JP2013053407A - Seismic isolation method for existing building - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a seismic isolation method for an existing building with a mixture of seismic isolation devices having a different vertical rigidity, which allows each of the seismic isolation devices having a different vertical rigidity to be applied with a designed axial force, achieving predetermined seismic isolation performance.SOLUTION: A seismic isolation device A having a low vertical rigidity is joined to an upper structure 5 and a lower structure 6 of an existing building, while a seismic isolation device B having a high vertical rigidity is joined to the lower structure 6 and not joined to the upper structure 5. In this state, a temporary support column 4 corresponding to the seismic isolation device having a low vertical rigidity is unloaded, while the pressure of a jack 4b of a temporary support column 4 corresponding to the seismic isolation device having a high vertical rigidity which is not joined to the upper structure is adjusted so that the building load applied to the temporary support column is maintained at a fixed state. Subsequently, the seismic isolation device having a high vertical rigidity is joined to the upper structure, and the temporary support column corresponding to the device is then unloaded.

Description

The present invention provides a seismic isolation device having a different vertical rigidity (for example, a spring-supporting seismic isolation device and a sliding bearing-based seismic isolation device) as a seismic isolation device interposed between an upper structure and a lower structure of an existing building. This is related to the seismic isolation method for existing buildings.

The upper structure of the existing building is temporarily received by a temporary support post with a hydraulic jack, and in this state, the axial force transmission member (pile or column) between the upper structure and the lower structure is cut and removed, and the axial force transmission member is removed. The seismic isolation device is installed in each of the axial force transmission paths borne by the removed axial force transmission member, such as directly under the beam adjacent to the axial force transmission member. In the seismic isolation method for existing buildings, the building load is transferred from the seismic isolation device to the seismic isolation device.
For the purpose of building vibration control, as a seismic isolation device, a spring bearing type seismic isolation device typified by laminated rubber bearings and a sliding bearing type exemption using orthogonal slide rails (roller bearings) or surface friction materials. Seismic devices may be mixed. Further, even in the same spring support type seismic isolation device, it is already known from Patent Document 1 that a laminated rubber bearing having a high vertical rigidity and a laminated rubber bearing having a low vertical rigidity are distributed and arranged on the inside and outside of the building. Yes.

Paragraph 0006 of Patent Document 2 describes a spring-supporting seismic isolation device and a sliding-supporting seismic isolation device.
There is a big difference of about 5 to 10 times in vertical rigidity as described in
When the superstructure of an existing building is temporarily received with a temporary support post, the temporary support post is unloaded (jacked down) and the building load is transferred from the temporary support post to the seismic isolation device. If the load is transferred to both the seismic isolation device and the sliding support type seismic isolation device at the same time, the load may concentrate on the sliding support type seismic isolation device with high vertical rigidity.

That is, as shown in FIG. 6, a spring bearing type seismic isolation device A and a sliding bearing type seismic isolation device B are arranged at adjacent positions, and above and below the seismic isolation devices A and B and above the existing building. Substructure 5, 6
7, the unloading of the temporary support post 4 (jack down by the jack 4 b) is performed as shown in FIG. 7, and the adjacent spring support type seismic isolation device A and sliding support type seismic isolation device B are used. When the load is transferred at the same time, the amount of contraction due to loading is large in the spring isolation system A with low vertical rigidity, while the amount of contraction due to loading is small in the base isolation system B with high vertical rigidity. Therefore, due to the difference in the amount of shrinkage of the seismic isolation devices A and B due to this load introduction, the beam 9 and the slab 8
There is a high possibility that a load flows in the direction of the seismic isolation device B having high vertical rigidity. As a result, a load higher than the design is introduced into the seismic isolation device B having a high vertical rigidity, and it is possible that the predetermined seismic isolation performance cannot be exhibited as a whole, so that advanced construction management is necessary. .

JP 2009-121043 A JP 2001-288289 A

The present invention has been made in view of the above-mentioned problems, and the object is as follows.
In the seismic isolation method for existing buildings where seismic isolation devices with different vertical stiffnesses are mixed as seismic isolation devices that are interposed between the upper and lower structures of existing buildings, The building load can be introduced as designed, and the desired seismic isolation performance can be exhibited.

In order to achieve the above object, technical measures taken by the present invention are as follows. That is,
The invention according to claim 1 is a seismic isolation method for an existing building in which seismic isolation devices having different vertical stiffnesses are mixed as a seismic isolation device to be interposed between the upper structure and the lower structure of an existing building. Of the seismic isolation devices with high vertical rigidity and low vertical rigidity, the seismic isolation devices with low vertical rigidity are joined to the upper and lower structures of existing buildings. Unload the temporary support strut corresponding to the seismic isolation device with low vertical rigidity in a state where it is joined to the lower structure of the existing building and is not joined to the upper structure, and the vertical structure that is not joined to the upper structure of the existing building. For the seismic isolation device with high rigidity, by adjusting the pressure of the jack of the temporary support column, the building load applied to the temporary support column is kept constant, and then the seismic isolation device with high vertical rigidity is installed on the existing building. Vertical stiffness after joining with superstructure It is characterized by performing the unloading of the temporary supporting struts corresponding to high seismic isolation device. In the present invention, “holding the building load applied to the temporary support column” in a constant state means to keep it within an allowable range, and does not necessarily have to be constant in a strict sense.

The invention according to claim 2 temporarily receives the upper structure of the existing building with a temporary support post with a jack, and in this state, the axial force transmission member between the upper structure and the lower structure is cut and removed, and the removed shaft is removed. Existing seismic isolation renovation of existing buildings by installing seismic isolation devices in the axial force transmission path borne by the force transmission member and transferring building loads from temporary support posts to seismic isolation devices A seismic isolation method for buildings,
The building load when the axial force transmission member applied to the temporary support struts corresponding to each of the sliding support type seismic isolation device and the spring support type seismic isolation device arranged adjacent to each other is cut and removed is stored in the temporary support post. A first step of measuring with a pressure gauge attached to the jack;
Install the spring support type seismic isolation device on the existing building and joined with the lower structure, and install the sliding support type seismic isolation device on the existing building's lower structure and unconnected with the upper structure. The second step;
Unload the temporary support struts corresponding to the spring bearing type seismic isolation device, and for the sliding support type seismic isolation device that is not joined to the superstructure of the existing building, the jack pressure of the temporary support column A third step of keeping the building load applied to the temporary support column in a constant state by adjusting the measurement value in one step to be held;
A fourth step of unloading the temporary support column corresponding to the sliding support type seismic isolation device after joining the sliding support type seismic isolation device with the superstructure of the existing building is characterized.

Invention of Claim 3 is the seismic isolation method of the existing building of Claim 2, Comprising: An axial force transmission member is a pile head, It is characterized by the above-mentioned.

The invention described in claim 4 is the seismic isolation method for an existing building described in claim 2, characterized in that the axial force transmission member is a column.

According to invention of Claim 1, a building load can be introduce | transduced into a seismic isolation apparatus from which vertical rigidity differs, as designed, and predetermined seismic isolation performance can be exhibited. In other words, the seismic isolation device with high vertical rigidity is not yet joined to the superstructure of the existing building, and the temporary support column corresponding to the base isolation device with low vertical rigidity is unloaded. On the equipment side, the building load applied to the temporary support strut is kept constant or nearly constant by adjusting the jack pressure of the temporary support strut according to the amount of shrinkage caused by the loading of the seismic isolation device with low vertical rigidity. In this state you can
After the seismic isolation device with high vertical rigidity is joined to the superstructure of the existing building, the temporary support struts corresponding to the seismic isolation device with high vertical rigidity are unloaded. Will not be introduced.

According to the second aspect of the present invention, each of the sliding support type seismic isolation device having a high vertical rigidity and the spring support type having a low vertical rigidity arranged in adjacent positions is provided in the first step. A load corresponding to the measured value can be introduced, and a load greater than the design is not introduced into the sliding bearing type seismic isolation device, so that a predetermined seismic isolation performance can be exhibited.

In addition, the invention described in claims 1 and 2 is a so-called basic seismic isolation method in which a seismic isolation device is arranged under the foundation of an existing building. It can be applied to any so-called intermediate seismic isolation method that installs seismic devices. Therefore, the axial force transmission member between the upper structure and the lower structure in the invention described in claim 2 may be either a pile head or a pillar as described in claims 3 and 4.

It is a vertical front view of the principal part which shows embodiment of this invention. It is a longitudinal front view of the principal part explaining the process following FIG. It is a longitudinal front view of the principal part explaining the process following FIG. FIG. 4 is a longitudinal front view of a main part for explaining a process following FIG. 3. It is a schematic plan view explaining the order of seismic isolation apparatus installation work. It is a vertical front view of the principal part explaining a prior art example. It is a vertical front view of the principal part explaining a prior art example.

Hereinafter, the seismic isolation method for an existing building according to the present invention will be described with reference to the drawings. FIG. 1 shows an excavation below an existing building supported by a pile foundation (existing footing, which may be called a pile head joint or a pile cap in the illustrated example) 1 and the head of a pile 2. After exposing the part
A pressure-resistant panel (mat slab) 3 is constructed on the bottom of the excavation, and the upper structure (existing building above the foundation 1) is provided with a temporary support post (consisting of a steel material 4a and a jack 4b) 4 standing on it. 5, the pile head 2a which is an axial force transmission member between the upper structure 5 and the lower structure 6 is cut and removed in this state, and the pile receiving head 4a when the pile head 2a is cut and removed The first step of measuring the applied load (this is the true building load) with the pressure gauge 7 attached to the jack 4b is shown. 8 is the lowest floor slab, and 9 is a beam. Measured value (actual load) in the first step is the allowable range of the design load (the design load shared by each seismic isolation device and calculated based on the structure of the existing building, finishing load, loading load, etc.) Confirm that it is within the range and proceed with the seismic isolation repair work to the next process.

In the example shown in the figure, since this is a so-called basic seismic isolation method in which a seismic isolation device is installed under the foundation 1 of an existing building, the pile 2 and the pressure platen 3 are collectively referred to as the lower structure 6. However, in the case of the so-called intermediate seismic isolation method in which a base isolation or seismic isolation device is installed at that position by cutting and removing the middle part of the basement or ground floor pillar, The entire structure will be referred to as the lower structure. In the illustrated example, a hydraulic jack is used as the jack 4b, but a screw jack, an air jack, or the like may be used.

FIG. 2 shows a spring bearing type seismic isolation device (in the example shown, a seismic isolation device of a laminated rubber bearing) A as a seismic isolation device with low vertical rigidity. The sliding bearing type seismic isolation device B as a vertical isolation device having high vertical rigidity using orthogonal slide rails (roller bearings) is joined to the lower structure 6 of the existing building and the upper structure 5 The 2nd process installed in the state of joining is shown. Reference numeral 10 denotes an upper frame that connects the spring support type seismic isolation device A and the upper structure 5, and 11 denotes a lower frame that connects the spring support type seismic isolation device A and the lower structure 6. With respect to the seismic isolation device B of the sliding support system, the arrangement of the undercarriage 12 connecting the seismic isolation device B and the lower structure 6 and the concrete placement have been completed, but the upper support 13 connected to the upper structure 5 is arranged. In this state, the upper structure 5 is not yet joined.

FIG. 3 shows unloading (jack down) of the temporary support post 4 corresponding to the seismic isolation device A of the spring support system.
The building load is transferred to the spring bearing type seismic isolation device A, and for the sliding bearing type seismic isolation device B that is not joined to the superstructure of the existing building, the spring bearing type seismic isolation device A By adjusting the pressure of the jack 4b of the temporary support column 4 so that the measured value (actual load) in the first step is maintained at the same time, corresponding to the amount of contraction in the vertical direction due to the loading of Prop 4
The third step is shown in which the building load applied to is held in a constant state (which means that the building load is held within an allowable range and does not necessarily have to be constant in a strict sense).

FIG. 4 shows a temporary support post corresponding to the sliding support type seismic isolation device B after the sliding support type seismic isolation device B is joined to the upper structure 5 of the existing building by placing concrete on the upper base 13. 4 shows the fourth step of unloading (jack down) 4 and transferring the building load to the sliding bearing type seismic isolation device B.

As described above, the upper structure 5 of the existing building is temporarily received by the temporary support column 4 with the jack 4b, and the axial force transmission member between the upper structure 5 and the lower structure 6 is cut and removed in this state, and the removed shaft is removed. A seismic isolation device with different vertical rigidity is installed in each of the axial force transmission paths borne by the force transmission member (in the illustrated example, the place where the axial force transmission member is removed). By shifting the building load from the receiving column to the seismic isolation device, the seismic isolation method for the existing building that performs seismic isolation repair of the existing building is performed by the work procedure of the first process to the fourth process shown in FIGS. By implementing seismic isolation devices A and B
The load transfer due to the difference in vertical stiffness between the seismic isolation devices A and B that may occur in the process of transferring the load to can be prevented, so the load is introduced to the seismic isolation devices A and B with different vertical stiffness as designed. And the specified seismic isolation performance can be demonstrated.

The number and arrangement of seismic isolation devices (spring bearing type seismic isolation device A and sliding bearing type seismic isolation device B) having different vertical rigidity are arbitrarily set according to the conditions of the existing building to be seismically isolated. . Also,
When many seismic isolation devices (spring bearing type seismic isolation device A and sliding bearing type seismic isolation device B) are installed in one existing building, as shown in FIG. It is desirable to perform load transfer in the order of the first work area, the second work area, and the third work area. In the example shown in FIG. 5, first, in the first work area, the load transfer is performed simultaneously for the two spring support type seismic isolation devices A, and then the load transfer to the remaining one of the sliding support type seismic isolation devices B is performed. Next, in the second work area, load transfer is performed simultaneously for the three sliding bearing type seismic isolation devices B,
Next, in the third work area, the load is transferred to the two spring-supporting seismic isolation devices A at the same time, and then the remaining load is transferred to the sliding support-type seismic isolation device B.

Although the present invention has been described based on the illustrated embodiment, the gist of the present invention is not limited to the illustrated embodiment.

A Seismic isolation device with spring support system (Seismic isolation device with low vertical rigidity)
B Seismic isolation device with sliding bearing system (Seismic isolation device with high vertical rigidity)
C Whole building 1 Foundation 2 Pile 2a Pile head 3 Pressure-resistant panel 4 Temporary support post 4a Steel 4b Jack 5 Upper structure 6 Lower structure 7 Pressure gauge 8 Slab 9 Beam 10 Upper base 11 Lower base 12 Lower base 13 Upper base

Claims (4)

This is a seismic isolation method for existing buildings that uses seismic isolation devices with different vertical stiffnesses as seismic isolation devices that are interposed between the upper and lower structures of existing buildings. Of the seismic isolation devices with low vertical rigidity, join the seismic isolation device with low vertical rigidity with the upper structure and lower structure of the existing building, and connect the seismic isolation device with high vertical rigidity with the lower structure of the existing building and Unloading the temporary support struts corresponding to the seismic isolation device with low vertical rigidity in the unconnected state with the superstructure, and for the seismic isolation device with high vertical rigidity in the unconnected state with the superstructure of the existing building, By adjusting the pressure of the jack of the temporary support column, the building load applied to the temporary support column is kept constant, and then the vertical rigidity is increased after joining the seismic isolation device with high vertical rigidity to the superstructure of the existing building. Compatible with high seismic isolation devices Base sinkers method of existing buildings and performing unloading of the strut receiving. The upper structure of the existing building is temporarily received by a temporary support post with a jack, and in this state, the axial force transmission member between the upper structure and the lower structure is cut and removed, and the shaft that the removed axial force transmission member has borne A seismic isolation method for existing buildings, where seismic isolation devices are installed in the power transmission path, and the building load is transferred from the temporary support column to the seismic isolation device. ,
The building load when the axial force transmission member applied to the temporary support struts corresponding to each of the sliding support type seismic isolation device and the spring support type seismic isolation device arranged adjacent to each other is cut and removed is stored in the temporary support post. A first step of measuring with a pressure gauge attached to the jack;
Install the spring support type seismic isolation device on the existing building and joined with the lower structure, and install the sliding support type seismic isolation device on the existing building's lower structure and unconnected with the upper structure. The second step;
Unload the temporary support struts corresponding to the spring bearing type seismic isolation device, and for the sliding support type seismic isolation device that is not joined to the superstructure of the existing building, the jack pressure of the temporary support column A third step of keeping the building load applied to the temporary support column in a constant state by adjusting the measurement value in one step to be held;
A fourth step of unloading the temporary support struts corresponding to the sliding support type seismic isolation device after joining the sliding support type seismic isolation device with the superstructure of the existing building. Seismic isolation method. 3. The seismic isolation method for an existing building according to claim 2, wherein the axial force transmission member is a pile head.   The seismic isolation method for an existing building according to claim 2, wherein the axial force transmission member is a pillar.

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