JPH09125705A - Method for introducing base isolation to existing building - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify the works by excavating the ground under a building foundation, exposing existing piles, forming a new foundation using a plurality of piles in a lump, cutting the upper parts of some piles for installation of a base isolation device, and then cutting off the remaining piles. SOLUTION: Existing piles 2 are exposed by excavation, and thereto anchors 6, reinforcing members 7, etc., are fixed, and a new foundation 5 is constructed with concrete while a space for installation of a base isolation device 9 is reserved. The upper parts of some piles constituting an obstacle for installation of the base isolation device 9 are cut off, and there the base isolation 9 is installed and supported by a provisionally mounted jack. After the installation, the remaining piles 2 are cut off followed by removal of the jack, and the foundation 15 of the existing building 1 is borne by the base isolation 9, which should be executed so that it is not needed to support the whole existing building 1 provisionally with steel pipe piles, etc. This simplifies the works and achieves the reduction of the costs.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a construction method for seismically isolating an existing building with pile foundations.

[0002]

2. Description of the Related Art Conventionally, as a construction method for seismic isolation of an existing building, a construction method understood from FIGS. 19 to 24 has been generally used. That is, first, after constructing a mountain wall, the lower part of the existing building is excavated to expose the peripheral part of the existing pile to the outside (see FIG. 1).
9).

Next, at a position outside the existing existing pile, the temporary support pile is mounted (FIG. 20). After that, all the existing piles are cut, and a new foundation is formed above the cut place (Fig. 21). Further, the seismic isolation device is installed between the lower surface of the existing building and the upper surface of the new foundation (Fig. 22), and the seismic isolation device is applied by a flat jack or the like to fill the grout above the seismic isolation device (Fig. 23).

Finally, the temporary support piles, flat jacks, etc. are removed to complete seismic isolation.

[0005]

However, in such a conventional construction method, it is necessary to attach and implement a temporary support pile such as a steel pipe pile for temporarily supporting the entire existing building, and the work is troublesome. There was a problem that construction costs would increase. Further, conventionally, since an existing building is supported by a temporary support pile such as a steel pipe pile, there is a problem when a large external force such as a large earthquake acts on the existing building when cutting all the existing piles.

Thus, the present invention was devised to address the above-mentioned problems, and it is not necessary to attach and implement a temporary support pile such as a steel pipe pile for temporarily supporting the entire existing building, and seismic isolation work is performed. Can be performed easily and the construction cost can be reduced accordingly. Another object of the present invention is to provide a seismic isolation construction method for an existing building that does not have a problem when a large external force such as a large earthquake acts on the existing building when cutting all the existing piles as in the conventional case.

[0007]

A seismic isolation method for an existing building according to a first aspect of the present invention excavates a lower portion of an existing building to expose an existing pile that supports the existing building, and then the existing pile is placed inside. Forming a new foundation by burying it, of the existing piles exposed between the upper surface of the new foundation and the lower surface of the existing building, the piles that obstruct the installation of the seismic isolation device are cut and the seismic isolation device is attached. After that, the remaining existing piles are cut, and the seismic isolation method for the existing building according to the second invention exposes the existing piles supporting the existing building, and the uneven surface generating material is provided on the outer peripheral surface of the existing piles. Form the foundation by bonding and burying it, and attach the seismic isolation device by cutting the pile that interferes with the installation of the seismic isolation device among the existing piles exposed between the upper surface of the foundation and the lower surface of the existing building. And then cutting the remaining existing piles, The seismic isolation method for an existing building according to the third aspect of the present invention exposes a plurality of existing piles supporting the existing building, adheres the uneven surface generating material to the outer peripheral surface of the existing pile, and bonds the uneven surface generating material. A new concrete foundation is formed by burying the existing piles, and among the existing piles exposed between the upper surface of the new concrete foundation and the lower surface of the existing building, the pile that obstructs the installation of the seismic isolation device is cut off. After installing the seismic isolation device and then cutting the remaining existing piles, the seismic isolation device and the existing building are connected to the seismic isolation device and the existing building with anchors protruding from each of the existing building and the seismic isolation device. The seismic isolation method for an existing building according to the fourth aspect of the present invention exposes a plurality of existing piles supporting the existing building, Bond the uneven surface generating material to the outer peripheral surface of the pile. Rutotomoni, by burying the existing pile adhered an irregular surface produced material to form the concrete foundation of the new, of the existing pile exposed between the existing buildings lower surface and said new concrete foundation upper surface,
The piles that interfere with the installation of the seismic isolation device are cut, the seismic isolation device is attached, and then the remaining existing piles are cut, and the cutting upper surface of the cut existing piles is provided with a reinforcement member for preventing protrusion. It is configured to have been done.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of the present invention will be described below with reference to the drawings. First, the outline of the present invention is shown in FIGS. That is, after the construction of the cliff wall, the lower part of the existing building 1 is excavated to expose the existing piles 2 ... Peripheral portion to the outside (FIG. 13).

Next, the adhesive 3 is applied to the exposed outer peripheral surface of the existing piles 2 ... And the crushed aggregates 4 are adhered (FIG. 13). It should be noted that the crushed aggregates 4 may be adhered at a height up to the location where the new foundation 5 to be described later is created. After that, crushed aggregate 4
The new foundation 5 is formed by burying the existing piles 2 ... As shown in FIG. 14, the shape of the new foundation 5 is a square-shaped mountain, and there is a space between the upper portion of the new foundation 5 and the lower portion of the existing foundation 15 such that the seismic isolation device 9 can be installed. I will keep it.

In order to secure a space for installing the seismic isolation device 9, the existing pile 2 located substantially at the center is cut (FIG. 15) and the seismic isolation device 9 is temporarily installed at the cut location. Yes (Fig. 16). Then, a jack is applied to the seismic isolation device to fill the grout above the seismic isolation device 9 and the jack is removed after the grout has solidified,
Concrete is filled around the grout (Fig. 17), and then the remaining existing piles 2 ... Are cut off to complete the main installation of the seismic isolation device 9, thus ending the seismic isolation of the existing building 1. Let them do it.

The present invention will be described more specifically based on the outline of the present invention. The seismic isolation method of the existing building 1 in the case where the number of existing piles 2 is 5 will be described with reference to FIGS. 1 and 2. First, the lower part of the existing building 1 is excavated up to the excavation line indicated by symbol H in FIG. 2, and the five existing piles 2 ... Are exposed to the outside.

After that, the adhesive 3 is applied to the exposed outer peripheral surfaces of the existing piles 2 ... And the crushed aggregate 4 ... Is adhered to the surface (FIGS. 13 and 14). The length of the crushed aggregates 4 ... Can be up to the height at which the new foundation 5 is formed. Then, after confirming the adhesion of the crushed aggregate 4, ..., The new foundation 5 is formed by burying the five existing piles 2 ,.

Since the crushed aggregates 4 ... Are adhered to the outer peripheral surface of the existing piles 2 ..., The new foundation and the existing piles 2 ...
Adhesion with ... becomes good, and even after many years of use, cracks, gaps, upward protrusion of the existing piles 2, etc. will not occur. As can be seen from FIG. 2, in the new foundation 5, in the outer direction of the seismic isolation device 9 installed, the remaining existing piles 2 to be finally cut are ... ... is buried in advance.

As will be described later, when the remaining existing piles 5 ... Are cut, the reinforcing member 7 is covered so that the cut upper surface of the cut existing piles 5 ... Does not rise. The anchor members 6 ... Are provided with a connecting portion 8 so that they can be connected to the reinforcing member 7. Usually, this connecting portion 8 is configured as a coupler, and by screwing a screw-shaped connecting member from the reinforcing member 7, the reinforcing member 7 can be firmly fixed to the cut upper surface of the existing pile 2.

After the new foundation 5 is formed and fully solidified, the seismic isolation device 9 is installed. The structure of the seismic isolation device 9 is not limited in any way, and a generally used one is used. Here, as understood from the figure, an iron plate-shaped lower plate 10 laid on the upper surface of the new foundation 5, and an iron plate 11 and a rubber sheet 12 on the lower plate 10.
Are alternately laminated to have a substantially cylindrical thickness, and an iron plate-shaped upper plate 13 is mounted thereon to configure the seismic isolation device 9 as a so-called laminated rubber bearing.

Therefore, grout is injected between the seismic isolation device 9 and the existing foundation 15 of the existing building 1,
The jointed body 14 is formed by filling the jointed body 1.
The seismic isolation device 9 and the existing foundation 15 are joined together via 4 as follows. That is, the anchor members 6 that are respectively projected from the seismic isolation device 9 and the existing foundation 15 ...
. Is extended into the joint structure 14 and embedded and fixed in the joint structure 14.

Here, a plurality of reinforcing bars are arranged in the existing foundation 15, and when the long anchor member 6 projects directly into the existing foundation 15 from the seismic isolation device 9 side, the existing foundation 15 is Therefore, the seismic isolation device 9 and the existing foundation 15 cannot be satisfactorily connected. Therefore, in the present invention, the joint frame 14 is provided, and the anchor members 6 ... Protruding from the seismic isolation device 9 and the existing foundation 15 are extended into the joint frame 14 and embedded and fixed in the joint frame 14. is there. As a result, a good connection between the seismic isolation device 9 and the existing foundation 15 can be obtained by quick and simple construction work.

Next, as shown in FIGS. 3 and 4, the case where the number of existing piles 2 is 4 will be described. In this case, 4 existing piles 2
It is assumed that any one of these is cut and the seismic isolation device 9 is installed from the cut position. However, the construction work other than that is the same as the case where the number of the existing piles 2 is five. Further, FIGS. 5 and 6 show the case where there are six existing piles 2. In this case, as shown in the figure, the two central piles are cut first and the seismic isolation device 9 is installed. It is said that.

In the case of this embodiment, the new foundation 5 is formed into a substantially rhombic shape when viewed from above and is cut into 2 pieces.
Reinforcing piles 16 and 16 are erected on the outside of the existing piles 2 and 2, respectively, and are reinforced as shown in FIG. The reinforcement piles 16 and 16 are embedded in the new foundation 5, but after the seismic isolation device 9 is installed, the exposed portions of the jack 17 and the reinforcement pile 16 are cut off.

In this embodiment, a split type reinforcing pile 16 is provided so as to be easily cut. 7 and 8 show the case where there are three existing piles 2, and in this case, any one of the three piles 1
It is supposed that the book is cut, and the seismic isolation device 9 is installed from the cut position, and the reinforcing pile 16 is erected on the outside of the existing one pile 2 that has been cut and reinforced as shown in FIG. It

FIGS. 9 and 10 show a case where there are two existing piles 2. In this case, two piles are to be cut, and
Reinforcement piles 2 and 2 which are not buried in the new foundation 5 are erected as shown in the figure. And finally, the reinforcement piles 2 and 2 are removed. 11 and 12 show a case of one existing pile 2. In this case, a temporary support work 18 and a temporary jack 19 are used, and after cutting the existing pile 2 and installing the seismic isolation device 9, The temporary support work 18 and the temporary jack 20 are removed.

[0022]

The present invention has the above construction. Further, according to the seismic isolation method for an existing building according to the present invention, it is not necessary to install and implement a temporary support pile such as a steel pipe pile that temporarily supports the entire existing building, and seismic isolation work can be easily performed. The construction cost can be reduced.

Further, unlike the conventional case, there is no problem when a large external force such as a large earthquake acts on the existing building when cutting all the existing piles.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram (1) showing a configuration of the present invention.

FIG. 2 is an explanatory diagram (part 2) showing the configuration of the present invention.

FIG. 3 is an explanatory diagram (part 3) showing the configuration of the present invention.

FIG. 4 is an explanatory diagram (Part 4) showing the configuration of the present invention.

FIG. 5 is an explanatory diagram (Part 5) showing the configuration of the present invention.

FIG. 6 is an explanatory view (No. 6) showing the configuration of the present invention.

FIG. 7 is an explanatory view (No. 7) showing the configuration of the present invention.

FIG. 8 is an explanatory diagram (Part 8) showing the configuration of the present invention.

FIG. 9 is an explanatory diagram (Part 9) of the configuration of the present invention.

FIG. 10 is an explanatory view (No. 10) showing the configuration of the present invention.

FIG. 11 is an explanatory diagram (Part 11) showing the configuration of the present invention.

FIG. 12 is an explanatory view (12) showing the configuration of the present invention.

FIG. 13 is an explanatory diagram (1) showing the schematic process of the present invention.

FIG. 14 is an explanatory diagram (2) showing the schematic process of the present invention.

FIG. 15 is an explanatory diagram (3) showing the schematic process of the present invention.

FIG. 16 is an explanatory diagram (4) showing the schematic process of the present invention.

FIG. 17 is an explanatory view (No. 5) showing the schematic process of the present invention.

FIG. 18 is an explanatory view (No. 6) showing the schematic process of the present invention.

FIG. 19 is an explanatory diagram (1) showing a schematic process of a conventional example.

FIG. 20 is an explanatory diagram (part 2) showing a schematic process of a conventional example.

FIG. 21 is an explanatory view (No. 3) showing the schematic steps of the conventional example.

FIG. 22 is an explanatory view (No. 4) showing the schematic steps of the conventional example.

FIG. 23 is an explanatory view (No. 5) showing the schematic process of the conventional example.

FIG. 24 is an explanatory view (No. 6) showing a schematic process of a conventional example.

[Explanation of symbols]

 1 Existing Building 2 Existing Pile 3 Adhesive 4 Crushed Aggregate 5 New Foundation 6 Anchor Member 7 Reinforcement Member 8 Connection 9 Seismic Isolation Device 10 Lower Plate 11 Iron Plate 12 Rubber Sheet 13 Upper Plate 14 Joined Frame 15 Existing Foundation 16 Reinforcement Pile 17 Jack 18 Temporary support work 19 Temporary jack H excavation line

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Hidehiko Miyanaga 2 Sanbancho, Chiyoda-ku, Tokyo, Tobishima Construction Co., Ltd. (72) Inventor Masaharu Kubota 2 Sanbancho, Chiyoda-ku, Tokyo Tobishima Construction Co., Ltd. Within

Claims (4)

[Claims] 1. Excavating a lower part of an existing building to expose an existing pile that supports the existing building, and then burying the existing pile inside to form a new foundation, and the upper surface of the new foundation and the lower surface of the existing building. Of the existing piles exposed during the period, the piles that interfere with the installation of the seismic isolation device are cut and the seismic isolation device is installed, and then the remaining existing piles are cut off. Seismic method. 2. Exposing an existing pile supporting an existing building,
Among the existing piles exposed between the upper surface of the foundation and the lower surface of the existing building, the seismic isolation device will be obstructed while the uneven surface generating material is adhered to the outer peripheral surface of the existing pile to be buried. A seismic isolation method for existing buildings characterized by cutting the piles and installing seismic isolation devices, and then cutting the remaining existing piles. 3. A new concrete structure in which a plurality of existing piles supporting an existing building are exposed, and a concavo-convex surface generating material is adhered to the outer peripheral surface of the existing piles, and at the same time, existing concavities to which the concavo-convex surface generating material is adhered are buried. Forming a foundation, among the existing piles exposed between the upper surface of the new concrete foundation and the lower surface of the existing building, the piles that obstruct the installation of the seismic isolation device are cut and the seismic isolation device is attached to the space, and then,
The remaining existing piles are cut, and the seismic isolation device and the existing building are joined by a seismic isolation device and an anchor protruding from the existing building, which is formed between the seismic isolation device and the existing building. A seismic isolation method for existing buildings, which was characterized by being fixed by being buried in the building. 4. A new concrete structure in which a plurality of existing piles supporting an existing building are exposed, an uneven surface generating material is adhered to an outer peripheral surface of the existing pile, and the existing pile to which the uneven surface generating material is adhered is buried. Of the existing piles that form the foundation and are exposed between the upper surface of the new concrete foundation and the lower surface of the existing building, the piles that obstruct the installation of the seismic isolation device are cut to install the seismic isolation device, and then the remaining existing This is a seismic isolation method for existing buildings, which is made by cutting the piles, and a reinforcing member for preventing protrusion is provided on the cut upper surface of the existing piles.