JP2003232035A - Base-enlarged plate for rotary buried steel pipe pile, and method for mounting the base-enlarged plate on rotary buried steel pipe pile - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a base-enlarged plate for a rotary buried steel pipe pile, which is excellent in storage and transportation and can be easily mounted, and a method for mounting the base-enlarged plate on the rotary buried steel pipe pile. <P>SOLUTION: This base-enlarged plate 1 is composed of: a base body plate 2 in which a fitting opening 3 is opened; a plurality of fan-shaped earth removing openings 4 which are formed by notching an outer peripheral edge 20 of the plate 20; an upper blade 42 which is formed by being bent in such a manner as to be inclined upward with respect to the direction of anti-rotation from an edge 40, on the side of the direction of rotation, of the opening 4; and a lower blade 43 which is formed by being bent at a sweepback angle in the direction of the rotation in such a manner as to be inclined downward in the direction of the rotation from an edge 41 on the side of the direction of the anti-direction. A rib 5 is arranged in the direction of rotation of an under surface of the plate 2; the fitting opening 3 is formed in such an oval shape that its minor axis is smaller in diameter than the steel pipe pile 6 for mounting; and notched openings 30, through which a blade 61 of the pile 6 is passed, are formed on both sides of its major axis. In the mounting of the plate 1 on the pile 6, the side of a tip of the pile 6 is impacted from the fitting opening 3 and notched openings 30 of the plate 1 which is placed on ground; the pile 6 is rotated around an axis; and its tip part 60 and the fitting opening 3 can generate friction with each other so as to be fixed together. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bottom pile for a foundation pile arranged near the tip of a foundation pile used for reinforcing the ground portion that serves as the foundation of a building or civil engineering structure.

[0002]

2. Description of the Related Art In the construction of construction and civil engineering structures, foundation piles made of prestressed concrete, steel pipes, etc. are buried to reinforce the foundation in order to increase the bearing capacity of the foundation portion of the building. Various construction was done.

For the purpose of burying foundation piles, a so-called impact type was mainly used, but in recent years, in consideration of environmental damage, a rotary burying type with no discharge soil, low vibration, low noise and high bearing capacity. It has been changed to steel pipe piles (or rotary penetration type). The construction of these rotary buried steel pipe piles was mounted on a hydraulic motor for earth auger, etc., and buried in the ground by axial rotation and pressing force.

The structure of this rotary buried type steel pipe pile is, for example, as shown in FIG. 9A, a spiral blade P1a (screw) is provided on the outer peripheral surface on the lower end side of the steel pipe pile body, and the ground is rotated by axial rotation. To the bottom of the drilling blade P1b
The earth and sand are excavated and softened by the spiral blade P1a.
By digging into the unexcavated earth and sand on the side surface of the main body of the steel pipe pile to rotate and bury it in the ground by using the proof strength of the soil as a reaction force (hereinafter, referred to as "spiral blade pile P1"). A structure similar to this example is disclosed in JP-A-7-173832.

As another example, as shown in FIG. 9B, an inclined blade P2a is attached to the tip portion or the outer peripheral surface of the pile main body so as to be eccentric from the axial center of the pile main body, and the inclined blade P2a is attached.
There is also a structure (hereinafter, referred to as "blade pile P2") in which the ground is excavated with and the excavated soil is discharged upward from a gap generated by the arrangement of the inclined blades P2a having an inclination angle, and is buried underground. It was A structure similar to this example is disclosed in
000-170159.

[0006]

However, in the above-mentioned spiral blade pile P1, the frictional resistance force generated from the unexcavated earth and sand on the side surface of the steel pipe pile body, the entire side surface of the steel pipe pile body, and the entire spiral surface of the spiral blade P1a. However, there is a drawback in that it increases in proportion to the excavation depth, and that its construction requires a large pressing force and a large torque and its power energy to rotate the steel pipe pile. For this reason, construction on hard ground having a high N value (one of the indexes showing the strength of the ground) becomes difficult, resulting in an increase in construction cost. Moreover,
Since the spiral blade P1a is welded and fixed to the side surface of the steel pipe pile, not only the steel pipe pile itself becomes high in cost due to its manufacturing difficulty, but also the spiral blade P1a increases the lateral storage area, so that storage and construction are possible. Handling during transportation to the site was inconvenient.

In the blade pile P2 described above, the inclined blades P2a arranged at a predetermined inclination angle provide high supporting force to the ground similarly to the bottom plate, but the lower end side of the inclined blades P2a serves as an excavating blade. Therefore, the penetrability was poor and high torque was required, and the so-called consolidation effect was low. Further, since the blade is eccentrically attached to the pile body, the blade attachment portion of the pile body is processed and welding is performed. For this reason,
As with the spiral wing pile P1, its production is expensive and its handling is inconvenient during storage and transportation.

[0008]

[Purpose] Therefore, the present invention has been made by paying attention to such a problem, and has an efficient penetrability and a compacting action while having a high bearing capacity to the ground, and a method of mounting the steel pipe pile. (EN) Provided is a bottom plate for a rotary buried steel pipe pile, which is simple and excellent in handleability such as storage and transportation, and a method of mounting the bottom plate to the rotary buried steel pipe pile.

[0009]

In order to achieve the above object, a bottom plate for a rotary buried steel pipe pile according to the present invention is constructed as follows. That is, in a flange-shaped bottom plate integrated into the vicinity of the tip of a steel pipe pile to be rotationally buried, a plate-shaped base plate (2) having a fitting port (3) opened in the center and an outer peripheral edge of the base plate (2). (20) An earth discharging port (4) having one or a plurality of cut out portions, and an inclined direction from a rotation direction side edge (40) of the earth discharging port (4) toward an upper side in a counter rotation direction. The upper blade (42) and the edge (41) of the soil discharge port (4) on the side opposite to the rotation direction are inclined downward in the rotation direction,
And the lower blade (4
It is characterized by consisting of 3) and.

Further, in forming the upper blade (42) and the lower blade (43), the edges (40, 41) of the soil discharging port (4) formed on the base plate (2) are bent in a predetermined direction. It is characterized by that.

Further, in the formation of the soil discharge port (4), a straight line passing from the peripheral edge (20) to the radial line of the base plate (2) is removed in a fan shape.

Furthermore, a plate-like rib (5) having a surface along the rotational direction on the upper surface and / or the lower surface of the base plate (2).
It is characterized by having been erected.

In addition, a rotary buried steel pipe pile (where the tip portion (60) of the pile has a conical shape and a blade (61) having a predetermined rake angle is arranged along the generatrix of the conical shape ( In the fitting port (3) for fitting 6), the minor diameter is set to be smaller than the diameter of the rotary buried steel pipe pile (6) to form an elliptical shape, and the blade (6
It is characterized in that a cutout (30) having a size through which 1) can pass is formed.

Next, the method of attaching the bottom expanding plate constructed as described above to the rotary buried steel pipe pile is as follows. The bottom plate (1) is placed on the ground for embedding, and a blade (61) having a conical tip end (60) and a predetermined rake angle is placed along the conical generatrix. After inserting the installed rotary buried steel pipe pile (6) into the fitting port (3) and the notch (30) from the tip, the rotary buried steel pipe pile (6) is axially rotated to tip (60). ) And the fitting port (3) are frictionally fixed to each other, whereby the bottom expanding plate (1) and the rotary buried steel pipe pile (6) are integrated.

The reference numerals in parentheses described in the claims and the means for solving the problems mentioned above are the reference numerals attached to the drawings for the purpose of facilitating the understanding of the constitution of the invention. Of course, it is not limited to the form in the drawing.

[0016]

By adopting the constitutions of claims 1 to 5, the bottom expanding plate can be properly attached to the rotary buried steel pipe pile, and after the attachment, it is integrated with the steel pipe pile and is rotationally buried in the ground. . Further, during rotary embedding, the excavated soil softened by the lower blade is discharged to the upper side and the side of the bottom expanding plate from the outlet of the bottom expanding plate, and is discharged to the periphery of the side by the upper blade of the bottom expanding plate.

By adopting the method of claim 6, the pile starts to penetrate into the ground due to axial rotation, the position of the bottom expanding plate with respect to the pile rises, and the conical portion at the tip of the pile frictions with the minor diameter side of the fitting port. It will be fixed and integrated, and will be embedded in the ground by rotation.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Specific embodiments of the bottom plate 1 for a rotary buried steel pipe pile according to the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a perspective view showing the overall appearance of the bottom expanding plate of this embodiment, FIG. 2 is a partially enlarged perspective view showing the earth discharging port of the bottom expanding plate of this embodiment, and FIG. It is an expanded perspective view which shows the modification (A) of the rib of the bottom expansion plate of this embodiment, and (B), FIG. 4 is explanatory drawing which shows the formation method of the bottom expansion plate of this embodiment, and FIG. It is explanatory drawing which shows the attachment method of the rotary buried steel pipe pile and bottom expansion plate of this embodiment, and FIG. 6 shows the working state in which the rotary buried steel pipe pile and bottom expansion plate of this embodiment are integrally rotatably buried in the ground. It is a partially notched perspective view shown.

In the description of the present embodiment, the direction of rotation (arrow a) for penetrating the ground is the "rotational direction" of the rotary buried steel pipe pile (hereinafter abbreviated as "steel pipe pile"). The direction is defined as "counter-rotation direction".

The steel pipe pile 6 to which the bottom plate 1 used in this embodiment is attached is a conical portion 6 in which the tip of the pile has a conical shape.
The blade 61 having a zero angle and a predetermined rake angle is arranged along the generatrix of the conical portion 60. Regarding this, the applicant of the present invention first issued the patent 289
Since the configuration is the same as that disclosed and obtained as a patent of No. 3443, the detailed description of the configuration is omitted.

As shown in FIG. 1, the bottom expanding plate 1 of this embodiment is mainly composed of a plate-shaped base plate 2 having an outer diameter of about 2 to 3 times the outer diameter of the steel pipe pile 6, and its center. Part, the fitting port 3, and the line around the discharge port 4, the upper blade 42, the lower blade 43,
And ribs 5 are formed.

First, the fitting port 3 has a substantially elliptical opening shape opened in the center of the base plate 2, and the minor diameter of the fitting port 3 is smaller than the diameter of the steel pipe pile 6. Further, a rectangular cutout 30 is formed on the opposite edge of the fitting port 3 on the long diameter side so that the blade 61 of the steel pipe pile 6 can pass therethrough.

As shown in FIGS. 1 and 2, the earth discharging port 4 passes on both sides of the fitting port 3 on the shorter diameter side and passes from the peripheral edge 20 of the base plate 2 to the shorter diameter line of the fitting port 3. A straight line is deleted into a substantially fan shape having a predetermined angle (α + β), and further, a parallel movement is performed by a predetermined distance λ toward the side opposite to the rotation direction to form a notched shape.

The upper blade 42 is attached with a predetermined inclination angle extending upward from the edge 40 on the rotation direction side of the soil discharging port 4 in the opposite rotation direction. The lower blade 43 is attached to the edge 41 on the side opposite to the rotation direction of the soil discharge port 4 with a predetermined inclination angle extending downward in the direction of rotation.

Finally, the ribs 5 are arranged on the opposite peripheral edges 20 on the major axis side of the fitting port 3 and are bent to form a plate-like body extending to the lower surface side of the base plate 2. The arrangement of the ribs 5 is for the purpose of improving the rigidity of the bottom plate 1 and is not limited to this form, but may be bent to the upper surface side (not shown), and FIG. As shown in FIG. 3, the corners on the rotation direction side of the ribs 50 may be made to have an acute angle so as to function as the digging blade 50a. Furthermore, as shown in FIG. 3B, the upper surface on the inner side of the peripheral edge 20 of the base plate 2 or The rib 51 may be arranged by welding on the lower surface.

In this embodiment, the upper blade 42,
The lower blade 43 and the rib 5 are formed as an integral molding in which a part of the base plate 2 is bent (bent) in consideration of the material yield. The processing is performed, for example, as shown in FIG. 4A, a reference point 44 on the extension line of the minor diameter line in the fitting port 3.
Toward, the edge is cut at a predetermined receding angle β with respect to the minor axis line by gas fusing or the like (cutting line b). Next, the trajectory of the reference point is similarly cut when the b cutting line is translated in the direction opposite to the rotation direction by a predetermined distance λ (c cutting line).

Then, as shown in FIG. 4 (B), the upper blade 4
2 is formed by bending the section on the rotational direction side separated by the cutting line b upward with the reference point 44 as the apex and at a predetermined advance angle α with respect to the minor axis line (arrow d). The lower blade 43 is formed by bending the reference point 44 downward along the cutting line c with the same receding angle β as that of the cutting line b (arrow e).

Further, the ribs 5 arranged so as to face the base plate 2 are formed by leaving the peripheral edge 20 on the major axis side as a rectangular extending piece in advance to take the material of the base plate 2, and thereafter, this portion. Is bent downward (arrow f).

[0030]

Next, a method of attaching the bottom expanding plate constructed as described above to the steel pipe pile will be described. First,
The bottom expansion plate 1 is placed on the ground at the burying point of the steel pipe pile 6. Then, as shown in FIG. 5, while vertically holding the steel pipe pile 6 gripped through the rotary penetration device such as the hydraulic excavator S equipped with the hydraulic motor M, the fitting port 3 and the cutout port of the bottom plate 1 are provided. The tip end side of the steel pipe pile and the blade 61 are fitted into 30.

Next, the hydraulic motor M is activated to activate the steel pipe pile 6
When the shaft is rotated while being pressed against the ground, the steel pipe pile 6 starts to be buried while excavating the ground. At this time, the blade 61
Since the bottom plate 1 rotates with the steel pipe pile 6 on the ground because it is engaged with the cutout port 30, the blade 61 passes through the cutout port 30 and comes off as the steel pipe pile 6 goes into the ground. hand,
The elliptical minor axis side of the fitting port 3 and the conical portion 60 of the steel pipe pile 6 are frictionally fixed. After that, as shown in FIG. 6, the bottom expanding plate 1 rotates together with the steel pipe pile 6, and the lower blade 43 on which the pressing force acts is also excavated and rotationally buried in the ground.

At the time of the above-mentioned rotary burying, the bottom expanding plate 1 acts on the ground together with the steel pipe pile 6 as follows. That is, the excavated earth and sand excavated by the blade 61 of the steel pipe pile 6 is sent upward and sideways along the blade 61, and the soil discharge port 4 in which the upper blade 42 and the lower blade 43 of the bottom plate 1 are arranged.
With the configuration, excavated soil is guided to the upper rear part. Also,
Gravels and the like having a size that cannot pass through the soil discharge port 4 are positively pushed to the side of the bottom plate 1 because the lower blade 43 is attached at a receding angle β with respect to the rotation direction. Furthermore, in a plan view, the upper blade 42 and the lower blade 43 are overlapped so as to close the soil discharge port 4, whereby the steel pipe pile 6 secures a sufficient vertical drag force against the ground.

[0033]

[Possibilities of Other Embodiments] In order to achieve the object of the present invention, the embodiments can be modified as follows. First, as shown in FIG. 7, when the steel pipe pile 7 has three blades 70, the shape of the fitting port 3 is a substantially equilateral triangle with each side projecting inward, and 3
You may form the notch 30 of a location. Similarly, when the steel pipe pile has four blades, the shape of the fitting port 3 is made into a substantially square shape with each side projecting inward, and four notch ports 30 are provided correspondingly. May be formed (not shown). It should be noted that the arrangement and the number of the soil discharge ports 4 and the ribs 5 of the bottom plate 1 when using these steel pipe piles 7 are not limited to the above-described embodiment but are appropriate.

Furthermore, when the steel pipe pile 8 is a square pipe, as shown in FIG. 8, the fitting port 3 is formed in a rectangular shape that fits the square steel pipe pile 8, and the bottom plate 1 has a rectangular shape. You may make it arrange | position the locking means with the steel pipe pile 8, such as a bar 80 shown inside.

[0035]

With the above structure, the bottom plate according to the present invention is
Emission-free soil, low vibration, low noise, and high bearing capacity can be secured, and the expansion plate can be easily attached to the steel pipe pile at the construction site without impairing the same effects as the conventional steel pipe pile with a expansion plate. In addition, it is excellent in handleability such as storage and transportation, and further has an excellent effect that the manufacturing cost can be reduced.

[Brief description of drawings]

FIG. 1 is a perspective view showing an overall appearance of a bottom expanding plate of the present embodiment example.

FIG. 2 is a partially enlarged perspective view showing an earth discharging port of the bottom expanding plate of the embodiment.

FIG. 3 is an enlarged perspective view showing modifications (A) and (B) of the ribs of the bottom expanding plate of the embodiment.

FIG. 4 is explanatory views (A) and (B) showing a method for forming a bottom plate of the present embodiment.

FIG. 5 is an explanatory view showing a method of mounting the rotary buried steel pipe pile and the bottom expanding plate of the embodiment.

FIG. 6 is a partially cutaway perspective view showing a working state in which the rotary buried steel pipe pile and the bottom expanding plate of the present embodiment are integrated and rotary buried in the ground.

FIG. 7 is a perspective view showing a rotary buried steel pipe pile and a bottom plate according to another embodiment.

FIG. 8 is a perspective view showing a rotary buried steel pipe pile and a bottom plate according to another embodiment.

FIG. 9 is a perspective view showing a conventional rotary buried steel pipe pile.

[Explanation of symbols]

1 Bottom plate 2 Base plate 20 rim 3 Mating port 30 Notch 4 soil outlet 40 edge (rotation direction side) 41 Edge (counter rotation direction side) 42 Upper blade 43 Lower blade 44 reference point 5 ribs 50 ribs (modification) 50a drilling blade 51 ribs (top layout) 6 Steel pipe pile (conical type) 60 cone 61 blade 7 Steel pipe pile (3 blades) 70 blade 8 Steel pipe pile (square pipe) 80 bar P1 spiral blade pile (conventional example) P1a spiral wing P1b drilling blade P2 wing pile (conventional example) P2a inclined wing M hydraulic motor S hydraulic excavator

Claims (6)

[Claims] 1. A flange-shaped bottom plate integrated into the vicinity of the tip of a steel pipe pile to be rotationally buried, wherein a plate-shaped base plate (2) having a fitting port (3) opened in the center thereof.
And an earth removal port (4) in which one or more locations of the outer peripheral edge (20) of the base plate (2) are cut out, and an anti-rotation from the rotation direction side edge (40) of the earth removal port (4) The upper blade (42) inclined upward in the direction of rotation, and the edge (41) of the soil discharge port (4) on the side opposite to the rotation direction, which is inclined downward in the direction of rotation and A bottom plate (43) for a rotating buried steel pipe pile, comprising: a lower blade (43) arranged with a receding angle. 2. In forming the upper blade (42) and the lower blade (43), the edges (40, 4) of the soil discharge port (4) formed in the base plate (2).
The bottom plate for a rotary buried steel pipe pile according to claim 1, wherein the bottom plate is formed by bending 1) in a predetermined direction. 3. The excavation opening (4) is characterized in that the straight line passing from the peripheral edge (20) to the radial line of the base plate (2) is removed in a fan shape to form the excavation opening (4). Expanded bottom plate for the rotary buried steel pipe pile described. 4. A plate-shaped rib (5) having a surface extending along the rotational direction is provided upright on the upper surface and / or the lower surface of the base plate (2). Expanded bottom plate for the rotary buried steel pipe pile described. 5. A rotary buried steel pipe pile (6) in which a tip (60) of the pile has a conical shape, and blades (61) having a predetermined rake angle are arranged along the generatrix of the conical shape. In the fitting port (3) when fitting the), a short diameter is formed into an elliptical shape with a diameter smaller than the diameter of the rotary buried steel pipe pile (6), and a blade (61) is formed on the inner peripheral edge when the tip is inserted. 5. A bottom plate for a rotary buried steel pipe pile according to claim 1, 2, 3, or 4, characterized in that a cutout opening (30) having a size that allows passage is formed. 6. A bottom plate (1) for a rotary buried steel pipe pile according to claim 1, 2, 3, 4 or 5 is placed on the ground for burial construction, and the tip portion (60) of the pile has a conical shape. A rotary buried steel pipe pile (6), in which a blade (61) having none and a predetermined rake angle is arranged along the conical generatrix, is fitted with a fitting port (3) and a notch port (30) from the tip. Then, the rotary buried steel pipe pile (6) is axially rotated to frictionally fix the tip portion (60) and the fitting opening (3), whereby the bottom expanding plate (1).
A method for mounting a bottom plate to a rotary buried steel pipe pile, characterized in that the rotary buried steel pipe pile (6) is integrated.