JP3760306B2 - Seismic isolation method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a seismic isolation method for isolating existing buildings.
[0002]
[Prior art]
In order to improve the seismic performance of existing buildings, there is a seismic isolation method in which seismic isolation devices such as laminated rubber are installed on the foundations or intermediate floors of existing buildings, and the upper part is seismically isolated by this installed seismic isolation device. Has been done.
[0003]
By the way, as one of the above seismic isolation methods, the entire part of the existing building that is going to be seismic isolated temporarily is temporarily installed with temporary materials, and after the seismic isolation device is installed, the jack is used to isolate the temporary building from the temporary materials. A method of transferring the building weight to the device is considered.
[0004]
[Problems to be solved by the invention]
However, in the above-mentioned seismic isolation method, the entire part of the existing building to be seismically isolated is temporarily supported by temporary materials. There is a problem that a lot of temporary materials need to be arranged in the immediate vicinity, and the number of temporary materials to be used increases.
[0005]
In particular, in the case of seismic isolation of the intermediate floor and above, as shown in FIGS. 10 and 11 , for example, in order to support the beam 102 connected to the column 101 on which the seismic isolation device 100 is installed, In some cases, a relatively long support 103 may be required, and the number of supports 103 at that time increases, and a work for installing the support including a fixing member for fixing the support 103 is required. There was a possibility that a new problem of large scale would arise. In addition, there is a possibility that the scaffold 104 must be installed on the entire floor.
[0006]
In addition, as a countermeasure against earthquakes at the time of temporary reception, it is necessary to install temporary materials that can resist the horizontal force obtained by multiplying the total weight of the existing building by a certain value (for example, 15 percent). In many cases, these temporary materials are installed together in several places around the building, and there is also a problem that the temporary materials for horizontal force resistance per location become large.
[0007]
The present invention has been made in view of the above circumstances, and the object of the present invention is to reduce the number of temporary materials to be used, and even in the case of seismic isolation of intermediate floors or more, it is a large and large amount. The purpose of this is to provide a seismic isolation method that does not require large-scale support and does not require a large-scale scaffolding.
Another object of the present invention is to provide a seismic isolation method that can eliminate the need for large temporary materials for horizontal force resistance as a measure against earthquakes during the installation process of the seismic isolation device.
[0008]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, the invention according to claim 1 is a seismic isolation method for seismic isolation by installing a seismic isolation device in an existing building, and a predetermined number of columns among a plurality of pillars of the existing building. For each pillar, the weight of the existing building borne by the pillar is received by a temporary material, the pillar is cut and a seismic isolation device is installed at the cut location, and the existing pillar is borne by the installed seismic isolation device By repeating the work of transferring the weight of the building from the temporary material and removing the temporary material, seismic isolation devices are sequentially installed on all of the plurality of pillars and the temporary material is sequentially removed. In addition, during the process of installing seismic isolation devices sequentially for all of these pillars and removing temporary materials, the weight of the existing building will be transferred from the temporary materials to each seismic isolation device. prior to each individual horizontal displacement around each isolator By sequentially installed bundle means, by the individual by horizontal displacement restraining means, it is characterized in that to restrain the horizontal displacement of the upper portion than places to install a seismic isolation device of an existing building.
According to a second aspect of the present invention, there is provided the mounting plate according to the first aspect of the invention, wherein the individual horizontal displacement restraining means is fixed above and below the column cutting portion and is respectively installed above and below each seismic isolation device. The individual horizontal displacement restraining unit restrains the relative horizontal displacement of the parts, and the individual horizontal displacement restraining unit includes a pair of pedestals engaged across the upper and lower mounting plate parts, and the pedestals with a predetermined load. A plurality of sets of individual horizontal displacement restraining units are arranged around each seismic isolation device so that the axes are oriented in two directions orthogonal to each other. It is characterized by doing.
[0009]
According to the present invention, for each predetermined number of pillars in an existing building, while the vertical load of the existing building is supported by temporary materials, the pillar is cut and the seismic isolation device is installed, and the load is transferred to the installed seismic isolation device. In addition, by repeating the work of quickly removing the temporary material, all the seismic isolation devices are installed, and at the same time, the transfer of the weight of the existing building is completed.
Moreover, since the temporary materials for vertical loads that have been sequentially removed can be used repeatedly, the amount used is greatly reduced as compared with the conventional construction method.
[0010]
In addition, as described above, the weight of the existing building can be transferred simultaneously with the installation of all the seismic isolation devices by transferring the load to the seismic isolation devices installed and removing the temporary materials promptly. Since it is completed, the process of transferring the entire weight of the entire building from the temporary material to the seismic isolation device using the jack after the seismic isolation has been eliminated, and the construction period is shortened accordingly.
In addition, considering the balance of the entire building, it is possible to proceed with the installation of seismic isolation devices simultaneously from multiple locations such as two sides on the left and right sides of the existing building or four sides on the front and rear sides. It can be shortened.
[0011]
Moreover, since individual horizontal displacement restraining means are sequentially installed around each seismic isolation device, there is no need to install a large temporary material for horizontal force resistance at the time of the earthquake. Save space. As the individual horizontal displacement restraint means, an individual horizontal restraint unit configured to restrain the relative horizontal displacement of the upper and lower mounting plate parts of the seismic isolation device by tensioning a pair of pedestals with a tension bar is adopted. It is preferable to install each of the seismic isolation devices so that they are oriented in two horizontal directions.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the seismic isolation method of the present invention will be described with reference to the drawings.
1 to 9 show an embodiment of the present invention. FIG. 1 is a cross-sectional view showing a part of an existing building where a seismic isolation device is installed, and FIGS. 2 to 5 are specific examples of the seismic isolation device. FIG. 6 is a side view for explaining the individual horizontal displacement restraining means for restraining the relative horizontal displacement of the upper and lower mounting plate portions of the seismic isolation device, and FIG. FIG. 8 is a side view showing another example of the individual horizontal restraint means, and FIG. 9 is a side view showing still another example of the individual horizontal displacement restraint means .
[0013]
In FIG. 1, reference numeral 1 denotes an existing building, and seismic isolation devices 3 such as laminated rubber are respectively installed on a plurality of pillars 2 of the existing building 1 (see FIGS. 4 and 5). The pillar installed by the seismic isolation device 3 may be either the base portion of the existing building 1 or an intermediate floor.
The most significant feature of the seismic isolation method of the present invention is that the seismic isolation device 3 is installed with the column load received by the temporary material 4 and the load applied to the column 2 being zero, and then the load is transferred from the temporary material 4 to the seismic isolation device. The task of transferring and removing the temporary material 4 is to be repeated for each of a predetermined number of pillars 2 among the plurality of pillars 2 of the existing building 1.
[0014]
That is, in the seismic isolation method of the present invention, for each predetermined number of pillars 2 out of a plurality of pillars 2 of the existing building 1, only the weight of the existing building 1 borne by the pillar 2 is received by the temporary material 4, The base 2 is cut and a seismic isolation device 3 is installed at the cut location, and then the weight of the existing building 1 borne by the pillar 2 is transferred from the temporary material 4 to the seismic isolation device 3 installed thereafter. The greatest feature is that the seismic isolation device 3 is installed on all of the plurality of pillars 2 while the work of removing the material 4 is repeated.
[0015]
In the case of this embodiment, the method of installing the seismic isolation device 3 in the existing building 1 is to install the seismic isolation device 3 in a well-balanced manner from both the left and right sides of the existing building 1 in consideration of earthquakes that occur during construction. . FIG. 1 shows only approximately the left half of the entire existing building 1, but the building actually extends in the right direction shown in FIG. In this figure, symbols A-1, B-1 (not shown),..., An, Bn,... (N is an integer of 16 or less) indicate the numbers of the pillars 2, respectively. The seismic isolation device 3 is installed for each of the two pillars 2 from the left and right sides of the building in the order of the numbers of the pillars 2.
The number of pillars for installing the seismic isolation device 3 at the same time is not limited to two, and may be every one, every three, or every four. It is determined by the number of pillars 2 that are present.
[0016]
The specific installation method of the seismic isolation device 3 on the pillar 2 will be described. For example, in order to install the seismic isolation device 3 on the pillar 2 (A-7), first, the pillar 2 (A-7) is connected. A jack 4a is attached as a temporary member 4 between the front and rear left and right large beams 6 and the lower beam 7 below (see FIGS. 1 and 2). And the weight of the existing building 1 which the pillar 2 (A-7) bears to the attached jack 4a is received. The number of the jacks 4a is four in this figure, but is not limited to this, and may be three or two, for example, when the load that the jack 4a bears is small.
[0017]
Next, a part of the pillar 2 where the seismic isolation device 3 is to be installed is cut out (see FIG. 3). A base plate 10 (attachment plate portion) is attached to the lower end portion 8 and the upper end portion 9 that are the cut ends of the column 2 (A-7) by appropriate fixing means such as welding. The base plate 10 may be directly attached to the end of the column, but may be fixedly attached to the large beam 6 or the small beam 7 via the anchor 6a as shown in FIG. Then, the seismic isolation device 3 is installed and fixed between the upper and lower base plates 10.
[0018]
Next, a grout material such as non-shrink mortar is injected into the gap between the end of the column 2 (A-7) and the base plate 10. The weight of the existing building 1 that the pillar 2 (A-7) bears from the jack 4a to the seismic isolation device 3 when the injected grout material solidifies and exhibits sufficient strength. Change minutes. Thereafter, the jack 4a is removed.
A series of operations such as the above jack setting → column cutting → base plate mounting → seismic isolation device installation → grouting material injection → jack removal is repeated for each predetermined number of columns 2 while moving the jack 4a which is the temporary material 4. The seismic isolation device 3 is installed for all the pillars 2 of the existing building 1.
[0019]
In addition, it takes a plurality of days (for example, about 4 days) from the jack set to the jack removal, and during that time, the pillar 2 is in a state of being cut, and in the support by the jack 4a, the pillar 2 is mainly used. It only receives the applied vertical load. For this reason, the pillar 2 under construction has almost no resistance in the horizontal direction. Therefore, in consideration of safety against horizontal load during construction, the number of columns 2 that are simultaneously cut shall be kept below a predetermined number (for example, four).
[0020]
In this embodiment, the installation work of the seismic isolation device 3 is advanced for each of the two pillars 2 in total, one from each of the left and right sides of the existing building 1, but the cutting state of the pillars 2 advanced from one side overlaps. The number of laps is limited to two. In other words, taking the pillar 2 on the left side of the building as an example, when the construction start time of the seismic isolation device 3 is shifted by two days, as described above, the period from the jack set to the jack removal is Since it takes about 4 days, two pillars 2 are cut simultaneously, such as pillar 2 (A-1) and pillar 2 (A-2), or pillar 2 (A-2) and pillar 2 (A-3). However, in the case where the installation work start time of the seismic isolation device 3 is shifted only one day, for example, pillar 2 (A-1), pillar 2 (A-2) and pillar 2 (A Since a total of four columns of −3) and column 2 (A-4) are simultaneously cut, it is not preferable. In order to avoid such a situation, it is assumed that the number of pillars 2 that are simultaneously cut is kept below a predetermined number (for example, four).
[0021]
By the way, as described above, the seismic isolation devices 3 are sequentially installed on the plurality of pillars 2. When a certain number of installations are completed, for example, when an earthquake occurs, horizontal force concentrates on the pillars 2 that have not yet been constructed. As a result, the unconstructed pillar 2 may be damaged.
For this reason, until the installation to all the pillars 2 of the seismic isolation device 3 is completed, the horizontal displacement restraining means 12 restrains the horizontal displacement of the portion above the location where the seismic isolation device 3 of the existing building 1 is installed. .
[0022]
As the horizontal displacement restraining means 12, individual horizontal displacement restraining means 12A for restraining the relative horizontal displacement of the upper and lower base plates 10 sandwiching the seismic isolation part 3a of the seismic isolation device 3 with respect to each seismic isolation device 3 (FIG. 5-7, 8 and 9) .
[0023]
5 to 7 show examples of the individual horizontal displacement restraining means 12A. In other words, in this example, a pair of pedestals 14 that engage with the base plate 10 is provided between the upper base plate 10 and the lower base plate 10 so as to be spaced apart from each other, and the pedestals 14 that form the pair are made of PC steel or the like. The tension bar 15 is pulled so as to approach each other with a predetermined load.
Further, in this example, the individual horizontal displacement restraining unit 16 composed of the pair of bases 14 and the tension bar 15 is oriented in the X and Y directions perpendicular to each other along the horizontal plane, and two sets in total. Four sets are arranged on the pillar 2 (see FIG. 7).
[0024]
According to the individual horizontal displacement restraining means 12A, the pair of pedestals 14 are pulled together by the tension bar 15, so that the pair of pedestals 14 strongly press the lower base plate 10 from both sides. While being fixed to the lower base plate 10 by being sandwiched, the pedestal 14 strongly sandwiches the upper base plate 10 from both sides, so that the displacement of the upper base plate 10 along the longitudinal direction of the tension bar 15 is reduced. Restrained. As a result, the individual horizontal restraint unit 16 can restrain the relative horizontal displacement along the longitudinal direction of the tension bar 15 of the upper and lower base plates 10. Further, the individual horizontal restraint units 16 are arranged in the X and Y directions orthogonal to each other along the horizontal plane. Therefore, the upper and lower base plates 10 are restrained from relative horizontal displacement in any direction. .
[0025]
The individual horizontal displacement restraining means 12 </ b> A is not necessarily limited to that shown in FIGS. 5 to 7, and other structures may be used. In short, the seismic isolation device 3 is different from the individual seismic isolation device 3. Any structure that restrains the relative horizontal displacement of the base plates 10 disposed above and below may be used.
For example, what is shown in FIG. 8 is that H-shaped steels 18 are vertically attached between the large beam 6 and the small beam 7 connected to the column 2 on which the seismic isolation device 3 is installed. The steel plate 19 is fixedly attached to the structure.
Further, the structure shown in FIG. 9 has a structure in which a grooved steel 20 is attached between the large beam 6 and the small beam 7 and a plurality of steel plates 21 are fixedly attached to the upper and lower grooved steels 20. Yes.
In such a structure, the members constituting the individual horizontal displacement restraining means 12A restrain the horizontal displacement of the upper and lower base plates via the large beam 6 and the small beam 7 without directly contacting the base plate 10. What is necessary is just to restrain the relative horizontal displacement of the baseplate 10 distribute | arranged to the upper and lower sides of the seismic isolation apparatus 3 in short.
[0026]
When the individual horizontal displacement restraining means 12A as described above is assembled to the seismic isolation device 3, the seismic isolation device 3 is attached to the column 2 and injected into the gap between the end of the column 2 and the base plate 10. This is after the grout material has hardened and before the weight of the existing building 1 is transferred from the jack 4a to the seismic isolation device 3.
[0029]
The installation procedure A-1, B-1 → A-2, B-2 → A-3, B-3 → …… of the seismic isolation device 3 described above was subjected to sufficient stress analysis in advance. It is preferable to set a system for monitoring the behavior of the existing building 1 for 24 hours by installing a monitoring camera or the like at a required location during the construction.
[0030]
Next, the operation of the seismic isolation method having the above configuration will be described.
According to the above-mentioned seismic isolation method, for each predetermined number of pillars 2 of the existing building 1, the weight of the existing building 1 borne by the pillar 2 is supported by the temporary material 4 such as the jack 4a, and the seismic isolation is performed in this state. This is a method of installing the seismic isolation device 3 for all the pillars 2 by repeatedly performing the work of installing the device 3 on the cut portion of the pillar 2 while moving the temporary material 4, and thus the vertical load. Since the temporary material 4 for use can be used repeatedly, the amount of the temporary material 4 used is greatly reduced as compared with a conventionally considered method.
[0031]
Moreover, since the transfer of the weight of the existing building 1 to the seismic isolation device 3 is completed at the same time that all the seismic isolation devices 3 are installed, temporary materials using jacks after the seismic isolation installation, which has been conventionally performed separately This eliminates the need to transfer the building weight from the seismic isolation device 3 to the seismic isolation device 3, thereby shortening the work period.
In addition, while considering the balance of the entire building, the installation work of the seismic isolation device 3 can proceed simultaneously from a plurality of locations, such as two sides on the left and right sides of the existing building 1 or four sides on the left and right sides. The construction period can be shortened.
[0032]
Even if an earthquake occurs in the middle of construction, the horizontal displacement restraining means 12 restrains the horizontal displacement of the portion above the place where the seismic isolation device 3 of the existing building 1 is installed. It is possible to avoid a situation where the horizontal force is concentrated on the non-worked pillar 2 and the unworked pillar 2 is damaged.
[0033]
Further, as the horizontal displacement restraining means 12, individual horizontal restraining means 12 A for restraining the relative horizontal displacement of the upper and lower base plates 10 with respect to the individual seismic isolation devices 3 , particularly a pair of bases 14 are engaged with the upper and lower base plates 10. By adopting the individual horizontal displacement restraint unit 16 configured to be tensioned by the tension bar 15 and installing it so as to surround the seismic isolation device so as to face the two horizontal directions around it, horizontal displacement during construction In addition to being able to effectively restrain the structure, it is no longer necessary to install large temporary materials or seismic isolation pits for horizontal force resistance in the vicinity of the building, saving space and reducing costs.
[0034]
In the above embodiment, the case where the rectangular existing building 1 is seismically isolated has been described as an example. However, of course, even an existing building having a square cross section or an existing building having a circular cross section is used. However, it goes without saying that seismic isolation is possible.
Also, the seismic isolation device used for seismic isolation is not limited to laminated rubber, and other types of seismic isolation devices may be used.
[0035]
【The invention's effect】
According to the invention of claim 1, for each predetermined number of pillars of the existing building, the weight of the existing building borne by the pillar is supported by temporary materials such as a jack, and in this state, the seismic isolation device is a part of the pillar cut This is a construction method that installs seismic isolation devices for all the pillars by moving the temporary materials while moving the temporary materials, and the temporary materials for vertical loads can be used repeatedly. The amount of use can be greatly reduced compared to a conventionally considered method.
[0036]
In addition, since the transfer of the existing building's weight to the seismic isolation device is completed at the same time as installing all the seismic isolation devices, the seismic isolation has been carried out from the temporary material using jacks after the seismic isolation has been performed separately. The process of transferring the building weight to the equipment becomes unnecessary, and the construction period is shortened accordingly.
Considering the balance of the entire building, for example, it is possible to proceed with the installation work of seismic isolation devices from multiple locations, such as two on the left and right sides of the existing building or four on the front, back, left and right. This also shortens the construction period. I can plan.
In addition, even if the base floor is seismically isolated, a large scale does not require a large amount of support, and the scaffold can be used while moving, so a very small scale is sufficient.
[0037]
Moreover, during the installation process of the seismic isolation devices, individual horizontal displacement restraining means are sequentially installed around each seismic isolation device, so that the horizontal displacement during construction can be effectively restrained, as well as around the building periphery. There is no need to install large temporary materials or seismic isolation pits for horizontal force resistance during an earthquake, saving space and significantly reducing costs.
[0038]
According to the second aspect of the present invention, the individual horizontal displacement restraining means is configured to restrain the relative horizontal displacement of the upper and lower mounting plate portions of the seismic isolation device by tensioning the pair of bases with the tension bar. By adopting a horizontal restraint unit and surrounding each seismic isolation device so that it is oriented in two horizontal directions around it, effective relative horizontal displacement in all directions of the upper and lower mounting plates is effective. Can be restrained.
[Brief description of the drawings]
FIG. 1 shows an embodiment of the seismic isolation method of the present invention, and is a cross-sectional view showing a part where an existing base isolation device is installed.
FIG. 2 shows an embodiment of the seismic isolation method of the present invention, and is a cross-sectional view illustrating a specific installation process of the seismic isolation device.
FIG. 3 shows an embodiment of the seismic isolation method of the present invention, and is a cross-sectional view illustrating a specific installation process of the seismic isolation device.
FIG. 4 shows an embodiment of the seismic isolation method of the present invention, and is a cross-sectional view for explaining a specific installation process of the seismic isolation device.
FIG. 5 shows an embodiment of the seismic isolation method of the present invention, and is a cross-sectional view illustrating a specific installation process of the seismic isolation device.
FIG. 6 is a side view illustrating an individual horizontal displacement restraining means according to the embodiment of the seismic isolation method of the present invention.
FIG. 7 shows an embodiment of the seismic isolation method of the present invention and is a plan view for explaining a specific installation process of the seismic isolation device.
FIG. 8 is a side view showing another embodiment of the individual horizontal restraint means according to the embodiment of the seismic isolation method of the present invention.
FIG. 9 is a side view showing still another example of the individual horizontal displacement restraining means according to the embodiment of the seismic isolation method of the present invention.
FIG. 10 is a side view of the entire building showing a conventional seismic isolation method.
FIG. 11 is an enlarged view of an X circle part of FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Existing building 2 Pillar 3 Seismic isolation device 4 Temporary material 4a Jack 6 Large beam 7 Small beam 10 Base plate (mounting plate part)
12 Horizontal displacement restraint means 12A Individual horizontal displacement restraint means
14 pedestal
15 Tension bar
16 Individual horizontal displacement restraint unit

Claims (2)

A seismic isolation method for seismic isolation by installing seismic isolation devices in existing buildings,
For each of a certain number of pillars in an existing building, the temporary building material receives the weight of the existing building borne by the pillar, cuts the pillar, and installs a seismic isolation device at the cut location. The seismic isolation device is applied to all the plurality of pillars by repeatedly transferring the weight of the existing building borne by the pillar to the installed seismic isolation device from the temporary material and removing the temporary material. We install sequentially and remove the temporary materials sequentially ,
Moreover, during the process of sequentially installing seismic isolation devices for all of these pillars and removing temporary materials in sequence , prior to transferring the weight of the existing building from the temporary materials to each seismic isolation device. , constrained by going respectively sequentially placed individually horizontal displacement restraining means around each isolator, the individual by horizontal displacement restraining means, the horizontal displacement of the upper portion than places to install a seismic isolation device of an existing building Seismic isolation method characterized by As the individual horizontal displacement restraining means, an individual horizontal displacement restraining unit that restrains the relative horizontal displacement of the mounting plate portions fixed respectively above and below the column cutting portions and installed above and below each seismic isolation device. While using
Individual by horizontal displacement restraining unit has a pair of pedestals engaging over the top and bottom of the mounting plate portion is constituted by a tension rod pulling them pedestal each other to be closer to each other at a predetermined load, the individual by horizontal displacement restraining unit The seismic isolation method according to claim 1 , wherein a plurality of sets are arranged around the seismic isolation devices in a state where their axes are oriented in two directions orthogonal to each other .

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