JP3072571B2 - Construction method of high strength cast-in-place concrete pile and compacted pile used for this construction method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cast-in-place concrete pile, a continuous underground wall, or a buried pile (hereinafter collectively referred to as a high-strength cast-in-place concrete pile). The present invention relates to a method for constructing a high-strength cast-in-place concrete pile with increased strength and a compacted pile used in this method.

[0002]

2. Description of the Related Art Hitherto, in the construction of cast-in-place concrete piles and the like, it has been a problem that the tip supporting force is reduced due to loosening of the tip ground due to excavation, and various improvements have been filed (prior application). And Japanese Patent Application Laid-Open No. 63-324419. Generally, as shown in FIG. 6, after the concrete body a has developed strength, the compacted pile c is inserted into the supporting ground d using the guide pipe b.
A construction method has been proposed in which the support ground d is compacted by penetrating the ground to increase the support force.

Further, when cement milk, mortar or the like is injected into the supporting ground at the same time as the compaction pile is penetrated, the tip supporting force can be further enhanced. Describes a construction method of filling cement milk or the like to a predetermined level in a hollow portion of a collar serving as a compaction pile and a guide pipe left in a supporting ground.

[0004]

In the above-mentioned conventional compacted pile, the spouting hole for cement milk or the like is blocked by so-called clogging of earth and sand, and the cement milk or the like is spouted and injected into the supporting ground. Is difficult. In addition, there is a weak place in the support ground layer, and it is difficult to inject cement milk or the like into the support ground having various soils, which is a problem to be solved.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a method of constructing a high-load cast-in-place concrete pile or the like which can surely inject cement milk or the like into various soil-supporting grounds and further enhance the tip supporting capacity. An object of the present invention is to provide a compacted pile used for a construction method.

[0006]

As a means for solving the above object, according to an aspect of, construction methods such as high strength-place concrete piles according to the invention described in claim 1, place concrete piles or underground diaphragm walls or In the construction method for embedded piles, etc., the tip cutter and the side cutter are placed in the guide pipe installed in the borehole or in the ready-made pile built in the borehole.
And an injection pipe for cement milk etc. in the axial direction
Is pierced, and the ejection port branched from the injection pipe is
The compacted pile, which is opened behind the
A step of reaching the inserted supporting ground attached to the tip of, while rotating the compaction pile by penetration rod penetrated to the desired depth in the supporting ground, at the same time the jet of該締compaction pile
A step of injecting the holes into the support ground by jetting the cement milk or the like, a compaction pile separately from penetration rod left in the supporting ground, compaction transmural input rod pulling while ejecting cement milk or the like from the distal end a step of filling the cement milk or the like to a predetermined level of the guide pipe or the ready-made pile on the pile, that more composed characterized.

A compacted pile according to a second aspect of the present invention is a compacted pile used for construction of a high-strength cast-in-place concrete pile or the like, the tip of the compacted pile projecting forward from the tip end face of the compacted pile. cutter is attached, together with the outer peripheral surface is mounted the side cutter, compaction pile
An injection tube of cement milk or the like is penetrated in the axial direction,
An ejection hole branched from the injection pipe is opened at a position behind each of the cutters in the penetration rotation direction. The invention described in claim 3 is described in claim 2.
High-strength cast-in-place concrete piles, etc.
In compaction piles used for construction of, have a spiral cutter is attached to the distal end outer peripheral surface of the compaction pile
Along with the cement milk, etc. in the axial direction of the compacted pile.
A plurality of orifices penetrated by an inlet pipe and branched from the inlet pipe;
Are respectively opened at positions behind the spiral cutter with respect to the penetration rotation direction.

The invention described in claim 4 is claim 2 or
In the compacted pile described in 3, the opening of the jet hole is
A thin plate check valve for controlling the ejection of cement milk or the like is provided. Claims according to claim 5
Ming is a compacting odor according to claim 2 or 3 or 4.
Te, the leading end apertures of the injection holes is characterized in that it is enlarged is formed in the recess.

[0009]

[Action] Cutters 4, 4 in the rotation direction of compaction pile 3
A jet hole 7 for jetting cement milk 9 and the like is formed at a position behind the spiral cutter 4 and the spiral cutter 5 (FIG. 2). 4th class acts as a partition, so to speak.
The soil and the like coming in from the rotating direction are blocked by the cutter 4 and the like, so that soil and the like are prevented from entering the ejection holes 7, so there is no danger of clogging, and the cement milk 9 and the like are surely discharged from the ejection holes 7. It is ejected and injected into the supporting ground 11 (FIG. 1B).

[0010] A thin check valve 10 for controlling the ejection of the cement milk 9 or the like is attached to the opening of the ejection hole 7 (FIG. 3). (Fig. 4), the intrusion of earth and sand can be more reliably prevented,
The cement milk 9 and the like can be smoothly ejected and injected into the support ground 11 of various soils.

[0011]

Next, an embodiment of the present invention shown in the drawings will be described. 1A to 1D show essential process charts in constructing a high-bearing cast-in-place concrete pile. FIG. 1A shows a state in which a guide pipe 2 is installed in an excavation hole excavated to a depth reaching a support ground 11, concrete is poured into the excavation hole and cured to construct a pile skeleton 1. The stage at which the compaction pile 3 is inserted into the pipe 2 by the penetrating rod 8 and reaches the support ground 11 is shown.

The compaction pile 3 is formed in an inverted conical shape having a maximum outer diameter of about 30 cm and a height of about 60 cm, and an injection pipe 6 of cement milk or the like penetrates in the axial direction (see FIG. 2). ). Tip cutters 4 and 44 projecting forward from the tip end face of the compaction pile 3 are mounted facing each other, and a side cutter 44 is attached to the outer peripheral face of the compaction pile 3 (FIG. 5C). ). However, as for this cutter, as shown in FIGS. 5A and 5B, only the tip cutter 4 is attached to the tip of the compaction pile 3. The cutters 4, 44 with respect to the rotation direction of the compaction pile 3
At the position behind the injection pipe 7, an injection hole 7 for discharging cement milk 9 (or mortar, concrete, or the like) is formed by branching off from the injection pipe 6 (FIG. 2). A spiral cutter 5 for facilitating the penetration is attached to the outer peripheral surface of the tip of the compaction pile 3, and a position behind the spiral cutter 5 in the rotation direction of the compaction pile 3 (spiral cutter) 5 (directly below 5), a plurality of ejection holes 7 are formed (FIGS. 2 and 5).
D).

FIG. 1B shows that by rotating the penetrating rod 8, the compaction pile 3 attached to the tip of the penetrating rod 8 penetrates to a desired depth in the support ground 11 while rotating, and at the same time, This shows a stage in which cement milk 9 and the like are ejected from the ejection holes 7 formed behind the cutters 4 and 44 and the spiral cutter 5 attached to the distal end portion and the outer peripheral surface and injected into the support ground 11. As described above, the ejection hole 7 is formed at a position behind the cutter 4 or the like with respect to the rotation direction of the compaction pile 3, and the compaction pile 3 advances in the supporting ground 11 while rotating. Since the cutter 4 and the like play a sort of role as a partition and protect the earth and sand from entering the vent hole 7, there is no fear of so-called clogging.
The cement milk 9 and the like are surely ejected from the ejection holes 7 and injected into the support ground 11.

FIG. 1C shows that after the injection of the cement milk 9 or the like into the supporting ground 11 is completed, the compacted pile 3 is separated from the penetrating rod 8 at the joint portion and is left in the supporting ground 11, and at the same time, the penetrating rod 8 shows a stage in which the penetration rod 8 is pulled up while the cement milk 9 or the like is further ejected from the tip of the cement milk 8 and the cement milk 9 or the like is filled to a predetermined lower level in the guide pipe 2.

Accordingly, the compacting effect is reliably exerted by the cement milk 9 or the like which is surely injected into the supporting ground 11, and a large tip supporting force of the cast-in-place concrete pile is obtained. FIG. 1D shows a stage where cement milk 9 or the like is injected into the support ground 11 and the required number of compacted piles 3 are constructed for each guide pipe 2 of one pile body 1 in the above-described manner. .

[0016]

Different Embodiment A thin plate check valve 10 for controlling the ejection of cement milk 9 or the like is attached to the opening of the ejection hole 7 according to the soil as shown in FIG. 3, or the ejection hole 7 as shown in FIG. The diameter of the tip opening is increased to form a concave portion 7a, thereby reducing the earth pressure applied to the ejection hole 7. Intrusion of earth and sand can be more reliably prevented, and cement milk 9 and the like can be smoothly spouted and injected into the support ground 11 having various soil types.

[0017]

[Second Embodiment] In the construction of a high-strength continuous underground wall foundation or a high-strength embedded pile not shown, the compacted pile 3 is used similarly to the case of the high-strength cast-in-place concrete pile. As a result, the cement milk 9 and the like can be reliably injected into the supporting ground 11, and the compaction effect is reliably exhibited, so that a large tip supporting force can be obtained.

[0018]

[Effects of the present invention] The method for constructing a high-strength cast-in-place concrete pile or the like according to the present invention and the compacted pile used in this construction method reliably inject cement milk 9 or the like into the support ground 11 of various soil types. In addition, since the tip support force can be further enhanced, the compaction effect of the support ground 11 is extremely large, and a high-proof cast-in-place concrete pile having a large tip support force can be provided. Contributes to the construction of high structures.

[Brief description of the drawings]

1A to 1D are cross-sectional views showing essential steps of a construction method according to the present invention.

FIG. 2 is an enlarged view of a compaction pile.

FIG. 3 is an enlarged view showing a different embodiment.

4A and 4B are side views showing different embodiments.

FIGS. 5A to 5D are a front view and a bottom view showing a mounting mode of the cutter.

FIG. 6 is a sectional view showing a conventional example.

[Explanation of symbols]

 2 Guide Pipe 3 Compaction Pile 8 Penetration Rod 11 Support Ground 3 Compaction Pile 9 Cement Milk 4 Tip Cutter 44 Side Cutter 7 Spray Hole 5 Spiral Cutter 10 Thin Check Valve 7a Recess

Continued on the front page (72) Inventor Tomio Tsuchiya 2-5-114 Minamisuna, Koto-ku, Tokyo Inside the Research Institute of Takenaka Corporation (72) Inventor Makoto Nagasokabe 2-5-14-Minamisuna, Koto-ku, Tokyo Shares Takenaka Corporation Technical Research Institute Co., Ltd. (72) Inventor Takeshi Yamada 2-5-1-14 Minamisuna, Koto-ku, Tokyo Stock Company Takenaka Corporation Technical Research Institute Co., Ltd. (72) Inventor Takuhei Fukuhara 8--21 Ginza, Chuo-ku, Tokyo No. 1 Takenaka Civil Engineering Co., Ltd. (56) References JP-A-63-321419 (JP, A) JP-A-51-125908 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) E02D 5/22-5/72

Claims (5)

(57) [Claims] 1. A method for constructing a cast-in-place concrete pile, a continuous underground wall, an embedded pile, or the like, wherein a tip cutter and a side cutter are installed in a guide pipe installed in a borehole or in a ready-made pile built in the borehole. With
And the injection pipe of cement milk etc. penetrates in the axial direction
And the ejection hole branched from the injection pipe is a cutter or the like.
The compacted pile, which is opened behind the tip of the penetrating rod
A step of reaching the inserted supporting ground attached to, penetrate the compaction pile to the desired depth of the support in the ground while being rotated by a penetration rod, or the ejection holes of該締compaction pile simultaneously
A step of injecting Luo cement support in the ground by jetting the like milk, compaction pile separately from penetration rod left in the supporting ground, transmural input rod is jetted cement milk or the like from the tip <br/> length a step of filling the cement milk or the like to a predetermined level in the guide pipe or the ready-made pile on top of compaction pile up come Ra引, characterized in that it further consists, construction methods, such as high strength-place concrete piles. 2. A compacted pile used for construction of a high strength cast-in-place concrete pile or the like, wherein the compacted pile has a tip portion.
Tip cutter protrudes forwardly mounted from pile tip surface and the outer peripheral surface is mounted the side cutter
In both cases, the injection pipe for cement milk etc.
There is a through, ejection holes branched from said injection pipe, characterized in that it is opened <br/> behind a position of the respective cutter relative to the penetration times <br/> rotation direction, compaction Pile. 3. A compaction pile for use in construction, such as high strength place concrete pile, the spiral cutter is attached to the distal end outer peripheral surface of the compaction pile co
In addition, an injection pipe for cement milk etc.
A plurality of orifices penetrated and branched from the injection pipe,
Characterized in that it is respectively opened in the position where the rear of the spiral cutter relative to input rotation direction, compaction pile as set forth in claim 2. 4. The compacted pile according to claim 2 , wherein a thin check valve for controlling the ejection of cement milk or the like is attached to the opening of the ejection hole. Tip opening port 5. ejection hole is characterized in that is expanded is formed in the recess, compaction anti according to claim 2 or 3 or 4.