JP3820498B2 - Seismic isolation method for existing buildings - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention belongs to the technical field of a seismic isolation method for retrofitting an existing building to a seismic isolation structure.
[0002]
[Prior art]
Conventionally, various seismic isolation methods for renovating existing buildings to seismic isolation structures have been proposed.
(1) For example, the seismic isolation method for an existing building described in Japanese Patent Application Laid-Open No. 2-20767 (Patent No. 2596798) by the applicant of the present invention is to root the basement of the foundation part of the existing building and This is a construction method in which a permanent steel column that is exposed instead of a support pile is built and a seismic isolation device is installed between the steel column and the underground structure of an existing building.
[0003]
(2) The seismic isolation method for an existing building described in Japanese Patent Application Laid-Open No. 8-338155 is to install a jack device that supports the upper structure above the seismic isolation layer of the existing building, and to cut the column at the seismic isolation layer. Then, after pushing up the upper structure above the seismic isolation layer of the existing building with a jack device, installing the seismic isolation device on the column, lowering the upper structure and connecting the upper and lower columns via the seismic isolation device It is.
[0004]
(3) The seismic isolation method for an existing building described in Japanese Patent Application Laid-Open No. 10-115104 is that a temporary support is installed around the pillar in the seismic isolation layer of the existing building, and then the pillar is cut and the pillar is cut. Attach a cap to the end face of the door and insert the seismic isolation device between them. In the seismic isolation device, a restraining member that restrains the displacement in the horizontal direction is installed between the upper and lower mounting plates.
[0005]
(4) The seismic isolation method for existing buildings described in Japanese Patent Application Laid-Open No. 9-100644 is to reinforced steel with steel plates around the columns in the seismic isolation layer of existing buildings, and then reinforce them with concrete. This is a method of cutting and inserting and installing seismic isolation devices.
[0006]
[Problems to be solved by the present invention]
The above-mentioned (1) seismic isolation method requires securing a large underground work space in the foundation of the existing building, and constructing mountain retaining walls and excavation work. It is difficult to reduce the construction cost.
The seismic isolation method described in (2) above can be implemented by providing a seismic isolation layer in the middle layer of an existing building, but the upper structure of the building above the seismic isolation layer is pushed up and supported by multiple jack devices. Therefore, it requires a very large jack equipment, restricts the conditions under which it can be carried out, and has a problem in maintaining safety.
[0007]
The seismic isolation method described in (3) above can also be implemented by providing a seismic isolation layer in the middle layer of an existing building. However, a temporary support that supports the axial force of the column is approached around the column. Normally, the support is installed upright between the beams on the upper and lower floors. However, the presence of such a support has various drawbacks that interfere with the seismic isolation work for the column.
[0008]
The seismic isolation method described in (4) above can also be carried out by providing a seismic isolation layer in the middle layer of the existing building. Since curing is necessary until strength is developed, construction in a short construction period is not possible. In addition, the cost of steel-in-the-wall concrete and the steel sheet that goes to the pillar in preparation for its construction increases. Since the construction method is based on the premise that steel plates are used, the scope of application is limited for buildings where this is not permitted. And the pillar whose diameter is increased by the increased concrete also restricts the indoor space.
An object of the present invention is to provide a seismic isolation method for an existing building that can be carried out at a low construction cost and with a simplified work content.
[0009]
[Means for Solving the Problems]
As means for solving the above-mentioned problems, the seismic isolation method for an existing building according to the invention described in claim 1 is a method for renovating an existing building to a seismic isolation structure.
A stage to transmit and support the axial force borne by the seismic isolation pillar of the existing building to other pillars by the suspension structure,
Excising the seismic isolation device mounting position of the column;
Installing a seismic isolation device at the excision site;
A step of attaching a stopper plate that bears a horizontal force at the time of an earthquake to the pillar in an arrangement straddling the excision site of the pillar vertically,
Thereafter, loosening the suspension structure and transmitting the axial force borne by the pillar to the seismic isolation device;
In the same manner, the method includes the steps of installing seismic isolation devices on all the columns of the seismic isolation layer and then removing the stopper plate.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
The seismic isolation method for an existing building according to the invention described in claim 1 is a construction method that enables a seismic isolation structure to be repaired at an intermediate layer of the building, and is implemented as follows.
[0011]
First, as shown in FIG. 1 and FIG. 2, the axial force borne by the seismic isolation pillar 1 in the seismic isolation layer of the existing building is transmitted to other pillars 2 by the suspension structure. Support. In the illustrated suspension structure, connectors 3 (steel materials) are respectively attached to the lower part of the upper floor portion of the pillar 1 where the seismic isolation device is installed and the upper parts of the plurality of pillars 2 around it, and the PC steel wire 4 is connected between the upper and lower connectors. It is structured to be tightly coupled. The connector 3 is attached by an insert anchor or the like. FIG. 2 shows the plan layout. The number and direction of the PC steel materials 4 are not limited to the illustrated example, and are appropriately arranged according to the load and the proof stress. Instead of the PC steel wire 4, a suspension material can be selected according to the magnitude of the axial force to be borne and the material strength, and a steel material or the like can be used. Although not shown in the drawings, it is also preferable to incorporate tensioning means such as a jack in each PC steel wire 4 so as to facilitate adjustment of the tensioning force, and its introduction and release operations.
[0012]
FIG. 1 also shows a stage where the seismic isolation device mounting portion 5 of the pillar 1 is cut out over a necessary length range. The pillar 1 is cut horizontally using, for example, a wire saw. The range of excision is approximately the range of the height of the seismic isolation device.
First, a seismic isolation device mounting plate (detailed illustration is omitted) is horizontally mounted on the upper and lower end faces of the pillar 1 excised as described above. Between the plate and the cut end surface of the column, an epoxy resin is filled to stabilize the level and the fixing state. After that, the seismic isolation device 6 is inserted and installed between the upper and lower seismic isolation device mounting plates as shown in FIG.
[0013]
Further, as shown in FIG. 4, a stopper plate 7 that bears a horizontal force during an earthquake under construction is attached to the periphery of the column 1 so as to straddle the cut portion 5 of the column 1. The stopper plate 7 is a thick steel plate having a strength and rigidity that bears a horizontal force in the event of an earthquake, and is firmly attached to the column 1 by an insert anchor or the like attached later.
[0014]
Thereafter, the suspension structure is loosened to transmit the axial force borne by the pillar 1 to the seismic isolation device 6. After that, the suspended structure that has become useless is removed and diverted to seismic isolation for other pillars.
Thereafter, the same procedure is repeated for all the columns of the seismic isolation layer in the existing building to install the seismic isolation device 6. Thereafter, the stopper plate 7 is removed, and the seismic isolation work is completed as shown in FIG.
[0015]
[Effects of the present invention]
The seismic isolation method for an existing building according to the invention described in claim 1 has the following effects.
1 No additional concrete is required, the outer diameter of the column is kept the same as before the seismic isolation work, and the indoor space does not change (no restrictions).
2. The work of the seismic isolation method can be simplified and construction in a short construction period is possible.
3 Suspension structure, stopper plate, etc. that bear the axial force borne by the construction target pillar on other pillars can be diverted, and construction costs can be reduced.
4 The suspension structure that bears the axial force borne by the construction target column on other columns is installed above the upper part (upper floor) of the seismic isolation device installation area, so that a wide working space can be secured and welding work can be secured. There is little work using fire, and safety during construction can be secured.
5 There is little work that generates noise and vibration, and seismic isolation can be performed while living (using a building).
[Brief description of the drawings]
FIG. 1 is an elevational view at a stage where an axial force of a construction target column is transmitted to another column and the column is excised.
2 is a plan layout view of FIG. 1. FIG.
FIG. 3 is an elevational view at a stage where a seismic isolation device is installed on a pillar.
FIG. 4 is an elevational view showing a stopper plate attached state.
FIG. 5 is an elevation view of the completed seismic isolation work for the pillar.
[Explanation of symbols]
1 Pillar 2 Other pillar 4 PC steel wire (suspended structure)
5 Seismic isolation device mounting area 6 Seismic isolation device 7 Stopper plate

Claims (1)

In the method of repairing existing buildings to seismic isolation structures,
A stage where the axial force borne by the seismic isolation pillar of the existing building is transmitted to and supported by other pillars by the suspension structure;
Excising the seismic isolation device mounting position of the column;
Installing a seismic isolation device at the excision site;
A step of attaching a stopper plate that bears and bears the horizontal force at the time of an earthquake to the pillar in an arrangement straddling the excision site of the pillar vertically,
Thereafter, loosening the suspension structure and transmitting the axial force borne by the pillar to the seismic isolation device;
Hereinafter, in the same manner, installing the seismic isolation device to all the columns of the seismic isolation layer, and then removing the stopper plate,
A seismic isolation method for existing buildings.

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