the second The friction damper device includes a second lower connecting plate connected to the lower structure, and a friction damper device arranged coaxially and spaced apart from the second lower connecting plate in the axial direction, connected to the upper structure, and connected to the second lower connecting plate. a second upper connecting plate material formed so that the thickness in the vertical direction gradually increases as the distance from the lower connecting plate material increases, a second upper side plate material disposed above the second upper connecting plate material, and the second upper connecting plate material; a second lower plate disposed below the lower connecting plate; a second friction plate disposed between the second upper connecting plate and the second upper plate and the second lower plate; A second upper connecting plate that applies bearing pressure to the second upper connecting plate by the second upper plate and the second lower plate while maintaining the distance between the second upper plate and the second lower plate so that it does not become less than a predetermined dimension. It is characterized by having two support pressure parts and a second movement restraint part that restrains the movement of the second lower connecting plate, the second upper plate, and the second lower plate in the axial direction.

In the friction damper mechanism configured in this way, when a tensile force acts on the first friction damper device, the friction force acting on the first upper friction plate material and the first lower friction plate material increases, and when a compressive force acts on the first friction damper device, the friction force acts on the first upper friction plate material and the first lower friction plate material. The friction force acting on the first upper friction plate material and the first lower friction plate material is almost eliminated. When a compressive force acts on the second friction damper device, the friction force acting on the second upper friction plate material and the second lower friction plate material increases, and when a tensile force acts on the second friction damper device, the second upper friction plate material and the second lower friction plate material increase. The frictional force acting on the surface almost disappears. Therefore, since the first friction damper device and the second friction damper device are arranged in parallel, the relationship between load and displacement is a superposition of both, and in the case of a small to medium earthquake where the axial displacement of the damper is small. A small frictional force is generated, and a large frictional force can be generated during a large earthquake when the damper's axial displacement is large.

Further, the friction damper mechanism according to the present invention is a friction damper mechanism installed between an upper structure and a lower structure, and includes a piston rod connected to one of the upper structure and the lower structure. , a housing section connected to the other of the upper structure and the lower structure; an upper member disposed inside the housing section; and an upper member disposed inside the housing section below the upper member. a lower member provided on the piston rod, interposed between the upper member and the lower member, and capable of sliding in one horizontal direction with respect to the upper member and the lower member. the slider, an upper biasing section that biases the upper member toward the slider, and a lower biasing section that biases the lower member toward the slider; The sliding surfaces of the slider and the upper member include a first upper inclined surface and a second upper inclined surface that are both along the horizontal direction and inclined in opposite directions with respect to the horizontal plane. The sliding surfaces of the slider and the lower member are both along the other horizontal direction and opposite to each other with respect to the horizontal plane. A first lower inclined surface and a second lower inclined surface which are inclined in the direction are arranged side by side in the other horizontal direction.

In the friction damper mechanism configured in this way, when a tensile force is applied during an earthquake, sliding occurs between the slider and the upper member on one of the first upper inclined surface and the second upper inclined surface. At the same time, sliding occurs between the slider and the lower member on one of the first lower inclined surface and the second lower inclined surface. When compressive force is applied during an earthquake, sliding occurs between the slider and the upper member on the other of the first upper inclined surface and the second upper inclined surface, and the slider and the lower member Sliding occurs between the first lower inclined surface and the second lower inclined surface. In both cases of tensile force and compressive force, as the amount of displacement increases, the frictional resistance force also increases, so small frictional force is generated during small to medium earthquakes where the damper's axial displacement is small, and during large earthquakes where the damper's axial displacement is large. Sometimes large frictional forces can be generated.

According to the friction damper mechanism according to the present invention, a small frictional force is generated during a small to medium earthquake where the axial displacement of the damper is small, and a large frictional force can be generated during a large earthquake where the axial displacement of the damper is large.

FIG. 1 is a schematic diagram showing a friction damper mechanism according to a first embodiment of the present invention. It is a figure which shows the 1st friction damper device of the friction damper mechanism based on 1st embodiment of this invention, (a) is the X1-X1 sectional view (vertical sectional view) of (b), and (b) is FIG. 3 is a plan view, (c) is a sectional view (vertical sectional view) taken along the line X2-X2 of (b), and (d) is a diagram showing the restoring force of the first friction damper device. It is a figure which shows the 2nd friction damper device of the friction damper mechanism based on 1st embodiment of this invention, (a) is the X3-X3 sectional view (vertical sectional view) of (b), and (b) is FIG. 4 is a plan view, (c) is a sectional view (vertical sectional view) taken along the line X4-X4 of (b), and (d) is a diagram showing the restoring force of the second friction damper device. It is a figure showing the history characteristic of the friction damper mechanism concerning a first embodiment of the present invention. FIG. 7 is a schematic diagram showing a friction damper mechanism according to a second embodiment of the present invention. FIG. 6 is a vertical sectional view of a friction damper mechanism according to a second embodiment of the present invention. FIG. 7 is a perspective view showing an upper member of a friction damper mechanism according to a second embodiment of the present invention. It is a perspective view showing a lower member and a slider of a friction damper mechanism according to a second embodiment of the present invention. It is an operation diagram of the friction damper mechanism concerning the second embodiment of the present invention, (a) shows the case where force acts in the direction where the piston rod pops out from the housing part, and (b) shows the case where the piston rod is pushed out from the housing part. This shows the case where a force acts in the direction of entering the inside of the FIG. 3 is a diagram showing an analysis model. It is a diagram showing seismic waves used in analysis. The restoring force of the damper is shown, and (a) is the present embodiment (displacement-dependent friction damper), and (b) is the conventional friction damper. The analysis results of seismic waves (L2 level of El Centro) are shown, (a) shows the relationship between the maximum response acceleration and _R50 , and (b) shows the relationship between the maximum response displacement and _R50 . The analysis results of seismic waves (L1 level of El Centro) are shown, (a) shows the relationship between the maximum response acceleration and _R50 , and (b) shows the relationship between the maximum response displacement and _R50 . The analysis results of seismic waves (Tuft's L2 level) are shown, in which (a) shows the relationship between the maximum response acceleration and _R50 , and (b) shows the relationship between the maximum response displacement and _R50 . The analysis results of seismic waves (Tuft's L1 level) are shown, with (a) showing the relationship between the maximum response acceleration and _R50 , and (b) showing the relationship between the maximum response displacement and _R50 . The analysis results of seismic waves (L2 level of Hachinohe) are shown, (a) shows the relationship between the maximum response acceleration and _R50 , and (b) shows the relationship between the maximum response displacement and _R50 . The analysis results of seismic waves (L1 level of Hachinohe) are shown, (a) shows the relationship between the maximum response acceleration and _R50 , and (b) shows the relationship between the maximum response displacement and _R50 . FIG. 2 is a diagram showing the principle of a conventional friction damper structure. FIG. 3 is a diagram showing the restoring force of a conventional friction damper.

(First embodiment)
A friction damper mechanism according to an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic diagram showing a friction damper mechanism according to a first embodiment of the present invention.
As shown in FIG. 1, a friction damper mechanism 100 according to the present embodiment is installed between a seismic isolation upper structure (upper structure) A1 and a seismic isolation lower structure (lower structure) A2.

An upper fixing portion A11 is provided at the lower part of the seismic isolation upper structure A1. Lower fixing parts A21 and A22 are provided at the upper part of the seismic isolation lower structure A2. The lower fixing part A21 and the lower fixing part A22 are spaced apart from each other in the horizontal direction. The upper fixing part A11 is arranged between the lower fixing part A21 and the lower fixing part A22.

The friction damper mechanism 100 includes a first friction damper device 1 and a second friction damper device 2. The first friction damper device 1 is arranged between the upper fixing part A11 and the lower fixing part A21. The second friction damper device 2 is arranged between the upper fixing part A11 and the lower fixing part A22. The first friction damper device 1 and the second friction damper device 2 are arranged on a straight line and are arranged in parallel between the seismic isolation upper structure A1 and the seismic isolation lower structure A2.

The first friction damper device 1, the second friction damper device 2, the upper fixing part A11, the lower fixing part A21, and the lower fixing part A22 are arranged coaxially on the axis O1.

Here, in the axis O1 direction (axial direction), the lower fixing part A21 side is defined as the +O1 side, and the lower fixing part A22 side is defined as the -O1 side.

FIG. 2 is a diagram showing the first friction damper device 1, in which (a) is a sectional view (vertical sectional view) taken along the line X1-X1 of (b), (b) is a plan view, and (c) is a sectional view (vertical sectional view) taken along the line X2-X2 of (b), and (d) is a diagram showing the restoring force of the first friction damper device 1.
As shown in FIG. 2, the first friction damper device 1 includes a first upper connecting plate 11, a first lower connecting plate 12, a first upper plate 13, a first lower plate 14, and a first upper connecting plate 11. It has a friction plate material (first friction plate material) 15, a first lower friction plate material (first friction plate material) 16, a first bearing pressure part 17, and a first shear bolt (first movement restraint part) 18. are doing.

The first upper connection plate member 11 is connected to the upper fixing portion A11. In other words, the first upper connection plate member 11 is connected to the seismic isolation upper structure A1 via the upper fixing portion A11.

The first upper connection plate member 11 is formed into a plate shape. The thickness direction of the first upper connection plate member 11 is directed in the up-down direction. The thickness of the first upper connection plate member 11 is constant across the axis O1 direction.

The first lower connection plate member 12 is formed into a plate shape. The first lower connecting plate 12 is arranged on the same axis O1 as the first upper connecting plate 11 and is spaced apart from the first upper connecting plate 11 on the +O1 side.

The thickness direction of the first lower connection plate member 12 is directed in the up-down direction. The thickness of the first lower connection plate member 12 changes along the axis O1 direction. The thickness of the first lower connecting plate 12 is formed so that it gradually becomes thicker as it approaches the first upper connecting plate 11. In other words, the thickness of the first lower connection plate member 12 is formed to gradually increase from the +O1 side to the -O1 side.

The upper surface 12u of the first lower connecting plate 12 is formed so as to gradually move upward from the +O1 side toward the -O1 side. The lower surface 12d of the first lower connecting plate member 12 is formed to gradually move downward from the +O1 side toward the -O1 side.

The first upper plate member 13 is disposed above the first upper connecting plate member 11 and the first lower connecting plate member 12 with a slight interval therebetween.

The thickness direction of the first upper plate material 13 faces in the up-down direction. The thickness of the first upper plate material 13 changes along the axis O1 direction. The thickness of the first upper plate member 13 is formed so as to gradually increase from the first upper connecting plate member 11 side toward the first lower connecting plate member 12 side. In other words, the thickness of the first upper plate member 13 is formed to gradually increase from the -O1 side to the +O1 side.

The lower surface 13d of the first upper plate 13 is formed substantially parallel to the upper surface 12u of the first lower connecting plate 12. The lower surface 13d of the first upper plate member 13 is formed so as to gradually move upward from the +O1 side toward the -O1 side.

The first lower plate member 14 is disposed below the first upper connecting plate member 11 and the first lower connecting plate member 12 with a slight interval therebetween.

The thickness direction of the first lower plate material 14 is directed in the up-down direction. The thickness of the first lower plate material 14 changes along the axis O1 direction. The thickness of the first lower plate member 14 is formed so as to gradually increase from the first upper connecting plate member 11 side toward the first lower connecting plate member 12 side. In other words, the thickness of the first lower plate member 14 is formed to gradually increase from the −O1 side toward the +O1 side.

The upper surface 14u of the first lower plate member 14 is formed substantially parallel to the lower surface 12d of the first lower connecting plate member 12. The upper surface 14u of the first lower plate member 14 is formed to gradually move downward from the +O1 side toward the -O1 side. The gap between the upper surface 14u of the first lower plate 14 and the lower surface 13d of the first upper plate 13 becomes gradually narrower from the -O1 side toward the +O1 side.

In plan view, the first upper plate 13 and the first lower plate 14 are formed wider than the first lower connecting plate 12 (see FIG. 2(b)). In other words, the length of the first upper plate member 13 and the first lower plate member 14 in the width direction T1 perpendicular to the axis O1 is longer than the length of the first lower connecting plate member 12 in the width direction T1. Both ends of the first upper plate member 13 and the first lower plate member 14 in the width direction T1 protrude beyond the first lower connecting plate member 12. The protruding portions of the first upper plate material 13 and the first lower plate material 14 are referred to as protruding portions 13a and 14a, respectively.

The first upper friction plate 15 is arranged between the first upper plate 13 and the first lower connection plate 12. The first upper friction plate member 15 is formed into a plate shape. The thickness direction of the first upper friction plate member 15 is oriented substantially in the vertical direction.

The first upper friction plate 15 is placed in contact with the lower surface 13d of the first upper plate 13. The first upper friction plate 15 is placed in contact with the upper surface 12u of the first lower connection plate 12.

The first lower friction plate 16 is arranged between the first lower connecting plate 12 and the first lower plate 14. The first lower friction plate member 16 is formed into a plate shape. The thickness direction of the first lower friction plate member 16 is oriented substantially in the vertical direction.

The first lower friction plate 16 is placed in contact with the lower surface 12d of the first lower connection plate 12. The first lower friction plate 16 is placed in contact with the upper surface 14u of the first lower plate 14.

The first bearing pressure portion 17 includes a collar (sheath tube) 17a, a bearing bolt 17b, a nut 17c, a washer 17d, a disc spring 17e, and a seat plate 17f. The first bearing pressure section 17 is configured by bolting the first upper plate material 13 and the first lower plate material 14 together via a disc spring 17e to maintain a predetermined distance between the first upper plate material 13 and the first lower plate material 14. The first upper plate member 13 and the first lower plate member 14 apply bearing pressure to the first lower connecting plate member 12 by holding the first lower connecting plate member 12 so as not to exceed the dimension.

Attachment holes 13h and 14h are formed in the overhanging portion 13a of the first upper plate 13 and the overhanging portion 14a of the first lower plate 14, respectively. A collar 17a is arranged from the attachment hole 13h of the first upper plate 13 to the attachment hole 14h of the first lower plate 14.

A bearing bolt 17b is inserted into the collar 17a from above. A nut 17c is fastened to the lower end of the bearing bolt 17b. A seat plate 17f is provided along the upper surface of the first upper plate 13 and the lower surface of the first lower plate 14. A washer 17d is attached between the upper part of the bearing bolt 17b and the seat plate 17f and between the nut 17c and the seat plate 17f. A disc spring 17e is provided between the washer 17d and the seat plate 17f. The collar 17a is in contact with seat plates 17f at both ends, and the seat plates 17f are pressed against the first upper plate 13 and the first lower plate 14 by disc springs 17e.

The first shear bolt 18 is inserted through the first upper plate 13, the first upper connection plate 11, and the first lower plate 14, and is fastened with a nut (not shown). This restricts movement of the first upper plate 13, the first upper connection plate 11, and the first lower plate 14 in the axis O1 direction and the width direction T1.

As shown in FIG. 2(d), at the time of an earthquake, a tensile force acts on the first friction damper device 1, and the relative displacement between the first upper connecting plate 11 and the first lower connecting plate 12 increases (separated from each other). ), the thicker portion of the first lower connecting plate 12 attempts to enter the smaller gap between the upper surface 14u of the first lower plate 14 and the lower surface 13d of the first upper plate 13. Therefore, the frictional force acting between the first upper plate 13 and the first lower plate 14 and the first lower connecting plate 12, that is, on the first upper friction plate 15 and the first lower friction plate 16, increases.

On the other hand, when a compressive force acts on the first friction damper device 1 and the relative displacement between the first upper connecting plate 11 and the first lower connecting plate 12 becomes small (they approach each other), the first upper connecting plate 13 Since the distance between the first lower connecting plate 14 and the first lower plate 14 is maintained, the thinner part of the first lower connecting plate 12 is connected to the upper surface 14u of the first lower connecting plate 14 and the lower surface 13d of the first upper plate 13. trying to enter the larger part of the gap. Therefore, the contact pressure on the friction surfaces between the first upper plate material 13 and the first lower plate material 14 and the first lower connecting plate material 12, that is, the first upper friction plate material 15 and the first lower friction plate material 16, becomes 0. , the friction force acting on the first upper friction plate 15 and the first lower friction plate 16 is almost eliminated.

FIG. 3 is a diagram showing the second friction damper device 2, in which (a) is a sectional view (vertical sectional view) taken along the line X3-X3 of (b), (b) is a plan view, and (c) is a sectional view taken along the line X3-X3 of (b). is a sectional view (vertical sectional view) taken along the line X4-X4 of (b), and (d) is a diagram showing the restoring force of the second friction damper device 2.
As shown in FIG. 3, the second friction damper device 2 includes a second upper connecting plate 21, a second lower connecting plate 22, a second upper plate 23, a second lower plate 24, and a second upper connecting plate 21. It has a plate material (second friction plate material) 25, a second lower friction plate material (second friction plate material) 26, a second bearing pressure part 27, and a second shear bolt (second movement restraint part) 28. ing.

The second upper connection plate member 21 is connected to the upper fixing portion A11. In other words, the second upper connection plate member 21 is connected to the seismic isolation upper structure A1 via the upper fixing part A11.

The second upper connection plate member 21 is formed into a plate shape. The thickness direction of the second upper connection plate member 21 is directed in the up-down direction. The thickness of the second lower connection plate member 22 changes along the axis O1 direction. The thickness of the second lower connecting plate 22 is formed so that it gradually becomes thicker as it is spaced apart from the second lower connecting plate 22. In other words, the thickness of the second upper connection plate member 21 is formed to gradually increase from the -O1 side to the +O1 side.

The upper surface 21u of the second upper connection plate member 21 is formed to gradually move upward from the -O1 side toward the +O1 side. The lower surface 21d of the second upper connection plate member 21 is formed so as to gradually move downward from the -O1 side toward the +O1 side.

The second lower connection plate member 22 is formed into a plate shape. The second lower connecting plate 22 is arranged on the same axis O1 as the second upper connecting plate 21, and is spaced apart from the second upper connecting plate 21 on the −O1 side. The plate thickness direction of the second lower connection plate member 22 faces in the up-down direction. The thickness of the second upper connection plate member 21 is constant across the axis O1 direction.

The second upper plate member 23 is arranged above the second upper connecting plate member 21 and the second lower connecting plate member 22 with a slight interval therebetween.

The thickness direction of the second upper plate member 23 faces in the up-down direction. The thickness of the second upper plate material 23 changes along the axis O1 direction. The thickness of the second upper plate material 23 is formed so as to gradually increase from the second upper connection plate material 21 side toward the second lower connection plate material 22 side. In other words, the thickness of the second upper plate member 23 is formed to gradually increase from the +O1 side to the -O1 side.

The lower surface 23d of the second upper plate member 23 is formed substantially parallel to the upper surface 21u of the second upper connecting plate member 21. The lower surface 23d of the second upper plate member 23 is formed to gradually move upward from the -O1 side toward the +O1 side.

The second lower plate member 24 is disposed below the second upper connecting plate member 21 and the second lower connecting plate member 22 with a slight interval therebetween.

The thickness direction of the second lower plate member 24 faces in the up-down direction. The thickness of the second lower plate material 24 changes along the axis O1 direction. The thickness of the second lower plate material 24 is formed to become gradually thicker from the second upper connecting plate material 21 side toward the second lower connecting plate material 22 side. In other words, the thickness of the second lower plate member 24 is formed to gradually increase from the +O1 side to the -O1 side.

The upper surface 24u of the second lower plate 24 is formed substantially parallel to the lower surface 21d of the second upper connection plate 21. The upper surface 24u of the second lower plate member 24 is formed to gradually move downward from the -O1 side toward the +O1 side. The gap between the upper surface 24u of the second lower plate 24 and the lower surface 23d of the second upper plate 23 becomes gradually narrower from the +O1 side toward the -O1 side.

In plan view, the second upper plate 23 and the second lower plate 24 are formed wider than the second upper connecting plate 21 (see FIG. 3(b)). In other words, the length of the second upper plate member 23 and the second lower plate member 24 in the width direction T1 perpendicular to the axis O1 is longer than the length of the second upper connecting plate member 21 in the width direction T1. Both ends of the second upper side plate material 23 and the second lower side plate material 24 in the width direction T1 protrude beyond the second upper connection plate material 21 . The projecting portions of the second upper plate material 23 and the second lower plate material 24 are defined as projecting portions 23a and 24a, respectively.

The second upper friction plate 25 is arranged between the second upper plate 23 and the second upper connection plate 21. The second upper friction plate member 25 is formed into a plate shape. The thickness direction of the second upper friction plate member 25 is oriented substantially in the vertical direction.

The second upper friction plate 25 is placed in contact with the lower surface 23d of the second upper plate 23. The second upper friction plate 25 is placed in contact with the upper surface 21u of the second upper connection plate 21.

The second lower friction plate 26 is arranged between the second upper connection plate 21 and the second lower plate 24. The second lower friction plate material 26 is formed into a plate shape. The thickness direction of the second lower friction plate member 26 is oriented substantially in the vertical direction.

The second lower friction plate 26 is placed in contact with the lower surface 21d of the second upper connection plate 21. The second lower friction plate 26 is placed in contact with the upper surface 24u of the second lower plate 24.

The second bearing pressure portion 27 includes a collar (sheath tube) 27a, a bearing bolt 27b, a nut 27c, a washer 27d, a disc spring 27e, and a seat plate 27f. The second bearing pressure portion 27 is configured by bolting the second upper plate material 23 and the second lower plate material 24 together via a disc spring 27e to maintain a predetermined distance between the second upper plate material 23 and the second lower plate material 24. The second upper plate member 23 and the second lower plate member 24 apply bearing pressure to the second upper connecting plate member 21 by holding the second upper connecting plate member 21 so as not to exceed the dimension.

Attachment holes 23h and 24h are formed in the overhanging portion 23a of the second upper plate material 23 and the overhanging portion 24a of the second lower side plate material 24, respectively, which penetrate in the vertical direction. A collar 27a is arranged from the attachment hole 23h of the second upper plate 23 to the attachment hole 24h of the second lower plate 24.

A bearing bolt 27b is inserted into the collar 27a from above. A nut 27c is fastened to the lower end of the bearing bolt 27b. A seat plate 27f is provided along the upper surface of the second upper plate 23 and the lower surface of the second lower plate 24. A washer 27d is attached between the upper part of the bearing bolt 27b and the seat plate 27f and between the nut 27c and the seat plate 27f. A disc spring 27e is provided between the washer 27d and the seat plate 27f. The collar 27a is in contact with seat plates 27f at both ends, and the seat plates 27f are pressed against the second upper plate 23 and the second lower plate 24 by disc springs 27e.

The second shear bolt 28 is inserted through the second upper plate 23, the second lower connection plate 22, and the second lower plate 24, and is fastened with a nut (not shown). As a result, movement of the second upper plate 23, the second lower connecting plate 22, and the second lower plate 24 in the direction of the axis O1 is restricted.

As shown in FIG. 3(d), during an earthquake, compressive force acts on the second friction damper device 2, and the relative displacement between the second upper connecting plate 21 and the second lower connecting plate 22 becomes smaller (they come closer together). Then, the thicker part of the second upper connecting plate 21 tries to enter the small gap between the upper surface 24u of the second lower plate 24 and the lower surface 23d of the second upper plate 23. Therefore, the frictional force acting between the second upper plate 23 and the second lower plate 24 and the second lower connection plate 22, that is, on the second upper friction plate 25 and the second lower friction plate 26, increases.

On the other hand, when a tensile force acts on the second friction damper device 2 and the relative displacement between the second upper connecting plate 21 and the second lower connecting plate 22 becomes large (separated), the second upper connecting plate 23 and Since the distance from the second lower plate material 24 is maintained, the gap between the upper surface 24u of the thinner second lower plate material 24 of the second upper connecting plate material 21 and the lower surface 23d of the second upper plate material 23 is maintained. Trying to get into the big part. Therefore, the surface pressure on the friction surfaces between the second upper plate material 23 and the second lower plate material 24 and the second lower connecting plate material 22, that is, the second upper friction plate material 25 and the second lower friction plate material 26, becomes 0, The friction force acting on the second upper friction plate 25 and the second lower friction plate 26 is substantially eliminated.

FIG. 4 is a diagram showing the history characteristics of the friction damper mechanism 100.
As shown in FIG. 4, in the friction damper mechanism 100 including the first friction damper device 1 and the second friction damper device 2, when the displacement of the first friction damper device 1 and the second friction damper device 2 increases, the friction force increases. increase During a small to medium earthquake in which the displacement of the first friction damper device 1 and the second friction damper device 2 is small, a small frictional force is generated. During a major earthquake in which the first friction damper device 1 and the second friction damper device 2 have large displacements, a large frictional force is generated. This allows the friction damper to be effective from small to large earthquakes.

In the friction damper mechanism 100 configured in this way, when a tensile force is applied to the first friction damper device 1 during an earthquake, the friction force acting on the first upper friction plate member 15 and the first lower friction plate member 16 increases. When compressive force is applied, the friction force acting on the first upper friction plate 15 and the first lower friction plate 16 is almost eliminated. When a compressive force acts on the second friction damper device 2 during an earthquake, the friction force acting on the second upper friction plate 25 and the second lower friction plate 26 increases, and when a tensile force acts on the second upper friction plate 25 And the frictional force acting on the second lower friction plate 26 is almost eliminated. Therefore, since the first friction damper device 1 and the second friction damper device 2 are arranged in parallel, a small friction force is generated during a small to medium earthquake where the axial displacement of the damper is small, and a small friction force is generated during a large earthquake where the axial displacement of the damper is large. During an earthquake, large frictional forces can be generated.

In addition, by installing the friction damper mechanism 100 on the base isolation layer, the increase in acceleration of the base-isolated building can be suppressed during small and medium-sized earthquakes where the displacement is small because the frictional resistance is small, and the frictional resistance increases during large earthquakes where the displacement is large. Displacement of the seismic isolation layer can be suppressed.

In addition, by installing the friction damper mechanism 100 between the layers of the damping structure, the increase in acceleration of the damping building can be suppressed during small and medium-sized earthquakes because the frictional resistance is small, and during large earthquakes, the frictional resistance is large, so fewer units can be used. Interlayer displacement can be reduced.

Further, since the friction damper mechanism 100 is an axial resistance type damper, the frictional resistance force does not change due to its own weight, unlike a sliding bearing.

Further, by adjusting the direction in which the friction damper mechanism 100 is installed, the frictional resistance force can be arbitrarily set corresponding to an arbitrary direction in the horizontal direction.

In addition, the friction damper mechanism 100 can function as a fail-safe because it exerts a large resistance force when a huge earthquake occurs.

(Second embodiment)
Next, a friction damper mechanism according to a second embodiment of the present invention will be explained using mainly FIGS. 5 to 9.
In the following actual machine embodiment, the same members as those used in the embodiment described above are given the same reference numerals, and the explanation thereof will be omitted.

FIG. 5 is a schematic diagram showing a friction damper mechanism according to a second embodiment of the present invention.
The friction damper mechanism 100A shown in FIG. 5 has one end connected to an upper fixing part A11 (see FIG. 1; the same applies hereinafter), and the other end connected to a lower fixing part A21 (see FIG. 1; the same applies below). . In this embodiment, the lower fixing part A22 is not provided, and the lower fixing part provided in the seismically isolated lower structure A2 is provided at one location A21.

In the axis O1 direction, the lower fixed part A21 side is defined as the +O1 side, and the upper fixed part A11 side is defined as the -O1 side. Further, the direction along the axis O1 is defined as the X direction, and the horizontal direction perpendicular to the X direction is defined as the Y direction. The direction corresponding to the +O1 side in the X direction is defined as the +X side, and the direction corresponding to the -O1 side in the X direction is defined as the -X side.

FIG. 6 is a vertical sectional view of the friction damper mechanism 100A, showing a case where the slider is in a neutral position without compressive force or tensile force acting on the piston rod.
As shown in FIG. 6, the friction damper mechanism 100A includes an outer cylinder (housing part) 3, a housing 4, an upper spring (upper biasing part) 46, a lower spring (lower biasing part) 47, It includes an upper shoe (upper member) 5, a lower shoe (lower member) 6, a piston rod 7, and a slider 8.

As shown in FIG. 5, the outer tube 3 has a rectangular tube shape. The axial direction of the outer tube 3, which has a rectangular tube shape, coincides with the axis O1. An opening 31 is formed at the -X side end of the outer cylinder 3.

A mounting portion 32 is provided at the +X side end of the outer cylinder 3. The mounting portion 32 is formed with a mounting hole 32h that penetrates in the vertical direction. The outer cylinder 3 is connected to the lower fixing part A21 via a connecting member (not shown) attached to the mounting hole 32h of the mounting part 32. In other words, the outer cylinder 3 is connected to the seismically isolated lower structure (the other of the upper structure and the lower structure) A2 via the lower fixing part A21.

As shown in FIG. 6, the upper plate portion 33 forming the upper surface 3u of the outer cylinder 3 is provided with an upper stopper 33a that projects downward. The upper stoppers 33a are provided at two locations spaced apart in the X direction.

The lower plate portion 34 forming the lower surface 3d of the outer cylinder 3 is provided with a lower stopper 34a that projects upward. The lower stoppers 34a are provided at two locations spaced apart in the X direction. The lower stopper 34a is arranged vertically below the upper stopper 33a.

The housing 4 is arranged inside the outer cylinder 3. The housing 4 has a cylindrical shape. The axial direction of the housing 4, which has a rectangular cylindrical shape, coincides with the axis O1. Both ends of the housing 4 in the X direction are open.

The upper plate part 41 arranged at the upper part of the housing 4 is arranged below the upper plate part 33 of the outer cylinder 3. The lower plate part 42 arranged at the lower part of the housing 4 is arranged above the lower plate part 34 of the outer cylinder 3. In other words, gaps are formed between the housing 4 and the outer tube 3 at the upper and lower portions, respectively.

The upper plate portion 41 of the housing 4 is provided with an upper locked portion 41a that projects upward. The upper locked portions 41a are provided at two locations spaced apart in the X direction.

The upper locked portion 41a can come into contact with the upper stopper 33a of the outer cylinder 3. The two upper locked portions 41a are arranged inside the two upper stoppers 33a. As a result, movement of the housing 4 is restricted between the two upper stoppers 33a of the outer cylinder 3.

The lower plate portion 42 of the housing 4 is provided with a lower locked portion 42a that projects downward. The lower locked portions 42a are provided at two locations spaced apart in the direction of the axis O1.

The lower locked portion 42a can come into contact with the lower stopper 34a of the outer cylinder 3. The two lower locked portions 42a are arranged inside the two lower stoppers 34a. As a result, movement of the housing 4 is restricted between the two lower stoppers 34a of the outer cylinder 3.

The upper spring 46 is provided between the upper plate part 33 of the outer cylinder 3 and the upper plate part 41 of the housing 4. The upper spring 46 biases the upper plate part 33 and the upper plate part 41 in a direction to separate them in the vertical direction.

The lower spring 47 is provided between the lower plate part 34 of the outer cylinder 3 and the lower plate part 42 of the housing 4. The lower spring 47 biases the lower plate portion 34 and the lower plate portion 42 in a direction to separate them in the vertical direction.

The upper shoe 5 is provided on the lower surface 41d of the upper plate portion 41 of the housing 4. The lower shoe 6 is provided on the upper surface 42u of the lower plate portion 42 of the housing 4. The lower shoe 6 is arranged below the upper shoe 5. The lower shoe 6 has a structure in which the upper shoe 5 is turned upside down.

The upper shoe 5 and the lower shoe 6 have a long shape in the X direction. Here, in the description of the upper shoe 5 and the lower shoe 6, the X direction (one horizontal direction) may be referred to as the length direction, and the Y direction (the other horizontal direction) may be referred to as the width direction.

FIG. 7 is a perspective view of the upper shoe 5 viewed diagonally from below.
As shown in FIG. 7, the lower part of the upper shoe 5 is provided with a first strip member 51a and a second strip member 51b.

The first strip member 51a is arranged at the center of the upper shoe 5 in the width direction (Y direction). The first strip member 51a is arranged on the +X side in the X direction.

The second strip member 51b is arranged on both sides of the first strip member 51a in the width direction (Y direction). The second strip member 51b is arranged on the −X side in the X direction.

A slight gap serving as an upper guide groove 53 is formed between the first strip member 51a and the second strip member 51b.

An upper inclined surface 52 is formed on the lower surface of the upper shoe 5. The upper inclined surface 52 has an inverted V shape when viewed from the Y direction. The upper inclined surface 52 is a sliding surface that slides on a slider 8, which will be described later.

The upper inclined surface 52 has a first upper inclined surface 52a and a second upper inclined surface 52b.

The first upper inclined surface 52a is formed on the lower surface of the first strip member 51a. The first upper inclined surface 52a is inclined with respect to the horizontal plane. The first upper inclined surface 52a is inclined gradually downward toward the +X side.

The second upper inclined surface 52b is formed on the lower surface of the second strip member 51b. The second upper inclined surface 52b is inclined with respect to the horizontal plane. The second upper inclined surface 52b is inclined gradually downward toward the −X side.

The direction of inclination of the first upper inclined surface 52a with respect to the horizontal plane and the direction of inclination of the second upper inclined surface 52b with respect to the horizontal plane are opposite directions. In this embodiment, the angle of inclination of the first upper inclined surface 52a with respect to the horizontal plane and the angle of inclination of the second upper inclined surface 52b with respect to the horizontal plane are substantially the same.

FIG. 8 is a perspective view of the lower shoe 6 and the slider 8 viewed diagonally from above, and the lower shoe 6 and the slider 8 are separated for explanation.
As shown in FIG. 8, the upper part of the lower shoe 6 is provided with a first strip member 61a and a second strip member 61b.

The first strip member 61a is arranged at the center of the lower shoe 6 in the width direction (Y direction). The first strip member 61a is arranged on the +X side in the X direction.

The second strip member 61b is arranged on both sides of the first strip member 61a in the width direction (Y direction). The second strip member 61b is arranged on the −X side in the X direction.

A slight gap serving as a lower guide groove 63 is formed between the first strip member 61a and the second strip member 61b.

A lower inclined surface 62 is formed on the upper surface of the lower shoe 6. The lower inclined surface 62 has a V-shape when viewed from the Y direction. The lower inclined surface 62 is a sliding surface that slides on a slider 8, which will be described later.

The lower inclined surface 62 has a first lower inclined surface 62a and a second lower inclined surface 62b.

The first lower inclined surface 62a is formed on the upper surface of the first strip member 61a. The first lower inclined surface 62a is inclined with respect to the horizontal plane. The first lower inclined surface 62a is inclined gradually upward toward the +X side.

The second lower inclined surface 62b is formed on the upper surface of the second strip member 61b. The second lower inclined surface 62b is inclined with respect to the horizontal plane. The second lower inclined surface 62b is inclined gradually upward toward the −X side.

The direction of inclination of the first lower inclined surface 62a with respect to the horizontal plane and the direction of inclination of the second lower inclined surface 62b with respect to the horizontal plane are opposite directions. In this embodiment, the angle of inclination of the first lower inclined surface 62a with respect to the horizontal plane and the angle of inclination of the second lower inclined surface 62b with respect to the horizontal plane are substantially the same.

The angle of inclination of the first upper inclined surface 52a with respect to the horizontal plane and the angle of inclination of the first lower inclined surface 62a with respect to the horizontal plane are substantially the same. The angle of inclination of the second upper inclined surface 52b with respect to the horizontal plane and the angle of inclination of the second lower inclined surface 62b with respect to the horizontal plane are substantially the same.

As shown in FIG. 6, the piston rod 7 is a rod-shaped member extending in the X direction. A mounting portion 71 is provided at the end of the piston rod 7 in the −X direction. The mounting portion 71 is formed with a mounting hole 71h that penetrates in the vertical direction. The piston rod 7 is connected to the upper fixing portion A11 via a connecting member (not shown) attached to the attachment hole 71h of the attachment portion 71. In other words, the piston rod 7 is connected to the seismically isolated upper structure (one of the upper structure and the lower structure) A1 via the upper fixing part A11.

The slider 8 is provided at the end of the piston rod 7 in the +X direction. The slider 8 is interposed between the upper shoe 5 and the lower shoe 6. The slider 8 is slidable in the X direction with respect to the upper shoe 5 and the lower shoe 6. The slider 8 has a substantially rectangular parallelepiped shape.

As shown in FIG. 8, an upper inclined surface 81 is formed on the upper surface of the slider 8. As shown in FIG. A friction material (not shown) is provided on the upper inclined surface 81. The upper inclined surface 81 is a sliding surface that slides on the upper shoe 5.

The upper inclined surface 81 has a first upper inclined surface 81a and a second upper inclined surface 81b.

The first upper inclined surface 81a is formed at the center of the slider 8 in the width direction (Y direction). The first upper inclined surface 81a is inclined with respect to the horizontal plane. The first upper inclined surface 81a is inclined gradually downward toward the +X side.

The second upper inclined surface 81b is formed on both sides of the first upper inclined surface 81a in the width direction (Y direction). The second upper inclined surface 81b is inclined with respect to the horizontal plane. The second upper inclined surface 81b is inclined gradually downward toward the −X side.

The direction of inclination of the first upper inclined surface 81a with respect to the horizontal plane and the direction of inclination of the second upper inclined surface 81b with respect to the horizontal plane are opposite directions. In this embodiment, the angle of inclination of the first upper inclined surface 81a with respect to the horizontal plane and the angle of inclination of the second upper inclined surface 81b with respect to the horizontal plane are substantially the same.

The direction and angle of inclination of the first upper inclined surface 81a with respect to the horizontal plane are substantially the same as the direction and angle of inclination of the first upper inclined surface 52a of the upper shoe 5 with respect to the horizontal plane. The first upper inclined surface 81a can be brought into close contact with the first upper inclined surface 52a.

The direction and angle of inclination of the second upper inclined surface 81b with respect to the horizontal plane and the direction and angle of inclination of the second upper inclined surface 52b of the upper shoe 5 with respect to the horizontal plane are substantially the same. The second upper inclined surface 81b can be in close contact with the second upper inclined surface 52b.

An upper guide portion 82 that projects upward is provided between the first upper inclined surface 81a and the second upper inclined surface 81b. The upper guide portion 82 is engaged with the upper guide groove 53 of the upper shoe 5. As a result, the slider 8 is guided to slide in the X direction with respect to the upper shoe 5, and displacement in other directions is restrained.

A lower inclined surface 86 is formed on the lower surface of the slider 8 . A friction material (not shown) is provided on the lower inclined surface 86. The lower inclined surface 86 is a sliding surface that slides on the lower shoe 6.

The lower inclined surface 86 has a first lower inclined surface 86a and a second lower inclined surface 86b.

The first lower inclined surface 86a is formed at the center of the slider 8 in the width direction (Y direction). The first lower inclined surface 86a is inclined with respect to the horizontal plane. The first lower inclined surface 86a is inclined gradually upward toward the +X side.

The second lower inclined surface 86b is formed on both sides of the first lower inclined surface 86a in the width direction (Y direction). The second lower inclined surface 86b is inclined with respect to the horizontal plane. The second lower inclined surface 86b is inclined gradually upward toward the −X side.

The direction of inclination of the first lower inclined surface 86a with respect to the horizontal plane and the direction of inclination of the second lower inclined surface 86b with respect to the horizontal plane are opposite directions. In this embodiment, the angle of inclination of the first lower inclined surface 86a with respect to the horizontal plane and the angle of inclination of the second lower inclined surface 86b with respect to the horizontal plane are substantially the same.

The direction and angle of inclination of the first lower inclined surface 86a with respect to the horizontal plane and the direction and angle of inclination of the first lower inclined surface 62a of the lower shoe 6 with respect to the horizontal plane are substantially the same. The first lower inclined surface 86a is in close contact with the first lower inclined surface 62a.

The direction and angle of inclination of the second lower sloped surface 86b with respect to the horizontal plane are substantially the same as the direction and angle of inclination of the second lower sloped surface 62b of the lower shoe 6 with respect to the horizontal plane. The second lower inclined surface 86b is in close contact with the second lower inclined surface 62b.

A lower guide portion 87 that projects downward is provided between the first lower inclined surface 86a and the second lower inclined surface 86b. The lower guide portion 87 is engaged with the lower guide groove 63 of the lower shoe 6. As a result, the slider 8 is guided to slide in the X direction with respect to the lower shoe 6, and displacement in other directions is restrained.

Next, the operation of the friction damper mechanism 100A will be explained.
FIG. 9 is an operation diagram of the friction damper mechanism 100A, in which (a) shows a case where a force is applied in the direction in which the piston rod 7 pops out from the outer cylinder 3, and (b) shows a case where the piston rod 7 is inside the outer cylinder 3. This shows the case where a force acts in the direction of entering. Note that FIGS. 9(a) and 9(b) are cross sections of a portion where the slider 8 slides on the upper shoe 5 and the lower shoe 6.
Normally, as shown in FIG. 6, the slider 8 is arranged at the center position in the X direction with respect to the upper shoe 5 and the lower shoe 6. The entire upper inclined surface 81 of the slider 8 (the first upper inclined surface 81a and the second upper inclined surface 81b) is the entire upper inclined surface 52 of the upper shoe 5 (the first upper inclined surface 52a and the second upper inclined surface 52b). ). The entire lower inclined surface 86 of the slider 8 (the first lower inclined surface 86a and the second lower inclined surface 86b) is the entire lower inclined surface 62 of the lower shoe 6 (the first lower inclined surface 62a and the second lower inclined surface 86b). It is in close contact with the surface 62b). The upper spring 46 urges the upper shoe 5 toward the slider 8, and the lower spring 47 urges the lower shoe 6 toward the slider 8.

In this state, when a tensile force is applied to the friction damper mechanism 100A between the upper fixed part A11 and the lower fixed part A21 during an earthquake, as shown in FIG. A force in the −X direction (force in the direction of moving away from the outer cylinder 3) is applied. As a result, the slider 8 provided on the piston rod 7 is pulled in the -X direction, and slides between the second upper inclined surface 81b of the slider 8 and the second upper inclined surface 52b of the upper shoe 5. As the movement occurs, sliding also occurs between the second lower inclined surface 86b of the slider 8 and the second lower inclined surface 62b of the lower shoe 6. On the other hand, there is a slight gap between the first upper inclined surface 81a of the slider 8 and the first upper inclined surface 52a of the upper shoe 5, and a first lower inclined surface 86a of the slider 8 is formed. A slight gap is created between the first lower inclined surface 62a of the lower shoe 6 and the first lower inclined surface 62a of the lower shoe 6.

As the amount of displacement of the piston rod 7 in the −X direction increases, the upper spring 46 and the lower spring 47 are pushed further, the repulsive force from the upper spring 46 and the lower spring 47 increases, and the frictional resistance force also increases.

On the other hand, when a compressive force is applied to the friction damper mechanism 100A between the upper fixed part A11 and the lower fixed part A21 during an earthquake, as shown in FIG. 9(b), the piston rod 7 is moved in the +X direction. A force (force in a direction approaching the outer cylinder 3) is applied. As a result, the slider 8 provided on the piston rod 7 is pushed in the +X direction, and sliding occurs between the first upper inclined surface 81a of the slider 8 and the first upper inclined surface 52a of the upper shoe 5. At the same time, sliding occurs between the first lower inclined surface 86a of the slider 8 and the first lower inclined surface 62a of the lower shoe 6. On the other hand, there is a slight gap between the second upper inclined surface 81b of the slider 8 and the second upper inclined surface 52b of the upper shoe 5, and the second lower inclined surface 86b of the slider 8 A slight gap is created between the lower shoe 6 and the second lower inclined surface 62b.

As the amount of displacement of the piston rod 7 in the +X direction increases, the upper spring 46 and the lower spring 47 are pushed further, the repulsive force from the upper spring 46 and the lower spring 47 increases, and the frictional resistance force also increases.

In the friction damper mechanism 100A configured in this way, when a tensile force is applied during an earthquake, the difference between the second upper inclined surface 81b of the slider 8 and the second upper inclined surface 52b of the upper shoe 5 is As the sliding occurs, sliding also occurs between the second lower inclined surface 86b of the slider 8 and the second lower inclined surface 62b of the lower shoe 6. When compressive force is applied during an earthquake, sliding occurs between the first upper inclined surface 81a of the slider 8 and the first upper inclined surface 52a of the upper shoe 5, and the first upper inclined surface 52a of the slider 8 Sliding occurs between the first lower inclined surface 86a and the first lower inclined surface 62a of the lower shoe 6. In both cases of tensile force and compressive force, as the amount of displacement increases, the frictional resistance force also increases, so small frictional force is generated during small to medium earthquakes where the damper's axial displacement is small, and during large earthquakes where the damper's axial displacement is large. Sometimes large frictional forces can be generated.

Next, the effect of the friction damper mechanism according to the embodiment shown above will be analyzed.
FIG. 10 is a diagram showing an analytical model.
As shown in FIG. 10, the analytical model is one in which a damper and a natural rubber support (horizontal stiffness k, damping constant h) are installed between an upper structure (mass W) and a lower structure. The damper was compared and verified between the friction damper mechanism (displacement-dependent friction damper) according to the embodiment shown above and a conventional hysteresis damper (conventional friction damper).
Note that the mass W of the upper structure is 4240×10 ³ kg. The horizontal stiffness k of the natural rubber bearing is 5.8×10 ³ kN/m, and the damping constant h is 2%.

Seismic waves for calculation are shown in Table 1.

L2 (Level 2 earthquake) shown in Table 1 refers to seismic motions that occur extremely rarely. L1 (Level 1 earthquake) is a medium-sized earthquake, and refers to seismic motion that is likely to occur at least once during the life of the structure. The seismic waves are as shown in FIG.

The restoring force of the displacement-dependent friction damper is as shown in FIG. 12(a). As the displacement increases, the frictional force also increases. Here, the frictional force at 50 cm is F ₅₀ =R ₅₀ ×W × g, and R ₅₀ =3%, 4%, 5%, 6%, and 7%. Further, the initial frictional force Fi=25%, 50%, and 75% of _F50 .

The restoring force of the conventional friction damper for comparison is as shown in FIG. 12(b). Frictional force is constant regardless of displacement. Here, in order to compare with the displacement-dependent friction damper, the maximum frictional force F _max is defined as the frictional force F ₅₀ of the displacement-dependent friction damper. Let F ₅₀ = R ₅₀ ×W × g, and R ₅₀ = 3%, 4%, 5%, 6%, 7%.

The relationship between the maximum response acceleration and R ₅₀ and the relationship between the maximum response displacement and R ₅₀ for each seismic wave are shown in FIGS. 13 to 18. In the legends of FIGS. 13 to 18, 25% change, 50% change, and 70% change are displacement-dependent friction dampers, and are 25%, 50%, and 70% of the initial friction force F _i =F ₅₀ , respectively. Conventional shows results for a conventional friction damper.

The following can be seen from FIGS. 13 to 18.
・In any seismic wave, regardless of the L1 or L2 level, for both conventional friction dampers and displacement-dependent friction dampers, the larger the R ₅₀ (=frictional force F _{50 /} gravity Wg), the larger the maximum response acceleration. . The larger _R50 , the smaller the maximum response displacement.
- The difference in maximum response acceleration between the conventional friction damper and the displacement-dependent friction damper is larger at the L1 level than at the L2 level. The smaller the initial friction force, the lower the maximum response acceleration. For small to medium-sized earthquakes at the L1 level, the maximum response acceleration of the displacement-dependent friction damper is smaller than that of the conventional friction damper, and the smaller the initial friction force, the greater the reduction rate.
- The difference in maximum response displacement between the conventional friction damper and the displacement-dependent friction damper is smaller at the L1 level than at the L2 level.

Therefore, it can be seen that the displacement-dependent friction damper can reduce the maximum response acceleration more than the conventional friction damper. Furthermore, it can be seen that the displacement-dependent friction damper has a higher acceleration reduction effect than the conventional friction damper for small to medium-sized earthquakes at the L1 level than for large earthquakes at the L2 level. Furthermore, it can be seen that the smaller the initial friction force, the greater the reduction rate of the maximum response acceleration in the displacement-dependent friction damper than in the conventional friction damper.

Note that the various shapes and combinations of the constituent members shown in the above-described embodiments are merely examples, and various changes can be made based on design requirements and the like without departing from the gist of the present invention.

For example, in the second embodiment shown above, the piston rod 7 of the friction damper mechanism 100A is connected to the upper fixing part A11, and the mounting part 32 of the outer cylinder 3 is connected to the lower fixing part A21. It is not limited to this. The piston rod may be connected to the lower structure, and the housing portion may be connected to the upper structure.

In addition, as a modification of the second embodiment, the first upper inclined surface of the upper shoe gradually slopes upward as it goes toward the +X side, and the second upper inclined surface of the upper shoe gradually slopes upward as it goes toward the -X side. Therefore, it gradually slopes upward, and as the first lower slope of the lower shoe moves towards the +X side, it gradually slopes downward, and as the second lower slope of the lower shoe moves towards the -X side. Therefore, it may be inclined gradually downward, and the sliding surface of the slider may be inclined so as to correspond to the sliding surfaces of the upper shoe and the lower shoe.

1 First friction damper device 2 Second friction damper device 3 Outer cylinder (housing part)
4 Housing 5 Upper shoe (upper member)
6 Lower shoe (lower part)
7 Piston rod 8 Slider 11 First upper connecting plate 12 First lower connecting plate 13 First upper plate 14 First lower plate 15 First upper friction plate (first friction plate)
16 First lower friction plate material (first friction plate material)
17 First bearing pressure part 18 First shear bolt (first movement restraint part)
21 Second upper connecting plate 22 Second lower connecting plate 23 Second upper plate 24 Second lower plate 25 Second upper friction plate (second friction plate)
26 Second lower friction plate material (second friction plate material)
27 Second bearing pressure part 28 Second shear bolt (second movement restraint part)
46 Upper spring (upper biasing part)
47 Lower spring (lower biasing part)
52 Upper inclined surface 52a First upper inclined surface 52b Second upper inclined surface 62 Lower inclined surface 62a First lower inclined surface 62b Second lower inclined surface 81 Upper inclined surface 81a First upper inclined surface 81b Second upper inclined surface 86 Lower inclined surface 86a First lower inclined surface 86b Second lower inclined surface 100 Friction damper mechanism 100A Friction damper mechanism

Claims (2)

A first friction damper device and a second friction damper device are arranged in parallel with each other between the upper structure and the lower structure,
The first friction damper device includes:
a first upper connection plate connected to the upper structure;
Disposed on the same axis as the first upper connecting plate and spaced apart from each other in the axial direction, connected to the lower structure, and formed so that the thickness in the vertical direction gradually increases as it approaches the first upper connecting plate. a first lower connecting plate material,
a first upper plate member disposed above the first upper connecting plate member;
a first lower plate member disposed below the first lower connecting plate member;
a first friction plate disposed between the first lower connection plate, the first upper plate, and the first lower plate;
Maintaining the distance between the first upper plate and the first lower plate so that it does not become less than a predetermined dimension, the first upper plate and the first lower plate apply bearing pressure to the first lower connecting plate. a first bearing pressure section that provides;
a first movement restraining portion that restrains movement of the first upper connecting plate, the first upper plate, and the first lower plate in the axial direction;
The second friction damper device includes:
a second lower connection plate member connected to the lower structure;
Disposed coaxially with the second lower connecting plate material and spaced apart from each other in the axial direction, connected to the upper structure, and formed so that the thickness in the vertical direction gradually increases as the distance from the second lower connecting plate material increases. a second upper connecting plate material,
a second upper plate member disposed above the second upper connecting plate member;
a second lower plate member disposed below the second lower connecting plate member;
a second friction plate disposed between the second upper connection plate, the second upper plate, and the second lower plate;
Maintaining the distance between the second upper plate and the second lower plate so that it does not become less than a predetermined dimension, and applying bearing pressure to the second upper connecting plate with the second upper plate and the second lower plate. a second bearing pressure section;
A friction damper mechanism comprising: a second movement restraining portion that restrains movement of the second lower connecting plate, the second upper plate, and the second lower plate in the axial direction. A friction damper mechanism installed between an upper structure and a lower structure,
a piston rod connected to one of the upper structure and the lower structure;
a casing connected to the other of the upper structure and the lower structure;
an upper member disposed inside the housing;
a lower member disposed below the upper member inside the casing;
a slider provided on the piston rod, interposed between the upper member and the lower member, and capable of sliding in one horizontal direction with respect to the upper member and the lower member;
an upper biasing portion that biases the upper member toward the slider;
a lower biasing portion that biases the lower member toward the slider,
The sliding surfaces of the slider and the upper member include a first upper inclined surface and a second upper inclined surface, both of which are along the horizontal direction and inclined in opposite directions with respect to the horizontal plane. arranged in parallel in the other horizontal direction perpendicular to the one horizontal direction,
The sliding surfaces of the slider and the lower member include a first lower inclined surface and a second lower inclined surface, both of which are along the other horizontal direction and inclined in opposite directions with respect to the horizontal plane. are arranged in parallel in the other horizontal direction.

Images