JPH0762896A - Upper part extension method for building - Google Patents

Abstract

PURPOSE:To limit the reinforcement of a skeleton which constitutes a building to a level of reinforcement work which complies with a long time vertical load based on an increased weight equivalent to an extended space and thereby secure an existing living space and reduce construction cost as well as a construction period and further eliminate the need to live temporarily in the other house for a long time CONSTITUTION:This invention relates to an upper floor extension work method of a building which provides a building 1 and a foundation 2 which supports the building 1 and reinforces an existing skeleton 1a which constitutes the building skeleton 1. An existing foundation which supports the building skeleton 1 is reinforced by constructing an extended foundation 4. A damper device is installed between the building skeleton 1 and the foundation. Extension work is executed on the upper part of the building 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for constructing an upper part of a building suitable for use as a technique for constructing an additional part on the upper part of an existing building having a building and a foundation for supporting the building.

[0002]

2. Description of the Related Art For example, in collective housing such as apartments and condominiums, or in buildings such as tenants, it is becoming difficult for residents to live because of aging of buildings, lack of functions, and poor usability. . Especially in the housing complex built in 1940s-1940s,
Many of them are old and have a small floor area, so there is a high need for rebuilding. However, in reality, due to the cost of construction work and the cost of temporary housing during construction, the reality is that it is difficult to realize.

[0003]

Therefore, there is a method of adding an extension to such an existing building, but this has the following problems. When adding to an existing building,
Due to the increase in weight associated with the extension, a large amount of seismic reinforcement work is required for the existing parts such as the building structure and foundation. In other words, this reinforcement work requires not only reinforcement for long-term vertical loads based on the increase in weight of the extension, but also seismic reinforcement work for earthquakes, etc.
Therefore, there is a problem that the valuable living space is narrowed by increasing the wall thickness of the building itself and adding a reinforcing frame. Further, since the reinforcement work becomes large-scale, there is a problem that the construction cost is increased and the construction period is prolonged.

The present invention has been made in consideration of the above points, and it is possible to limit the reinforcement of the skeleton constituting the building to the extent of the reinforcement work against the long-term vertical load based on the increase in the weight of the extension. In this way, it is intended to provide an upper extension construction method for a building that can secure an existing living space, reduce construction costs, shorten the construction period, and even make it unnecessary to temporarily live in another residence for a long time.

[0005]

The invention according to claim 1 is
A method of constructing an upper part of a building including a building and a foundation that supports the building, the step of reinforcing an existing frame that constitutes the building, and the step of reinforcing the existing foundation that supported the building by constructing the additional foundation. And a step of installing a seismic isolation device between the building and the foundation, and a step of performing an extension work on the upper part of the building.

According to a second aspect of the present invention, in the method for constructing an upper part of a building according to the first aspect, the part of the additional construction on the upper part of the building is a steel frame structure.

[0007]

According to the first aspect of the present invention, when the upper part of the building is extended, the existing foundation is reinforced by the construction of the additional foundation, and the seismic isolation device is installed between the foundation and the building. Therefore, the seismic isolation device suppresses the increase in seismic force of the building that has been expanded. Therefore, it is possible to eliminate the seismic retrofitting, or to eliminate it, which enables the building structure to be reinforced only to the extent of reinforcement work for long-term vertical loads based on the increased weight of the added building. .

According to the second aspect of the present invention, when the additional construction part of the upper part of the building is made of steel frame, the weight is sufficiently lighter than that of the case of reinforced concrete structure, so that the increase in seismic force of the new building is almost eliminated. Therefore, the seismic retrofitting can be made lighter, or can be eliminated.

[0009]

Embodiments of the present invention will be described below with reference to the accompanying drawings. 1 to 4 show an example of a construction procedure of an upper extension construction method for a building according to this embodiment. In these drawings, reference numeral 1 indicates a building of an existing building, and reference numeral 2 indicates a building. It is an existing foundation that supports 1. In FIG. 1, the building 1 of the building to be expanded is
In this embodiment, a four-story RC (reinforced concrete) structure is shown, and for the foundation 2, a foundation pile 3 having a depth that reaches the ground support layer (not shown) such as a hard rock layer is constructed. What is done is shown.

When the building 1 is extended, first, the existing frame 1a portion of the building 1 is reinforced. In this reinforcement work, depending on how many floors and how much weight is added to the upper part of the building 1, at least reinforcement work against long-term vertical load based on the increase in the weight of the addition will be carried out. Keep it. Here, if necessary, some seismic retrofitting work will also be carried out on the structure 1a.

Next, in addition to the existing foundation 2 that supports the building 1, an extension foundation 4 and extension piles 5 are constructed as shown in FIG. When constructing the additional foundation 4 and the additional pile 5, it is sufficient to dig down the ground G within such a height and working space as to allow the additional foundation 4 and the additional pile 5 to be constructed. Here, when the height of the work space is further required, as shown in FIG. 2, the existing foundation 2 and the building 1
The building 1 may be jacked up by a jack 6 disposed between

Next, as shown in FIG. 3, a seismic isolation device 7 is installed between the reinforced building 1 and the foundation 2 including the extension foundation 4. 2 and 3 when installing the seismic isolation device 7.
As shown in FIG. 2, the building 1 is supported by a plurality of jacks 6 arranged between the building 1 and the foundations 2 and 4, and then the building 1 and the foundation are separated, and the building 1 is jacked up. After installing the seismic isolation device 7, you can jack down. In this case, the jack 6
A support structure (not shown) that can temporarily support the building 1 using steel or the like is also used as the foundation 2
It is desirable to provide it around the.

As the seismic isolation device 7, for example, a building rubber is installed under a building pillar to support a vertical load of the building, and at the time of an earthquake, a damper (damping mechanism) incorporated in the building rubber or attached independently. A damper that suppresses the displacement amplitude is used in combination.

After reinforcement of the skeleton, construction of the extension foundation, and installation of the seismic isolation device have been carried out in this manner, then an extension floor 8 is constructed on the upper part of the building 1 as shown in FIG. It is preferable that the extension floor 8 is made of steel in order to reduce the weight in addition to the workability of the extension.

FIG. 5 shows an extension by the conventional construction method when an extension of two layers is performed on the upper part of the existing building and a seismic isolation construction method (MR) by installing the seismic isolation device 7 as in this embodiment. (1) Construction method) and the existing part only are shown as a comparison of the design seismic load with the design seismic layer shear force (when the existing part and the additional part are RC structures). .

As can be seen from FIG. 5, due to the seismic isolation effect of the seismic isolation device 7, the increase in seismic force due to the increase in weight due to the extension is only a slight increase with respect to the seismic force of the existing part only. However, if the extension is constructed of a lightweight structure such as a steel frame, such an increase in seismic force will almost disappear. Therefore, by installing the seismic isolation device 7 between the existing building and the foundation as in the embodiment,
It is necessary to reinforce the existing frame and the foundation for the long-term vertical load due to the increase in the weight of the extension, but with regard to the seismic retrofitting, it will be possible to eliminate it by the seismic isolation effect, or eliminate it.

Therefore, the reinforcement of the existing frame can be limited to a slight reinforcement work against a long-term vertical load due to the increase in the weight of the extension, thereby securing the existing living space, reducing the construction cost, and shortening the construction period. In addition, since the construction can be completed and the construction can be continued even if the minor construction work of the existing construction is completed, the resident does not need to temporarily live in another residence for a long time. Also,
Since the added building has improved safety during an earthquake due to the action of the seismic isolation device, it also has the effect of increasing added value and durability.

In the examples, the construction method for expanding the RC (reinforced concrete) building was explained, but it goes without saying that the present invention can be applied to SRC (steel frame reinforced concrete) and S (steel frame) buildings. .

[0019]

As described above, according to the method for constructing an upper part of a building in the present invention, the following excellent effects can be obtained.

In the upper extension construction method for a building according to claim 1, a step of reinforcing an existing frame forming the building, and a step of reinforcing an existing foundation supporting the building by constructing an extension foundation, Since the structure includes a step of installing a seismic isolation device between the building and the foundation, and a step of performing an extension work on the upper part of the building, it is possible to reinforce the structure of the building by the action of the seismic isolation device. It is possible to limit the amount of reinforcement work to the long-term vertical load based on the increase in the weight of the extension, thereby ensuring the existing living space, reducing the construction cost, shortening the construction period, increasing the added value, increasing the durability, etc. It is also possible to eliminate the need for temporary housing in another residence for a long time. Further, since the seismic isolation device is installed at the time of extension, there is an effect that the work can be performed in parallel with the time of extension.

According to the building top extension method of claim 2, in the case of the building top extension method of claim 1, when the construction part of the building top is made of steel frame, compared to the case of reinforced concrete construction. It ’s light enough,
Almost no increase in the seismic force of the newly built building can be eliminated, which allows for minor or no seismic retrofitting.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view of an existing building shown to explain an embodiment of the present invention.

FIG. 2 is a schematic sectional view showing an embodiment of the present invention.

FIG. 3 is a schematic sectional view showing an embodiment of the present invention.

FIG. 4 is a schematic sectional view showing an embodiment of the present invention.

FIG. 5 is a graph showing a design seismic layer shear force per unit floor area shown for explaining an example of the present invention.

[Explanation of symbols]

 1 Building 1a Frame 2 Existing foundation 3 Existing foundation pile 4 Extension foundation 6 Jack 7 Seismic isolation device 8 Extension floor

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kikuo Toyoshima 2-10-10 Fujimi, Chiyoda-ku, Tokyo Maeda Construction Industry Co., Ltd.

Claims (2)

[Claims] 1. A method for constructing an upper part of a building including a building and a foundation for supporting the building, the method comprising: a step of reinforcing an existing frame forming the building; An upper extension construction method for a building, comprising: a step of reinforcing the foundation; a step of installing a seismic isolation device between the building and the foundation; and a step of performing an extension work on an upper portion of the building. 2. The method for constructing an upper part of a building according to claim 1, wherein the portion for constructing the upper part of the building is a steel structure.