JP2009007865A - Building structure - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To easily and economically execute processes after ground improvement when constructing a building structure using adhesion between the weight of ground improving bodies and the peripheral ground as pull-out resistance by integrating the foundation with the ground improving bodies. <P>SOLUTION: The building structure 1 has continuous-layer earthquake-proof walls 2 and is supported by the ground improving bodies 4. A foundation 3 immediately below one-side ends of the continuous-layer earthquake-proof walls 2 or foundations 3 immediately below both ends of the continuous-layer earthquake-proof walls 2 among the foundations 3 immediately below the continuous-layer earthquake-proof walls 2 are connected to the ground improving bodies 4 below the foundations by tensile-force transmitting steel members 5 buried in the ground improving bodies 4. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a building structure in which the foundation and the ground improvement body are integrated to use the weight of the ground improvement body and the adhesion to the surrounding ground as a pulling resistance.

  In building structures where direct foundations are adopted, columnar ground improvement bodies created on the surface ground below the foundation (for example, columnar shapes created by mixing and agitating surface soil ground excavating soil and cement milk and other solidifying agents. It is not only for the purpose of directly increasing the vertical bearing capacity of the foundation, but also as a pulling-out resistance force against the overturning moment that is generated when horizontal forces such as earthquakes and strong winds are applied to the building structure. Already known from US Pat.

  In this conventional example, as shown in FIGS. 1 to 6 in Patent Document 1, anchor materials (tensile force transmission steel materials) are buried in all columnar ground improvement bodies formed under the foundation, and the foundation and It is connected. As the anchor material (tensile force transmission steel material), shaped steel or deformed reinforcing bar can be used, but it is desirable to have a protrusion protruding toward the ground side at a position embedded in the ground improvement body. Patent Document 1.

  However, in the above-described conventional example, since the anchor material (tensile force transmission steel material) is embedded in all the columnar ground improvement bodies, there are the following problems.

  In other words, construction of this type of building structure is generally done by creating a columnar ground improvement body in the state of terrain, and using the anchor material (tensile force transmission steel) as the ground improvement body while the ground improvement body has not yet solidified. After the curing and curing of the ground improvement body, it is constructed in a state where the upper end side of the anchor material (tensile force transmission steel material) protruding above the ground improvement body is embedded above the ground improvement body, In the above-mentioned conventional example, in the state where the upper end side of the anchor material (tensile force transmission steel material) protrudes from all the columnar ground improvement bodies, the post-process is performed. (Foundation work), and because of the anchor material (tensile force transmission steel material), not only is the cumbersome work difficult, but it is also difficult to load heavy machinery into the site. , Rebar and formwork, support Of the loading of the material it becomes difficult, post-process becomes very troublesome.

  Moreover, if an anchor material (tensile force transmission steel material) is embedded in all columnar ground improvement bodies, the amount of steel material used is large, and there is a large possibility of excessive quality, which is also uneconomical.

JP 2000-291024

  The present invention has been made in view of the above-described problems, and the object of the present invention is to integrate the foundation and the ground improvement body, thereby reducing the weight of the ground improvement body and the adhesion to the surrounding ground. In constructing a building structure used as a pull-out resistance, the process after ground improvement is to be performed easily and economically.

The technical means taken by the present invention in order to achieve the above object are as follows. That is, the building structure according to the first aspect of the present invention is a building structure having a multi-layer seismic wall and supported by a ground improvement body, and a foundation directly below the multi-layer seismic wall and a ground beneath the foundation. The improved body is characterized by being connected by a tensile force transmission steel material embedded in the ground improved body.

  A building structure according to the invention described in claim 2 is the building structure according to claim 1, wherein, among the foundations immediately below the multi-layer earthquake-resistant wall, the foundation directly below one end or both ends of the multi-layer earthquake-resistant wall. Is connected to the ground improvement body under the foundation.

  According to this invention, the process after ground improvement can be performed easily and economically. That is, according to the first aspect of the present invention, the foundation directly below the multistory shear wall and the ground improvement body under the foundation are connected by the tensile force transmission steel material embedded in the ground improvement body. The tensile force transmission steel material that connects the two is concentrated and placed directly under the multistory earthquake-resistant wall. In particular, according to the invention described in claim 2, among the foundations directly below the multi-layer earthquake resistant wall, the foundation directly below one end or both ends of the multi-layer earthquake resistant wall is connected to the ground improvement body under the foundation. The tensile force transmission steel material connecting the foundation and the ground improvement body is concentrated and arranged immediately below one end portion or both end portions of the multi-layer earthquake resistant wall.

  Therefore, when the foundation is constructed in the state where the upper end side of the tensile force transmission steel material is embedded above the ground improvement body after the ground improvement, the upper end side of the tensile force transmission steel material is concentrated only in the vicinity of the planned construction position of the multistory shear wall. In particular, according to the invention described in claim 2, the upper end side of the tensile force transmission steel material projects in a concentrated manner only at the end portion of the planned construction position of the multistory earthquake resistant wall. Become.

  Therefore, in the foundation work after ground improvement, it is easy to pick out the ink. Moreover, when the heavy machinery is put on the site, the portion of the tensile force transmission steel material that protrudes above the ground does not become an obstacle. It is possible to run heavy machinery along the planned construction position, and it is possible to carry in materials such as reinforcing bars, formwork, and supporters for foundations by heavy machinery, so that the process after ground improvement can be performed easily Become.

  In addition, when a horizontal force due to an earthquake is applied, the tensile force transmission steel is concentrated at the end of the multistory shear wall where a pulling force is generated, thereby reducing the weight of the ground improvement body and the adhesion with the surrounding ground. Therefore, it is economical because the quantity of steel materials used and the amount of work for embedding steel materials in the ground improvement body are small, and the quality is not excessive.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 and FIG. 2 show a so-called one-sided core building structure 1 that is often used in office buildings and apartment houses with a large aspect ratio constructed on a small site. 2 is a multistory shear wall that constitutes the core, and 3 is a reinforced concrete foundation. 4 is a columnar ground improvement body formed under the foundation 3, and is formed by mixing and agitating a caking agent such as excavated soil of the surface ground and cement milk. The foundation 3 and the columnar ground improvement body 4 are connected and integrated by a tensile force transmission steel material 5, and the weight of the ground improvement body 4 and the adhesion force with the surrounding ground are used as a pulling resistance.

  The columnar ground improvement body 4 is constructed over the entire area under the foundation 3 (the entire bottom surface of the building structure 1), but the tensile force transmission steel 5 that connects the foundation 3 and the ground improvement body 4 under the foundation 3 is: It is arranged just under and near the multistory shear wall 2.

That is, among the columnar ground improvement body 4, the tensile force transmission steel material 5 in which the foundation 3 directly below the multistory shear wall 2 and the ground improvement body 4 under the foundation 3 are embedded in the ground improvement body 4 over the entire length thereof. It is connected with. Of the foundations 3 directly below the multi-layer earthquake-resistant wall 2, the foundations 3 immediately below both ends of the multi-layer earthquake-resistant wall 2 may be connected to the ground improvement body 4 by the tensile force transmission steel material 5, but in the illustrated embodiment, Only one end portion of the multi-layer earthquake resistant wall 2 corresponding to the outer end in the short side direction of the building structure 1 is connected to the ground improvement body 4 by the tensile force transmission steel material 5. This is because the column at the other end of the multistory shear wall 2 corresponding to the middle part in the short side direction of the building structure 1 has a large vertical load (the pulling force generated during the earthquake) transmitted from the beam or floor slab. While the large weight that is enough to cancel is acting, the vertical load borne by the column is small at one end of the multistory shear wall 2 (the outer edge in the short side direction in the building structure 1). This is because the pulling force sometimes generated is not offset.

  According to said structure, the process after ground improvement can be performed easily and economically. That is, among the foundations 3 directly below the multistory shear walls 2, the foundation 3 just below one end of the multistory shear wall 2 is connected to the ground improvement body 4 below the foundations 3 by the tensile force transmission steel 5, so that the tensile force The transmission steel material 5 is concentrated and arranged immediately below one end of the multi-layer earthquake resistant wall 2.

  Therefore, at the time of starting the foundation work after the ground improvement, the upper end side of the tensile force transmitting steel material 5 protrudes in a concentrated manner only at the end portion of the planned construction position of the multi-layer earthquake resistant wall 2. Therefore, when entering heavy machinery on the site, the portion of the tensile force transmission steel material 5 protruding above the ground does not become an obstacle, for example, it is possible to run heavy machinery along the planned construction position of the multistory earthquake resistant wall 2, Since it is possible to carry in materials such as reinforcing bars, formwork, and supporters for foundations by heavy machinery, the process after ground improvement can be performed easily.

  Further, when a horizontal force due to an earthquake is applied to the building structure 1, the tensile force transmitting steel 5 is concentrated on one end of the multistory shear wall 2 where a pulling force is generated, so the weight of the ground improvement body 4 and the surrounding ground It is economical because the amount of steel used and the amount of steel material embedded in the columnar ground improvement body 4 can be reduced and the quality does not become excessive.

  1 and 2, H-shaped steel is used as the tensile force transmission steel material 5. Further, instead of increasing the fixing length to the foundation 3, the stud 6 is welded to the portion embedded in the foundation 3 of the H-shaped steel (tensile force transmission steel 5), as shown in FIG. Adhesive strength to the foundation 3 is ensured by strength. Most of the H-shaped steel (tensile force transmission steel 5) (the portion corresponding to the length of the columnar ground improvement body 4) has a smooth outer surface and is not provided with studs or other protrusions. If the adhesion strength between the columnar ground improvement body 4 and the H-shaped steel (tensile force transmission steel material 5) is large, the length of the H-shaped steel (tensile force transmission steel material 5) embedded in the ground improvement body 4 can be shortened. However, when a pulling force is applied to the H-section steel (tensile force transmission steel 5), the ground improvement body 4 breaks up and down at a position where the H-section steel (tensile force transmission steel 5) is not inserted. In order to prevent this, it is desirable to embed the entire length of the ground improvement body 4.

  FIG. 4 shows another embodiment, in which the bearing plate 7 is welded to the upper end of the H-shaped steel (tensile force transmission steel 5) to ensure the adhesion strength to the foundation 3.

  Although not shown, as the tensile force transmission steel material 5, a deformed reinforcing bar or a threaded reinforcing bar can be used. In any case, it is desirable to process the hook and the collar on the upper end to increase the adhesion strength to the foundation 3.

  Moreover, in embodiment of FIG. 1, FIG. 2, although the foundation 3 just under the one end part of the multi-layer seismic wall 2 was connected with the ground improvement body 4 under the foundation 3 with the tensile force transmission steel material 5, it shows in FIG. In the building structure 1 having such a center core, the tensile force transmission steel materials 5 are concentratedly arranged at both ends of the multistory earthquake-resistant wall 2 constituting the center core. In addition, as shown in FIG. 6, the tensile force transmission steel 5 is concentrated on both ends of the multi-layer seismic wall 2 even in apartment buildings where one side is a corridor, the other side is a balcony, and the boundary wall is a multi-layer seismic wall. Will do.

As mentioned above, although embodiment of this invention was described based on drawing, this invention is not limited only to embodiment mentioned above, A various embodiment can be employ | adopted in the range which does not deviate from the summary of this invention. Of course. For example, the ground improvement body 4 may be a deep layer processing method or a shallow layer processing method. The shape of the ground improvement body 4 in the case of employing the deep mixing treatment method is not particularly limited, whether it is a column shape or a wall shape. When the shallow layer processing method is adopted, the entire bottom surface of the building may be improved or limited to a part of the bottom surface of the building.

It is a vertical side view which shows one Embodiment of this invention. It is a top view. It is a vertical side view of the principal part. It is a vertical side view of the principal part which shows other embodiment of this invention. It is a vertical side view which shows other embodiment of this invention. It is a vertical side view which shows other embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Building structure 2 Multistory earthquake-resistant wall 3 Foundation 4 Ground improvement body 5 Tensile force transmission steel

Claims (2)

  A building structure that has a multi-layer seismic wall and is supported by a ground improvement body, and has a foundation directly under the multi-layer seismic wall and a ground improvement body under the foundation embedded in the ground improvement body. Building structure characterized by being connected by.   2. The building structure according to claim 1, wherein a foundation directly below one end or both ends of the multi-layer earthquake-resistant wall is connected to a ground improvement body under the foundation among the foundation directly below the multi-layer earthquake-resistant wall.

Images