JP2010236311A - Method for constructing pile foundation, and the pile foundation for use in the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for constructing a pile foundation, which can downsize a shape of a footing attached to an upper portion of each prefabricated pile, and the pile foundation for use in the method. <P>SOLUTION: In the method for constructing the pile foundation, two drilled holes 2 are drilled in such a manner as to communicate with each other; each of the drilled holes 2 communicating with each other is filled with cement milk (filler) 3; the prefabricated concrete pile 1 is erected in each of the drilled holes 2 filled with the cement milk (filler) 3; and the two prefabricated concrete piles 1 are integrated together by means of the cement milk (filler) 3 in a gap between each of the drilled holes 2 and the prefabricated concrete pile 1. In the pile foundation, the prefabricated concrete pile 1 is erected in each 2 of the two drilled holes 2 communicating with each other; and the two prefabricated concrete piles 1 are integrated together by means of the cement milk (filler) 3 which is infilled into the gap between each of the drilled holes 2 and the prefabricated concrete pile 1. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a method for constructing a pile foundation composed of a plurality of ready-made piles and the pile foundation.

  In the construction of a large structure, a large-diameter pile may be used, and a large-diameter ready-made pile is used, not limited to a large-diameter field pile.

However, the diameter of ready-made piles has been expanded due to the progress of technological development, but there is still an upper limit on the maximum diameter due to restrictions in manufacturing technology and standards.
Therefore, when the column load is large and the supporting force of one ready-made pile is not sufficient, it is necessary to support the column load with several ready-made piles via a footing for one column.
In that case, the ready-made pile which supports a structure is constructed with a certain space | interval maintained for every one.
And about the minimum space | interval of a pile, for example, "Architectural foundation structure design guideline" (The Architectural Institute of Japan, April 15, 2002, the 2nd edition 2nd printing), 199 pages 6-24 lines (non-) According to this description, in the case of an embedded pile, the value is at least twice the diameter of the pile.

FIG. 9 shows a conventional foundation structure, which is a foundation structure in which a footing is attached to the upper part of two ready-made concrete piles, (a) is a plan view thereof, and (b) is a sectional view thereof. .
The distance between the two ready-made concrete piles in the conventional foundation structure shown in FIG. 9 is at least twice the diameter of the ready-made concrete pile based on the description of Non-Patent Document 1.

In this case, since the distance between the two ready-made concrete piles is more than 2.5 times the diameter of the ready-made concrete piles, the load applied to the pillars is distributed and transmitted from the pillars to the ready-made concrete piles by footing. Will be.
Therefore, since the footing needs to cover the space between the two ready-made concrete piles, the footing has a corresponding size.

In addition, since the load from the column is distributed and transmitted to two ready-made concrete piles, the footing must withstand shearing force and bending stress.
Therefore, the footing has a structurally appropriate size, and this requires materials and formwork such as the required concrete strength and the amount of reinforcing bars.
In addition, such footing construction requires time and manpower.
Furthermore, extra ground excavation for the footing is often required, which also requires temporary materials, time and manpower.

Guidelines for Designing Basic Building Structures (published by the Architectural Institute of Japan, April 15, 2002, second edition, second print, page 199, lines 6-24)

  Then, an object of this invention is to provide the construction method of the pile foundation which can make the shape of the footing attached to the upper part of each ready-made pile small, and its pile foundation.

  That is, the present invention is (1) a method for constructing a pile foundation, wherein a plurality of excavation holes are excavated so as to communicate with each other, the communicating excavation holes are filled with a filler, and the filler is used. It is a construction method of a pile foundation in which a ready-made pile is installed in each filled excavation hole, and the plurality of ready-made piles are integrated by the filler in a gap between each excavation hole and the ready-made pile.

  Further, the present invention is (2) a method for constructing a pile foundation, wherein one excavation hole having a predetermined diameter is excavated, the excavation hole is filled with a filler, and the excavation hole filled with the filler is used. Is a construction method of a pile foundation in which a plurality of ready-made piles are installed together in the center of the pile, and the plurality of ready-made piles are integrated by the filler in a gap between the excavation hole and the plurality of ready-made piles.

  Further, the present invention is (3) the pile foundation construction method according to (1) or (2) above, wherein the filler is cement milk.

  Further, the present invention provides (4) a plurality of prefabricated piles built in the respective excavation holes of the plural excavation holes communicating with each other, and the plural pieces are filled with a filler filled in the gaps between the respective excavation holes and the prefabricated piles. It is a pile foundation that integrates ready-made piles.

  Further, the present invention is (5), filling a plurality of ready-made piles together at the center of one excavation hole having a predetermined diameter, and filling a gap between the excavation holes and the plurality of pre-made piles It is a pile foundation in which the plurality of ready-made piles are integrated with a material.

  Moreover, this invention is a pile foundation of the said (4) or (5) description whose said filler is cement milk (6).

  Note that a configuration in which the above (1) to (6) are appropriately combined can be adopted as long as the object of the present invention is met.

According to the pile foundation construction method and the pile foundation of the present invention, the shape dimensions of the footing can be reduced as compared with the conventional example (shown in FIG. 9).
Therefore, the cross-sectional performance of the footing can be reduced. Furthermore, by reducing the shape dimensions of the footing, it is possible to reduce the overall material, construction period and manpower.

FIG. 1 is a cross-sectional view showing a process of excavating two excavation holes communicating with each other in a construction method according to an embodiment of the present invention with a biaxial auger. FIG. 2 shows a step of filling cement milk in each of the two drilling holes communicating with each other shown in FIG. 1, (a) is a plan view of the two drilling holes communicating with each other, and (b) is a plan view. FIG. FIG. 3 is a cross-sectional view showing a state in which a ready-made concrete pile is built in each of two communicating holes filled with cement milk shown in FIG. FIG. 4 is a basic structure showing a state in which a footing is attached to the upper part of the two ready-made concrete piles shown in FIG. 3, wherein (a) is a plan view thereof and (b) is a sectional view thereof. FIG. 5 is a plan view of an excavation hole obtained by excavating three excavation holes communicating with each other in a straight line, and is a plan view corresponding to FIG. FIG. 6 is a plan view of an excavation hole obtained by excavating three excavation holes communicating with each other in a substantially triangular shape, and is a plan view corresponding to FIG. FIG. 7 is a plan view of an excavation hole obtained by excavating four excavation holes communicating with each other into a substantially square shape, and is a plan view corresponding to FIG. FIG. 8 is a plan view of another embodiment of the present invention. FIG. 9 shows a conventional foundation structure, which is a foundation structure in which a footing is attached to the upper part of two ready-made concrete piles, (a) is a plan view thereof, and (b) is a sectional view thereof. .

  A construction method of a pile foundation according to an embodiment of the present invention and the pile foundation will be described below with reference to FIGS.

  FIG. 1 is a cross-sectional view showing a process of excavating two excavation holes communicating with each other in a construction method according to an embodiment of the present invention with a biaxial auger.

  FIG. 2 shows a process of filling cement milk in each of the two drilling holes communicating with each other shown in FIG. 1, and FIG. 2 (a) is a plan view of the two drilling holes communicating with each other. (B) is a sectional view thereof.

  FIG. 3 is a cross-sectional view showing a state in which a ready-made concrete pile is built in each of two communicating holes filled with cement milk shown in FIG.

  FIG. 4 is a basic structure showing a state in which a footing is attached to the upper part of two ready-made concrete piles shown in FIG. 3, FIG. 4 (a) is a plan view thereof, and FIG. 4 (b) is a sectional view thereof.

  FIG. 5 is a plan view of an excavation hole obtained by excavating three excavation holes communicating with each other in a straight line, and is a plan view corresponding to FIG.

  FIG. 6 is a plan view of an excavation hole obtained by excavating three excavation holes communicating with each other in a substantially triangular shape, and is a plan view corresponding to FIG.

  FIG. 7 is a plan view of an excavation hole obtained by excavating four excavation holes communicating with each other into a substantially square shape, and is a plan view corresponding to FIG.

The construction method according to the embodiment of the present invention will be described below.
First, the method of embedding two ready-made concrete piles (ready-made piles) will be described.
As shown in FIG. 1, the excavation hole 2 is excavated in the ground (support layer) 6 and the intermediate ground 7 by a biaxial auger 8.
As shown in FIG. 2A, the excavation hole 2 excavated by the biaxial auger 8 is formed in a substantially gourd shape, and the two excavation holes 2 communicate with each other.

Next, as shown in FIGS. 2A and 2B, cement milk (filler) 3 is filled in the two excavation holes 2.
At that time, cement milk (filler) 3 having a large amount of cement is poured into the ground (support layer) 6 as a root-setting liquid, and cement milk (filler) 3 is filled thereon as a peripheral fixative. To do.

Next, as shown in FIG. 3, ready-made concrete piles 1 are installed in the respective excavation holes 2 filled with cement milk (filler) 3.
When the cement milk (filler) 3 is hardened, the two ready-made concrete piles 1 are integrated into a pile foundation.

With the construction method as described above, as shown in FIG. 3, the ready-made concrete piles 1 are respectively built in the two excavation holes 2 of the two excavation holes 2 communicating with each other. A pile foundation in which two ready-made concrete piles 1 are integrated by cement milk (filler) 3 filled in the gap can be formed.
In FIG. 3, 9 indicates discarded concrete and 10 indicates crushed stone.

  And as shown to Fig.4 (a) and FIG.4 (b), a foundation structure is formed by attaching a footing to the upper part of the two ready-made concrete piles 1. FIG.

Next, the example of the excavation hole 2 for constructing the three ready-made concrete piles 1 is demonstrated.
FIG. 5 is a plan view of the excavation hole 2 obtained by excavating the three excavation holes 2 communicating with each other in a straight line, and is a plan view corresponding to FIG.
In order to excavate the three excavation holes 2 in a straight line, the left and central excavation holes 2 are excavated by the biaxial auger 8 in FIG. Drill by.
That is, three excavation holes 2 are excavated linearly by digging twice by the biaxial auger 8.
Then, cement milk (filler) 3 is filled in the three excavation holes 2 communicating with each other.

Next, although not shown, the ready-made concrete piles 1 are installed in the respective excavation holes 2 filled with cement milk (filler) 3.
When the cement milk (filler) 3 is hardened, the three ready-made concrete piles 1 are integrated into a pile foundation.
And although not shown in figure, a foundation structure is formed by attaching a footing to the upper part of the three ready-made concrete piles 1. FIG.

6 is a plan view of the excavation hole 2 obtained by excavating the three excavation holes 2 communicating with each other in a substantially triangular shape, and is a plan view corresponding to FIG.
In order to excavate the three excavation holes 2 into a substantially triangular shape, the lower two excavation holes 2 in FIG. 6 are excavated by the biaxial auger 8, and then the upper excavation hole 2 is excavated by the single axial auger. .
Then, cement milk (filler) 3 is filled in the three excavation holes 2 communicating with each other.

Next, although not shown, the ready-made concrete piles 1 are installed in the respective excavation holes 2 filled with cement milk (filler) 3.
When the cement milk (filler) 3 is hardened, the three ready-made concrete piles 1 are integrated into a pile foundation.
And although not shown in figure, a foundation structure is formed by attaching a footing to the upper part of the three ready-made concrete piles 1. FIG.

Next, the example of the excavation hole 2 for constructing the four ready-made concrete piles 1 is demonstrated.
7 is a plan view of the excavation hole 2 obtained by excavating the four excavation holes 2 communicating with each other into a substantially square shape, and is a plan view corresponding to FIG.
In order to excavate the four excavation holes 2 into a substantially square shape, the lower two excavation holes 2 in FIG. 7 are excavated by the biaxial auger 8, and then the upper two excavation holes 2 are biaxial. Drilling with Auger 8.
Thereafter, cement milk (filler) 3 is filled into the four excavation holes 2 communicating with each other.

Next, although not shown, the ready-made concrete piles 1 are installed in the respective excavation holes 2 filled with cement milk (filler) 3.
When the cement milk (filler) 3 is hardened, the four ready-made concrete piles 1 are integrated into a pile foundation.
And although not shown in figure, a foundation structure is formed by attaching a footing to the upper part of the four ready-made concrete piles 1. FIG.

Next, a pile foundation construction method and pile foundation according to another embodiment of the present invention will be described below with reference to FIG.
As shown in FIG. 8, one excavation hole 2 'having a predetermined diameter (large diameter) is excavated by a large-diameter excavator (not shown).
Then, cement milk (filler) 3 is filled in the excavation hole 2 ′.

Next, three ready-made concrete piles (ready-made piles) 1 ′ are built together in the center of the excavation hole 2 ′ filled with cement milk (filler) 3.
When the cement milk (filler) 3 is hardened, the three ready-made concrete piles 1 'are integrated into a pile foundation.
And although not shown in figure, a foundation structure is formed by attaching a footing to the upper part of three ready-made concrete piles 1 '.

According to the pile foundation construction method and the pile foundation according to the embodiment of the present invention and the other embodiments, the shape dimension of the footing 4 is reduced as compared with the conventional example (shown in FIG. 9). Can do.
Therefore, the cross-sectional performance of the footing 4 can be reduced. Furthermore, by reducing the size of the footing 4, it is possible to reduce the overall material, construction period, and manpower.

In the construction method of the pile foundation and the pile foundation according to the embodiment of the present invention and the other embodiments described above, the case where the ready-made concrete pile is used as the ready-made pile has been described. It is not limited, For example, it can replace with a ready-made concrete pile and can use a ready-made steel pile.
The ready-made concrete pile and the ready-made steel pile may be solid or hollow.

1 ... Ready-made concrete pile (ready-made pile)
2, 2 '... Drilling hole 3 ... Cement milk (filler)
4 ... Footing 5 ... Pillar 6 ... Ground (support layer)
7 ... Intermediate ground 8 ... Biaxial auger 9 ... Discarded concrete 10 ... Crushed stone

Claims (6)

  A pile foundation construction method, in which a plurality of excavation holes are excavated so as to communicate with each other, a filling material is filled in the communicating excavation holes, and the excavation holes filled with the filling material are respectively ready-made piles The pile foundation construction method is characterized in that the plurality of ready-made piles are integrated with the filler in the gaps between the excavation holes and the ready-made piles.   A method for constructing a pile foundation, wherein one excavation hole having a predetermined diameter is excavated, the excavation hole is filled with a filler, and a plurality of ready-made piles are provided at the center of the excavation hole filled with the filler. A construction method for a pile foundation characterized in that the plurality of ready-made piles are integrated by using the filler in the gap between the excavation hole and the plurality of ready-made piles.   3. The pile foundation construction method according to claim 1, wherein the filler is cement milk.   A prefabricated pile is built in each excavation hole of a plurality of excavation holes communicating with each other, and the plural prefabricated piles are integrated by a filler filled in a gap between each excavation hole and the prefabricated pile And pile foundation.   A plurality of ready-made piles are built together in the center of one excavation hole having a predetermined diameter, and the plurality of ready-made piles are integrated by a filler filled in a gap between the excavation hole and the plurality of ready-made piles. Pile foundation characterized by having become. The pile foundation according to claim 4 or 5, wherein the filler is cement milk.

Images