JPH0629517B2 - Concrete pile sinking method - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for laying concrete piles, which enables noise-free, vibration-free and efficient laying work.

“Prior Art” Conventionally, in order to sunk a concrete pile in the ground without noise and vibration, generally, an auger is used to excavate a digging hole, and the concrete pile is suspended and inserted into the hole. However, if there is excavated earth and sand in the hole, the weight of the concrete pile cannot be inserted to a predetermined depth, so that the head of the concrete pile is pressed and rotated. But with this method,
When the length of the concrete pile becomes large, 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 the settling length is limited, and when the pile length becomes large, the torsional moment of the pile becomes large. This may cause the pile to be cut off.

“Problems to be Solved by the Invention” Therefore, in order to solve the above-mentioned conventional problems, the present inventors have
As disclosed in Japanese Patent Laid-Open No. 60-59226, a propulsion pile having a spiral blade projecting from the outer periphery is connected to the tip of the hollow pile, and the rotational force of the rotary shaft is applied to the angular hole of the propulsion pile and the hollow pile. We have proposed a method of press-fitting the pile while applying it to the base end.

According to this construction method, since the rotational force is transmitted to both the tip end portion and the base end portion of the pile, the torsional moment acting on the pile can be greatly reduced. However, as a result of further research, it was found that there is a point to be improved in this method. That is, when a rotating force is applied to the tip and the base end of the pile as in the same construction method, distortion occurs due to the torsional moment of the rotating shaft, so that the rotating force of the shaft continues from the base end of the pile. Since it acts on the tip part, a twisting moment is also generated in the pile by that much, which is not preferable, and the engagement mechanism between the base end part of the pile and the rotary shaft becomes complicated, and the work is troublesome. There is a problem that is.

The present invention solves such a problem, and when the pile is sunk, while suppressing the torsional moment acting on the pile to a minimum, the staking work can be performed easily and efficiently, and a construction method capable of reducing the construction cost can be provided. It is the one we are trying to provide.

"Means for Solving Problems" The structure of the present invention will be described with reference to the drawings corresponding to the embodiments. According to the present invention, a spiral blade 5 is provided on the outer periphery of the hollow pile 2 and the center of the spiral blade 5 is provided. The propelling pile 1 in which the fitting hole 6 having a square cross section is formed is connected to the portion, and both the connected piles 1 and 2 are connected.
Inside, a rectangular block 17 that engages with the fitting hole 6 at the tip
The shaft rod 16 provided with the shaft rod 16 is slidably fixed along the shaft rod 16 while having an outer diameter capable of being inscribed in the hollow portion 2a of the hollow pile 2 and having a tapered lower portion on the shaft rod 16. The rotary shaft B provided in the above is inserted, the square block 17 is engaged with the fitting hole 6, and the vibration isolator 18 is loosely inserted, and the vibration isolator 18 is positioned and fixed at the upper end of the hollow pile 2. Then
The rotary shaft B is rotated to apply the rotational force to the lower end portion of the pile to dig the pile.

[Operation] In the method of the present invention, the rotational force of the auger is applied to the propulsion pile 1 via the rotary shaft B. That is, the pile to be sunk is rotated by obtaining a rotational force at its lower end. Therefore, the lower end of the pile, which has the highest resistance due to the cut in the ground by the spiral blade 5 and the earth pressure, is directly rotated. Therefore, almost no torsion moment acts on the entire pile, and the pile is easily and efficiently sunk.

[Examples] Examples of the present invention will be described below with reference to the drawings.

In the method of the present invention, concrete pile A as shown in FIGS. 2 and 3 is used. The concrete pile A consists of a propulsion pile 1 and a hollow pile 2. In the propulsion pile 1, the outer periphery of the concrete pile body 3 is covered with a protective iron plate 4, spiral wings 5 are projected along the outer periphery for one to several turns, and the central portion has a rectangular cross section with a required depth. A fitting hole 6 is formed, and a protective iron plate 7 is formed on the inner surface of the hole 6.
Is being worn. In addition, an end plate 8 having a sufficient thickness is provided on the outer peripheral portion of the base end face, and reinforcing bars 9 and 9 fixed to the end plate 8 are extended into the main body 1.

Since the hollow pile 2 is a commonly used and well-known one, there is no need to particularly describe it. At both ends of the hollow concrete main body 10, annular seat plates 11, 11 and subsequently a reinforcing ring 12, 12 is provided, and in the concrete body 10, both ends are fastened to the seat plates 11, 11 by axial rebars 13, 13 and hoof reinforcements
14 are buried. The propelling pile 1 and the hollow pile 2 are fixed to each other by welding 15 at the outer peripheral edge portions of the end plate 8 and the seat plate 11.

FIG. 4 shows a rotary shaft B used to lay down the concrete pile A. A long rectangular shaft block 16 engages with a fitting hole 6 of the propulsion pile 1 at the tip end thereof. 17 is provided, and the rod 16
In the hollow pile 2, a swing stop body 18 having an outer diameter that allows inward movement in the hollow portion 2a of the hollow pile 2 and a tapered lower portion is inserted through a center hole 19 thereof, and is freely movable along the shaft rod 16. A stop ring 20 that is provided so as to be slidable and that is located between the loosely inserted detent body 18 and the rectangular block 17 and that restricts the lowering of the detent body 18 from extending is the length of the shaft rod 16. It is loosely fitted so that it can be fixed by screws 19 at any position in the direction. An auger joint (not shown) is provided on the upper end of the shaft rod 16.

Next, an example of construction by the method of the present invention will be described. First, the concrete pile A is erected on the ground. At the same time, as shown in FIG. 1, the rotary shaft B is inserted into the pile A, the square block 17 thereof is engaged with the fitting hole 6, and the shaft rod is
16 Connect the auger joint (not shown) at the upper end to the drive shaft (not shown) of the pile digging tower. Further, the anti-slip body 18 is located near the upper end of the hollow pile 2, and the stop ring 20 is fixed by fixing a screw 19 just below the lower end of the anti-slip body 18, and the anti-slip ring 20 supports the anti-slip body 18. . When the rotary shaft B is rotated there, the rotational force is transmitted to the propulsion pile 1, the excavation proceeds by the spiral blades 5, and the pile penetrates into the ground as shown in FIG.

When this concrete pile is to be deeply sunk as a longer one, another hollow concrete pile is welded and adhered to the upper end of the hollow concrete pile A, and at the same time, the rotary shaft B is replenished and the vibration isolator 18 is attached. After moving upward, the pile is positioned at the upper end of the new pile and is supported by the stop ring 20 in the same manner as described above.
Then, the rotating shaft B may be rotated again.

After the pile is completely sunk, the drive shaft and the auger joint may be disengaged and the rotary shaft B may be pulled out upward.

"Effect of the invention" As described above, the present invention is
A propulsion pile having spiral blades protruding from the outer periphery and having a fitting hole with a rectangular cross section at the center is connected, and a rectangular block having a shape corresponding to the fitting hole at the lower end in the connected pile. Inserting a rotating shaft with a square block, fitting the square block into the fitting hole, and applying the rotating shaft's rotating force to the lower part of the pile to perform the sinking, the pile is noise-free and vibration-free in the ground. The pile can be sunk and the rotating force is applied to the lower end of the pile, which has the highest resistance. Therefore, no torsion moment acts on the pile, and the pile can be easily sunk without damaging the pile. Can be done well. In addition, since the anti-sway body is movably provided on the rotating shaft and fixed to the upper end of the pile when the pile is sunk, the rotating shaft does not shake and the centering is accurately performed for smooth construction. In addition, since the upper end of the pile is blocked by the vibration stop body, dirt and sand can be prevented from entering the pile during sinking, and the vibration stop body can be slid and fixed along the rod. Therefore, even when the length of the hollow pile is different or the hollow pile is replenished, the vibration isolator can be freely operated and fixed to the necessary place, and the sunk work can be performed without any hindrance. It has many advantages such as efficient operation.

[Brief description of drawings]

FIG. 1 is a side sectional view showing the state of the concrete pile being sunk by the method of the present invention, FIG. 2 is a side sectional view of the concrete pile used in the present invention, FIG. 3 is the same plan view, and FIG.
The figure is a side sectional view of the rotary shaft. A ... Concrete pile, B ... Rotating shaft 1 ... Propulsion pile, 2 ... Hollow pile 5 ... Spiral blade, 6 ... Fitting hole 16 ... Shaft rod, 17 ... Square block 18 ... Swing stop Body, 20 ... stop ring

Claims (1)

[Claims] 1. A propulsion pile having spiral wings projecting from the outer periphery and a fitting hole having a square cross-section in the center is connected to the tip of the hollow pile, and the tip of each of the connected piles is connected to the tip. A shaft rod provided with a rectangular block that engages with the fitting hole is provided with an anti-vibration body that has an outer diameter that allows inward floating in the hollow portion of the hollow pile and has a tapered lower portion along the shaft rod. Insert the rotary shaft that can be slid and fixed freely, engage the square block with the fitting hole, fix the anti-vibration body at the upper end of the hollow pile, and rotate the rotary shaft. A concrete pile laying method, characterized in that the pile is laid down while applying a rotational force to the lower end of the pile.