JPS6023521A - 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 settled while giving vertical vibrations to the pile into an excavated pit where the ground is made sludgy by stirring in advance. CONSTITUTION:The ground is excavated by an earth auger 2, and the soil is made sludgy with groundwater, etc., by stirring it by a non-spiral shaped 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 a cement milk-sludge 4 mixed lump 5 near the bottom of the pit. A pile 6 is then settled into the sludge 4 while applying vertical vibration to the pile 6 by a vibrator 7.

Description

DETAILED DESCRIPTION OF THE INVENTION The present construction method relates to a method for constructing concrete, and more specifically, to a method for constructing concrete by depositing a slag in an excavated hole that has been turned into mud in advance.

Previously, a method of excavating with a Zoleauger and depositing concrete into the muddy hole had been proposed;
In either method, the mud in the hole becomes compacted due to the penetration of the piles, and as a result, the piles become unable to penetrate or break, making it often impossible to sink the piles.

This method eliminates these drawbacks of the conventional method, which occurs when a pile is placed in an excavated hole that has been previously excavated and stirred to become muddy soil. The present invention was completed based on the discovery that the compaction of mud and the breaking of piles do not occur as in conventional construction methods due to the penetration of piles. That is,
The present invention is a method for constructing concrete piles, in which the piles are placed in an excavated hole that has been previously excavated and stirred to become muddy soil, while applying vertical vibration to the pile.

When excavating a hole in which a pile is to be deposited according to the present invention and turning it into mud by stirring, for example, as shown in FIG. The soil is stirred by the blade 3 and turned into mud by groundwater in the ground. At this time, if there is a lack of water, it is preferable to excavate the ground 1 while spraying water or muddy water such as bentonite liquid from one tip of the oar as necessary.Also, it is preferable that almost no soil be discharged outside the hole during excavation. preferable. Excavate in this manner until one end of the drill reaches the supporting ground. In addition, as shown in Fig. 2, before sinking the muddy hole in the hole, cement milk is spouted from one tip of the drill and the vicinity of the tip of the hole is mixed with a mixture 5 of cement milk and mud 4. At the same time, when pulling up the auger, reduce soil removal as much as possible.

Figure 2 shows the drilled hole with the auger pulled up.

As is clear from Figure 2, this method differs from the conventional cement milk method and other ZOL-1 methods in that the soil in the borehole is only softened, leaving as much soil as possible inside the borehole. ,
This method prevents the collapse of the excavated hole, and is different from the conventional buried pile construction method, which aims to remove as much soil as possible.

Figure 3 shows the state in which the pile 6 is sunk into the excavated hole.A vertical vibration vibrator 7 is installed at the top of the pile (the pile 6 is given vertical vibration to sink it into the muddy soil). In this case, it is sufficient to use a vibrator similar to that used for driving steel sheet piles.

In order to make the sinking of the pile 6 more effective, it is recommended to make the tip of the pile open or to make the tip of the pile cone-shaped as shown in Figure 5 (11). This is an example of the state of the tip of the pile.If the tip of the pile is open, it not only improves the ability of the pile to penetrate into the excavation hole, but also allows the white soil of the excavation hole to be inserted into the hollow part of the pile. It also has the effect of reducing the amount of water released to the outside.

When the tip of the pile reaches the supporting ground, 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 Figure 4.

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.

Examples and Comparative Examples Examples of piles installed in the ground with a pile length of 20 m Types of piles External diameter of ready-made concrete piles 40! Construction method and construction method I (conventional construction method) The sludge was pressed into the borehole, which had been turned into mud by excavation and stirring. 2
Although this work was carried out, it became impossible to penetrate the piles by press-fitting alone, and it was not possible to sink the piles all the way to the support layer.

Construction method ■ (Conventional method) The soil was excavated and agitated, and the mud turned into mud was deposited in the hole while rotating. Three piles were constructed, but two of the piles were damaged during construction due to rotational force.

The construction time for the pile that could be sunk to the support layer was 35 minutes for excavation and 40 minutes for sinking the pile.

Construction method■ Construction was carried out using the construction method of the present invention. We constructed 5 pipes and were able to sink all of them to the supporting layer. Construction time was approximately 35 minutes for excavation and approximately 20 minutes for sinking piles.
It was a minute.

[Brief explanation of drawings]

Figure 1 is a cross-sectional view showing ground excavation by Earth-O.
FIG. 2 is a sectional view of the excavation hole from which the earth auger in FIG. 1... Ground 2... Earth auger 3... Non-helical blades 4... Mud 5... Mixture of cement milk and mud 6... Concrete <-1 7... Vertical movement Vibrator patent applicant: Asahi Kasei Kogyo Co., Ltd. Figure 4 Procedural amendment letter: November 2, 1980 Commissioner of the Japan Patent Office Kazuo Wakasugi 1, Indication of case: 1988 Patent Application No. 129380 2
, Name of invention Concrete pile construction method 3, ? Relationship with the Ili Correction Case Patent applicant: 1-2-6-4 Dojimahama, Kita-ku, Osaka-shi, Osaka Prefecture, date of amendment order: October 1, 1980 (shipment date: 5B, 10.25)
5. Column 6 of the specification to be amended, "Brief explanation of the drawings," Contents of amendment (1), page 6, line 3 of the specification, [This is a sectional view shown] 5th FI! Correct ``J'' to ``Cross-sectional view shown in Figure 4 and Figure 5 showing a cross-sectional view of the first hole where piles have been placed.''that's all

Claims (1)

[Claims] A method for constructing concrete piles, which is characterized by depositing piles in an excavated hole that has been previously excavated and stirred to become muddy soil while applying vertical vibration to the pile.