JP6383547B2 - Building basic structure - Google Patents

Description

  The present invention relates to a foundation structure of a building having a soil concrete floor slab.

  Pile foundation is one of the foundations for building buildings on the ground. In the pile foundation, in the construction of the building on the soft ground, the building is supported by the pile provided in the soft ground. For example, Patent Literature 1 discloses a liquefaction countermeasure support pile in which a porous water permeable layer is formed on the outer periphery of a pile body.

  However, in a building supported by such piles, if the bottom floor of this building is a concrete floor slab supported directly by the ground, the floor will sink when the ground liquefies due to an earthquake. I am worried about it.

JP-A-9-316874

  This invention considers the fact concerned, and makes it a subject to control subsidence of a soil concrete floor slab provided in a building supported by a support structure built in the ground.

  The invention according to the first aspect includes a first support structure that is constructed in the ground and supports a building, and a columnar second support that is constructed in the ground and supports the soil concrete floor slab provided on the ground. A basic structure of a building having a structure.

  In the invention of the first aspect, by supporting the soil concrete floor slab with the second support structure, the soil concrete floor slab provided on the ground can be prevented from sinking due to liquefaction of the ground or the like. .

  The invention of the second aspect is the foundation structure of the building of the first aspect, wherein the first support structure and the second support structure are ground improvement bodies.

  In the second aspect of the invention, since the first support structure and the second support structure are the same ground improvement body, if the second support structure is constructed at the time of construction of the first support structure, the second support structure is efficiently produced. Can be constructed.

  According to a third aspect of the present invention, in the foundation structure of the building of the first or second aspect, the second support structure is evenly arranged with respect to the soil concrete floor slab.

  In the invention of the third aspect, by disposing the second support structure evenly with respect to the soil concrete floor slab, it is possible to suppress the uneven settlement of the soil concrete floor slab due to liquefaction of the ground.

  Since this invention set it as the said structure, the settlement of the soil concrete floor slab provided in the building supported by the support structure built in the ground can be suppressed.

It is an elevation view which shows the building which concerns on embodiment of this invention. It is a front view which shows the foundation structure of the building which concerns on embodiment of this invention. It is a top view which shows arrangement | positioning of the ground improvement body which concerns on embodiment of this invention.

  Embodiments of the present invention will be described with reference to the drawings. First, the foundation structure of the building which concerns on embodiment of this invention is demonstrated.

  In the elevation view of FIG. 1, a building foundation 10 of the present embodiment is shown. The building foundation structure 10 includes a columnar ground improvement body 12 as a first support structure and a columnar ground improvement body 14 as a second support structure. The ground improvement bodies 12 and 14 are constructed in the soft ground 16 as the ground, and the lower end reaches a support layer (not shown) formed below the soft ground 16.

  As shown in the front views of FIG. 1 and FIG. 2, a frame column 20 of a steel structure building 18 is built on the ground improvement body 12 via a footing 24. Supports the building 18. The floor of the first floor of the building 18 is constituted by a soil concrete floor slab 22 provided on the soft ground 16 so as to be directly supported by the soft ground 16, and the soil concrete floor slab 22 is improved in the ground. It is supported by the bodies 12 and 14 via the footings 24 and 26.

  As shown in the plan views of FIG. 1 and FIG. 3, the ground improvement body 14 is arranged substantially evenly in plan view with respect to the lower surface of the soil concrete floor slab 22. Here, the ground improvement body 14 is arranged substantially evenly in plan view with respect to the lower surface of the soil concrete floor slab 22. The load of the soil concrete floor slab 22 borne by each ground improvement body 14 is substantially equal. It means that the ground improvement bodies 14 are scattered and arranged. For example, as in areas A1, A2, and A3 shown in FIG. 3, the ground improvement bodies 14 are arranged so as to be scattered so that the areas of the lower surfaces of the soil concrete floor slabs 22 assigned to the various ground improvement bodies 14 are substantially equal. To do. In addition, the ground improvement body 14 is not provided in the position where the ground improvement body 12 is arrange | positioned by making this ground improvement body 12 also play the role which supports the soil concrete floor slab 22. FIG.

  Next, operations and effects of the building foundation structure according to the embodiment of the present invention will be described.

  In the basic structure of the building of this embodiment, as shown in FIG. 2, the soil concrete floor slab 22 provided on the soft ground 16 is supported by the ground improvement body 14 so that the soil concrete floor slab 22 is soft ground. 16 can be prevented from sinking due to liquefaction.

  Moreover, in order to suppress subsidence of the soil concrete floor slab 22, it is not necessary to make the soil concrete floor slab 22 thick. Further, the floor portion on the first floor of the building 18 does not have to be a structural floor slab that requires foundation beams. That is, it is possible to reduce the time and labor required for the construction of the first floor of the building 18.

  Furthermore, in the foundation structure 10 of the building of this embodiment, the long-term load acting from the soil concrete floor slab 22 is supported by the soft ground 16 that is not liquefied (without expecting support by the ground improvement body 14). If the ground improvement body 14 is designed to have a supporting force that does not allow the soil concrete floor slab 22 to sink when the ground 16 is liquefied, the burden on the soil concrete floor slab 22 and the ground improvement body 14 is reduced. (For example, the thickness of the soil concrete floor slab 22 can be reduced, the bar arrangement can be reduced, or the cross section of the ground improvement body 14 can be reduced), thereby reducing the cost of the foundation structure 10 of the building. Can be planned.

  Moreover, in the foundation structure 10 of the building of this embodiment, the 1st support structure which supports the building 18, and the 2nd support structure which supports the soil concrete floor slab 22 are the same ground improvement bodies (ground improvement bodies 12 and 14). ), And can be constructed by the same construction method, so if the ground improvement body 14 is constructed at the time of the construction of the ground improvement body 12, a thick soil concrete floor slab or a structural floor slab requiring a foundation beam is constructed. As a result, the building foundation 10 can be constructed efficiently in a short period of time.

  Furthermore, in the foundation structure 10 of the building according to the present embodiment, the ground improvement body 14 is arranged substantially evenly in plan view with respect to the lower surface of the soil concrete floor slab 22, so that the soil between the soft ground 16 due to liquefaction and the like Uneven settlement of the concrete floor slab 22 can be suppressed.

  The embodiment of the present invention has been described above.

  In the present embodiment, an example is shown in which the lower ends of the ground improvement bodies 12 and 14 as the first and second support structures reach the support layer, but the first support structure has the soft ground 16. If the building 18 can be supported when liquefied, and the second support structure can support the soil concrete floor slab 22 when the soft ground 16 is liquefied, the first and second support structures. The bottom end may or may not reach the support layer.

  Moreover, in this embodiment, although the example which made the 1st and 2nd support structure the ground improvement bodies 12 and 14 was shown, when the soft ground 16 liquefies, the 1st support structure is the building 18 being liquefied. Any support structure may be used as long as it can support the second support structure as long as it can support the soil concrete floor slab 22 when the soft ground 16 is liquefied. For example, the first and second support structures may be piles. In this case, various piles, such as a reinforced concrete pile, a prestressed high-strength concrete pile, a steel pipe pile, can be used for a pile.

  Furthermore, in this embodiment, although the ground improvement body 14 as a 2nd support structure was shown substantially equally arrange | positioned by planar view with respect to the lower surface of the soil concrete floor slab 22, 2nd support structure May not necessarily be arranged substantially evenly with respect to the lower surface of the soil concrete floor slab 22. When the second support structure is not arranged substantially evenly with respect to the lower surface of the interstitial concrete floor slab 22, setting of the reinforcement of the interstitial concrete floor slab 22, the strength of the second support structure, the size of the cross section, etc. Thus, the second support structure can prevent the soil concrete floor slab 22 from sinking or unevenly sinking due to liquefaction of the soft ground 16 or the like.

  Moreover, the building 18 shown in this embodiment may be a building having an underground floor. In this case, the soil concrete floor slab that constitutes the floor of the lowest floor of the basement floor of the building is supported by the ground improvement body 14.

  Furthermore, in the present embodiment, an example in which the building 18 is a steel structure is shown. However, the building 18 is a reinforced concrete structure, a steel structure, a steel reinforced concrete structure, a CFT structure (Concrete-Filled Steel Tube: filled steel tube concrete structure). ), And buildings of various structures and scales such as a mixed structure thereof.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to such embodiment at all, Of course, in the range which does not deviate from the summary of this invention, it can implement in a various aspect.

10 Building basic structure 12 Ground improvement body (first support structure)
14 Ground improvement body (second support structure)
16 Soft ground (ground)
18 Building 22 Soil concrete floor slab

Claims (3)

A first support structure that is built in the ground and supports the building pillars of the building;
Built in said ground, said earth floor concrete floor slabs and the support provided on the ground, a second support structure of the columnar lower end to reach the support layer formed below the ground,
The basic structure of the building.   The building foundation structure according to claim 1, wherein the first support structure and the second support structure are ground improvement bodies.   The foundation structure of a building according to claim 1 or 2, wherein the second support structure is evenly arranged with respect to the soil concrete floor slab.

Images