JP2011111848A - Sc pile, method for manufacturing the same, and pile head joining method of the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an SC pile, which allows extremely easy joining operation of an anchor reinforcement embedded in the SC pile to a reinforcement of a structure foundation without affecting the quality of a pile body, a method for manufacturing the same, and a pile head joining method of the same. <P>SOLUTION: The SC pile has a cylindrical concrete layer on the inner periphery of a steel pipe 2, and an annular pile end plate 4 provided at a pile head end to cover an end portion of the concrete layer. A plurality of anchor reinforcements 5 are embedded in the concrete layer at the pile head portion at circumferential intervals so as to have a protruding portion 5a protruding out of the pile end plate 4, and a male thread portion is formed on the outer periphery of the protruding portion 5a of the anchor reinforcement 5. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an SC pile, a manufacturing method thereof, and a pile head joining method thereof, and more particularly, to a technique of joining a pile head and a structure foundation by anchor reinforcing bars.

  In recent years, from the viewpoints of short construction period and low cost, the support capacity of ready-made concrete piles has increased, and even with piles of the same diameter compared to conventional embedded pile construction methods, the support capacity has become 2-3 times greater. For this reason, since the horizontal force which one pile bears at the time of an earthquake became larger than before, the example which adopts SC pile (concrete pile with an outer shell steel pipe) which has a large yield strength with a small diameter has increased.

  As one of such SC piles, one in which an anchor reinforcing bar for joining to a structure foundation is embedded in a concrete layer of a pile head in advance is known (see, for example, Patent Document 1). This SC pile with anchor reinforcement has the advantage that the welding work to the steel pipe of the anchor reinforcement after pile construction performed conventionally is unnecessary. However, on the other hand, the anchor reinforcing bars previously embedded in the concrete layer must be exposed, and the pile head processing requires a lot of labor and labor. That is, after the pile construction, the steel pipe of the pile head is cut in the circumferential direction and the axial direction, the crusher is put inside the pile head, the concrete is crushed, and the concrete around the anchor rebar is beaten, and the pile end plate It is necessary to work such as cutting the anchor and reinforcing bar.

  Patent Document 2 discloses an SC pile that eliminates the need for steel pipe cutting work or concrete turning work after pile construction as described above. In this SC pile, anchor reinforcing bars (threaded reinforcing bars) with a coupler nut screwed in advance at the upper end are embedded in the concrete layer, and after the pile construction, the coupler nut is connected to the reinforcing bar on the structure foundation side.

  However, since the coupler nut is embedded in the concrete layer, the one disclosed in Patent Document 2 has a problem that a sufficient concrete cover thickness cannot be obtained at the coupler nut portion. Moreover, there is also a problem that the concrete does not sufficiently wrap around at the time of forming the concrete layer by centrifugal molding, and a high-quality pile body cannot be obtained.

Japanese Patent Laid-Open No. 7-18675 JP-A-5-306527

The present invention has been made based on the technical background as described above, and achieves the following object.
An object of the present invention is to provide an SC pile that can be very easily joined to an anchor reinforcing bar embedded in an SC pile and a structural foundation reinforcing bar, and that does not adversely affect the quality of the pile body, and its manufacture It is in providing the method and its pile head joining method.

The present invention employs the following means in order to achieve the above object.
That is, this invention is a SC pile having a cylindrical concrete layer on the inner periphery of the steel pipe, and having an annular pile end plate covering the end of the concrete layer at the pile head end,
A plurality of anchor reinforcing bars are embedded in the concrete layer of the pile head at intervals in the circumferential direction so as to have a protruding portion protruding from the pile end plate,
The SC pile is characterized in that a male thread portion is formed on the outer periphery of the protruding portion of the anchor reinforcing bar.

  More specifically, the anchor reinforcing bar is integrated by an annular reinforcing bar. A spacer is provided between the anchor reinforcing bar and the steel pipe.

Moreover, this invention is SC pile which has a pile concrete board which has a cylindrical concrete layer in the inner periphery of a steel pipe, and covers the edge part of the said concrete layer in a pile head end part, Comprising: It is in the manufacturing method of SC pile characterized by having.
a. Making pile end plates with multiple holes spaced in the circumferential direction.
b. A plurality of anchor reinforcing bars with male threads formed on at least one end side are arranged at intervals in the circumferential direction so as to form a cylindrical shape as a whole, and these anchor reinforcing bars are integrated by an annular reinforcing bar. Make a kite.
c. The anchor reinforcing bar and the pile end plate are integrated by passing the male thread portion of the anchor reinforcing bar through the hole of the pile end plate.
d. The reinforcing bar rod having the pile end plate is inserted and arranged in a steel pipe, and the pile end plate and the steel pipe are integrated.
e. Placing concrete in a steel pipe so that the reinforcing bar is embedded to form the concrete layer.

  More specifically, a spacer disposed between the anchor rebar and the steel pipe is attached.

Furthermore, this invention is a pile head joining method of the SC pile,
After the SC pile is buried in the ground, a coupler nut is fitted to the projecting portion of the anchor reinforcing bar, and the SC pile is connected to a reinforcing bar of a structure foundation having a male screw portion via the coupler nut. In the pile head joining method.

  According to the present invention, only the anchor rebar is embedded in the concrete layer, and the coupler nut or the like for connecting this to the reinforcing bar of the structure foundation is not embedded. It is possible to obtain a pile body that can wrap around the entire inner circumference of the steel pipe and does not adversely affect the concrete quality. In addition, the anchor rebar and the structural foundation rebar can be connected to each other via a coupler nut fitted to the protruding portion of the anchor rebar, and can be connected to each other via this, so that the pile head joining work can be performed very easily. .

It is a perspective view which shows the pile head of the SC pile by this invention. It is an axial sectional view showing a part of a pile head. It is a front view of a reinforcing bar rod. It is a front view which shows the connection with an anchor reinforcement and the reinforcement of a structure foundation. It is an axial sectional view showing a part of the same.

  Embodiments of the present invention will be described below with reference to the drawings. As shown in FIGS. 1 and 2, the SC pile is a ready-made pile having a cylindrical concrete layer 3 on the inner periphery of the steel pipe 2. The figure shows only the pile head 1 of the SC pile, and an end of the pile head 1 is provided with an annular pile end plate 4 whose outer periphery is welded to the steel pipe 2 and covers the end of the concrete layer 3.

  A plurality of anchor reinforcing bars 5 are embedded in the concrete layer 3 of the pile head 1 at intervals in the circumferential direction. These anchor reinforcing bars 5 are screw reinforcing bars in which a male thread portion is formed on the outer periphery over the entire axial direction, and have a protruding portion 5 a protruding from the pile end plate 4. The anchor reinforcing bars 5 are assembled as main constituent members of the reinforcing bar 6 shown in FIG. 3 and embedded in the concrete layer 3.

  A hoop rebar 7 is arranged on the inner periphery of a group of anchor rebars 5 having a cylindrical shape as a whole, and each anchor rebar 5 is integrated by being fixed to the hoop rebar 7 by a binding wire (not shown). A plurality of spacer reinforcing bars 8 for maintaining a constant distance from the steel pipe 2 are provided at appropriate intervals among these anchor reinforcing bars 5 in the pile axis direction.

The SC pile is manufactured as follows.
(1) Pile end plate The pile end plate 4 is a steel annular plate having an outer diameter equal to the outer diameter of the steel pipe 2. A plurality of holes 9 (see FIGS. 1 and 2) are opened in the pile end plate 4 at intervals in the circumferential direction.
(2) Reinforcing bar 、 As shown in Fig. 3, a plurality of anchor reinforcing bars 5 are arranged on the outer periphery of the hoop reinforcing bar 7 at intervals in the circumferential direction so as to form a cylindrical shape as a whole. Reinforcing bar 6 is formed by fixing these reinforcing bars 5 to the reinforcing bars 7.

(3) Attaching the pile end plate Each anchor rebar 5 is penetrated through the hole 9 of the pile end plate 4 so as to form the protruding portion 5a. Then, by attaching the lock nut 10 shown in FIGS. 4 and 5 to the protruding portion 5a in advance, or by injecting a sealant into the outer peripheral gap of the anchor reinforcing bar 5 in the hole 9, each anchor reinforcing bar 5 and the pile end plate 4 Are fixed and integrated. In addition, a plurality of spacer reinforcing bars 8 are attached to appropriate hoop reinforcing bars 7 by binding wires or welding at intervals in the axial direction.
(4) Reinforcing rod insertion / attachment Reinforcing rod 6 with pile end plate 4 attached is inserted into steel pipe 2 and the outer periphery of pile end plate 4 is fixed to the end of steel pipe 2 by welding.
(5) Molding of the concrete layer The steel pipe 2 is placed in a horizontal state, concrete is placed therein, and the concrete layer 3 is formed by centrifugal molding. When the concrete layer 3 is formed, the anchor reinforcing bar 5 is assembled as the reinforcing bar 6 and the spacer reinforcing bar 8 is disposed between the steel pipe 2 and the anchor reinforcing bar is not shaken by centrifugal force. .

  As described above, the SC pile is manufactured. When the SC pile is transported to the construction site, the protruding portion 5a is provided to protect the protruding portion 5a of the anchor rebar 5 and avoid the danger of the operator. You may make it coat the pile end plate 4 with the polystyrene body which has the hole inserted.

  The SC pile and the structure foundation are joined as follows. 4 and 5 show the SC pile embedded in the ground, and the lower half of the lock nut 10 and the coupler nut 11 are fitted into the protruding portion 5a of the anchor reinforcing bar 5 in order from the pile end plate 4 side. Then, a structural foundation rebar (screw rebar) 12 is fitted to the upper half of the coupler nut 11, and the anchor rebar 5 and the structural foundation rebar 12 are thus connected.

  As described above, according to the present invention, only the anchor reinforcing bar 5 is embedded in the concrete layer 3, and the coupler nut for connecting the reinforcing bar 5 to the reinforcing bar of the structure is not embedded. At the time of forming 3, the cast concrete can be wound around the entire inner circumference of the steel pipe, and a pile body that does not affect the concrete quality can be obtained. Further, the anchor reinforcing bar 5 and the structural foundation reinforcing bar 12 may be connected to each other via the coupler nut 11, and the pile head joining work can be performed very easily.

  The above embodiment is merely an example, and various modifications can be made to the present invention. For example, in the above-described embodiment, the threaded reinforcing bar in which the male thread part is formed over the entire axial direction is used as the anchor reinforcing bar, but the male thread part may be formed only in the protruding part. Further, a spiral reinforcing bar may be used instead of the hoop reinforcing bar.

DESCRIPTION OF SYMBOLS 1 Pile head 2 Steel pipe 3 Concrete layer 4 Pile end plate 5 Anchor reinforcement 5a Protrusion 7 Hoop reinforcement 8 Spacer 9 Hole 10 Lock nut 11 Coupler nut 12 Reinforcement of structure foundation

Claims (6)

SC pile having a cylindrical concrete layer on the inner periphery of the steel pipe, and an annular pile end plate covering the end of the concrete layer at the pile head end,
A plurality of anchor reinforcing bars are embedded in the concrete layer of the pile head at intervals in the circumferential direction so as to have a protruding portion protruding from the pile end plate,
An SC pile characterized in that a male thread portion is formed on the outer periphery of the protruding portion of the anchor reinforcing bar.   The SC pile according to claim 1, wherein the anchor reinforcing bar is integrated by an annular reinforcing bar.   The SC pile according to claim 1 or 2, wherein a spacer is provided between the anchor reinforcing bar and the steel pipe. An SC pile having a cylindrical concrete layer on the inner periphery of a steel pipe and having a pile end plate covering the edge of the concrete layer at the pile head end, and having the following manufacturing process SC pile manufacturing method.
a. Making pile end plates with multiple holes spaced in the circumferential direction.
b. A plurality of anchor reinforcing bars with male threads formed on at least one end side are arranged at intervals in the circumferential direction so as to form a cylindrical shape as a whole, and these anchor reinforcing bars are integrated by an annular reinforcing bar. Make a kite.
c. The anchor reinforcing bar and the pile end plate are integrated by passing the male thread portion of the anchor reinforcing bar through the hole of the pile end plate.
d. The reinforcing bar rod having the pile end plate is inserted and arranged in a steel pipe, and the pile end plate and the steel pipe are integrated.
e. Placing concrete in a steel pipe so that the reinforcing bar is embedded to form the concrete layer.   The SC pile manufacturing method according to claim 4, wherein a spacer disposed between the anchor rebar and the steel pipe is attached. It is a pile head joining method of SC pile according to any one of claims 1 to 3,
After the SC pile is buried in the ground, a coupler nut is fitted to the projecting portion of the anchor reinforcing bar, and the SC pile is connected to a reinforcing bar of a structure foundation having a male screw portion via the coupler nut. Pile head joining method.

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