JPS60261830A - Method of sinking concrete pile - Google Patents

Abstract

PURPOSE:To sink a pile without generating noise and vibration, by a method wherein a thrust pile is connected to the forward end of a hollow pipe, a rotary shaft is inserted into the pile, and the square block of the shaft is engaged with the engaging hole of the thrust pile. CONSTITUTION:A rotary shaft C is inserted into a hollow pile B, and a square block 8 is engaged with an engaging hole 4 of a thrust pile A. A seat plate 11 is then placed on an end plate 7 of the pile B, an auger mechanism D is placed thereon through the medium of a cap 12, and an auger joint 15 is coupled to a driving shaft 13 of a tower for sinking of the pile. With the auger mechanism D rotated, the rotation force of the shaft C is transferred to the pile A through the block 8 and the engaging hole 4, and excavation is progressed by means of a spiral blade 3 to penetrate piles A and B into the ground.

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to a method for sinking concrete piles that is suitable for efficiently carrying out sinking work without noise or vibration.

``Conventional technology'' Currently, the hammering method, pre-poling method, cement milk method, hollow digging method, etc. are used to sink concrete piles into the ground, but due to social demands,
The percussion method, which causes noise and vibration, is now being avoided in urban areas, and low-pollution construction methods that generate as little noise and vibration as possible, such as the cement milk method and the hollow digging method, are now being used.

In the cement milk method, in order to prevent the hole from collapsing using an earth auger, the ground is excavated and removed while water and bentonite or a mixture of water, bentonite, and cement is injected from the tip of the auger, and the earth is removed near the supporting ground. After excavation, cement milk (cement + water) is injected, and the area near the supporting ground is made into a cement milk column.The pile is erected in the excavation hole, the pile is sunk, and the head of the pile is tapped or press-fitted. Compared to the pre-poling method, noise and
Vibration will be further reduced, but construction costs will be higher.

In addition, in the hollow digging method, an earth auger is inserted into the hollow part of the pile, and while the auger excavates the ground, earth and sand are discharged through the hollow part of the pile to sink the pile, cement milk is injected near the supporting ground, and the auger is used to excavate the ground. After pulling out the pile, the pile is pressed in, etc., to sink the pile. This hollow construction method is cheaper than the cement milk construction method and produces less noise and vibration, so it is now more commonly used as a low-pollution construction method.

In light of this technology, there has been a desire to develop a method that is lower in construction cost than the above-mentioned methods and allows concrete piles to be sunk into the ground without noise or vibration.

In order to achieve the above objectives, concrete piles have been developed in which spiral concrete wings are provided along the entire length of the concrete pile, and a method has also emerged in which the pile is sunk into the ground by applying rotational force to the head of the pile. , has the following drawbacks.

Its disadvantages are as follows: (1) Since spiral concrete wings are provided over the entire length of the concrete pile, the formwork for manufacturing it is complicated and expensive, and the reinforcement arrangement is also troublesome, resulting in high manufacturing costs.

(2) Since the pile is sunk by applying rotation to the pile head, when the pile length becomes long, the rotational force of the pile head is difficult to be transmitted to the lower end of the pile due to the frictional force of the soil, and there is a limit to the pile length. Also, as the pile length increases, a twisting moment acts on the pile, which may cause the pile to twist and break.

can be mentioned.

"Problems to be Solved by the Invention" The present invention solves the drawbacks of these conventional construction methods, uses concrete piles that are inexpensive to manufacture, and is a construction method that can be easily sunk into the ground without noise or vibration. It aims to provide the following.

``Means for Solving the Problems'' The present invention connects a propulsion pile with a spiral plaid protruding from the outer periphery and a fitting hole with an angular cross section formed in the center at the tip of a hollow pile. Then, a rotating shaft having a square block having a shape corresponding to the fitting hole at the lower end is inserted into the connected pile, and the square block is fitted into the fitting hole, and the rotating shaft is inserted into the connected pile. The feature is that the pile is laid down while applying rotational force to the lower part of the pile.

"Embodiments" Examples of the present invention will be described below with reference to the drawings.

The drawing shows the concrete pile used in the construction method of the present invention and the rotating shaft for sinking the concrete pile, where A is the propulsion pile, B is a normal hollow pile connected to the propulsion pile and sunk, C is each of these piles A, This is a rotating shaft for applying rotational force to B.

In the propulsion pile A, the outer periphery of a concrete pile body 1 is covered with a protective iron plate 2, and one to several turns of helical plaids 3 are protruded from the outer periphery. A fitting hole 4 having a rectangular cross section is formed at the center of the base end to a required depth.

The cross-sectional shape of the fitting hole 4 is hexagonal in the drawings of the embodiment, but it can be formed into a square or other appropriate square shape. In the example drawing, it is a continuous spiral, but it may be divided into discontinuous parts and formed into a spiral shape as a whole.

Since the hollow pile B is generally used as a foundation pile, there is no need to specifically explain it, but the outer periphery of both ends of the hollow concrete body 5 is covered with protective iron plates 6, and end plates are provided on both end surfaces. 7 is provided, and shaft reinforcing bars are arranged in the main body 5.

The rotary shirt LC is provided with a lower square block 8 that loosely fits into the fitting hole 4 at its distal end, and an auger joint 9 at its base end.

The construction method of the present invention can be applied to the conventionally commonly used hollow pile B.
The hollow pile B and propulsion pile A are connected to the tip of the hollow pile A, and the ends of both piles A and B are joined together, similar to the conventional connection between piles. ,
The peripheral portions are welded 10 and joined together. Then, the rotating shaft C is inserted into the pile, and its lower square block 8 is fitted into the fitting hole 4 of the propulsion pile A. In this case, the auger joint 9 of the rotating shaft C projects upward from the upper end of the pile B.

Next, an elastic and lubricating seat plate 11 made of nylon, for example, is placed on the end plate 7 at the upper end of the pile B, an auger mechanism is placed on top of it via the cap 12, and the auger joint 15 is placed on the pile B. It is connected to the drive shaft 13 of the submerged tower. When the shaft C is rotated, the rotational force of the shaft C is transmitted to the propulsion pile A through the rectangular block 8 and the fitting hole 4, and the shaft C is rotated. Then, the excavation progresses by the spiral-shaped plaid 3 of the propulsion pile A, and the propulsion pile A and the hollow pile B connected thereto penetrate into the ground B by 3 and 7. and. □
Become.

In order to sink the hollow pile B that has penetrated into the ground deeper, connect another hollow pile to the hollow pile B, and
A connecting shaft 22 having the same length as the hollow pile to be connected may be connected to the rotating shaft C, and the following operations may be performed in the same manner.

After the pile laying work is completed, the driving shaft and the auger joint 15 are uncoupled and the rotating shaft C is pulled out.

"Operation" In the construction method of the present invention, the rotational force of the auger is applied to the propulsion pile A via the rotating shaft C. That is, the pile to be sunk is rotated by a rotational force at its lower end.

Therefore, the lower end of the pile, which is subject to the greatest resistance, is directly rotated by the notch into the ground made by the plaids 3 and the earth pressure. Therefore, almost no torsional moment acts on the entire pile, and the pile can be easily sunk.

"Effects of the Invention" As explained above, the present invention connects a propulsion pile in which a spiral plaid is protruded from the outer periphery and a fitting hole with a rectangular cross section is formed in the center at the tip of a hollow pile. At the same time, a rotating shaft having a square block having a shape corresponding to the fitting hole at the lower end is inserted into the connected pile, and the square block is fitted into the fitting hole, and the rotating shaft is rotated. Since the pile is set while applying force to the bottom of the pile, it is possible to easily sink the pile into the ground without noise or vibration. Since rotational force is applied, no twisting moment is applied to the pile, and there is no fear that the pile will be cut. In addition, since the pile has a helical plaid for excavating only at the lower end of the pile, it is easy to manufacture and can be provided at low cost.

[Brief explanation of drawings]

Figure 1 is a side sectional view showing one embodiment of a hollow pile used in the construction method of the present invention, Figure 2 is a plan view of the same, and Figure 3 is a construction state in which a rotating shaft is inserted into the hollow pile and the propulsion pile. It is a side sectional view. A... Propulsion pile B... Hollow pile C... Rotating shaft D... Auger mechanism 3... Helical plaid 4... ...
Fitting hole 8... Square block 9... Auger joint 11... Seat plate 12 River cap patent applicant Daido Concrete Industry Co., Ltd. Figure 1 Figure 3 Δ Figure 2

Claims (1)

[Claims] A propulsion pile having a spiral plaid protruding from the outer periphery and a fitting hole with a rectangular cross section in the center is connected to the tip of the hollow pile. A rotary shaft having a rectangular block having a shape corresponding to the mating hole is inserted, the rectangular block is fitted into the mating hole, and the pile is deposited while applying the rotational force of the rotary shaft to the lower part of the pile. A concrete pile sinking method.