JPH09273163A - Earthquake resistant reinforcing method of existing building - Google Patents

Abstract

PROBLEM TO BE SOLVED: To greatly remote earthquake resistance through safe and simple repairing work without damaging in outward appearance of the existing building. SOLUTION: Brackets 4 and 5 are mounted to both up and down positions of a column 1 of a building, a floor slab between both of them is equipped with through-holes in which temporary posts 7 are inserted, and temporary bearing jacks 6 and the temporary posts 7 are inserted between two brackets 4 and 5. Reaction force is borne on the brackets 4 and 5, axial force acting on the column 1 is borne on the temporary posts 7 and temporary bearing jacks 6, and a part of the column 1 between two brackets 4 and 5 is cut off. A vibration isolation bearing 9 and a column end bearing jack 10 are inserted in the part in series, the column end bearing jack 10 is operated, and load of the column 1 is borne on the vibration isolation bearing 9. The column end bearing jack 10 is fixed and, at the same time, the temporary bearing jacks 6, temporary posts 7 and brackets 4 and 5 are removed. Such stages of work are applied to every column 1 of the building, and the whole upper structure of the building is borne on the vibration isolation bearing 9.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for repairing an existing building having insufficient seismic resistance to one having sufficient seismic resistance, and in particular, the upper structure of the building is provided with seismic isolation bearings. The present invention relates to a method for seismic retrofitting of an existing building with a structure supported by

[0002]

2. Description of the Related Art Most existing buildings are designed to have seismic performance based on predetermined standards. However, the design standards of buildings have been reviewed several times in the past, and the earthquake resistance has been revised to be more strict. For this reason, some of the products designed based on the old standards have structural weaknesses such as lack of reinforcing bars in the columns when compared with the current standards. Such buildings can be damaged by a large-scale earthquake. In contrast,
It is almost impossible to rebuild all existing buildings with insufficient seismic resistance immediately, and a method of improving seismic resistance by renovation is being considered. As such a method, for example, a method of reinforcing the column from the outside, a method of adding a diagonal member or the like to reinforce the entire structure, and the like have been proposed.

[0003]

However, the method of reinforcing the entire structure or structural members as described above has the following problems. When a member is added to the upper structure or a column member is reinforced, the repair work covers a wide range of the building, costs a lot, and significantly deteriorates the appearance of the building. Therefore, the function as a building is reduced and the value is reduced.

The present invention has been made in view of the above problems, and an object thereof is to make the earthquake resistance of an existing building significantly improved by a safe and simple repair work. It is to provide a reinforcing method.

[0005]

[Means for Solving the Problems] In order to solve the above problems, in the method for earthquake-proofing reinforcement of an existing building according to claim 1, a step of attaching brackets to two upper and lower positions of a pillar of the building, A step of inserting a temporary support jack between the brackets attached at two places so that at least a part of the jack reaction force is applied to the bracket, and a load acting on the pillar is supported by the temporary support jack; , The step of cutting the post between the positions where the two brackets are attached, the step of inserting the seismic isolation bearing and the jack for supporting the post end vertically in the cut part of the post, and the post of the post It includes a step of operating the supporting jack to support the load carried by the column on the seismic isolation bearing, and a step of removing the temporary supporting jack and the bracket.

According to a second aspect of the present invention, in the method for earthquake-proofing reinforcement of an existing building according to the first aspect, in the step of attaching the bracket, two steel members are brought into contact with two opposite side surfaces of a column, The two steel members are connected by a PC steel material arranged outside the cross section of the column, and a tension force is introduced into the PC steel material to press the steel member against the side surface of the column.

According to a third aspect of the present invention, in the method for earthquake-proofing reinforcement of an existing building according to the first aspect, the step of attaching the bracket to a side surface of a pillar is performed by forming a hole in the side surface of the pillar. A cap nut is embedded, and the bracket is fixed with a bolt screwed into the cap nut.

According to a fourth aspect of the present invention, in the method for earthquake-proofing reinforcement of an existing building according to the first aspect, an end plate arranged in a horizontal direction, and vertically rising from this end plate,
An end reinforcing material provided with a standing plate provided so as to surround the side surface of the pillar is attached to the end portion of the pillar where a part is cut off,
A step of filling and hardening a filler between the end face of the pillar in the standing plate and the end plate is included.

According to a fifth aspect of the present invention, in the seismic retrofitting method for an existing building according to the first aspect, the brackets attached to two places are attached to different floors, and between the two brackets. The method includes a step of providing a through-hole for inserting a temporary support jack or a temporary support in an existing floor slab.

According to a sixth aspect of the invention, in the seismic retrofitting method for the existing building according to the first aspect, the ends of the columns after cutting off a part of the columns are connected to adjacent columns by beams or floor slabs. The process shall be included.

The seismic retrofitting method of the existing building having the above structure is
It can be applied to any building of reinforced concrete structure, steel frame structure, and steel frame reinforced concrete structure. And each process of Claim 1 is performed for all the pillars of one building, may be sequentially performed for each one pillar, or may be performed for each group of several pillars. It may be divided and sequentially performed, or may be performed collectively for all the pillars. The jack for supporting the column end, which is installed so as to overlap with the above-mentioned seismic isolation bearing, is to be used permanently after repair, and it is desirable that the stroke of the jack can be fixed. For example, a jack having a structure that supports a load by using fluid pressure, and uses a curable material such as resin as the fluid.

[Operation] Since the invention according to the present application includes the above steps, it operates as follows. In the seismic retrofitting method for an existing building described in claim 1, since brackets are attached to upper and lower two places of the pillars, and the load carried by the pillars is supported by the temporary support jacks interposed therebetween, It is possible to cut the pillar between two brackets. At this time, since at least a part of the reaction force of the temporary support jack is applied to the bracket, a large load does not act on the beam joined to the pillar, and even if there is a load due to the building being used, it is sufficient. Safety is maintained.

Further, after a part of the column is cut off, a post-supporting jack is inserted into this part together with the seismic isolation bearing. Therefore, the stroke of the jack is adjusted to load the temporary supporting jack. Can be transferred to the above-mentioned pillar end supporting jack. At this time, since it is possible to transfer the load without pushing up the pillars above the excised portion upwards, even if the above steps are performed for some of the pillars of one building, it will be With no additional stress, the safety of each member is maintained. Therefore, seismic isolation bearings can be installed sequentially for each pillar, and repairs can be performed with a small construction. In addition, the safety during the renovation work is improved, and the renovation can be done while the building is in service.

Since the seismic isolation bearings are inserted in all the columns as described above, relative displacement is allowed between the upper part and the lower part, and the seismic force transmitted to the upper part is reduced.
Further, the damping force or the restoring force can be imparted by appropriately designing the seismic isolation device or by mounting an appropriate device between the upper part and the lower part.

In the seismic retrofitting method for an existing building described in claim 2, a steel bracket is arranged outside the cross section of the pillar.
Since it is fastened by the C steel material and fixed by strongly pressing it against the side surface of the column, it is not necessary to provide a through hole or the like in the cross section of the column, and there is no loss in the cross section of the column. Therefore, the bracket can be safely attached even to a column of reinforced concrete / steel frame reinforced concrete or a column of steel frame having a small cross section.

According to the seismic retrofitting method of the existing building described in claim 3, since the bracket is fixed by the bolt screwed into the cap nut inserted into the column, the column is made of reinforced concrete or steel reinforced concrete. The bracket can be fixed with a bolt, and the force acting on the bracket due to the shearing force of the bolt is transmitted to the column.

In the seismic retrofitting method for an existing building as claimed in claim 4, the end plates are arranged so as to be horizontal so as to face the cut surface of the pillar, and the standing plates raised from the end plates are arranged. Since it is attached so as to surround the end of the pillar, the end reinforcement when a part of the concrete pillar is cut off is effectively performed.
Therefore, when the seismic isolation bearing is inserted in the part where the column is cut off to support the axial force of the column, the safety against splitting is sufficiently ensured.

In the seismic retrofitting method for an existing building described in claim 5, the brackets installed at two upper and lower locations are installed on different floors of the building, and the load acting on the pillar is supported between these brackets. Since the temporary columns and jacks are arranged with the through holes in the floor slabs on the floors between them, they support the axial force of the columns without applying any load to the beams on this floor, and the beams on this floor. A portion of the post can be excised near the top or bottom of the column. And seismic isolation bearings can be placed in this part to create a seismic isolation structure.

In the seismic retrofitting method for an existing building according to claim 6, since the end portion after cutting off a part of the pillar is connected to the adjacent pillar by a beam or floor slab, the seismic isolation structure It is possible to prevent the sectional force of the column from becoming excessive with respect to the seismic force. In addition, it becomes possible to effectively protect the seismic isolation device against a fire or the like.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to the drawings. FIG. 1, FIG. 2 and FIG. 3 are schematic diagrams showing each step of the method for earthquake-proofing reinforcement of an existing building, which is one embodiment of the present invention. This method is carried out in the following steps.

First, as shown in FIG. 1 (a), two brackets 4 and 5 are fixed to the pillar 1b of the lower floor of the existing building and the pillar 1a of the floor immediately above the existing building to fix the floor of the floor immediately above. The floor slab 2 is provided with a through hole, and the temporary support jack 6 and the temporary support column 7 are inserted between the upper and lower brackets. And
A load is introduced into the jack 6 so that the temporary supporting jack 6 and the temporary support 7 bear the axial force acting on the pillar 1a.
As a result, it is possible to make a state in which almost no axial force acts on the column 1a between the two brackets 4 and 5. The pillar 1 of this building is made of reinforced concrete, and the brackets 4 and 5 have the structure shown in FIG. The bracket 4 has four steel members 41, 42, 43, and 44 that are respectively brought into contact with the four side surfaces of the pillar 1, and opposing steel members are arranged along both side surfaces of the pillar 1. It is connected and tightened by the PC steel material 45. Thereby, the steel member is strongly pressed against the side surface of the pillar 1 and fixed to the pillar.

Also, four steel members 41, 42, 43, 4
4 are superposed on other steel members adjacent to each other at their ends, and are superposed in a cross-beam shape surrounding the pillar 1, so that the force in the vertical direction can be transmitted to the adjacent members. . As shown in FIG. 5, each of the above steel members is constructed by assembling plate members by welding and joining in the horizontal direction and the vertical direction, and has sufficient rigidity and strength. The surface of the steel member 41 that is pressed against the side surface of the column is provided with irregularities to prevent sliding in the vertical direction, and a thickness of about 20 mm is provided between the steel member and the side surface of the column. The high strength mortar 46 is filled. As the unevenness, for example, one having mesh-like unevenness as shown in FIG. 6 or one in which wire rods are welded vertically and horizontally as shown in FIG. 7 can be adopted. In addition, depending on the state of the side surface of the pillar,
The steel member may be directly pressed against the side surface of the column without using the high-strength mortar.

When the axial force acting on the column 1 as described above is borne by the temporary column 7 and the temporary supporting jack 6 via the brackets 4 and 5, as shown in FIG. For example, the upper pillar of the floor immediately above is cut off. The excision of the pillar is
For example, it can be performed by cutting concrete, rebar, and steel frame using a diamond cutter or the like.

At this time, the corners of the cut ends of the pillars are easily cracked, and when the pillars are supported by seismic isolation bearings, a reaction force generates a horizontal tensile force at the ends of the pillars. The ends are easily cracked. In order to prevent this, it is desirable to reinforce the ends, and the reinforcement can be performed as shown in FIG. 8, for example. This reinforcing method uses the end reinforcing member 8 having an end plate 81 arranged in the horizontal direction and a standing plate 82 standing upright from the end plate 81 in the vertical direction. Is provided so as to surround the end of the pillar 1. In addition, a plurality of stud dowels 83 are attached to the upper surface of the end plate 81, and are overlapped with the rebar 1c left uncut so as to project from the end surface of the pillar 1, and a non-shrinkable high-strength mortar 84 is provided between them. Is filled. It should be noted that depending on the magnitude of the load acting on the pillar, the standing plate of the end reinforcing material can be omitted as shown in FIG. Alternatively, as shown in FIG. 10, the reinforcing bar 1c may be directly welded to the upper surface of the end plate 85 without providing the stud dowel.

FIG. 11 is a diagram showing another example of the method of attaching the end reinforcing material. The end reinforcing material 86 used in this method is erected on the end plate 87 as in the case shown in FIG. Board 88
However, the standing plate 88 is provided so as to form a gap with the side surface of the column 1. And FIG.
As shown in FIG. 1 (a), an uncured epoxy resin 89 is put inside the container-shaped standing plate 88, and this is fitted to the end portion of the pillar 1, and as shown in FIG. 11 (b). The end plate 8
The epoxy resin is filled between the end surface of the column 7 and the end surface of the pillar 1 and between the standing plate 88 and the side surface of the pillar to be cured. Instead of the above epoxy resin, another resin, cement-based grout material, or the like that can be handled in a liquid state and that has a high strength when cured can be used.

When the column is cut and the end portion is reinforced as described above, the seismic isolation bearing 9 and the flat jack 10 are inserted into the cut portion as shown in FIG. 2 (a). As shown in FIG. 12, the seismic isolation bearing 9 includes steel plates 91 and 92 arranged vertically, and a rubber material 93 arranged between them.
In order to prevent the rubber material 93 from being excessively deformed, a plurality of reinforcing plates 94 embedded in the rubber material 93 in the horizontal direction and a lead columnar member embedded in the central portion of the rubber material 93. The main part is composed of 95 and. In the seismic isolation bearing 9 as described above, the rubber material 93 supports the load in the vertical direction, and the deformation of the rubber material 93 causes the upper and lower steel plates 9 to move.
Allowing relative displacement in the horizontal direction between 1 and 92. Further, the lead columnar member 95 imparts a damping force to the relative motion between the upper and lower steel plates. The seismic isolation bearing is not limited to the structure as described above, but supports the vertical load by inserting spheres or cylinders in the upper and lower steel plate surfaces, or fixes the rails to the upper and lower steel plates respectively. However, it is possible to use seismic isolation bearings of various structures such as those which are arranged so that they are at right angles and in which an intermediate support that can roll or slide along both rails is interposed. .

The flat jack 10 is mainly composed of a bag-shaped member made of steel, and a fluid can be press-fitted therein. This bag-shaped member is formed into a flat shape, and there are shapes such as a circular shape, a rectangular shape, and an elliptical shape.
The gap between the bag-shaped upper plate and the lower plate is expanded to push up the upper structure or to bear the load from the upper structure. Also, by selecting a fluid that presses into and shrinks without shrinkage, it is possible to support the upper structure permanently.
In this embodiment, an uncured epoxy resin is used as the fluid.

The epoxy resin is press-fitted into the flat jack 10 by using a press-fitting pump 11 as shown in FIG. 2 (b) or FIG. 12, which causes the flat jack 10 to expand in the vertical direction. Bear the load of the superstructure acting on 1. Flat jack 1 in this state
The 0 pressure inlet is blocked and the epoxy resin is hardened to permanently support the load of the upper structure on the seismic isolation bearing 9. Along with this, the temporary columns 7 and the temporary supporting jacks 6 are in a state in which no load is applied, and these and the brackets 4 and 5 can be removed, and the ends of the columns are supported by the seismic isolation bearing 9 as shown in FIG. The structure can be

By performing such a process basically for all columns on the same floor of the building, the entire upper structure of the building is supported by seismic isolation bearings, and the horizontal force transmitted to the upper structure during an earthquake. Can be reduced, and a structure with less shaking and excellent earthquake resistance can be obtained. In addition, as for the floor where the seismic isolation bearing is inserted in this way, the first floor is generally suitable, but depending on the structure of the building, it may be inserted on the basement floor or the upper floors of two or more floors. You may insert it on the floor.

FIG. 13 is a schematic view showing another embodiment of the invention according to the present application, and FIG. 13 (a) shows the seismic isolation on the top of the pillar 1a on the lower floor, that is, immediately below the beam 3a on the floor immediately above. Seismic isolation is provided by installing bearings. In this case, the brackets 104 and 105 are provided on the upper floor and the lower floor, and the temporary support column 107 and the temporary support jack 106 are inserted between them, so that the existing building is isolated as in the above embodiment. Can be quake. Moreover, FIG.13 (b) provides a seismic isolation bearing in the middle part of the pillar 1a of a specific floor. In this embodiment, the brackets 204 and 205 are attached to the upper and lower parts of the pillar 1a of the target floor portion, and the load of the pillar 1a is applied to the temporary pillar 20 without providing a hole penetrating the floor slab.
7 and the temporary support jack 206. Then, the existing building can be seismically isolated by the same process as that of the embodiment described above.

FIG. 14 shows an example in which a building having a sufficient floor-to-ceiling height on the first floor has seismic isolation by inserting seismic isolation bearings at the lower ends of columns on the first floor. In this embodiment, a seismic isolation bearing 309 is inserted at the lower end of the pillar 1 on the first floor by the same process as the seismic retrofit method shown in FIGS. 1 to 3. After doing this for all the columns, the beam 303 and the floor slab 3 are joined so as to be joined to the upper part of the part to which the seismic isolation bearing 309 is attached, that is, the end part where the part of the column 1 is cut off.
02 is provided to form a new floor. In such a seismic retrofitting method, the newly installed floor and the beam 3 and floor slab 2 on the first floor are seismic isolation floors that allow relative displacement in the horizontal direction, and the lower end of the pillar 1 is a beam 303. -Being connected by the floor slab 302, it is possible to prevent a large cross-sectional force from being generated in the column 1 even when a horizontal force is applied during an earthquake.
Also, in case of fire, seismic isolation bearings will be used for the existing floor slab 2
And the newly installed floor slab 302 protects it and improves fire resistance.

The embodiment described above is for the case where the columns are reinforced concrete or steel frame reinforced concrete, but also when the columns are steel frames, a seismic isolation structure can be formed by inserting seismic isolation bearings by the same process. . FIG. 15 is a front view, a side view, and a plan view showing a state in which the bracket 404 is attached to the steel frame column 401. The bracket 404 used here has a shape similar to that of the bracket shown in FIG. 4, but the steel frame column 401 can be provided with a through hole more easily than concrete, and is a PC for tightening a steel member. It is also possible to arrange so that a part of the steel material penetrates the cross section of the column.

Further, in FIG. 16, a plurality of bolt holes are provided in the steel frame column 501, and the bracket 502 can be fixed by the bolts 503 inserted through the bolt holes. FIG. 16 is a schematic front view and a schematic diagram showing an example thereof. It is a top view. By fixing the bracket 502 with the bolts 503 in this way, the shape and size of the bracket 502 can be reduced, and the bracket 502 can be easily attached. On the other hand, even for columns of reinforced concrete or steel reinforced concrete,
By embedding a cap nut 601 as shown in FIG. 17 on the side surface of the pillar, the bracket can be fixed with bolts. The cap nut 601 is fitted in a hole formed in the side surface of the pillar, and a material having a large adhesive force such as epoxy resin is filled between the outer surface of the cap nut and the inner surface of the hole 602 to firmly fix the cap nut. is there.

[0034]

As described above, in the seismic retrofitting method for an existing building according to the present invention, brackets are attached to upper and lower two places of a pillar, and the pillar is provided with a temporary pillar and a temporary supporting jack interposed therebetween. Since the seismic isolation bearing is attached while supporting the load acting on the building, a large load does not act on the beam joined to the column, and sufficient safety is maintained even if there is a load due to the building being used. can do. Moreover, even if the temporary support and the temporary support jack are loaded with a load and the seismic isolation bearing is inserted, the load of the column is transferred to the state where the seismic isolation bearing bears without pushing the column upward. Therefore, even if the seismic isolation bearing is inserted for each pillar in sequence, no additional stress acts on the beam or pillar, and the safety of each member is maintained. Therefore, it can be repaired by a small-scale construction, and can also be repaired to a seismic isolation structure while the building is in service. Further, the brackets can be attached to different floors, and the temporary support columns and the temporary support jacks can be arranged by providing through holes in the floor slab, and the seismic isolation bearings can be inserted and attached at arbitrary positions of the columns.

[Brief description of drawings]

FIG. 1 is a schematic diagram for explaining each step of a method for earthquake-proofing reinforcement of an existing building which is an embodiment of the invention according to the present application.

FIG. 2 is a schematic diagram for explaining each step of the method for earthquake-proofing reinforcement of an existing building which is one embodiment of the invention according to the present application.

FIG. 3 is a schematic diagram for explaining each step of the method for seismic retrofitting of an existing building, which is an embodiment of the present invention.

FIG. 4 is a front view, a side view and a plan view of a bracket used in the method described in FIGS. 1 to 3;

5 is a cross-sectional view of the bracket shown in FIG.

6 is a schematic view showing a contact surface of the bracket shown in FIG. 4 with a pillar.

FIG. 7 is a schematic view showing a contact surface with a column for another bracket that can be used instead of the bracket shown in FIG.

FIG. 8 is a schematic cross-sectional view showing a method of reinforcing the end surface where the column is cut out in the seismic retrofitting method shown in FIGS. 1 to 3.

FIG. 9 is a schematic cross-sectional view showing another example of the method of reinforcing the end surface where the column is cut out in the seismic retrofit method shown in FIGS. 1 to 3.

FIG. 10 is a schematic cross-sectional view showing another example of the method of reinforcing the end surface where the column is cut off in the seismic retrofit method shown in FIGS. 1 to 3.

FIG. 11 is a schematic cross-sectional view showing another example of the method of reinforcing the end surface where the column has been cut off in the seismic reinforcement method shown in FIGS. 1 to 3.

FIG. 12 is a schematic view showing a structure of a seismic isolation bearing and a flat jack used in the seismic strengthening method shown in FIGS. 1 to 3.

FIG. 13 is a schematic view showing another embodiment of the invention according to the present application.

FIG. 14 is a schematic view showing another embodiment of the invention according to the present application.

FIG. 15 is a front view, a side view, and a plan view showing a state where a bracket is attached to a steel frame column.

FIG. 16 is a schematic front view and a schematic plan view showing another example of the bracket attached to the steel frame pillar.

FIG. 17 is a schematic cross-sectional view showing a mounting state of a cap nut for fixing a bracket to a concrete pillar with a bolt.

[Explanation of symbols]

1,401,501 Pillar 2 Floor slab 3 Beam 4,104,204,404 Bracket 5,105,205 Bracket 6,106,206 Temporary support jack 7,107,207 Temporary post 8 End reinforcement 9,309 Seismic bearing 10 Flat jack (post end support jack) 11 Press-fitting pump 41, 42, 43, 44 Steel member 45 PC steel material 46 High strength mortar 81, 85, 87 End plate 82, 88 Stand plate 83 Stud dowel 84 High strength Mortar 91,92 Steel plate 93 Rubber material 94 Reinforcement plate 95 Lead columnar member 502 Bracket 503 Bolt 601 Cap nut

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[Procedure amendment]

[Submission date] September 5, 1996

[Procedure amendment 1]

[Document name to be amended] Drawing

[Correction target item name] All figures

[Correction method] Change

[Correction contents]

FIG.

[Figure 3]

[Fig. 2]

FIG. 4

[Figure 5]

FIG. 6

FIG. 7

[Figure 8]

[Figure 9]

FIG. 10

FIG. 11

FIG.

FIG. 16

FIG.

FIG. 13

FIG. 14

FIG.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hideki Ueda 4-13 Arakicho, Shinjuku-ku, Tokyo Sumitomo Construction Co., Ltd.

Claims (6)

[Claims] 1. A step of attaching brackets to upper and lower two places of a pillar of a building, and a provisional supporting jack is inserted between the brackets attached to upper and lower two places so that at least a part of the jack reaction force is The steps of applying the load to the bracket and supporting the load acting on the pillar on the temporary support jack, cutting the pillar between the positions where the two brackets are attached, A step of vertically interposing the bearing and a jack for supporting the pillar end, a step of operating the jack for supporting the pillar end to support the load borne by the pillar on the seismic isolation bearing, and the jack for temporary support And a step of removing the bracket, and a method for earthquake-proofing the existing building. 2. The seismic retrofitting method for an existing building according to claim 1, wherein in the step of attaching the bracket, two steel members are brought into contact with two opposite side surfaces of a column, and a PC is arranged outside the column cross section. A method for seismic retrofitting an existing building, characterized in that the two steel members are connected by a steel material, and a tension force is introduced into the PC steel material to press the steel member against a side surface of a column. 3. The method for seismic retrofitting an existing building according to claim 1, wherein the step of attaching the bracket to a side surface of a pillar includes forming a hole in the side surface of the pillar, and embedding a cap nut in the hole. A method for seismic retrofitting an existing building, characterized in that the bracket is fixed with a bolt screwed into a nut. 4. The seismic retrofitting method for an existing building according to claim 1, wherein the end plate is arranged in a horizontal direction, and is vertically erected from the end plate so as to surround the side surface of the column. An end reinforcing material provided with a standing plate is attached to the end of the pillar, a part of which is cut off, and a filling material is filled between the end surface of the pillar and the end plate in the standing plate to cure. A method for seismic retrofitting an existing building, characterized by including the step of: 5. The method for seismic retrofitting an existing building according to claim 1, wherein the brackets installed at two locations are installed on different floors, and are temporarily attached to a floor slab existing between the two brackets. A method for seismic retrofitting an existing building, comprising the step of providing a through hole through which a supporting jack or a temporary support is inserted. 6. The method for earthquake-proofing reinforcement of an existing building according to claim 1, characterized by including a step of connecting an end portion after cutting off a part of a pillar to an adjacent pillar with a beam or floor slab. Seismic retrofitting method for existing buildings.