JPH06101240A - Foundation, and constructing method therefor - Google Patents

Abstract

PURPOSE:To restrain vertical vibration acting on a slab-on-earth from propagating to surroundings by a method wherein the slab-on-earth is supported with the heads of foundation piles, and a vacant space is formed between the undersurface of the slab-on-earth and the surface of the ground. CONSTITUTION:Foundation piles 6 are driven into the ground 7 to which soil improvement is applied, and flat jacks 16 are mounted on heads of the piles 6 and damping units 10 are connected to the upper parts of the jacks 16. A sheet 17 is spread over laid gravels 11 and concrete 8 for slab-on-earth is placed over the sheet 17. After the concrete 8 is cured, the concrete 8 is lifted with the jacks 16 inflated, so that the concrete becomes afloat in a specified height H over the ground 7, and thereby a vacant space 9 is formed. In the case where downward impact acts on the concrete 8 because of pedestrian and vehicular traffic, the middle part of the concrete 8 makes vertical vibration because of existence of the vacant space, and vibration energy E1 and propagation energy E2 are partially consumed respectively by vibration of the concrete 8 and operation of the damping units 10. Thereby, vertical vibration occurring to the ground 7 can be restrained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention is applied to sports such as baseball, soccer, rugby, various athletics, motorcycles and cars.
Among the multi-purpose dome-shaped structures that are used for various purposes such as racing by bicycle, concerts of various music, various events, etc., basic technology such as the arena part surrounded by bleachers. Regarding the supported foundation and the construction method of it.

[0002]

2. Description of the Related Art In a conventional foundation of this type, foundation concrete piles support the foundation concrete in a state where the lower surface of the foundation concrete is in close contact with and supported by the ground.

[0003]

However, according to the above-mentioned conventional technique, a large number of people jump or bounce, or motorcycles or cars move violently like an arena of a dome-shaped structure. When the downward impact repeatedly acts on the soil concrete, the following problems occur. Since the lower surface of the soil concrete was supported by the ground in a state of being in close contact with the ground, the downward impact force acting on the soil concrete is almost directly transmitted to the ground. In that case, if the cycle in which the impact force acts matches the natural vibration cycle of the ground, the ground resonates and the vibration is propagated to the surroundings, and if the natural vibration cycle of the surrounding building matches the vibration cycle, The surrounding buildings resonate. In short, when earth-bottom concrete is repeatedly subjected to a downward impact force, there is a possibility that vertical vibration due to the impact may be propagated to surrounding buildings and violate the buildings unduly, resulting in vibration pollution. An object of the present invention is to provide a foundation that can reduce the propagation of vertical vibration to the surroundings due to the impact acting on the soil concrete, as the foundation having the earth concrete that often receives downward impact force repeatedly. In addition, the point is to provide a construction method capable of constructing the foundation in an advantageous manner.

[0004]

The feature of the foundation according to the present invention resides in that a void is formed between the lower surface of the soil concrete and the upper surface of the ground. Then, it is preferable to implement by providing a damping means for damping the transmission of vertical vibration from the soil concrete to the foundation pile.

A feature of the method of constructing a foundation according to the present invention is that a foundation pile is formed in the ground, a jack is attached to the head of the foundation pile, then concrete is poured into the soil, and then the jack is extended. The point is to raise the soil concrete so that its lower surface floats above the upper surface of the ground.

[0006]

[Function] According to the above foundation, since the void is formed between the soil concrete and the ground, the intermediate portion of the soil concrete extending between the foundation piles is freely displaced in the vertical direction without being disturbed by the ground. can do. As a result, when downward impact force is repeatedly applied to the soil concrete, the intermediate force of the soil concrete vibrates vertically due to the impact force, and the energy of the impact force exerted by the vertical vibration of the soil concrete can be consumed. it can. That is, it is possible to absorb the downward impact force by the soil concrete itself. In particular, when the damping means is provided as described above, it is possible to damp the vertical vibration transmitted from the soil concrete to the foundation pile, so that the vertical vibration is propagated from the soil concrete to the ground through the foundation pile. It is possible to further suppress the vertical vibration due to the impact force acting on the soil concrete from being propagated to the ground.

According to the above-mentioned construction method of the foundation, by simply extending the jack, the soil concrete on the ground is lifted, and a space is provided between the soil concrete and the ground for allowing vertical vibration of the soil concrete. Since it can be formed, the soil concrete can be created by the same operation as when the void is not formed, while forming the void. To be more specific, as means for creating soil concrete lifted from the ground, there are means for placing and forming the soil concrete in a state of being lifted from the ground using a formwork, and for forming the soil concrete using the ground as a formwork. After that, a method of excavating the ground to form a void is conceivable, but in the former case it requires laborious formwork construction, and in the latter case it is done in a very bad working environment such as under soil concrete. Ground excavation is required. On the other hand, according to the construction method of the present invention, such formwork construction and ground excavation are unnecessary.

[0008]

Therefore, according to the present invention, it is possible to suppress the transmission of the downward impact force acting on the soil concrete to the ground, and the vertical vibration of the soil caused by the downward impact force repeatedly acting on the soil concrete. It has become possible to provide a construction method capable of suppressing the vibration, providing a foundation useful for preventing vibration of surrounding buildings, and constructing a foundation useful for suppressing the vibration with good workability. In particular, according to claim 2, the vibration suppressing effect can be further enhanced.

[0009]

EXAMPLE As shown in FIG. 2, the dome-shaped structure has a structure in which the center arena part 1 and the seats 2 around the center are covered with a single dome-shaped roof 3, and the foundation is the arena. It is divided into a central foundation portion 4 for the portion 1 and a peripheral foundation portion 5 for the grandstand portion 2 and the dome-shaped roof 3. The central foundation part 4 includes a plurality of foundation piles 6 as shown in FIG.
Are installed in the ground 7, and the soil concrete 8 is placed on the heads of the foundation piles 6, and a damping means is formed in a state in which a void 9 having a set height H is formed between the lower surface of the soil concrete 8 and the upper surface of the ground 7. It is configured to be connected and supported via 10. That is, the soil concrete 8 is configured to be lifted from the ground 7. The foundation pile 6 is a friction pile and is a short pile having nodes 6a at a plurality of locations spaced apart in the longitudinal direction, and a connecting portion between the foundation pile 6 and the soil concrete 8 is configured to have a structure without footing. Has been done. In addition, the whole ground 7 is improved, and the peripheral portion 7a of the foundation pile 6 of the ground 7 is composed of gravel, and the gravel 11 is laid on the upper surface of the ground 7. The soil concrete 8 is a steel fiber reinforced concrete <Steel Fiber Rei> reinforced by mixing iron in a fibrous, linear or rod-like shape.
nforced Concrete, abbreviation is SFFC
Is. 〉. As shown in FIG. 4, the damping means 10 uses the viscous resistance and the frictional resistance to cause the soil concrete 8
Damper 12 and return spring 13 that provide resistance to the vertical movement of the
It is a damping unit consisting of and and is interposed between the foundation pile 6 and the soil concrete 8. The viewing seat section 2 includes an underground structure section 2A and an upper structure section 2B having a viewing section, and the peripheral foundation section 5 is a pile foundation. Of the piles 18 of the peripheral foundation portion 5, those on the outer peripheral side are bottom-expanded piles. 14 is a retaining wall made of soil cement. Next, the construction method of the central foundation portion 4 will be described based on the construction procedure. <1> As shown in (a) of FIG. 3, after foundation improvement, the foundation piles 6 are driven in and formed, and the flat jacks 16 are attached to the heads of the foundation piles 6 via the joints 15, and the flats Damping unit 1 on top of jack 16
0 is connected, and the gravel 11 is laid on the ground 7, and the soil concrete 8 and the ground 7 to be placed are placed on the upper surface of the gravel 11.
Spread the sheet 17 to separate the and. The flat jack 16 is well-known, and in brief, it is composed of two metal plates whose circumferences are closed. The flat jack 16 swells when the mortar is press-fitted between the metal plates, and the swelling occurs by hardening the press-fitting mortar. It is to maintain the state. <2> As shown in (b) of FIG. 3, the soil concrete 8 is placed on the sheet 17, and the upper surface thereof is located lower than the planned soil concrete upper surface level L by the vertical distance corresponding to the set height H of the void 9. To place. <3> After curing the soil concrete 8, the mortar is pressed into the flat jack 16 and the flat jack 16
The soil concrete 8 is inflated and stretched, and the soil concrete 8 is lifted so that the lower surface of the soil concrete 8 is lifted from the upper surface of the ground 7 by the set height H, and the hardening of the press-fitting mortar is awaited in that state (see FIG. 1).

According to the foundation of the above construction, the earth concrete 8 can be moved by the movement of a person or a car on the earth concrete 8.
If a downward impact force is applied to the soil concrete 8
Of the space between the joints with the foundation pile 6 is the void 9
It vibrates up and down due to the presence of. As a result, the energy E of the impact acting on the soil concrete 8 is divided into the vibration energy E1 that vibrates the soil concrete 8 and the propagation energy E2 that is propagated to the ground 7 through the foundation pile 6, and the vibration energy E1 is A part of the propagation energy E2 is consumed by the damping means 10 due to the vibration of the soil concrete 8. Therefore, the energy E0 of vibration transmitted from the soil concrete 8 to the ground 7
Is reduced by the amount e consumed by the vibration and damping means 10 of the soil concrete 8 and the vertical vibration of the ground 7 due to the downward impact force acting on the soil concrete 8 can be suppressed. In addition, the void 9 not only allows the vibration of the soil concrete 8 but also covers the entire lower surface of the soil concrete 8, so that a spring layer that guides the spring water in the lower portion of the soil concrete 8 to the drainage part is formed. It is also used. Further, according to the above method, it is possible to form the soil concrete 8 by using the ground 7 itself as a formwork, and, while forming the void 9, it is not necessary to excavate the ground 7. By the way, to give an example of the practical values of the arrangement interval of the foundation piles 6 and the thickness of the soil concrete 8, each is 3000 to 5000 m.
m, 250 to 350 mm.

[Other Embodiment] In the above embodiment, the damping means 1 is used.
However, the present invention may be implemented without providing the damping means 10. In the above-described embodiment, the damping means 10 is provided so that the damping characteristic can be changed and adjusted by remote control. In the above-described embodiment, the foundation pile 6 was used and a large number of short friction piles were used, but a support pile may be used as the foundation pile 6. Moreover, in the said Example, the arrangement | positioning space | interval of the foundation pile 6 was made comparatively small, and the soil concrete 8
Although the thickness of the foundation pile 6 is reduced, if the cushioning performance is improved by increasing the intermediate portion of the soil concrete 8 that vertically vibrates due to the impact force, the arrangement interval of the foundation piles 6 is increased. In short, the arrangement interval of the foundation piles 6, the thickness of the soil concrete 8, the type and length of the foundation piles 6 to be used, etc. are appropriately selected from the cushioning surface and the strength surface. In the above embodiment, a vibration damping device that suppresses vibration of the intermediate portion of the soil concrete 8 is provided and implemented. In this case, the soil concrete 8 is configured to easily vibrate up and down, and the impact force is converted into the vertical vibration of the soil concrete 8 to efficiently perform buffering, while the impact concrete vertically vibrates vertically. Can be absorbed by the vibration control device to suppress vertical vibration of the soil concrete 8. In the above embodiments, the foundation of the dome-shaped structure is shown, but the present invention can be applied to the foundation of various structures.

It should be noted that although reference numerals are given in the claims for convenience of comparison with the drawings, the present invention is not limited to the configurations of the accompanying drawings by the entry.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a main part

FIG. 2 is a vertical sectional view of a dome-shaped structure.

FIG. 3 is a vertical cross-sectional view of a main part showing a construction procedure.

FIG. 4 is an enlarged vertical sectional view of a main part.

[Explanation of symbols]

 6 Foundation pile 8 Dirt concrete 7 Ground 9 Void 10 Damping means 16 Jack

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hisato Okude 4-1-1 Hommachi, Chuo-ku, Osaka City, Osaka Prefecture Takenaka Corporation Osaka Head Office

Claims (3)

[Claims] 1. A foundation in which soil concrete (8) is supported on the head of a foundation pile (6), and a gap () is formed between the lower surface of the soil concrete (8) and the upper surface of the ground (7). 9) The foundation that has formed. 2. Damping means (10) for damping the transfer of vertical vibrations from said soil concrete (8) to foundation piles (6).
The foundation according to claim 1, wherein the foundation is provided. 3. A foundation pile (6) is formed in the ground (7),
After mounting the jack (16) on the head of the foundation pile (6),
Soil concrete (8) is cast and formed, and then the jack (16) is extended to make the soil concrete (8).
The method of constructing a foundation in which the lower surface of the foundation is lifted up from the upper surface of the ground (7).