JPS6023522A - Construction work of concrete pile - Google Patents

Abstract

PURPOSE:To permit the settlement of a concrete pile without causing any damage to the pile by a method in which the pile is settle into the sludged portion of an excavated pit while applying a downward load through a buffer to a vibrator set on the head of the pile and also while applying a vertical vibration to the pile. CONSTITUTION:The ground 1 is excavated by an earth auger 2, and the soil is made sludgy with ground water, etc., by stirring it by a non-spiral blade 3. When the tip of the auger 2 reaches the bearing subsoil, cement milk is jetted from the tip of the auger 2 to form the mixed lump 5 of the cement milk and the sludge 4 near the bottom of the pit. The pile 6 is penetrated into the sludge while applying a downward pressing force under reaction of the construction machine through a buffer 8 to the vibrator 7 set on the top of the pile and also while giving a vertical vibration to the pile 6 by the vibrator 7.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for constructing concrete piles, and more particularly to a method for constructing concrete piles, in which a pile is placed in an excavated hole that has been previously excavated and turned into mud.

Conventionally, a method has been proposed in which the mud in the hole is excavated with a pre-auger and then the mud is deposited in the hole, but in both methods, the mud in the hole becomes compacted due to the penetration of the pile, resulting in the pile being crushed. In many cases, the piles were impenetrable or the piles were broken, making it impossible to sink the piles.

This invention solves these conventional drawbacks that occurred when sinking piles in a drilled hole that has been previously excavated and agitated to become muddy soil, and it is surprising to find that it is possible to sink piles while giving vertical vibrations. They discovered that the phenomenon of compaction of mud and the phenomenon of fracture of piles due to the penetration of piles as in conventional construction methods did not occur, and the present invention was completed. That is, the present invention installs a vibrator at the top of the pile when depositing a pile in an excavated hole that has been excavated and stirred in advance, and at the same time vibrates the pile while pulling the vibrator downward. This is a construction method that uses vibration press-fitting.

When excavating a hole in which a pile is to be deposited according to the present invention and turning the soil into mud by stirring, for example, as shown in FIG. Stir the soil with step 3,
It turns into mud due to groundwater in the ground. At this time, if there is a lack of moisture, it is preferable to excavate the ground 1 while spraying water or bentonite liquid from the tip of the auger as necessary.Also, as shown in Fig. It is preferable not to discharge it outside.

Excavate in this manner until the auger tip reaches the supporting ground. In addition, before sinking the mud in the hole that has been turned into mud in this way, cement milk is spouted from the tip of the auger to make the area near the tip of the hole into a mixture 5 of cement milk and mud 4, and the auger is pulled up. Reduce emissions as much as possible.

Figure 2 shows the auger in a raised state.

Figure 3 shows a concrete pile 6 being sunk into an excavated hole, where a vibration device 7 installed at the top of the pile receives a downward pushing force from the construction machine as a reaction force via a shock absorber 8. The stake is vibrated and press-fitted by applying vertical vibration to the stake 6 by the vibrator 7.

The shock absorber 8 suppresses the excessive tensile force generated on the shear wire rope due to the vertical movement of the vibrator 7, and at the same time stores the energy at that time internally, and effectively acts as a force for pushing the peg when the peg is lowered. It has the function of

In addition, to further strengthen the pushing force of the pile, install a load plate 9 on the vibrator 7 as shown in Figure 3.To make the pile sinking more effective, see Figure 5 (2).

It is best to leave the difficult tip open as shown in (3) and make the tip of the nail cone-shaped as shown in Figure 5 (1).

When the tip of the pile reaches the supporting ground (fc), the pile is sufficiently penetrated into the supporting ground to complete the sinking, and the vibrator 7 installed at the top of the pile is removed to complete the construction as shown in Fig. 4.

In the present invention, since the vibrator 7 and the peg 6 are not fixed to each other, only the downward compressive force by the vibrator is applied to the peg, and the tensile force is not transmitted, so that vibration can be effectively applied. At the same time, it is also possible to prevent cracks caused by tensile forces that occur when the length of the stakes becomes longer.

Depending on the construction method, the pile length may be ao7. As a result of constructing 10 piles in the ground of H, it was possible to sink all of the piles in 30 mt, and no cracks occurred in the concrete piles.

The present invention does not require large-scale equipment such as difficult rotating equipment, does not damage piles, and does not cause compaction of mud due to pile penetration, which was thought to be impossible with conventional construction methods. To provide a method for sinking piles without any trouble.

[Brief explanation of drawings]

Diagram M1 is a cross-sectional view of a drilled hole showing mud being turned into mud by an auger. Figure 2 is a cross-sectional view of a drilled hole that has been turned into mud. FIG. 3 is a schematic front view showing the state of vibration press-fitting of piles by a vibrator. . Figure 4 is a cross-sectional view of the excavation hole after the pile has been placed. Figure 5 (1) Front view of the tip of the pile, (2), (3
) Open cross-sectional view of the tip of the pile. １・・・・・・・・・Ground 2・・・・・・ Earth Oaker 3・・・・・・
...Non-helical blade 4...Mud work 5...Cement mill and mud mixture 6...Conc IJ -) Pile 7...
... Vertical vibration vibrator 8 ... Shocking device Patent applicant Asahi Kasei Kogyo Co., Ltd. Figure 4 Figure 5 (2) (3) Procedural amendment document ■ 1988 1. Mr. Kazuo Wakasugi, Commissioner of the Japan Patent Office 1. Indication of the case: Patent Application No. 129381 of 1988 2. Name of the invention: Concrete pile construction method 3. Person making the amendment. Relationship with the case. Patent applicant 4. Amendment. Date of Order 8i October 1, 1158 (Delivery Date 5B, 10.2
5) 5. Correction target drawing 6, correction details Figure 3 will be corrected as shown in the attached sheet. m--4-1- Figure 3

Claims (1)

[Claims] A pile construction method in which the pile is sunk while applying vertical vibration to the pile in an excavated hole that has been excavated and stirred to become muddy soil, and is characterized by applying a downward load to the vibrator installed on the pile head via a shock absorber. Construction method of concrete piles