JPH0571124A - Forming method for foundation pile - Google Patents

Abstract

PURPOSE:To promptly and inexpensively form a foundation pile by digging the ground or earth and sand through a digging tool, inserting a reinforcing member formed of a steel frame or the like in a digged hole, and filling up the filler of concrete or the like in the hole. CONSTITUTION:A reinforcing member 14 is previously attached to a digging tool 13 having enlarging diameter bits 5A, 5B which can peripherally enlarge their diameters at its tip, and the digging tool 13 and the reinforcing member 14 are slidably inserted in a cylindrical casing tube 7. The enlarging diameter bits 5A, 5B are protruded from the tip of the casing tube 7, and enlarged in their diameters to execute digging. After digging, as the digging tool 13, the reinforcing member 14 and the casing tube 7 are left in a digged hole, the filler 15 of concrete or the like is filled up in the digged hole 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing various foundation piles used for buildings and the like, in which a ground or earth and sand is excavated using an excavation tool, and a reinforcing member made of steel or the like is provided in the formed hole. The present invention relates to a method for quickly and inexpensively forming a foundation pile which is inserted and further filled with a filler such as concrete in the hole.

[0002]

2. Description of the Related Art As a method of excavating a hole in the ground to form a foundation pile, the following methods have been conventionally known. The process will be described with reference to FIGS.

FIG. 6 is a view showing a situation of excavation using a general excavation tool used for producing the conventional foundation pile. The drilling tool used here is called a down-the-hole bit, and a hammer (not shown) driven by compressed air and a bottom surface of the device 22 which receives the impact force and the rotational force of the hammer cylinder 21, Device 2
A bit 23 having a substantially disk shape with a diameter larger than the diameter of 2 and having a large number of chips 4 planted on the tip surface is attached.

Then, the hammer 23 and the hammer cylinder 21 strike the ground continuously while the bit 23 is gradually rotated by the striking force and the rotating force of the hammer 21. As a result, the bit 2
The ground 10 is locally crushed and sheared by the action of its own weight of 3 and the tip 4 to excavate.
Further, the earth and sand generated by the excavation move upward from the gap γ formed between the hole wall of the excavation hole 11 formed as a result of the excavation and the side surface of the hammer cylinder 21 due to the pressure of the compressed air that is the driving source of the hammer. Is discharged to.

FIG. 7 is a view showing the installation of the reinforcing member 25 in the excavation hole 11 and the filling material 15 in the above conventional foundation pile production.
It is a figure which shows the filling condition of. When the excavation is completed, the excavation tool is pulled up from the excavation hole 11, and then the excavation hole 1
A reinforcing member 25 made of a steel frame, a reinforced cage, or the like is installed in the inside of 1, and a filler 15 such as concrete is further filled therein.

On the other hand, as shown in FIG.
After pulling up the drilling tool from the drilling hole 11, a casing tube 26 for covering the hole wall of the drilling hole 11 and preventing the collapse of the hole wall is inserted into the drilling hole 11, and then as shown in FIG. In addition, there is also a method of installing the reinforcing member 25 in the excavation hole 11 and filling the filling material 15. in this case,
The inner diameter of the drill hole 11 must be sufficiently larger than the outer diameter of the casing tube 26 so that the casing tube 26 can be inserted.

[0007]

However, in the above-described conventional method for forming a foundation pile, after the excavation is completed, the excavation tool is temporarily pulled up from the excavation hole 11 and then the reinforcing member 25 or the casing tube 26 is required to be inserted again. was there. Moreover, when the casing tube 26 is inserted, the inner diameter of the excavation hole 11 is set to the casing tube 26.
Not only is it necessary to perform excessive excavation for the purpose of making it sufficiently larger than the outer diameter of the pile, but the gap δ formed between the inner diameter of the excavation hole 11 and the outer diameter of the foundation pile is large. Then, the foundation pile may become unstable, and as a result, for the purpose of enhancing the stability of the foundation pile, an operation such as injecting a new filler 15 into the gap δ after the foundation pile is created, if necessary. Had to do. And each of them complicates the process of creating the foundation pile and reduces workability, resulting in extension of the construction period,
As a result, there has been a problem that the construction cost including labor cost rises.

[0008]

According to the present invention, a drilling tool having a drilling member such as a bit at its tip is used for drilling, and a reinforcing member made of a steel frame or the like is inserted into the formed drilling hole. In addition, in the method of creating a foundation pile that fills a filler such as concrete in the excavation hole,

The reinforcing member is mounted on the excavating tool in advance, and the reinforcing member is inserted into the excavation hole simultaneously with excavation,
After the excavation is finished, the method for producing a foundation pile is to fill the excavation hole with a filler such as concrete in a state where the excavation tool and the reinforcing member are left in the excavation hole.

[0010]

In the present invention, after the excavation is completed, the excavation tool and the reinforcing member are left in the excavation hole to fill the excavation hole with a filler such as concrete to form a foundation pile. .. As a result, the manufacturing process is greatly simplified, and the manufacturing process can be performed quickly, so that workability is improved. Therefore, the construction period is shortened, and accordingly, the construction cost including the labor cost is saved.

[0011]

Embodiments of the present invention will now be described in more detail with reference to the drawings.

Examples of excavation equipment used in the present invention are shown in FIGS. This drilling equipment includes a drilling tool 13 that actually performs drilling, a reinforcing member 14 attached to the outer periphery of the drilling tool 13, a casing tube 7 that covers the drilling tool 13 and the periphery of the reinforcing member 14, and a casing of the drilling tool 13. The tube 7 includes a reduced-diameter tube 9 that restricts the movement of the tube 7 in the distal direction.

Of these, the excavation tool 13 is mounted on the bottom surface of the device 2 which receives the impact force of a hammer (not shown) driven by compressed air and the rotational force of the hammer cylinder 1, with respect to the center of the device 2. Two shaft holes 2A and 2B in point symmetry
And the bit shafts 3A, 3
B is rotatably mounted around the axis and is fitted in such a manner that it does not come off and has a substantially semicircular shape with a diameter substantially the same as the diameter of the device 2 at the tip end of each bit shaft 3A, 3B, and a large number of tips. Expanding bits 5A and 5B in which tips 4 are planted are provided with their straight end surfaces 6A and 6B facing each other, and bit shafts 3A and 3B.
When the device 2 rotates in the predetermined direction, one end of each of the expanding bits 5A and 5B both protrudes from the outer peripheral surface of the casing tube 7 by a predetermined amount of excavation, and at that time, The straight end surfaces 6A and 6B are eccentric from the center of the device 2 so that they come into contact with each other.

On the side surface of the hammer cylinder 1, a reinforcing member 14 made of a steel frame, a rebar cage or the like is integrally attached by welding or another method.

The casing tube 7 has a cylindrical shape, and the excavation tool 13 and the reinforcing member 14 are slidably inserted therein. Further, on the inner circumference of the tip portion of the casing tube 7, a diameter-reducing tube 9 that fits with the diameter-expanding portion 8 formed on the outer peripheral surface of the device 2 is fixed by welding or another method.

Next, a method of making a foundation pile according to the present invention using the above-mentioned excavation equipment will be described.

FIG. 4 shows a situation of excavation in this embodiment. In this case, the device 2 is moved by the hammer cylinder 1 in a predetermined direction (arrow X in FIG. 2) with the diameter-enlarging bits 5A and 5B protruding from the tip of the casing tube 7.
When the bit is expanded, the diametrical expansion bits 5A and 5B rotate about the bit shafts 3A and 3B by the excavation resistance from the state shown in FIG. 2, and as a result, as shown in FIG. One end of the straight end surfaces 6A, 6B of 5B protrudes from the outer peripheral surface of the casing tube 7 by a predetermined amount, and part of the straight end surfaces 6A, 6B abut each other, and the rotation of the diameter-enlarging bits 5A, 5B stops. To do. In this state, when the impact force of the hammer and the rotational force of the device 2 are applied to the diameter-enlarging bits 5A and 5B, the diameter-enlarging bits 5A and 5B rotate together with the vertical movement, and the weight of the diameter-enlarging bits 5A and 5B and the tip 4 of the chip 4 are rotated. Due to the action, local crushing and shear failure of the ground 10 occur, and excavation is performed.

On the other hand, the impact force of the hammer is transmitted to the casing tube 7 at the same time as the excavation due to the contact between the enlarged diameter portion 8 and the reduced diameter pipe 9 caused by the vertical movement, and the impact force and the own weight of the casing tube 7 The tip of the casing tube 7 is pushed into the ground 10. In this case, since the reduced diameter pipe 9 is located below the enlarged diameter portion 8, the impact force is transmitted only in the direction of pushing the casing tube 7 into the ground 10,
As a result, collapse of the hole wall due to water or the like leaching from the hole wall of the excavation hole 11 is effectively prevented.

The earth and sand generated as a result of the excavation is compressed air discharged when a hammer piston (not shown) falls in the hammer cylinder 1 and is blown out from air holes 12A and 12B provided on the bottom surface of the device 2. By doing so, it is separated from the tip of the excavating tool, and is further discharged upward from the gap α formed between the outer periphery of the casing tube 7 and the excavating hole 11.

Here, in the present embodiment, the excavation hole 11
Even if the width of the gap β formed between the hole wall of the excavation hole 11 and the side surface of the hammer cylinder 1 increases with the expansion of the casing tube 7, the casing tube 7 is replaced with a casing tube having a larger diameter. Outer periphery of 7 and drill hole 1
1 can be reduced by reducing the gap α formed between
It is possible to reduce the difference between the sectional areas of A and 12B and the sectional area of the gap α. As a result, even when the diameter of the excavation hole 11 is enlarged, the pressure drop of the compressed air in the gap α is small, and therefore, even for the excavation hole 11 having a large diameter, a drilling tool using compressed air as a drive source can be provided. It is possible to excavate.

After the completion of excavation, the drive source is stopped, the hammer and the hammer cylinder 1 are separated, and only the excavation equipment remains in the excavation hole, as shown in FIG. The foundation pile is created only by filling the inside with the filler 15 such as concrete. Therefore, in the present invention, the construction period required to create the foundation pile is significantly shortened compared to the conventional method for producing the foundation pile. Further, since the reinforcing member 14 made of a steel frame, a reinforcing steel cage, or the like is integrally attached to one side surface of the hammer cylinder by a method such as welding, when the filling material 15 is filled, the reinforcing member 14 and the filling member 14 are filled. The members 15 are firmly fixed to each other, and as a result, the strength of the foundation pile is sufficient.

As described above, in the present invention, all the excavation equipment including the diameter-expanding bits 5A and 5B remain in the excavation hole 11 and the excavation equipment is used as it is as a part of the foundation pile. It is impossible to use again. However, the price of the above-mentioned excavation equipment is an amount that is sufficiently compensated for by the reduction of the construction cost including the labor cost due to the drastic reduction of the construction period according to the present invention, and as a result, in the present invention, the construction period, The construction cost has been shortened or reduced from the past.

On the other hand, as described above, since the gap α between the inner diameter of the excavation hole 11 formed by excavation and the outer diameter of the casing tube 7 inserted into the excavation hole 11 is small, the casing in the excavation hole 11 is small. The stability of the tube 7 is very high. Therefore, the casing tube 7 can be directly used as the inner wall of the excavation hole 11 without performing an operation for stably holding the casing tube 7 in the excavation hole 12. Therefore, it is possible to further simplify the process and shorten the construction period.

It should be noted that, if necessary, after the completion of excavation, the filler
It is of course possible to pull out the casing tube 7 from the excavation hole 11 before the casing tube 7 is solidified and the casing tube 7 cannot be pulled out from the excavation hole 11. Further, in order to reduce the load that the bit receives during excavation, the number of the expandable bits may be divided into three or more. Further, the present invention can be applied not only to the creation of foundation piles but also to the retention piles. It can also be applied to anchor work and various other fixed works.

[0025]

As described above, according to the present invention,
After the excavation was completed, a filler such as concrete was filled in the excavation hole while the excavation tool and the reinforcing member were left in the excavation hole to form a foundation pile. as a result,
The process of making foundation piles has been greatly simplified, and the work can be done quickly, improving workability. Therefore, the construction period was shortened, and accordingly, the construction cost including the labor cost could be saved.

[Brief description of drawings]

FIG. 1 is a partial side sectional view of excavation equipment used in a first embodiment of the present invention.

FIG. 2 is a plan view showing a state in which the diameter-expanding bit is reduced in the excavation equipment used in the first embodiment of the present invention.

FIG. 3 is a plan view showing a state in which the diameter-expanding bit is expanded in the excavation equipment used in the first embodiment of the present invention.

FIG. 4 is a partial side cross-sectional view of excavation equipment showing a situation of excavation work in the first embodiment of the present invention.

FIG. 5 is a partial side cross-sectional view of the excavation equipment showing a state when the foundation pile is completed in the first embodiment of the present invention.

FIG. 6 is a diagram showing an excavation tool used in a conventional method for forming a foundation pile and a situation of excavation work using the same.

FIG. 7 is a side cross-sectional view of the excavation equipment showing the situation at the time of completion of the foundation pile in the conventional method for producing a foundation pile.

FIG. 8 is a side cross-sectional view of the excavation equipment showing a situation when the casing tube is inserted in the conventional method for forming a foundation pile.

FIG. 9 is a side cross-sectional view of an excavation pit showing a situation at the time of completion of a foundation pile in the conventional method for producing a foundation pile.

[Explanation of symbols]

1, 21 Hammer cylinder 2, 22 Device 2A, 2B Shaft hole 3A, 3B Bit shaft 4 Tip 5A, 5B Expanding bit 6A, 6B Straight end face 7,26 Casing tube 8 Expanding part 9 Shrinking pipe 10 Ground 11 Drilling Hole 12A, 12B Air hole 13 Drilling tool 14,25 Reinforcing member 15 Filler 23 bit α, δ Gap formed between the hole wall of the drilling hole and the side surface of the casing tube inserted into the drilling hole β Drilling hole Gap formed between the hole wall of the drill hole and the side surface of the device inserted in the drill hole γ The gap formed between the hole wall of the drill hole and the side surface of the hammer cylinder inserted in the drill hole

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yoneo Hiwasa 1528, Nakashinden, Yokoi, Kobe-shi, Anpachi-gun, Gifu Prefecture Mitsubishi Materials Corporation Gifu Factory

Claims (2)

[Claims] 1. A drilling tool having a drilling member at its tip is used for drilling, a reinforcing member made of steel or the like is inserted into the drilled hole, and the drilling hole is filled with concrete or the like. In the method of creating a foundation pile to be filled with agent, the reinforcing member is attached to the excavation tool in advance, the reinforcing member is inserted into the excavation hole together with excavation, and after excavation,
A method for producing a foundation pile, comprising filling the filler in the excavation hole while leaving the excavation tool and the reinforcing member left in the excavation hole. 2. As the excavating tool, a excavating tool having a bit whose diameter can be expanded outward in the radial direction is used as the excavating tool, and the reinforcing member is attached to the side surface of the excavating tool in advance. The reinforcing member is slidably inserted in a cylindrical casing tube, the bit is projected from the tip of the casing tube, and the excavation is performed in a state in which the bit is expanded beyond the outer diameter of the casing tube. The reinforcing member and the casing tube are inserted into the excavation hole, and after the excavation is completed, the excavation tool, the reinforcing member, and the casing tube are left in the excavation hole, and the filling is performed in the excavation hole. The method for producing a foundation pile according to claim 1, wherein the foundation pile is filled with the agent.