JP3772248B2 - Seismic isolation method for intermediate floors of existing buildings - Google Patents

Description

[0001]
[Technical field to which the invention belongs]
This invention belongs to the field of technology for seismic isolation structure by installing seismic isolation devices on the intermediate floor of the building to improve the seismic safety of the existing building. Is a method of seismic isolation while using existing pillars on the intermediate floor.
[0002]
[Prior art]
As a prior art of a technique for installing a seismic isolation device on an intermediate floor of a building to make a seismic isolation structure, an existing building seismic isolation structuring method described in JP-A-8-338155 is recognized. However, this prior art installs a seismic isolation device using the existing pillars on the intermediate floor of the building, but installs a frame that includes a support jack under the beam of the superstructure of the building, and this frame supports the beam. After supporting the entire upper structure, cut the existing column, lift the entire upper structure with a support jack, install a seismic isolation device between the separated columns, and then switch the load on the gantry to the seismic isolation device The process is the main content. The construction method is based on the premise that the beam of the existing building is strong enough to support the superstructure by the frame.
[0003]
In addition, the applicant of the present application has proposed an invention of a method for seismic isolation structure using an existing pillar on the intermediate floor of an existing building in the specification and drawings of Japanese Patent Application No. 9-107683. However, this invention of the prior application mainly includes the addition of pre-stressed PC steel wire to increase the concrete by replacing the axial force of the existing column.
[0004]
[Problems to be solved by the present invention]
When implementing the method of seismic isolation while using an existing building, ensuring safety during construction is an absolute requirement, and the construction floor should be limited to a seismic isolation floor is required. In addition, it is important for effective use of the floor area after construction to minimize the increase in the cross section of the column due to seismic isolation.
[0005]
From such a point of view, the seismic isolation structuring method for an existing building described in the above-mentioned Japanese Patent Application Laid-Open No. 8-338155 is that after the pillar is cut, the entire upper structure of the building is lifted with a pedestal jack. The description is recognized in conjunction with FIG. Even in that state, if you think that an earthquake will occur, it will be recognized that this is very difficult to implement as a method of "isolating while staying" while using existing buildings. Further, in claims 2 to 4 of the same publication, it is recognized that a beam is installed between the tops of the columns of the lower structure or that the beams are installed between the legs of the columns of the upper structure. Effective use of the earthquake is difficult. Not only that, those skilled in the art understand that existing buildings often lack the strength of beams on the upper and lower floors supported by the gantry, and the reinforcement and support of the beams must be installed on multiple floors, etc. The problem is recognized.
[0006]
In addition, the method of seismic isolation structure using the existing pillar on the intermediate floor of the existing building described in the specification and the drawings of the above-mentioned Japanese Patent Application No. 9-107683 is the replacement of the axial force of the existing pillar. Because of the increase in the concrete with pre-stressed PC steel wire, the increase in column cross-section due to seismic isolation is significant, and there is a disadvantage in effective use of the floor area after construction. .
[0007]
Therefore, the purpose of the present invention is to limit the construction floor to a seismic isolation floor, to suppress the increase in the column cross section as much as possible, and to control the axial deformation of the column and ensure the soundness of the superstructure, In addition, it is intended to provide an intermediate floor seismic isolation structuring method that ensures seismic safety during construction and realizes construction of “isolation while staying” while using the building.
[0008]
[Means for Solving the Problems]
As means for solving the above problems, the intermediate floor seismic isolation structuring method for the existing building according to the invention of claim 1 is:
There intermediate floor rows roughening treatment skeleton surface of an existing column 1 of an existing building, the top and bottom of the outer periphery except for the isolator mounting portion L of the existing column 1, like an anchor a bisected halved steel tube joined by welding to complete the steel tube 4 and 5, the tool to integrate the existing Hashira 1 and steel pipe 4,5 by filling the mortar into the steel pipe, all existing Hashira 1 of the intermediate floors of an existing building The stage of attaching braces 8 and 9 at the time of construction between the steel pipes 4 and 5 of the existing pillar 1 determined by the number of brace points required for the earthquake under construction after that,
Only for the existing pillar 1 to which the seismic isolation device is attached, the braces 8 and 9 at the time of construction are temporarily removed, and the bracket 11 is removably attached to the outer surfaces of the upper and lower steel pipes 4 and 5 by bolting, support jack 10 placed between the upper and lower brackets 11, 11, replacing prime the axial forces to which the existing column 1 by introducing axial forces to drive the same support jack 10 is borne to the axial force of the support jack 10 Stages,
Cutting and removing the existing pillar 1 between the upper and lower steel pipes 4 , 5 ;
The seismic isolation device mounting plate 12 to the end surface of the upper and lower steel 4,5 tacked, attach the isolator 13 between the upper and lower seismic isolation device mounting plate 12, 12, each of the isolator mounting plate 12 and the steel tube Filling the gap between the end faces of 4 and 5 with mortar and the like;
After the filling mortar develops strength, the axial force of the support jack 10 is released and replaced with support by the seismic isolation device 13 , the support jack 10 is removed, and the braces 8 and 9 at the time of construction are replaced with the steel pipe 4 of the column. The stage of attaching to 5 ,
Hereinafter, the same step is repeated for all the existing pillars 1 .
[0011]
According to a second aspect of the invention, the intermediate sponge Shin structured method of existing buildings as claimed in claim 1, as a method of installing a support jack 10 between the upper and lower steel 4,5, the upper and lower steel 4,5 A bracket having an annular horizontal rib 17 on the outer periphery thereof is removably attached by bolting, and a support jack 10 is installed between the upper and lower horizontal ribs 17 .
According to a third aspect of the invention, in the intermediate sponge Shin structured method of existing buildings as claimed in claim 1, driving movement of the support jack 10, the axial force of the support jack 10 when introducing the axial force and displacement the size measure done by management, upon release of the axial force, and carrying out rapid variations by measuring the axial deformation of the isolator 13 is managed so as not to generate.
[0012]
Invention 請 Motomeko 4 wherein, in the intermediate sponge Shin structuring method of the existing building according to claim 1, for an existing column 1 which has completed installation of the seismic isolation device 13, the outer surface of the upper and lower steel 4,5 The stopper plate 16 for restraint is joined in between, and the stopper plate 16 is removed at the same time when the installation of the seismic isolation device 13 is completed on all the existing columns 1 of the existing building.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
The intermediate-floor seismic isolation structuring method for an existing building according to the invention described in claim 1 is carried out in the form shown in the key process diagrams in FIG.
First, as shown in FIG. 1, a roughening process (scattered portion) is performed on the surface of the frame of the existing pillar 1 on the intermediate floor (base isolation floor) of the existing building. The surface finish of the existing pillar 1 is removed, and the concrete surface is roughened with a chisel, etc., but the part to be cut later and the seismic isolation device is attached (length L range, L is about 450 mm) Leave it because the processing is wasted. In FIG. 1, reference numeral 2 ₃ denotes a third floor slab of an existing building selected as a seismic isolation floor, 2 ₄ denotes a fourth floor slab, and 3 denotes a beam on the fourth floor.
[0014]
FIG. 2 shows steel pillars 4 and 5 installed on the outer circumferences of the upper and lower parts excluding the mounting portion L of the existing seismic isolation device 1 and the existing pillars 1 and 5 are filled with a fixing material such as mortar. And the steps of integrating the steel pipes 4 and 5. As for the steel pipes 4 and 5, the outer diameter of the existing pillar 1 is 900 × 900 mm as shown in FIG. 5, whereas a half steel pipe obtained by dividing a square steel pipe of 1200 × 1200 mm and thickness 16 mm into two equal parts is existing. It is built in a similar arrangement from the left and right sides of the pillar 1 to the outer periphery, and a backing is provided on the abutting parting line and joined by welding to complete one steel pipe. The gap between the existing pillar 1 and each steel pipe 4, 5 is filled with mortar 6 and integrated. The lower end surface of the upper steel pipe 4 is closed with a bottom plate (not shown) so that the mortar 6 does not leak out. However, in order to achieve good integration of the seismic isolation device mounting plate, which will be described later, the bottom plate is made of a material that can be dismantled and removed later, such as plywood, and upwards for integration by the dowel effect. A slightly raised bottom is provided. Further, in order to achieve stronger integration with the existing pillar 1 by using the filling and hardening of the mortar 6, longitudinal and lateral inner studs 7 are provided inside the steel pipes 4 and 5 in the existing pillar 1. (Invention of claim 3). Incidentally, reference numeral 1 a in FIG. 5 indicates the steel frame of the existing pillar 1.
[0015]
FIG. 3 shows an embodiment of the second aspect of the invention. As described above, the construction of steel pipes 4 and 5 on the existing pillars of the intermediate floor (base isolation floor) of the building and the integration with the existing pillars 1 are for all the existing pillars of the intermediate floor of the existing building. Do. Thereafter, it is shown that the braces 8 and 9 at the time of construction are attached between the upper and lower steel pipes 4 and 5 of the existing pillar 1 by a bolt joining method that can be easily disassembled and removed later. This is to ensure seismic safety during the construction period of seismic isolation structuring of existing buildings and to realize “isolation while staying”. The brace 8 has a structure in which a stiffening pipe is fitted around the outer periphery of the H-shaped steel, and the brace 9 is formed of an H-shaped steel of about 200 × 200 × 8 × 12 mm. However, the braces 8 and 9 at the time of construction are attached to the existing pillars determined according to the number of required braces for the occurrence of an earthquake predicted during construction, instead of attaching the braces to all existing pillars. And only about the existing pillar which is the object of the installation construction of the seismic isolation apparatus performed as a later process, the braces 8 and 9 at the time of construction are temporarily removed to perform seismic isolation construction. Because the work of braces originally bears the horizontal force input to existing buildings due to earthquakes, etc., and eventually increases the axial force of the columns, so that such an effect does not occur on the columns during the seismic isolation construction Based on consideration to prevent. Therefore, as a matter of course, the braces 8 and 9 at the time of construction are attached to the steel pipes 4 and 5 of the column 1 again at the stage where the construction for seismic isolation is completed. In addition, each process of seismic isolation of the existing pillar 1 described below proceeds with the construction of several neighboring pillars as a unit of one group.
[0016]
Next, in FIG. 4, a support jack (hydraulic jack) 10 is installed between the upper and lower steel pipes 4 and 5, and the axial force is introduced by driving the support jack 10. The step of changing the force to the axial force of the support jack 10 is shown. 3 to 9, as a method of installing the support jack 10 between the upper and lower steel pipes 4, 5, the bracket 11 can be removed by bolting in an arrangement where the support jacks 10 are vertically opposed to the outer surfaces of the upper and lower steel pipes 4, 5. The structure (invention of Claim 4) which attached and installed the support jack 10 between the upper and lower brackets 11 and 11 is shown. As means for bolting the bracket 11 so that it can be removed later, the upper and lower steel pipes 4 and 5 are preliminarily provided with screw holes at the mounting position of the bracket 11 and are joined by one-side bolts screwed into the screw holes. 4 and 5 show a configuration in which a total of four brackets 11 and two support jacks 10 are used on the left and right sides of the steel pipe. The support jack 10 is driven by a management system in which the axial force and displacement of the support jack 10 are measured by a sensor when the axial force is introduced, and the analysis is consistently performed.
[0017]
Next, FIG. 6 shows a stage in which the existing column 1 between the upper and lower steel pipes 4 and 5 is cut and removed by a length L range. The existing pillar 1 is cut by, for example, diamond chain saw. The axial force (vertical load) applied to the existing column 1 is transmitted via the support jack 10.
FIG. 7 shows a stage in which the seismic isolation device mounting plate 12 is temporarily attached to the end surfaces of the upper and lower steel pipes 4 and 5. With respect to the upper steel pipe 4, the above-described bottom plate for mortar filling is removed and the lower surface of the hardened mortar is exposed, and then the seismic isolation device mounting plate 12 is temporarily attached. The seismic isolation device mounting plate 12 is a rigid plate that can withstand the load of axial force and bending moment caused by the seismic isolation device, and a sufficiently thick flat steel plate is used. The seismic isolation device mounting plate 12 is provided with a necessary number of bolt holes for mounting the seismic isolation device in advance, and has a configuration in which studs are provided so as to be firmly integrated with the upper and lower steel pipes 4 and 5 and the filling mortar. Has been. The temporary attachment of the seismic isolation device mounting plate 12 means a fixed state that does not hinder the seismic isolation device mounting operation.
[0018]
FIG. 8 shows that the seismic isolation device 13 is attached with bolts 14 between the upper and lower seismic isolation device mounting plates 12, 12, and the end surfaces of the filling mortar exposed in each of the seismic isolation device mounting plates 12 and the steel pipes 4, 5. The gap is completely filled with mortar or the like as a filler or a fixing material. If the mortar is completely cured, complete integration can be achieved by the bearing effect of the stud attached to the seismic isolation device mounting plate 12. The upper and lower seismic isolation device mounting plates 12 and the seismic isolation device 13 are joined by screwing a plurality of bolts 14 (see FIG. 9) into the bolt holes of the seismic isolation device mounting plate 12 from the seismic isolation device plate 13a side. Bolt connection. This is to facilitate future replacement or adjustment work. The seismic isolation device 13 is configured by sticking steel plates and rubber sheets alternately to form a columnar shape, and the outer diameter of the columnar portion is about 800 mm. Reference numeral 15 in FIG. 9 denotes a lead bar or low yield point steel that penetrates in the axial direction of the central portion of the seismic isolation device 13 as an energy absorbing damper.
[0019]
FIG. 10 shows that after the installation of the seismic isolation device 13 has been completed through the above-described steps and the filling mortar has sufficiently developed strength, the axial force of the support jack 10 is released and replaced with support by the seismic isolation device 13. The stage which removed the support jack 10 and the bracket 11 is shown. Therefore, the maximum diameter of the column 1 is only the outer diameter (1200 × 1200 mm) of the steel pipes 4 and 5. When the axial force of the support jack 10 is released, the axial deformation of the seismic isolation device 13 is measured and managed so as not to generate a sudden deformation (invention of claim 6). The removed support jack 10 and the bracket 11 will be diverted to the seismic isolation work for the next existing pillar.
[0020]
Hereinafter, the same construction stage is repeated for all existing pillars 1 on the intermediate floor (base isolation floor) in the existing building. However, for the existing column 1 for which the seismic isolation device 13 has been installed, a rigid stopper plate (steel plate) 16 for restraint is removed later between the outer surfaces of the upper and lower steel pipes 4 and 5, as shown in FIG. It is attached by the method of bolt joining that is easy. This is because horizontal forces such as earthquakes are input when a column with a seismic isolation device on an intermediate floor (base isolation floor) of an existing building and a column that has not yet been mounted (not cut) are mixed. Then, it is dangerous because the building is twisted. Therefore, at the stage where the installation of the seismic isolation device 13 is completed on all the existing pillars 1 of the existing building, all the stopper plates 16 are removed at the same time.
[0021]
Next, FIG. 12 and FIG. 13 are practical examples of the construction method for seismically isolating the intermediate floor of an existing building through basically the same steps as the invention of claim 1, and in particular, the above-described implementation. An example in which the means for installing the support jack 10 between the upper and lower steel pipes 4 and 5 is different in the case of a large-scale building where the axial force borne by the existing pillar is larger than the example will be shown. That is, brackets made up of annular horizontal ribs 17 and vertical ribs 18 are removably attached to the outer peripheries of the upper and lower steel pipes 4 and 5 (see FIG. 12). The horizontal ribs 17 are configured to be stiffened by arranging vertical ribs 18 on the upper surface side of the upper steel pipe 4 and on the lower surface side of the lower steel pipe 5 to function as a bracket. The support jack 10 is installed between the upper and lower horizontal ribs 17 and 17. According to the configuration of the present embodiment, the bending moment generated when the axial force of the column is replaced with the axial force of the support jack 10 is offset by the tensile stress of the horizontal rib 17 and is applied to the joint bolt with the steel pipes 4 and 5. Only shear force is transmitted, which is mechanically advantageous.
[0022]
[Effects of the present invention]
According to the seismic isolation structure method for existing floors of an existing building according to the present invention, the construction floor is limited to the middle floor (base isolation floor) of the building, and the axial force borne by the existing pillar is integrated from the same pillar to its outer periphery. As a result of removing the support jack, the increase in the column cross-section is suppressed to the limit of the outer diameter of the steel pipe as much as possible, and effective use of the floor area after construction It is great when it contributes to
[0023]
Also, support jacks and braces during construction are used in combination to control the axial deformation of the columns, ensuring the soundness of the superstructure and ensuring seismic safety during construction. Construction of seismic isolation can be realized. In addition, since the existing pillars are supported in principle, there is no troublesome burden such as reinforcing a specific part of the existing building or using the support together.
[0024]
The installation of each temporary bracket, brace, stopper plate, etc. is bolted and no fire is used, so construction safety is guaranteed and each temporary object can be diverted, which is economical.
[Brief description of the drawings]
FIG. 1 is an elevational view showing a roughening stage of an intermediate floor seismic isolation structuring method according to the present invention.
FIG. 2 is an elevation view showing a stage of integration of a steel pipe with an existing column.
FIG. 3 is a partial view showing the installation situation of braces during construction.
FIG. 4 is an elevational view showing an installed state of the support jack.
5 is a view taken along line AA in FIG.
FIG. 6 is an elevation view showing a cutting situation of a pillar.
FIG. 7 is an elevation view showing a temporary attachment state of the seismic isolation device mounting plate.
FIG. 8 is an elevational view showing the installation state of the seismic isolation device.
FIG. 9 is a view taken along the line BB in FIG.
FIG. 10 is an elevation view showing a state where the installation of the seismic isolation device is completed.
FIG. 11 is an elevation view showing a state in which a stopper plate is attached to the seismic isolation device.
FIG. 12 is an elevational view showing different examples of the installation situation of the seismic isolation device.
13 is a view taken along the line CC of FIG.
[Explanation of symbols]
1 Existing Column L Seismic Isolator Installation Site 4, 5 Steel Pipe 6 Mortar 10 Support Jack 12 Seismic Isolator Installation Plate 13 Seismic Isolator 8, 9 Brace 11 During Construction Bracket 17 Horizontal Rib 16 Stopper Plate

Claims (4)

There rows roughening treatment skeleton surface of the intermediate floor of an existing column of an existing building, the top and bottom of the outer periphery except for the isolator mounting portion of the existing columns, welded like an anchor a bisected halved steel tube and to complete the steel pipe, the work to integrate the existing pillars and steel pipe is filled with a mortar or the like in the same steel pipe, performed for all of the intermediate floor of the existing pillars of the existing building, to the earthquake in Thereafter construction Attach the braces during construction between the steel pipes of the existing columns determined by the number of required brace points by bolting ;
Remove the braces during construction only for the existing columns to which the seismic isolation device is attached, and install the brackets so that they can be removed by bolting in a manner that they face the outer surfaces of the upper and lower steel pipes, and support jacks between the upper and lower brackets. Installing the shaft, introducing the axial force by driving the support jack, replacing the axial force borne by the existing pillar with the axial force of the support jack,
Cutting and removing existing pillars between the upper and lower steel pipes;
Temporarily attach seismic isolation device mounting plates to the upper and lower steel pipe end faces, install seismic isolation equipment between the upper and lower seismic isolation equipment mounting plates, and put mortar etc. in the gap between each seismic isolation equipment mounting plate and the end face of the steel pipe. Filling, and
After the filling mortar develops strength, the axial force of the support jack is released and replaced with support by a seismic isolation device, the support jack is removed and the brace is attached to the steel pipe of the column again during construction ,
In the following, the intermediate floor seismic isolation structuring method for existing buildings, characterized by repeating the same steps for all existing columns. As a method of installing a support jack between the upper and lower steel pipes, a bracket having an annular horizontal rib on the outer circumference of the upper and lower steel pipes is removably attached by bolting, and a support jack is installed between the upper and lower horizontal ribs. The intermediate floor seismic isolation structuring method for an existing building according to claim 1, characterized in that it is characterized in that Driving movement of the support jack, in introducing axial forces is carried out by measuring the axial force and the magnitude of the displacement of the support jack manage and upon release of the axial force measuring axial deformation of the isolator The intermediate floor seismic isolation method for an existing building according to claim 1, wherein the method is performed so as not to cause sudden deformation. For existing columns that have completed installation of seismic isolation devices, a stopper plate for restraint is joined between the outer surfaces of the upper and lower steel pipes, and at the same time the installation of seismic isolation devices is completed on all existing columns of the existing building. The intermediate floor seismic isolation structuring method for an existing building according to claim 1, wherein the stopper plate is removed.

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