JP2786358B2 - Damping pile foundation structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a damping pile foundation structure.

[0002]

2. Description of the Related Art FIG. 8 shows a conventional pile foundation structure.
An upper structure d is constructed on a foundation b and a foundation beam c supported by a pile a such as a pile, a steel plate, a cast-in-place pile, and the pile a has a bending strength and a shear strength so as to resist horizontal force such as an earthquake or wind. Is configured. In the figure, e is the supporting ground, and f is the ground surface.

[0003]

In the above-mentioned conventional structure, the pile is resistant to a large earthquake by the strength of the pile. When the resonance phenomenon occurs due to the coupling of the superstructure and the pile,
The amplitude of the superstructure may increase, and the superstructure and / or the pile may be damaged.

The present invention has been proposed in view of the above-mentioned problems of the prior art. The object of the present invention is to provide a structure including piles that has a damping effect due to vibration damping when a horizontal force is applied. The point is to provide a damping pile foundation structure to be dripped.

[0005]

In order to achieve the above-mentioned object, the present invention relates to a vibration-damping pile foundation structure having an input horizontal force.
Steel sheet which yields before piles or superstructures yield
Or perforated steel plate between the upper piles and the lower surface of the superstructure.
And it is configured by installing me.

[0006]

Since the present invention is configured as described above,
When a horizontal force of an earthquake or a wind acts on the coupled structure including the pile and the upper structure, the ultra-mild steel is installed between the upper piles and over a lower surface of the upper structure before the pile or the upper structure yields. The plate or the perforated steel plate yields and energy is absorbed, and the structure has a vibration damping effect due to vibration damping.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to an embodiment shown in FIGS. 1 is a steel pile composed of a PC pile, a steel pipe pile, an H steel pile, etc., a pile composed of a cast-in-place concrete pile, etc., 2 is a foundation, 3 is a foundation beam, and 4 is a superstructure.
The extremely mild steel plate 5 is installed over the upper part of the pile extending slightly below the point where the bending moment in the ground is maximized from the uppermost end of the pile, and over the lower surface of the upper structure 4. In the figure, reference numeral 6 denotes a support layer.

[0008] Since the illustrated embodiment is configured as described above, the coupled structure composed of the pile 1 and the upper structure 4 has:
Pile 1 or superstructure 4 when horizontal force of earthquake or wind acts
Before yielding, the extremely mild steel plate 5 yields and energy is absorbed, so that the coupled structure has a vibration damping effect due to vibration damping. At the same time, the ground near the surface of the pile 1 receives a large moment and a shearing force and is greatly deformed, and is likely to be bent or sheared. Is prevented.

[0009] The mild steel plate 5 is the earthquake-resistant wall 7 of the upper structure 4.
It is effective to install it on the part of the pile 1 that corresponds to the lower part of. FIG.
Shows an embodiment of the application of the location hitting concrete pile as the pile 1, and excisional lower pile rebar cage 10 comprising more the lower pile main reinforcements 10 a and hoop 10 b to the drilling unit 9, then the upper pile main reinforcement the 8 a and hoop 8 b become more upper pile reinforcement cage 8 and excisional by lap joint on the lower pile rebar cage 10 to pouring the pile concrete. Next, the foundation 2 and the foundation beam 3 are constructed, and the extremely mild steel plate 5 is anchored to the upper reinforced basket 8 and the foundation beam 3 of the cast-in-place concrete pile via anchoring bars 11 and 12, respectively. In the figure, reference numeral 5a denotes a reinforcing rib of an extremely mild steel plate.

FIG. 5 shows an embodiment of the extremely mild steel plate 5, in which ribs 5a are provided on both front and back surfaces of an I-shaped plate-shaped piece. FIG. 6 shows a perforated steel plate 5 'made of a normal steel plate with a slit 13 used as a damping element instead of the extremely mild steel plate.
Denotes a perforated steel plate 5 ″ made of ordinary steel plate having ribs 14 and through holes 15.

[0011]

According to the present invention, as described above, the upper part of the pile, which is slightly lower than the point where the bending moment in the ground becomes maximum from the uppermost end of the pile, and the lower surface of the upper structure, By installing an ultra-soft steel plate or a perforated steel plate that constitutes the damping element, the steel plate bends and shears before the pile or the superstructure yields, and bears the stress, thereby bending and shearing the pile. And the plastic hinge of the pile is hardly formed.

[0012] Further, the ultra-soft steel sheet or the perforated steel sheet constituting the damping element draws a hysteresis loop to absorb energy,
The vibration displacement of the superstructure is suppressed by increasing the damping of the pile. As described above, according to the present invention, a structure can be damped without providing a special damping device, and a large damping effect can be obtained with a simple configuration without requiring maintenance.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing one embodiment of a damping pile foundation structure according to the present invention.

FIG. 2 is a cross-sectional plan view of FIG.

FIG. 3 is a partially enlarged longitudinal sectional view of FIG. 1;

FIG. 4 is a view taken along the arrow in FIG. 3;

FIGS. 5A and 5B are a front view and a side view as well as a rear view of an extremely mild steel plate.

FIGS. 6 (a) and (b) are a front view and a longitudinal side view of a perforated steel sheet.

FIGS. 7A and 7B are a front view and a side view of a perforated steel sheet.

FIG. 8 is a longitudinal sectional view showing a conventional pile foundation structure.

[Explanation of symbols]

 Reference Signs List 1 pile 2 foundation 3 foundation beam 4 superstructure 5 mild steel plate 5 'perforated steel plate 5 "perforated steel plate 6 support layer 7 earthquake-resistant wall

Claims (1)

(57) [Claims] 1. A pile or a superstructure by an input horizontal force.
Steel sheet or perforated steel sheet that yields before
A foundation structure for damping piles, which is installed between piles and the lower surface of an upper structure.