JP2007039938A - Foundation structure of building - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a foundation structure of a building capable of exhibiting the vibration damping effect while reducing rotational restriction (a pile head fixing degree) by reducing joining of a foundation and a pile. <P>SOLUTION: This foundation structure 1 is characterized in that the pile 5 having a pile head part 8 embedded in the foundation 6 of the building is joined via a shock absorbing material 7, and the shock absorbing material 7 is composed of a vertical part 10 covering the embedding part outer periphery 9 of the pile embedded in the foundation 6 and a horizontal part 13 having the same diameter as a pile upper surface 11 and opening a hole 12 in a central part, and the pile 5 and the foundation 6 contact by a small cross-sectional part 14 of the hole 12. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a basic structure of a building.

Conventionally, even if it is a cast-in-place concrete pile or a ready-made pile, since the foundation and the pile are rigidly joined, as shown in FIG. 19 was established. However, when the pile head 18 is rigidly joined to the foundation 19, when a horizontal force such as an earthquake is applied, the stress generated in the pile head 18, the foundation beam 21, and the like increases, so the reinforcement of the members must be excessive. There was a problem that had to be done. In order to solve such a problem, as shown in FIG. 6, a structure in which a taper 23 is attached to the pile head 22 or a small cross-sectional member 24 is sandwiched is proposed. In addition, as a basic structure of other buildings, for example, the invention of JP-A-2001-32296 is known.
JP 2001-32296 A

  However, the tapered structure described above has a problem that the horizontal deformation increases more than the pile head fixing, so that the movement and inclination of the building become large and residual deformation remains after the earthquake. Moreover, since the structure which pinched | interposed the small cross-section member reduced only rotation restraint, the energy absorption performance of the pile head was small, and the shaking of the superstructure might become large at the time of an earthquake.

  The present invention has been made in view of these problems, and its purpose is to reduce the rotation restraint by reducing the bonding between the foundation and the pile, and to provide a foundation structure of the building that can exhibit a damping effect. Is to provide.

  The foundation structure of the building for solving the above problems is that the pile head is buried in the foundation of the building and the pile is joined via a cushioning material, and the cushioning material is attached to the outer periphery of the buried part of the pile buried in the foundation. It is comprised from the vertical part to cover and the horizontal part which is the same diameter as the pile upper surface, and the hole was opened in the center part, and the pile and the foundation have contact | connected by the small cross-sectional part of the said hole. It also includes the fact that the shaft reinforcing bar that extends between the pile and the foundation is arranged in the small cross section of the hole.

  Since the foundation and the pile are in contact with each other with a small cross section, these constructions can be easily performed. In addition, it is possible to adjust the pile head fixing degree that reduces the rotation restraint by reducing the joint between the foundation and the pile by the small cross section, and the damping effect can be adjusted by the material and size of the cushioning material The degree of freedom in design can be increased. Moreover, because the fluctuation of pile head fixing degree is small regardless of horizontal deformation due to horizontal force, economic design is possible and the seismic performance is stable. In addition, the resilience performance of the cushioning material increases the return-to-origin performance after the earthquake and reduces residual deformation. It also has a vibration control effect in the horizontal and vertical directions, reducing not only the phenomenon of horizontal deformation of the building, but also the horizontal and vertical vibration of the building.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of a building foundation structure according to the present invention will be described with reference to the drawings. FIG. 1 shows the basic structure of a building according to the first embodiment (hereinafter referred to as a basic structure). The basic structure 1 of the present invention is a pin joint fixing degree as shown in FIG. It is located between the base structure 2 and the rigidly connected base structure 3. This pile head fixing degree refers to the degree to which the joint between the foundation and the pile is reduced to reduce the rotation constraint.

  This foundation structure 1 is constituted by a pile 5 placed on the ground 4 being joined to a concrete foundation 6 via a buffer material 7. This pile 5 is a ready-made pile made of concrete, a cast-in-place concrete pile or a cast-in-place steel pipe concrete pile. 7 is composed of a vertical portion 10 that covers the embedded portion outer periphery 9 embedded in the concrete foundation 6, and a horizontal portion 13 that has the same diameter as the pile that covers the pile upper surface 11 and has a hole 12 opened in the center. 12 is in contact with the concrete foundation 6 only by the small cross section 14 formed in 12. The buffer material 7 is composed of a viscoelastic material, a polymer material, a high-damping rubber, rubber, asphalt pitch, lead, or the like having elastic resilience performance or energy absorption performance such as history damping and viscosity damping.

  Thus, since the outer edge portion of the pile upper surface 11 and the buried portion outer periphery 9 of the pile head are insulated from the concrete foundation 6 by the cushioning material 7 and are in contact with each other only by the small cross section 14, the pile head 8 is easily rotated. As a result, the pile head fixing degree decreases. Therefore, as shown in FIG. 2, when the pile head 8 is rotationally deformed, the cushioning material 7 of the vertical portion 10 and the horizontal portion 13 is also deformed, so that the pile 5 tries to return to the origin by reducing the residual deformation by the elastic repulsive force. At the same time, the shaking of the building is reduced by the energy absorbing power of the cushioning material 7, and the impact force is also absorbed to improve the seismic performance of the pile 5 and the building. Further, even when a pulling force is applied as well as a horizontal force, the vertical portion 10 of the cushioning material 7 is deformed and a damping effect is exhibited. On the other hand, the axial force and bending moment are supported by the small cross section 14, and the shearing force is engaged by friction and unevenness of the concrete surface, and is engaged with the foundation (where the pile head is slightly embedded in the foundation). To pay.

  FIG. 4 shows a basic structure 15 according to the second embodiment. This foundation structure 15 is the same as the foundation structure 1 of the first embodiment except that a shaft reinforcing bar 16 extending between the pile 5 and the concrete foundation 6 is arranged on the small cross-sectional portion 14 of the hole 12. It is a configuration. The shaft reinforcing bar 16 is arranged when the pile 5 is expected to have a pulling resistance or when the shearing force is excessive, and when the pulling resistance is increased or the shearing force is excessive, the reinforcing bar is concentrated. To do.

  The cushioning material 17 in the foundation structure 15 has the same configuration as the cushioning material 7 in the foundation structure 1 of the first embodiment, and has the same effect.

It is a basic structure of a 1st embodiment, (1) is a sectional view and (2) is an AA line section of (1). It is sectional drawing which shows the horizontal deformation | transformation of the basic structure of 1st Embodiment. It is the figure which showed the pile head fixed degree. It is the basic structure of 2nd Embodiment, (1) is sectional drawing, (2) is the BB sectional view of (1). It is a conventional foundation structure, (1) is a sectional view of the foundation structure of a cast-in-place concrete pile, and (2) is a sectional view of the foundation structure of a ready-made pile. (1) And (2) is sectional drawing of the conventional basic structure.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1,15 Foundation structure 2 Foundation structure of pin joining 3 Foundation structure of rigid joining 4 Ground 5 Pile 6, 19 Concrete foundation 7, 17 Buffer material 8, 18, 22 Pile head 9 Peripheral part outer periphery 10 Vertical part 11 Pile upper surface 12 Hole 13 Horizontal part 14 Small cross section 16 Axial reinforcing bar 20 Main bar 21 Foundation beam 23 Taper 24 Small cross section member

Claims (2)

  A pile with a pile head embedded in the foundation of the building is joined via a cushioning material, and the cushioning material has a vertical portion covering the outer periphery of the buried portion of the pile buried in the foundation, the same diameter as the top surface of the pile, and a central portion A building foundation structure characterized in that the pile and the foundation are in contact with each other by a small cross-sectional portion of the hole.   The foundation structure of a building according to claim 1, wherein a shaft reinforcing bar extending between the pile and the foundation is arranged in a small cross section of the hole.

Images