JPH06193057A - Guide pipe for compaction pile - Google Patents

Abstract

PURPOSE:To ensure the easier driving of a compaction pile into a subsoil at the forward end of a guide pipe by fitting the forward end of the guide pipe with a material such as a sponge having compressibility and flexibility capable of preventing placed concrete from flowing toward the forward end. CONSTITUTION:A plurality of guide pipes 2 integrated and fixed with fasteners 6 are arranged approximately at the center of a drilled pit 5. Sponge 4 at the forward end of each guide pipe 2 is suitably deformed under compression against the uneven bottom of the pit 5 and made to adhere thereto, thereby forming closed state with no gap between the bottom and the end of each guide pipe 2. The guide pipes 2 are erected in this state. According to this construction, even when building frame concrete 3 placed from the ground flows toward the bottom of the pit 2, the sponge 4 works as a protective division, and prevents the concrete 3 from flowing to the forward end of the guide pipe 2.

Description

Detailed Description of the Invention

[0001]

This invention relates to the construction of a cast-in-place concrete pile, a continuous underground wall, or an embedded pile using a precast concrete pile (hereinafter referred to as cast-in-place concrete pile, etc.) with its tip supporting force. The present invention relates to a guide pipe used when penetrating a strengthening compaction pile into the tip ground (hole bottom ground).

[0002]

2. Description of the Related Art Conventionally, in the construction of cast-in-place concrete piles and the like, there has been a problem that the tip ground loosens due to excavation and the tip supporting force is lowered, and it is disclosed in JP-A-63-312419.
In the construction method described in the publication, a construction method is proposed in which after the poured concrete develops strength, a compaction pile is penetrated into the tip ground to compact the tip ground and enhance the bearing capacity. Further, various guide pipes used for such a construction method for cast-in-place concrete piles have been developed and filed (Japanese Patent Application Nos. 2-341238 and 2-3412).
No. 39, No. 2-407579, etc.). For example, in the application relating to Japanese Patent Application No. 2-341238, the strength to such an extent that the tip opening of the guide pipe can be broken by a compaction pile so that poured concrete or the like does not flow back into the guide pipe. There is described a guide pipe that is watertightly sealed with a lid having a.

[0003]

The guide pipe used for constructing the above-mentioned cast-in-place concrete pile is conventionally
It is to be installed in the excavation hole after excavation of pile holes and before placing the concrete, but after placing the guide pipe at the predetermined position on the bottom of the hole, the placed concrete is concerned. It may wrap around the tip of the guide pipe. In particular, as shown in FIGS. 4A and 4B, the hole bottom of the large-diameter excavation hole b in which a plurality of guide pipes a ... Is simultaneously installed by the fixture d is often not flat. Therefore, the pouring concrete c is likely to go around the gap p formed between the bottom of each guide pipe a and the hole bottom. If the concrete c that has entered the gap p at the tip of the guide pipe is solidified, there will be a large resistance when the compaction pile penetrates into the tip ground (hole bottom ground) e, and the penetration of the compaction pile will occur. It cannot be done smoothly, and it becomes difficult to reliably and quickly compact the tip ground e. In this respect, for example, in the guide pipe according to Japanese Patent Application No. 2-341238 described above, the cover prevents the pouring concrete from flowing into the guide pipe, but the pouring concrete that wraps around the tip of the guide pipe does not There is a problem that it cannot be prevented and the compaction pile cannot penetrate smoothly.

Therefore, an object of the present invention is to further improve the previously-applied guide pipe and prevent the cast concrete from wrapping around at the tip of the guide pipe when a cast-in-place concrete pile or the like is constructed. The purpose of the present invention is to provide a guide pipe for a compacting pile, which can more easily and surely penetrate the tip soil of the compacting pile.

[0005]

As a means for solving the above-mentioned problems of the prior art, a guide pipe for a compaction pile according to the present invention is a cast-in-place concrete as shown in the embodiments in FIGS. In a guide pipe 2 that guides a compacting pile 1 that penetrates into the ground of a drilling hole such as a pile from the ground to the bottom of the hole, compression that can prevent the casting concrete 3 from wrapping around the tip of the guide pipe 2. A material 4 such as a sponge having flexibility and flexibility is attached.

[0006]

[Function] Since the material 4 such as sponge having high compressibility and flexibility is attached to the tip of the guide pipe 2 (Fig. 1), when the tip is set on the bottom of the excavated hole, , The sponge 4 is appropriately compressed, the tip of the sponge 4 is brought into close contact with the hole bottom, and the gap between the uneven drill hole bottom and the tip of the guide pipe 2 is closed (FIG. 2B). Therefore, the cast concrete concrete 3 does not flow around into the tip of the guide pipe 2 and flow into it. The compaction pile 1 that has reached the tip of the guide pipe 2 pierces (or passes) the center portion of the sponge 4 as it is and smoothly penetrates into the tip soil 7, and the tip soil 7 is reliably compacted (Fig. 3).

[0007]

EXAMPLE An example of the present invention shown in the drawings will be described below.
The guide pipe 2 shown in FIG. 1 is for guiding the compaction pile 1 that penetrates into the ground of the excavation hole bottom of a cast-in-place concrete pile from the ground to the bottom of the excavation hole. An iron pipe having an inner diameter slightly larger than the diameter (usually about 10 to 60 cm) and a length equal to or greater than the depth of the pile hole is used.

A material 4 such as a sponge formed into a cylindrical shape having a diameter of about 15 cm and a diameter substantially the same as that of the guide pipe 2 is attached to the tip of the guide pipe 2. The material 4 such as the sponge has a large compressibility and is flexible enough to prevent the cast concrete 3 from wrapping around and to prevent the compaction pile 1 from penetrating into the tip ground 7. It is supposed to be deformable according to the shape of the hole bottom. Therefore, any material other than sponge may be used as long as it is of the same quality. Further, various shapes of the sponge 4 are also implemented according to the tip shape of the guide pipe 2. The sponge 4 of FIG. 1A is formed in a cylindrical shape so as to correspond to the end of the guide pipe 2 which is closed, and the sponge 4 of FIG.
1C has a central portion formed in a hollow cylindrical shape so as to correspond to the one in which the center of the distal end is partially opened.
The sponge 4 is also formed in a cylindrical shape so as to correspond to the one in which the tip end of the guide pipe 2 is opened, and is preferably implemented corresponding to the tip end shape of the guide pipe 2.

FIG. 2 shows a case where the guide pipe 2 is used in a large-diameter drilling hole 5 as a preferred embodiment. A plurality of guide pipes 2 which are integrally fixed by a fixture 6 are installed at a substantially central position of the excavation hole 5 (see FIG. 2A). Each sponge 4 at the tip of the guide pipe is appropriately compressed and deformed against the uneven bottom of the drilling hole, and is closely adhered to the bottom of the drilling hole, so that there is no gap between the bottom of the drilling hole and the tip of the guide pipe. Each guide pipe 2 ... is erected (FIG. 2B). Therefore, even if the skeleton concrete 3 cast from the ground flows into the bottom of the excavation hole, the sponge 4 acts as a protective wall so that the concrete 3 wraps around the tip of the guide pipe 2. There is no. Of course, there is no fear that the concrete 3 will flow into the guide pipe 2 (see the figure). After that, the compacting pile 1 that has reached the tip of the guide pipe 2 by using the guide pipe 2 pierces (or passes) the sponge 4 having compressibility and flexibility as it is, and then continues to the tip ground 7. Since it penetrates smoothly into the inside, a high-resilience cast-in-place concrete pile or the like in which the tip soil 7 is reliably compacted by the compaction pile 1 can be smoothly constructed (Fig. 3).

[0010]

According to the guide pipe for the compaction pile according to the present invention, the compaction pile 1 smoothly and reliably penetrates into the tip ground 7 to effectively exert the compaction effect. It contributes to the smooth construction of cast-in-place concrete piles with high tip support capacity, and to the construction of structures with high workability, quality, and reliability.

[Brief description of drawings]

1A to 1C are cross-sectional views showing a guide pipe of the present invention.

2A and 2B are a plan view and a cross-sectional view showing a usage example of a guide pipe.

FIG. 3 is a cross-sectional view showing a penetration state of the compaction pile.

4A and 4B are a plan view and a cross-sectional view showing a conventional example.

[Explanation of symbols]

 1 Compaction pile 2 Guide pipe 3 Casting concrete 4 Sponge

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Kiyoshi Yamashita Kiyoshi Yamashita 2-5-14 Minamisuna, Koto-ku, Tokyo Inside the Takenaka Corporation Technical Research Institute (72) Inventor Tomio Tsuchiya 2--5, Minamisuna, Koto-ku, Tokyo No. 14 Incorporated Takenaka Corp. Technical Research Institute (72) Inventor Makoto Nagasokabe 2-5-14 Minamisuna, Koto-ku, Tokyo Incorporated Incorporated Takenaka Corp. Technical Research Institute (72) Takeshi Yamada Koto-ku, Tokyo 2-5-14 Minamisuna Takenaka Corporation Technical Research Institute

Claims (1)

[Claims] 1. A guide pipe for guiding a compaction pile, which penetrates into the ground of a drilled hole bottom such as cast-in-place concrete pile, from the ground to the bottom of the hole, at the tip of the guide pipe, wrapping the cast concrete around the tip. A guide pipe for a compaction pile, which is provided with a material such as a sponge having compressibility and flexibility that can prevent