JP2008297727A - Seismic reinforcing structure of existing building - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To efficient control vibration by concentrating shear deformation, occurring in an existing building due to earthquakes, on a damper, without closing an opening or deteriorating a view from the opening. <P>SOLUTION: A lower end 61F of an angle 61 is fixed to a lower structure 20, and a column 30 is enclosed with the angle 61 in such a manner that a predetermined gap S is made between the angle 61 and a side surface of the existing column 30. A lower supporting member 60 is formed by combining the four angles 61 together. A side end 61E of the angle 61 is connected to another angle 61, and the lower supporting member 60 has a closed cross section. Similarly, an superstructural member 50 is fixed to superstructure 10 in such a manner as to surround the column 30, and the damper 40 for absorbing seismic energy is arranged between the upper and lower supporting members 50 and 60. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a seismic strengthening structure for an existing building that seismically reinforces an existing building.

  The method of seismic reinforcement of existing buildings is to place steel braces as reinforcements diagonally between existing columns and load bearing walls as reinforcements at the openings of existing columns and beams. In general, a method of increasing the thickness of an existing bearing wall, a method of increasing the cross section of an existing column or beam, and the like are generally used.

  However, the method of increasing the thickness of the existing bearing wall and the method of increasing the cross-section of the existing columns and beams are significant renovation work of the building, and there are problems of cost and construction period. The method of placing steel braces and the method of installing bearing walls are relatively easy, but steel braces run diagonally through the openings and the view from the window is damaged, and the openings are blocked by the bearing walls. As a result, the field of view is obstructed and the comfort level is reduced.

  Therefore, Patent Document 1 proposes a method in which a reinforcing bracket is interposed at a joint position where a column and a beam are joined without using a steel brace or a bearing wall, and the reinforcing bracket is joined to the column and the beam with an anchor material. ing.

In this patent document 1, since the steel brace and the bearing wall are not used, the problem that the scenery from an opening part is impaired or the opening part itself is obstruct | occluded, and comfortability falls is solved.
However, in the method described in Patent Document 1, the joint of the column beam is less deformed at the time of the earthquake, and even if this position is reinforced, the vibration damping effect of the building is small. Furthermore, there exists a subject that a reinforcement metal fitting only gives rigidity, and there is no energy absorption effect.
Japanese Patent Laid-Open No. 10-331437

  In view of the above-described facts, the present invention has an object to concentrate a shear deformation generated in an existing building due to an earthquake on a damper without blocking an opening or damaging a landscape from the opening, and to efficiently suppress vibration. .

  The invention according to claim 1 is disposed between the upper structure and the lower structure, and is provided between the upper structure and the lower structure in a seismic reinforcement structure that seismically reinforces an existing building. It is characterized by having a damper arranged around a column, and fixing means for fixing the damper to the upper structure and the lower structure.

In the first aspect of the present invention, the damper is disposed between the upper structure and the lower structure, and is fixed to the upper structure and the lower structure by the fixing means. The damper is deformed with the relative displacement of to suppress the existing building.
Moreover, since the damper is disposed so as to surround the pillar, the existing building can be seismically reinforced without blocking the opening and without damaging the scenery from the opening.

  According to a second aspect of the present invention, the fixing means has an upper end fixed to the upper structure, a closed section upper support member surrounding the column with a predetermined gap, and a lower end fixed to the lower structure. A lower support member having a closed cross section surrounding the column with a predetermined gap, and joining a lower end of the upper support member and an upper end of the damper, and an upper end of the lower support member and the damper. It is characterized by joining the lower end.

  The invention described in claim 2 is configured to surround an existing column with a damper, an upper support member, and a lower support member with a predetermined gap. At this time, high rigidity can be obtained in two horizontal directions by making the upper support member and the lower support member have a closed cross-sectional shape.

For this reason, the upper support member and the lower support member can behave rigidly independently of the deformation of the column, and the deformation can be concentrated on the damper.
Further, when the column is tilted by a large earthquake, the upper support member is received by the lower support member, and the building can be prevented from collapsing.

The invention described in claim 3 is characterized in that the upper support member and the lower support member are made of steel plates, and end portions are joined to form a closed cross section.
In the invention according to claim 3, since the upper support member and the lower support member are made of steel plates and the end portions are joined to form a closed cross section, the rigidity in two horizontal directions is increased.

The invention described in claim 4 is characterized in that the damper is composed of a plurality of steel plates facing the side surface of the column with a predetermined gap.
The invention according to claim 4 is a configuration in which a plurality of steel plates are arranged around the column with a predetermined gap from the side of the column, and the shear energy generated by the earthquake is absorbed and attenuated while the steel plate is plastically deformed. Let For this reason, the shear energy applied to the column is reduced. In addition, the construction is simple and the construction is easy.

The invention described in claim 5 is characterized in that the damper is composed of a plurality of viscoelastic members facing the side surface of the column with a predetermined gap.
The invention according to claim 5 is a configuration in which a plurality of viscoelastic members are opposed to each other around a column with a predetermined gap from the side surface of the column. It absorbs and attenuates while the viscoelastic member it has is deformed. For this reason, the shear energy applied to the column is reduced. In addition, the construction is simple and the construction is easy.

  Since this invention set it as the said structure, the shear deformation which arises in the existing building by an earthquake can be concentrated on a damper, and can be efficiently damped, without blocking an opening part or impairing the scenery from an opening part.

(First embodiment)
The earthquake-proof reinforcement structure (hereinafter referred to as the earthquake-proof reinforcement structure) of the existing building according to the present invention will be described with reference to FIGS.
As shown in FIGS. 1 and 2, the seismic reinforcement structure 90 includes an existing pillar 30 between an upper structure 10 composed of a ceiling slab or a beam and a lower structure 20 composed of a floor slab or a beam. It is the structure which surrounds and reinforces.

A lower end 61 </ b> F of the angle 61 is fixed to the floor surface of the lower structure 20 with an anchor bolt 65.
The angle 61 has a shape corresponding to the side shape of the pillar 30, and two or more (four in FIG. 1) angles 61 are combined to form the lower support member 60.

In addition, the angle 61 is formed of a steel plate and is disposed so as to surround the column 30 from the periphery with a gap S between the column 30 and the column 61.
The side end portion 61E of the angle 61 is connected to the side end portion 61G of the adjacent angle 61, and the lower support member 60 has a closed cross section.
An upper end 51 </ b> F of the angle 51 is fixed to the ceiling surface of the upper structure 10 with an anchor bolt 55.

The angle 51 has a shape corresponding to the side shape of the pillar 30, and two or more (four in FIG. 1) angles 51 are combined to form the upper support member 50.
In addition, the angle 51 is formed of a steel plate, and is disposed so as to surround the column 30 from the periphery with a gap S between the column 30 and the column 51.
The side end 51E of the angle 51 is connected to the side end 51G of the adjacent angle 51 (not shown), and the upper support member 50 has a closed cross section.

Between the upper end portion of the lower support member 60 and the lower end portion of the upper support member 50, a damper 40 that absorbs and attenuates seismic energy while being deformed is disposed.
As shown in FIGS. 3A and 3B, the damper 40 is composed of four steel plates, and is disposed with a predetermined gap S from the side surface of the pillar 30.

The lower end of the damper 40 is joined to the upper end of the lower support member 60, and the upper end is joined to the lower end of the upper support member 50.
The material of the damper 40 is preferably a low yield point steel such as LYP225, for example, because it is necessary to absorb seismic energy in two horizontal directions by plastic deformation of the damper 40 and suppress shaking of the building.

Also, the mounting position of the damper 40 is such that when the building is shaken by an earthquake, the bending moment generated at the ends of the upper support member 50 and the lower support member 60 is evenly distributed without being biased. It is desirable to place it at approximately the center.
The vertical length of the damper 40 is desirably about 1/10 to 1/30 of the floor height.

  However, since the required damping characteristics vary depending on the structure of the building and the magnitude of the assumed earthquake, the material of the damper 40 is not limited to the low yield point steel, and the mounting position and length of the damper 40 are not limited. The present invention is not limited to the above, and an optimal material, size, position, etc. may be selected according to the existing building that is the target of seismic reinforcement.

  In addition, in FIG. 1, the configuration in which the four dampers 40 are arranged corresponding to the rectangular pillars has been described. However, when the pillar 30 has a circular cross-sectional shape, the dampers 40 have a cylindrical shape, and the pillars 30 are It is only necessary to surround the pillar 30 with a predetermined gap S. Even if the pillar 30 has another cross-sectional shape, the shape of the damper 40 is determined according to the cross-sectional shape, and the pillar 30 is surrounded with a predetermined gap S. That's fine.

At this time, the lower support member 60 and the upper support member 50 may be divided into two or more according to the cross-section (side surface) shape of the column 30, manufacturing, construction conditions, or the like.
That is, in FIG. 1, the lower support member 60 and the upper support member 50 are divided into four as a flat plate configuration, but may be divided into two as a flat plate is formed in an angle shape.

Furthermore, the lower support member 60 and the upper support member 50 have high rigidity against deformation in two horizontal directions at the time of an earthquake and behave rigidly independently of the deformation of the column. A general steel material is used, and a closed section is formed with a predetermined gap S from the column 30.
Thereby, the upper support member 50 and the lower support member 60 can behave rigidly independently of the deformation of the column 30, and the shear deformation can be concentrated on the damper 40.

Next, the effect | action of the earthquake-proof reinforcement structure 90 is demonstrated using FIG.
4 (A), 4 (B), and 4 (C) show the behavior of the pillar 30 during an earthquake, and FIGS. 4 (D), 4 (E), and 4 (F) show the seismic reinforcement structure 90 in the event of an earthquake. The behavior of the pillar 30 and the damper 40 is shown. Hereinafter, the comparison will be described.

  Before the earthquake, the pillar 30 in FIG. 4A and the pillar 30 in FIG. 4D, the damper 40, the upper support member 50, and the lower support member 60 are left and right between the upper structure 10 and the lower structure 20. It is in a stationary state without deformation.

Next, the case where a relative displacement occurs between the upper structure 10 and the lower structure 20 will be described on the assumption that the upper structure 10 is stationary for convenience.
As shown in FIG. 4B, the lower structure 20 moves (displacement amount ΔB) in the X direction while deforming the column 30 during an earthquake. The displacement amount ΔB is determined by the X-direction seismic force F acting on the column 30 and the horizontal rigidity of the column 30. At this time, the resistance force R ₀ generated inside the pillar 30 is balanced with the seismic force F.

On the other hand, as shown in FIG. 4E, when the seismic reinforcement structure 90 is arranged around the pillar 30, the lower structure 20 moves in the X direction (displacement amount) while deforming the pillar 30 and the damper 40 at the time of the earthquake. ΔE). The displacement amount ΔE is determined by the force (FQ) obtained by subtracting the resistance force Q of the damper 40 from the X-direction seismic force F acting on the column 30 and the damper 40 and the horizontal rigidity of the column 30. At this time, the resistance force R ₁ generated inside the pillar 30 is balanced with (FQ). As the resistance force Q of the damper 40 acts, the force (FQ) applied to the column 30 is reduced, and the displacement amount ΔE of the lower structure 20 is smaller than the displacement amount ΔB.

That is, the existing building can be damped by absorbing the energy of the damper 40.
At this time, by providing the lower support member 60 and the upper support member 50 with high rigidity, these support members are hardly deformed, and the shear deformation is concentrated on the damper 40 to efficiently absorb the seismic energy. it can.

Since the damper 40 surrounds the side surface of the pillar 30 and is arranged in the periphery, the existing building can be damped not only in the X direction but also in the horizontal two directions.
Since a gap S is provided between the pillar 30 and the damper 40, the deformation can be concentrated on the damper 40 as shown in FIG.

  Next, a case where an earthquake that exceeds the allowable limit of shear deformation of the pillar 30 acts on the existing building will be described.

As shown in FIG. 4C, when the displacement amount ΔC in the X direction due to the seismic force F exceeds the allowable limit of shear deformation of the column 30, a crack 13 is generated in a part of the column 30, and the column 30 is damaged. Begins.
On the other hand, as shown in FIG. 4 (F), for the above-mentioned reason, with the same seismic force F, the displacement amount ΔF of the column 30 is smaller than the displacement amount ΔC and has not yet reached the allowable limit of shear deformation. That is, it is possible to prevent the pillar 30 from being damaged and to have a vibration control effect on the existing building even for a larger-scale earthquake.

  Even in the event that a greater earthquake occurs and the pillar 30 is damaged, the seismic reinforcement structure 90 surrounds the pillar 30 and the upper support member 50 is received by the lower support member 60, preventing collapse. .

Next, an example of the verification result of the seismic reinforcement structure 90 will be described with reference to FIGS.
The model building 100 used for the verification of the vibration damping effect is as shown in the long side direction axis group diagram of FIG. 5 and the short side direction axis group diagram of FIG. And it is an RC building consisting of towers.

  The height between the layers of the model building 100 is 4 m higher on the first basement floor and the first floor above the ground, and 3.85 m from the second floor to the fifth floor. The columns, including the columns located on the outer wall, are arranged in five rows at intervals of 9.3 m, 8 m, 8 m, and 9 m in the long side direction, and intervals of 7.7 m, 7.7 m, 4.3 m, and 3.4 m in the short side direction. Are arranged in 5 rows (partially 4 rows).

  In the verification method, the seismic response analysis was performed in the state where the seismic reinforcement structure 90 is not disposed in the model building 100 and in the state where the seismic reinforcement structure 90 is disposed. The input ground motion was 3 earthquakes (EL CENTRO NS, FAFT EW, HACHINOH NS) used as standard in building structure design.

The response analysis result is evaluated by calculating the horizontal two-direction movement amount of each layer of the model building 100 due to three earthquakes, and dividing the calculated movement amount by the interlayer distance (floor height). Was evaluated by the value of the interlayer deformation angle.
In other words, it is evaluated that if the interlaminar deformation angle is reduced by arranging the seismic reinforcement structure 90, the horizontal movement of the layer due to the earthquake can be suppressed, and it can be said that the damping effect can be objectively supported.

As for the response analysis results, the vertical axis represents the number of layers of the model building 100 and the horizontal axis represents the interlayer deformation angle, and the calculation results for each of the three earthquake waves are illustrated.
First, in order to grasp the characteristics of the model building 100, a response analysis was performed without the seismic reinforcement structure 90 being arranged.

  As a result, as shown in FIG. 9A, it can be seen that the interlayer deformation angle is larger in the order of the first floor and the second floor, and the movement amount of the layer in this portion is large. This tendency was the same for all seismic waves. FIG. 9A shows the analysis result in the short side direction (see FIG. 6) in which the amount of movement of the layer is calculated to be larger.

  In addition, among the three earthquake waves, the maximum value of the interlayer deformation angle was caused by EL CENTRO NS on any floor. The maximum interlayer deformation angle in EL CENTRO NS is 0.0097 (rad) as the first-layer interlayer deformation angle.

  This is because the pillars on the lower floors of the building bear a larger building weight, and in the event of an earthquake, they receive a horizontal shearing force in proportion to their weight. In addition, since it is a store, there are many openings on the outer wall of the first floor. For this reason, it is considered that the interlayer deformation angle on the first floor is the largest.

  Next, since it was understood that the first floor interlayer deformation angle was the largest and then the second floor interlayer deformation angle was the largest, as a reinforcement method for the model building 100, the first floor pillar and the second floor pillar were seismic resistant. A reinforcing structure 90 is arranged. Under the condition that the seismic reinforcement structure 90 is disposed on the first-floor pillar and the second-floor pillar, response analysis was performed by inputting the same three earthquake waves.

  The location of the seismic retrofit structure 90 is a building on the first floor excluding the pillars constituting the outer wall from the five columns arranged in the long side direction, as shown in the floor plan of the first floor in FIG. A total of six columns composed of three columns in the interior and two columns in the building excluding the columns constituting the outer wall among the five columns arranged in the short side direction.

Also on the second floor, the arrangement of the pillars is basically the same as that on the first floor, and there are six pillars at positions corresponding to the pillar positions on the first floor.
In addition, as shown in FIG. 8, the material 40 of the damper 40 used for the response analysis was a low yield point steel (LYP225, plate thickness 9 mm), and the dimensions were 200 × 1000 mm. The material of the upper support member 50 and the lower support member 60 was a general steel plate (SS400, plate thickness 18 mm), and the dimensions of one side were 1000 mm. In addition, the dimension of one side of the pillar 30 is 450 mm, and the height is about 3000 mm.

  As a result, as shown in Fig. 9 (B), the inter-layer deformation angle is greatly reduced in all three earthquakes centering on the 1st and 2nd floors, and the existing building has a damping effect. I was able to.

    Specifically, the inter-layer deformation angle on the first floor, which was 0.0097 (rad) at the maximum before the placement of the seismic reinforcement structure 90, becomes 0.003 (rad) at the maximum after the placement of the seismic reinforcement structure 90. About 1/3. Furthermore, the interlayer deformation angles on other floors are also reduced.

  As described above, the interlayer deformation angle can be reduced by selecting the material and dimensions of the damper 40 in the seismic reinforcement structure 90 to the optimum values. In other words, in the seismic reinforcement of existing buildings, the allowable limit of the interlayer deformation angle is determined, and the conditions such as the material, length, thickness, and arrangement position of the damper 40 are selected so as to be within the allowable limit range. The required vibration control effect can be provided.

  In this embodiment, the material of the damper 40 is a low yield point steel, but it is not necessary to limit the material to a low yield point steel as long as it is a member for absorbing seismic energy. Alternatively, the damper 40 may be formed by forming a predetermined gap S around the column 30 having a rectangular cross section and facing each other.

(Second Embodiment)
FIG. 10 shows the second embodiment.
In the second embodiment, the damper 40 that absorbs the seismic force in the seismic reinforcement structure 90 has four oil dampers 70A, 70B, 70C, and 70D, and one end is provided on each of the lower brackets 75F and 75G and the upper brackets 76H and 76I. It is the structure which attached. All other components are the same as those in the first embodiment, and the description of the same parts is omitted.

  In order to give strength to the lower brackets 75F and 75G, a thick steel plate is formed in an L shape, and the corners of the lower support member 60 and the corners of the lower support member 60 are located at two opposite corners of the upper end of the lower support member 60. The upper end of the lower support member 60 and the lower end of the lower bracket 75 are fixed so as to coincide with the character-shaped corners.

  The upper brackets 76H and 76I are also formed in a L-shape with thick steel plates in order to give the same strength. The upper brackets 76H and 76I are formed at two opposite corners of the upper support member 50 at the corners of the upper support member 50. The L-shaped corners are aligned and the lower end of the upper support member 50 and the upper end of the upper bracket 76 are fixed.

  Note that the lower brackets 75F and 75G are arranged at the upper ends of the corners of the lower support member 60 that are opposite to the corners of the upper support member 50 at the two corners of the upper support member 50 that fix the upper brackets 76H and 76I. There are no corners.

The cylinder part of the oil damper 70A is attached to the upper part of one side surface of the lower bracket 75F, and the cylinder part of the oil damper 70C is attached to the upper part of the other side surface.
Further, the cylinder portion of the oil damper 70B is attached to the upper portion of one side surface of the lower bracket 75G, and the cylinder portion of the oil damper 70D is attached to the upper portion of the other side surface.

On the other hand, the rod part of the oil damper 70A is attached to the lower part of the side surface on one side of the upper bracket 76H, and the rod part of the oil damper 70B is attached to the upper part of the other side surface.
Further, the rod portion of the oil damper 70C is attached to the lower portion of the side surface on one side of the upper bracket 76I, and the rod portion of the oil damper 70D is attached to the upper portion of the other side surface.

  Here, the oil dampers 70A, 70B, 70C, and 70D may be commercially available products, and the rod portions of the oil dampers 70A, 70B, 70C, and 70D and the upper brackets 76H and 76I are attached to the rod portions. It is attached with the attachment member 92 using the pin hole which exists. Further, the cylinder portions of the oil dampers 70A, 70B, 70C, and 70D and the lower brackets 75F and 75G are attached by using an attachment member 94 using a pin hole provided in the cylinder portion.

Next, the effect | action by the above-mentioned structure is demonstrated.
Prior to the occurrence of the earthquake, the oil dampers 70A, 70B, 70C, and 70D are not expanded and contracted in the state shown in FIGS.

  During an earthquake, the shear deformation due to the earthquake is concentrated on the oil dampers 70A, 70B, 70C, and 70D disposed between the upper support member 50 and the lower support member 60 for the reason described above. At this time, the oil dampers 70A, 70B, 70C, 70D arranged in the place directly receiving the tensile force or compressive force due to the shear deformation absorb the shear force due to the earthquake while being expanded and contracted by the tensile force or compressive force, respectively. Suppresses vibration.

  For convenience, the case where the lower structure 20 is displaced in the X direction by an earthquake, the upper structure 10 remains stationary, and a relative displacement occurs between the upper structure 10 and the lower structure 20 will be described as an example. .

  Since the lower support member 60 has high rigidity, the lower support member 60 is displaced in the X direction by almost the same amount as the lower structure 20, and the upper support member 50 has high rigidity, so that it is substantially stationary with the upper structure 10. Accordingly, the relative displacement generated between the upper structure 10 and the lower structure 20 is efficiently transmitted to the oil dampers 70A and 70D.

  At this time, since the oil damper 70A is attached to the upper support member 50 via the upper bracket 76H and to the lower support member 60 via the lower bracket 75F, the oil damper 70A receives a relative displacement with a tensile force.

  On the other hand, since the oil damper 70D is attached to the upper support member 50 via the upper bracket 76I and to the lower support member 60 via the lower bracket 75G, the oil damper 70D receives relative displacement with a compressive force.

  Therefore, a force is applied to the oil damper 70A to increase the distance between the pin hole position of the rod portion of the oil damper 70A and the pin hole position of the cylinder portion, and the rod of the oil damper 70D is applied to the oil damper 70D. A force acts to reduce the distance between the pin hole position of the part and the pin hole position of the cylinder part.

  At this time, the piston disposed inside the oil damper 70A attempts to move in a direction that expands by receiving a tensile force, while the oil filled inside acts in a direction that prevents movement of the piston. For this reason, seismic energy is absorbed by the resistance of oil, and an increase in relative displacement between the upper structure 10 and the lower structure 20 is suppressed.

  On the other hand, the piston arranged inside the oil damper 70D tends to move in a direction in which it is contracted by receiving a compressive force. On the other hand, the oil filled inside acts in a direction that hinders the movement of the piston. For this reason, seismic energy is absorbed by the resistance of oil, and an increase in relative displacement between the upper structure 10 and the lower structure 20 is suppressed.

When the lower structure 10 moves in the opposite direction, the forces received by the oil dampers 70A and 70D by the relative displacement are in the opposite directions, acting in a form in which the tensile force and the compression force are switched, and the upper structure 10 and the lower structure 10 An increase in relative displacement with respect to the structure 20 is suppressed.
As a result, the existing building can be controlled.

  In addition, since the oil dampers 70A, 70B, 70C, and 70D are arranged around the pillar 30 with a predetermined gap S3 from the side face of the pillar 30, the seismic force in two horizontal directions as well as the X direction is provided. Absorbs and can dampen existing buildings.

  Further, in the seismic reinforcement structure 90, the damper 40 that absorbs the seismic energy is the oil dampers 70A, 70B, 70C, 70D, so that it can be used repeatedly, a commercially available product can be used, and the performance is stable. , 76I and the lower brackets 75F and 75G can be easily attached and detached, so that an effect such as easy maintenance can be expected.

It is a figure which shows the earthquake-proof reinforcement structure of the existing structure which concerns on the 1st Embodiment of this invention. It is principal part explanatory drawing which shows the earthquake-proof reinforcement structure of the existing structure which concerns on the 1st Embodiment of this invention. It is explanatory drawing which shows the earthquake-proof reinforcement structure of the existing structure which concerns on the 1st Embodiment of this invention. It is explanatory drawing which shows the effect | action of the earthquake-proof reinforcement structure of the existing structure which concerns on the 1st Embodiment of this invention. It is an axis set figure of the long side direction of a model building used for verification of the effect of the earthquake-proof reinforcement structure of the existing structure concerning a 1st embodiment of the present invention. It is an axis set figure of the short side direction of a model building used for verification of the effect of the earthquake-proof reinforcement structure of the existing structure concerning a 1st embodiment of the present invention. It is a floor plan of the 1st floor of the building used for verification of the effect of the earthquake-proof reinforcement structure of the existing structure concerning the 1st embodiment of the present invention. It is a figure which shows the earthquake-proof reinforcement structure of the existing structure which concerns on the 1st Embodiment of this invention used for effect verification. It is a figure which shows the effect verification result of the earthquake-proof reinforcement structure of the existing structure which concerns on the 1st Embodiment of this invention. It is a figure which shows the earthquake-proof reinforcement structure of the existing structure which concerns on the 2nd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Upper structure 20 Lower structure 30 Column 40 Damper 50 Upper support member 60 Lower support member 90 Seismic reinforcement structure

Claims (5)

In the seismic reinforcement structure that is arranged between the upper structure and the lower structure and seismically strengthens existing buildings,
A damper disposed around a column provided between the upper structure and the lower structure;
Fixing means for fixing the damper to the upper structure and the lower structure;
A seismic reinforcement structure for an existing building, characterized by comprising: The fixing means has an upper support member with a closed cross section that is fixed at the upper end to the upper structure and surrounds the pillar with a predetermined gap therebetween.
The lower end is fixed to the lower structure, and is composed of a lower support member having a closed cross section surrounding the column with a predetermined gap,
The seismic reinforcement structure for an existing building according to claim 1, wherein the lower end of the upper support member and the upper end of the damper are joined, and the upper end of the lower support member and the lower end of the damper are joined. The seismic reinforcement structure for an existing building according to claim 2, wherein the upper support member and the lower support member are made of steel plates, and end portions are joined to form a closed cross section. The seismic reinforcement structure for an existing building according to claim 2, wherein the damper is composed of a plurality of steel plates facing the side surfaces of the pillar with a predetermined gap. The seismic reinforcement structure for an existing building according to claim 2, wherein the damper is composed of a plurality of viscoelastic members facing the side surface of the column with a predetermined gap.

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