JPS64438Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a pile tip supporter used for driving foundation piles without noise and without fear of soil contamination by chemicals or the like.

[Conventional technology]

Conventionally, the cement milk method is one of the low-pollution construction methods that eliminates the noise, vibration, etc. that occur when driving concrete piles.

However, compared to the conventional pouring method, this cement milk construction method has drawbacks such as being too expensive and time consuming, concerns about support capacity during the construction process, and groundwater contamination.

As an alternative to this cement milk method,
Japanese Patent Publication No. 47-8408 and Japanese Patent Application Laid-Open No. 55-52428 disclose a construction method that attempts to reduce noise and vibration by pre-boring with an auger and then hitting the tip of the concrete pile inserted therein. Public notice,
It is disclosed in Japanese Patent Publication No. 57-10244, Japanese Utility Model Application Publication No. 57-71543, Japanese Patent Application Publication No. 58-58320, Japanese Patent Application Publication No. 58-58321, etc.

However, in this method of driving piles into the slum areas created by pre-boring, the bearing capacity of the driven piles is insufficient; , it is necessary to compensate for the lack of bearing capacity of each individual pile, resulting in large economic waste.

In addition, with the aim of reducing noise and increasing bearing capacity, a construction method in which the tip of the pile is hammered directly was published in Japanese Patent Laid-Open No. 54-132306.
However, the construction method disclosed in the same publication involves hammering the upper end of the transmission rod connected to the pile driving tip, so it does not actually reduce noise. The transmission rod itself must also be strong enough to withstand hammering. Furthermore, due to its structure, the tip of the pile is fixed with bolts, so there are various problems in realizing it, such as making it unsuitable for work in hard soil.

[The problem that the idea aims to solve]

The problem to be solved by the present invention is to provide a device for realizing a noiseless and pollution-free pile driving method.

[Means to solve the problem]

This invention is designed to be used as a pile tip supporter for driving piles by hammering the bottom plate of the pile tip supporter through the through hole of the pile while applying a load to the upper end of the pile. The above-mentioned problem has been solved by comprising a tube with a bottom plate that is longer than the hammering stroke, and by providing a plurality of locking protrusions on the inner wall of the tube to lock with the outer surface of the pile.

〔Example〕

FIG. 1 is a front sectional view showing a pile tip supporter 1 of the present invention in longitudinal section. FIG. 2 shows the pile tip supporter 1 in a plan view.

As shown in FIGS. 1 and 2, the pile tip supporter 1 of the present invention has an inner diameter slightly larger than the outer diameter of the pile 5, an inner diameter that allows the pile 5 to fit tightly, and A bottom plate 2 made of a steel plate or the like is fixed by welding or the like to the bottom of a tube body 3 having a length larger than the stroke of the tube 3 with enough strength to withstand hammering. Further, a plurality of locking protrusions 4 that lock with the outer wall of the driven pile 5 are provided on the inner wall of the tube 3 so as to protrude from the inner peripheral surface of the tube 3 . By this,
When the pipe body 3 is fitted to the tip of the pile 5, the pile 5
It has a structure that allows it to be locked to the pile tip supporter 1.

FIGS. 3 to 5 are diagrams showing the state of pile driving using the pile tip supporter 1 shown in FIGS. 1 and 2.

FIG. 3 is a cutaway sectional view showing a state in which the pile tip supporter 1 of the present invention is attached to the tip of a pile 5 and installed in a hole 8 in the soil. As shown in the figure, after the pile tip supporter 1 of the present invention is attached to the pile 5 and installed at the bottom of the hole 8 for foundation work, it is passed through the through hole 6 of the hollow pile 5.
The bottom plate 2 of the pile tip supporter 1 is hammered from above using a hammer 7.

FIG. 4 shows the state after the bottom plate 2 of the pile tip supporter 1 has been hammered a required number of times with the hammer 7. As shown in the figure, the pile end supporter 1, which was locked to the pile 5 by the locking protrusion 4, is removed from the bottom plate 2 of the supporter 1 by hammering the bottom plate 2 with the Monken hammer 7. It is forcibly driven into the soil with the tip of No. 5 separated. Then, a light hammering or a static load is applied to the upper end of the pile 5, and the pile slides and sinks within the supporter 1, almost following the penetration of the supporter 1 into the soil. By repeating this operation, the pile 5 is driven to a depth where the design strength is obtained.

FIG. 5 is a cutaway sectional view showing the state of the pile 5 after it has been driven.

The length of the pipe body 3 of the pile tip supporter 1 needs to be longer than the stroke of hammering by the hammer 7. The reason for this is that if the upper end edge of the pile tip supporter 1 is separated from the lower end of the pile 5, earth and sand will enter the gap, making it impossible to implement the above-mentioned construction method.

Therefore, the length of the pipe body 3 of the pile tip supporter 1 can be appropriately changed depending on the dimensions of the pile, the soil quality of the construction site, etc. The dimensions and thickness of the bottom plate 2 are such that they do not hinder insertion into the hole 8 and do not cause significant deformation due to hammering, and must be changed depending on the dimensions of the pile and the required proof load.

When carrying out the above construction method, the hammer 7 hammers the bottom plate 2 of the pile tip supporter 1 located at the bottom of the hole 8 through the through hole 6 of the pile 5, so almost no noise is generated.

After driving the pile, it can be easily determined whether the required proof load has been reached or not by easily calculating from the tonnage load at the time of hammering.

In the above embodiment, the bottom plate 2 of the pile tip supporter 1 is a simple plate-shaped body, but in order to prevent sideslip during hammering and to prevent the pile from escaping, the bottom plate 2 has a sideslip prevention plate. A protrusion can be provided.

FIGS. 6 to 9 show an example in which the sideslip prevention protrusion 9 is provided on the lower surface of the bottom plate 2 of the pile tip supporter 1.

FIG. 6 and FIG. 7 show an example in which the sideslip prevention protrusion 9 is formed by using a plurality of shaped steel pieces having an L-shaped cross section.

In the case of FIGS. 8 and 9, the sideslip prevention protrusion 9 protruding from the bottom surface of the bottom plate 2 is integrally formed in a radial cross shape with an apex in the center. Similarly, skidding can be prevented.

[Effect of idea]

The pile tip supporter of the present invention can provide the following effects.

(1) It has become possible to put into practical use a pile driving method in which the bottom plate of the pile end supporter is hammered through the through hole of the pile while applying a load to the top end of the pile, making it possible to drive piles without noise and soil contamination. Become.

(2) When driving piles, it is possible to know the bearing capacity of the piles and the number of required piles, which eliminates the need for unnecessary pile driving.

[Brief explanation of the drawing]

Figure 1 is a front cross-sectional view of the pile tip supporter of the present invention along the line shown in Figure 2, Figure 2 is a plan view of the pile tip supporter, and Figures 3 to 5 are a cross-sectional view of the pile tip supporter of the present invention. A conceptual diagram illustrating the driving method; FIGS. 6 and 7 are a front view and a bottom view of another example of a pile tip supporter having a sideslip prevention protrusion on the lower surface of the bottom plate; FIGS. 8 and 9 2 is a front view and a bottom view of another example. 1: Pile tip supporter, 2: Bottom plate, 3: Pipe body, 4:
Locking protrusion, 5: stake, 6: through hole, 7: monkey hammer, 8: hole, 9: skid prevention protrusion.

Claims (1)

[Scope of utility model registration request] While applying a load to the upper end of the pile 5, the through hole 6 of the pile 5 is
A pile tip supporter used in a pile driving method in which the bottom plate 2 of the pile tip supporter 1 is hammered through, and has an inner diameter slightly larger than the outer diameter of the pile 5 and a length larger than the hammering stroke. 1. A pile tip supporter comprising a tube 3 with two attachment points, and a plurality of locking protrusions that lock with the outer surface of a pile 5 on the inner wall of the tube 3.