JP3609203B2 - Seismic isolation foundation construction method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a construction method for a base of a base isolation structure in a building such as a house.
[0002]
[Prior art]
Conventionally, the foundations of residential buildings have been constructed by placing foundations in the form of tangling with the local industry, such as piles that have been installed to the depth of the hard layer of the ground. And when building was made into a base isolation structure, the building was built on this foundation via the base isolation member.
[0003]
[Problems to be solved by the invention]
However, in the case of the conventional seismic isolation structure, since the building body is built on the seismic isolation member, it is difficult to construct the same way as the conventional method of building the building body on the foundation, and the construction cost is low. Inconveniences such as bulkiness occur.
[0004]
Moreover, since the foundation and the building body are not integrated, there arises a disadvantage that the rigidity of the building body is lowered.
[0005]
Furthermore, in soft ground, foundations have been established on the ground such as piles that have been cast to the hard layer of the ground, but in the event of a large-scale earthquake disaster, the piles and foundations will be displaced. Will end up on a soft ground. Therefore, even if the building on the foundation is safe, the pile and the foundation are displaced from each other, resulting in inconvenience that the building becomes unstable on the soft ground or is distorted with the foundation.
[0006]
This invention is made | formed in view of the actual condition which concerns, Comprising: It aims at providing the construction method of the seismic isolation foundation which can be set as a base isolation structure from a foundation part.
[0007]
[Means for Solving the Problems]
The construction method of the seismic isolation foundation of the present invention for solving the above-mentioned problem is to fix the seismic isolation member on the groundwork arranged at the root cut, and on the seismic isolation member on the inner side of the lid surface. A fitting part that covers a covered cylindrical lid with a rib for positioning the seismic member, and fits the seismic isolation member into the rib, or engages the seismic isolation member and the lid with each other. By covering the lid-shaped cylindrical lid so as to match them, an equal gap is formed between the seismic isolation member and the peripheral surface of the lid body, up to the position of the top surface of this lid body, The foundation is placed on the lid so that the earth and sand are backfilled around the lid and a reinforcing bar protruding from the top surface of the lid is buried.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0009]
FIG. 1 shows an outline of the construction process of the seismic isolation foundation.
[0010]
That is, in this construction method of the base isolation base, the base isolation member 2 is provided on the top surface of the steel pipe pile 1 and the base 4 is placed on the lid body 3 covered with the base isolation member 2.
[0011]
The steel pipe pile 1 is made of a steel pipe having a certain length, and is driven while being added one after another from the soft layer 51 to the hard layer 52 of the ground 5. And it cut | disconnects in the position of the root cutting bottom 53, and the iron plate 11 is welded so that the cutting | disconnection opening surface may be plugged up.
[0012]
In addition, in this Embodiment, although the steel pipe pile 1 is used, it is not limited to such a steel pipe pile 1, As shown in FIG. 2, it is the steel pile 1a which consists of H-shaped steel, for example. Alternatively, it may be a concrete pile 1b, a reinforced concrete pile 1c, a composite pile 1d in which concrete is placed in a steel pipe, a soil improvement pile 1e formed by filling the ground with a hardener and improving the soil in a columnar shape, and the like.
[0013]
The seismic isolation member 2 is made of an elastomer formed in a substantially cylindrical shape, and a cylindrical concave portion 21 that matches the steel pipe pile 1 is formed at the bottom thereof. The seismic isolation member 2 is attached to the steel pipe pile 1 by fitting the recessed portion 21 to the tip of the steel pipe pile 1.
[0014]
Moreover, as shown in FIG. 2, when attaching to the steel material pile 1a or the composite pile 1d, it can attach similarly by setting it as the shape of the recessed part 21 matched with these shapes. Furthermore, when attaching to the concrete pile 1b and the reinforced concrete pile 1c, it can attach similarly by previously forming the projection part 22 which corresponds to the recessed part 21 at the time of concrete placement. Further, in the case of the soil improvement pile 1e, the needle portion 23 of the pedestal 24 having the needle portion 23 is inserted into the soil improvement pile 1e, and the recessed portion 21 is fitted into the protrusion portion 25 protruding from the pedestal 24. Can be attached by.
[0015]
The lid 3 is formed in a cylindrical shape with a lid, and a reinforcing bar 31 for embedding in the foundation 4 projects from the lid surface 30. The lid 3 is covered so as to cover the seismic isolation member 2, and a uniform gap D is formed between the lid 3 and the seismic isolation member 2. At this time, as shown in FIG. 3A, a circular rib 32 for positioning the seismic isolation member 2 is provided on the inner side of the lid surface 30 of the lid 3, and the seismic isolation member is provided in the rib 32. 2 is fitted, and the cover 3 is covered, so that the gap D between the seismic isolation member 2 and the cover 3 is made uniform. Further, as shown in FIG. 3B, a positioning member 6 such as a sponge is attached around the seismic isolation member 2, and the lid 3 is further covered from the positioning member 6, so that the seismic isolation member 2 and the lid 3 are covered. It is good also as the gap | interval D between these being equal. Further, as shown in FIGS. 3 (c) and 3 (d), the seismic isolation member 2 and the lid body 3 are provided with fitting portions 26 and 33 for fitting the concave and convex portions to each other, and the lid is arranged so as to match them. By covering the body 3, the gap D between the seismic isolation member 2 and the lid 3 may be made uniform.
[0016]
In this way, the earth and sand 54 is buried in the root cutting bottom 53 so as to reach the position of the lid surface 30 of the lid 3 around the lid 3 covered with the seismic isolation member 2.
[0017]
Then, the foundation 4 is driven so that the reinforcing bar 31 protruding from the lid surface 30 of the lid end 3 is embedded. At this time, the number and positions of the steel pipe piles 1, seismic isolation members 2, and lids 3 are determined according to the building constructed on the foundation 4. Finally, earth and sand 55 are further backfilled around the foundation 4 to the level of the ground.
[0018]
According to the seismic isolation structure constructed in this way, vibration can be absorbed by the seismic isolation member 2 interposed between the steel pipe pile 1 and the foundation 4, and in the event of an earthquake, the building is It can be isolated from the part. Therefore, the base 4 can be prevented from being broken or distorted from the portion of the foundation 4 even though the building is okay, and the base can be isolated more effectively.
[0019]
Moreover, since this seismic isolation member 2 is interposed between the steel pipe pile 1 and the foundation 4, a building can be built on the foundation 4 in the same manner as in the conventional construction method. There is no need to build a building on the foundation 4 by a special construction method, and the construction cost can be prevented from increasing. Moreover, since the foundation 4 and the building can be integrated as in the conventional construction method, sufficient rigidity can be obtained.
[0020]
Furthermore, since the lid 3 is covered around the seismic isolation member 2 and a uniform gap D is ensured between the earth and sand 54 buried in the root cutting bottom 53 and the seismic isolation member 2, It can prevent that the seismic member 2 is pressed by the earth and sand 54, and the seismic isolation effect falls. Moreover, since the seismic isolation member 2 does not contact the earth and sand 54 directly, it can prevent that the seismic isolation member 2 deteriorates under the influence of the earth and sand 54. Further, a uniform gap D is secured between the seismic isolation member 2 and the lid 3 and the central axis from the steel pipe pile 1 to the lid 3 is not displaced. The foundation 4 provided can be in a stable state.
[0021]
In addition, in this Embodiment, although the ground 5 with the soft layer 51 was described, in the case of the ground 5 which does not have such a soft layer 51 and is comprised by the stable hard layer 52, Fig.4 (a). As shown, a short steel pipe pile 1 can be used. Further, as shown in FIG. 4B, a pedestal member 28 having a projecting portion 27 may be disposed on the root bottom 53, and the seismic isolation member 2 may be fitted to the projecting portion 27 with the recessed portion 21. .
[0022]
In the present embodiment, the seismic isolation member 2 having the recessed portion 21 is described. However, as shown in FIG. 5, the seismic isolation member 20 having a fixing flange 29 above and below the seismic isolation material 20 such as laminated rubber or a coil spring. The seismic member 2 may be used. Also in this case, as shown in the figure, the seismic isolation member 2 and the lid body are covered by covering the lid body 3 so that the fixing flange 26 is fitted into the rib 32 provided inside the lid surface 30 of the lid body 3. 3 can be made uniform.
[0023]
【The invention's effect】
As described above, according to the present invention, since the seismic isolation member is interposed between the groundwork and the foundation disposed at the bottom of the root and the seismic isolation member is not disposed on the foundation, the same construction method as the conventional construction method With this, it is possible to build a building on the foundation and prevent the construction cost from increasing.
[0024]
Moreover, since a building can be built on a foundation, sufficient rigidity in which the foundation and the building are integrated can be obtained.
[0025]
In addition, because the vibration is absorbed by the seismic isolation member interposed between the groundwork and the foundation located at the bottom of the root, the building can be isolated from the foundation, avoiding damage to the foundation. A safer seismic isolation structure can be obtained.
[0026]
Furthermore, since the lid that covers the seismic isolation member forms a gap around the seismic isolation member, it is possible to prevent the seismic isolation member from being pressed by the earth and sand. It can be fully demonstrated. Further, it is possible to prevent the seismic isolation member from coming into direct contact with the earth and sand and prevent the seismic isolation member from being deteriorated due to the influence of the earth and sand. Furthermore, since the gap between the seismic isolation member and the lid can be made uniform, the central axis from the ground industry to the lid will not shift, and the foundation placed on this lid will not be displaced. A stable state can be obtained.
[Brief description of the drawings]
FIGS. 1A to 1D are cross-sectional views showing an outline of the overall configuration of a seismic isolation foundation construction process.
FIGS. 2A to 2E are cross-sectional views showing other embodiments of the earthwork.
FIGS. 3A to 3D are cross-sectional views showing embodiments of the positioning state of the seismic isolation member and the lid.
4A and 4B are cross-sectional views showing another embodiment of the seismic isolation foundation.
FIG. 5 is a cross-sectional view showing another embodiment of the seismic isolation member.
[Explanation of symbols]
1 Steel pipe pile (Ground)
2 Seismic isolation member 3 Lid 30 Lid surface (top)
31 Reinforcing bar 32 Rib (positioning)
4 Foundation 5 Ground 53 Root cutting bottom 54 Earth and sand D Gap

Claims (1)

A lidded cylindrical lid body, in which a seismic isolation member is fixed on the groundwork arranged at the root cutting bottom, and a rib for positioning the seismic isolation member is projected on the inside of the lid surface on the seismic isolation member Cover the ribbed seismic isolation member in the rib, or provide a fitting part that fits unevenly into the seismic isolation member and the lid, and cover the lid with a lid with a cylindrical shape so as to match them. As a result , a uniform gap is formed between the seismic isolation member and the peripheral surface of the lid body, and the earth and sand are backfilled around the lid body up to the position of the top surface of the lid body, and the top surface of the lid body is projected. A seismic isolation foundation construction method, wherein a foundation is placed on the lid so that the reinforcing bars installed are buried.

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