JPS62202115A - Pile with blade - Google Patents

Abstract

PURPOSE:To enhance resisting powers against horizontal forces by providing horizontal blades to the head of a pile. CONSTITUTION:A cylinder 4 whose periphery is provided with projected horizontal blades 3 is fitted on the head 1 of a pile. The reaction of the pile in relation to the ground can be increased by the blades 3 when horizontal forces by earthquake, etc., act on the pile. The resisting power of the pile foundation structure canthus be increased.

Description

[Detailed description of the invention] (Industrial application field) The present invention relates to piles that support buildings.

(Prior Art) and (Problems to be Solved by the Invention) Piles that support buildings have traditionally existed in local industry, but with the enforcement of the New Earthquake-Resistant Design Law, they are now used in structures equivalent to superstructures. It was treated as part of the

As a result, when designing piles, it became necessary to consider not only vertical forces but also their resistance to horizontal forces such as seismic forces.

The bearing capacity of a pile, which is related to bearing capacity and deformation, is determined by the mutual bearing capacity of the pile body and the ground, but conventionally no measures have been taken to actively introduce ground reaction forces.

Moreover, the horizontal force resistance of the pile is higher than the vertical resistance of the same diameter, and the pile diameter has been forced to increase.

(Means for Solving the Problems) The present invention was proposed to solve the above problems, and consists of horizontal blades protruding from the outer periphery of the pile head to prevent horizontal forces such as earthquake forces. The present invention relates to a winged pile characterized in that the winged pile is configured to increase the reaction force received from the ground by the horizontal wings when acting.

(Function) Buildings with piles that are subjected to horizontal forces such as seismic forces will experience horizontal displacement, and the horizontal force (easher) that acts on the foundation is mainly borne by the stiffness of the piles and the ground reaction force. However, according to the present invention, the horizontal wings provided on the pile head increase the reaction force received from the ground, thereby increasing the ability to resist horizontal forces such as earthquakes.

(Effects of the Invention) As described above, according to the present invention, the horizontal resistance of the pile can be increased without increasing the pile diameter by the horizontal wings of the pile head, and a structurally rational and economical pile can be constructed. be.

(Example) The present invention will be described below with reference to the illustrated embodiments.

Building (Bl) with piles (A) subjected to horizontal force such as earthquake force
causes horizontal displacement as shown in Figure 6, and the horizontal force (base shear) H acting on the foundation is mainly borne by the stiffness of the pile (A) and the ground reaction force R, and this ground reaction acting on the pile The force R schematically has a semicircular shape as shown in FIG.

Therefore, in the case of a large earthquake, the horizontal resistance of piles is often expected to be due to the ground reaction force. Figures 1 and 2 show the present invention, which focuses on such ground reaction force and increases the horizontal resistance. Examples of piles are shown, and (1) is a pile frame that supports a building (2), with horizontal wings (3) protruding from the outer periphery of the pile head.

The horizontal blade (3) is provided to protrude from the outer peripheral surface of the cylindrical body (4), and by fitting the cylindrical body (4) to the pile head, the horizontal blade (3) and the pile body (1) are connected. The joint is in a bottle state,
To prevent a bending moment generated at a joint between a horizontal wing (3) and a pile body (1) from adversely affecting the pile body (1). Further, it is preferable that the cylindrical body (4) and the horizontal blade (3) are made of a tough material such as steel fiber concrete and manufactured in a factory.

Since the illustrated embodiment is configured as described above, when a horizontal force such as an earthquake force acts, the reaction force received from the ground of the pile by the horizontal blade (3) increases, and the earthquake force on the pile foundation structure increases. The ability to resist horizontal forces such as (See Figures 3 and 4) Under normal ground conditions, the ground reaction force that acts on the pile is expected to occur at a shallow depth from the ground surface, so the horizontal wing ( 3) is installed at the head of the pile.

In the embodiment shown in Fig. 1, the horizontal blade (3) is a pile frame (
1), one pair is arranged along the diameter direction, but it is also effective to arrange them in a cross shape as shown in Fig. 2 so as to resist seismic force from unspecified directions.

Note that (5) in the figure indicates the underground beam direction.

In addition, if the horizontal displacement of the pile head becomes large during an earthquake, the ground (C1) between the front and rear row piles (C1), which is indicated by diagonal lines in Figure 5, will no longer exert a reaction force on the pile (G). is expected.

In such a case, the pile foundation structure will be in a state like a cylindrical foundation surrounding the ground (C1), and the pile foundation structure will be in a state like a cylindrical foundation surrounding the ground (C1),
A shearing resistance is exerted between C) and the ground (D) below it, and this shearing resistance increases the horizontal resistance of the pile foundation.

Although the present invention has been described above with reference to embodiments, the present invention is, of course, not limited to such embodiments, and can be modified in various ways without departing from the spirit of the present invention. .

[Brief explanation of drawings]

FIG. 1 is an exploded slope view showing one embodiment of the winged pile according to the present invention, FIG. 2 is a plan view showing another embodiment of the winged pile according to the present invention, and FIGS. 3 and 4 are 5 is a vertical cross-sectional view of a building with piles according to the present invention, and FIGS. 6 and 7 are respectively when a horizontal force acts on a building with piles. FIG. 2 is an explanatory diagram showing the displacement of the foundation structure and the distribution of ground reaction force against the piles. (1)...Pile frame (3)...Horizontal wing agent Patent attorney Shige Okamoto 2 other people

Claims (1)

[Claims] It is characterized by having horizontal wings protruding from the outer periphery of the pile head, and configured to increase the reaction force that the pile receives from the ground due to the horizontal wings when a horizontal force such as an earthquake force acts. Winged stake.