JP3648670B2 - Seismic isolation device installation method for existing foundation deep piles - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a seismic isolation device installation method for an existing building deep foundation pile.
[0002]
[Prior art]
As an earthquake countermeasure, the need to install a seismic isolation device at the foundation of a building is increasing, but in the case of an existing building, it is not easy to incorporate the seismic isolation device into the foundation. If it is a small-scale building at the bottom, for example, the building can be separated from the foundation and pushed up, and after installing the seismic isolation device on the foundation, the building can be lowered and integrated with the seismic isolation device. Such a construction method cannot be applied to high-rise buildings. For this reason, usually, means such as refurbishing the wall part and incorporating an earthquake-resistant mechanism such as a damper are adopted.
[0003]
[Problems to be solved by the invention]
However, there is a problem that it is not always possible to expect a sufficient seismic effect for a large earthquake if the conventional method is to incorporate an earthquake-resistant mechanism in the wall portion.
The present invention is made in order to solve such a conventional problem, and even when a large-scale existing high-rise building has a deep foundation pile, an earthquake-resistant mechanism is used for the foundation using the deep foundation pile. The purpose is to provide a method for installing seismic isolation devices on existing piles.
[0004]
[Means for Solving the Problems]
As a means for achieving this object, the present invention excavates so that the head of the deep foundation pile is exposed in the existing building having the deep foundation pile, and cuts and removes leaving the central portion of the head, A jack is installed at the cut location to receive the foundation of the existing building, and then the center is cut and removed, a pressure plate is formed on the upper end of the deep pile, and the cut and removed center is exempted. The gist is to install the seismic device and integrate it with the foundation, and then remove the jack after transferring the load of the existing building to this seismic isolation device.
In addition, in this seismic isolation device installation method, when forming a pressure-resistant plate, a lower anchor plate is installed as a base isolation frame, and a seismic isolation device is installed on the lower anchor plate. The gist is that the concrete is pressed into the gap and integrated.
[0005]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
In Fig. 1 (a), 1 is a deep foundation pile of an existing building (not shown). A foundation part 2 is formed at the top of the pile and an underground beam 3 intersects in a cross shape as shown in (b). Attached. The 1st process of this invention construction method excavates predetermined depth L (about 1.5m-2.0m) from the bottom face of foundation part 2, and exposes the head of deep foundation pile 1. This excavation can be performed from outside the building by machine or human power.
[0006]
In the second step, a part of the exposed head of the deep foundation pile 1 is removed. As shown in FIGS. 2 (a) and 2 (b), a predetermined portion of the deep foundation pile 1 is cored to form a wire setting hole 1a, and the central portion 1b of the deep foundation pile 1 is left and both sides thereof are formed. The parts 1c and 1d are removed by cutting C with a wire saw (not shown). At this time, the remaining cross section of the central portion 1b has an area necessary and sufficient to support the load of the existing building.
[0007]
In the third step, a plurality of oil jacks 5 are arranged on both sides 1c and 1d that have been cut and removed via a concrete mount 4 as shown in FIGS. I do. That is, the base portion 2 is stably received by the plurality of oil jacks 5 to temporarily support the existing building.
[0008]
The fourth step is the removal of the central part 1b of the deep foundation pile 1, which is performed by moving the upper and lower parts of the central part 1b remaining on the head of the deep foundation pile 1 as shown in FIGS. 4 (a) and 4 (b). Cut and remove with a wire saw.
[0009]
In the fifth step, as shown in FIGS. 5A and 5B, the pressure plate 6 is formed on the upper portion of the deep pile 1 including the concrete mount 4. The pressure plate 6 is formed by placing reinforcing bars and placing concrete. At that time, a lower anchor plate 7 serving as a base isolation frame is installed, and a base isolation device 8 is installed thereon. Furthermore, concrete is press-fitted into the gap between the seismic isolation device 8 and the base portion 2 to form an upper anchor plate 9 to be integrated with the base portion 2.
[0010]
In the sixth step, the load on the existing building is transferred to the seismic isolation device 8 to remove the temporary support material. That is, as shown in FIGS. 6A and 6B, the oil jack 5 is unloaded, and after the building load is transferred to the seismic isolation device 8, the oil jack 5 is completely removed. The concrete mount 4 is left behind, or the protrusion is removed so that it is flush with the upper surface of the pressure plate 6.
[0011]
The seismic isolation device 8 can be incorporated between the foundation portion 2 and the deep foundation pile 1 of the existing building through such a process. In this case, since the seismic isolation device 8 is interposed in the foundation 2 of the existing building, a sufficient seismic isolation effect can be exhibited during a large earthquake.
[0012]
【The invention's effect】
As described above, according to the present invention, the seismic isolation device can be incorporated between the foundation portion and the deep foundation pile of the existing building using the deep foundation pile of the existing building, Construction of the building is easy because the state of its ridges is maintained and only the upper end of the deep foundation pile is repaired. Therefore, it can be applied to a large-scale existing high-rise building.
[Brief description of the drawings]
FIG. 1 shows a first step of a seismic isolation device installation method according to the present invention, in which (A) is a sectional view and (B) is a plan view.
FIGS. 2A and 2B show a second step, where FIG. 2A is a cross-sectional view and FIG. 2B is a plan view of an upper portion of a deep foundation pile.
FIGS. 3A and 3B show a third step, where FIG. 3A is a cross-sectional view and FIG. 3B is a plan view of an upper portion of a deep foundation pile.
FIGS. 4A and 4B show a fourth step, where FIG. 4A is a cross-sectional view and FIG. 4B is a plan view of an upper portion of a deep foundation pile.
FIGS. 5A and 5B show a fifth step, where FIG. 5A is a cross-sectional view and FIG. 5B is a plan view of an upper portion of a deep foundation pile.
FIG. 6 shows the sixth step, in which (a) is a cross-sectional view and (b) is a plan view of an upper portion of a deep foundation pile.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Deep foundation pile 2 ... Foundation part 3 ... Underground beam 4 ... Concrete mount 5 ... Oil jack 6 ... Pressure-resistant plate 7 ... Lower anchor plate 8 ... Seismic isolation device 9 ... Upper anchor plate

Claims (2)

In an existing building with deep foundation piles, excavate so that the head of the deep foundation pile is exposed, cut and remove leaving the center of the head, and install a jack at the cut location to install the foundation of the existing building Then, the central part is cut and removed, and a pressure-resistant plate is formed on the upper end of the deep foundation pile, and a seismic isolation device is installed in the cut and removed central part to integrate it with the foundation part. A seismic isolation device installation method for existing building deep piles, which removes jacks after transferring the load of the existing building to the seismic device. When forming a pressure-resistant plate, install a lower anchor plate as a base isolation frame, install a seismic isolation device on the lower anchor plate, and press the concrete into the gap between the seismic isolation device and the foundation to integrate them. The seismic isolation apparatus installation method to the existing building deep foundation pile of Claim 1.

Images