JPH0799020B2 - Cast-in-place prestressed concrete pile and its construction method - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cast-in-place prestressed concrete pile and its construction method.

[0002]

When using the Related Art place concrete pile as the basis of the structure, it is necessary to consider the horizontal external force or vertical force on Earthquake or the like. Those who increase this horizontal bearing capacity
As a method, increase the diameter of the pile head or
There are ways to increase the muscles. But there were these methods on design and construction, a problem that Kuitai to generate cracks when related to the extent there Rutotomoni the lateral strength, stresses before resistance with the hit設杭interval and the main reinforcement spacing .

Therefore, in recent years , cast- in- place concrete piles have been used.
The head is reinforced with steel pipes, or the entire pile or only the head of the pile
Methods of applying prestress have been considered. This
The pile that applies pre-stress to the entire pile is constructed by inserting a PC steel wire into the reinforcement cage and placing concrete with the reinforcement cage built in the excavation hole. The wire is tensioned and fixed on the pile head.

[0004]

However, the above-mentioned cast-in-place prestressed concrete pile is constructed with a reinforcing bar cage.
After inserting the PC steel wire, this method is PC steel
It is difficult to secure the wire setting position, and PC steel wire
Pressed at the designed position to move when placing concrete
There was a problem that the tress could not be added. In addition,
When the cleat is placed, the outer cover of the PC steel wire is damaged and the steel wire is exposed.
There was also the problem of putting it out. The present invention has been made in view of the above problems, and an object thereof is a PC.
The steel wire can be easily installed in the specified position and
PC steel wire installed at the position moves when pouring concrete
Or, floated or, also is possible to prevent the envelope of the PC steel wire is damaged.

[0005]

In the cast- in- place prestressed concrete pile of the present invention for achieving the above-mentioned object, a cast-in-place concrete pile main body is embedded with a reinforced cage consisting of a main bar and a strip, and A PC steel wire, the rear end of which is tension-fixed at the head of the concrete pile, is inserted into a spiral protection line provided in the lengthwise direction of the inside of the protection wire.
The C steel wire is wound around a plurality of fixing bodies arranged at different positions in a U-turn shape, and each PC steel wire has a core wire and a side wire covered with an inner covering cylinder, and the outer surface of the inner covering cylinder is lubricated. It is characterized by a double coating in which the outer coating cylinder is coated with a chemical agent, and when the reinforcing bar cage with spiral protection bars inside is inserted into the drill hole.
To attach the supporting reinforcement to the upper end of the iron muscle cage, the coercive
Within the protective muscle, U is attached to each of the multiple anchors with different depth positions.
Insert the PC steel wire wound around the turn shape, after securing the supporting rebar to cover the upper portion of the PC steel wire with a protective hose
Place concrete in the drill hole and
Remove the support for the rebar from the rebar cage is Hatsu' the pile head after reduction
Together be, it is to the protection hose construction, characterized in that you remove et or PC steel wire.

[0006]

The PC steel wire has been tensioned the fixing in the head of the working rear end portion child Nkurito pile by inserting into the spiral protection muscles provided in the reinforcing bar cage, the PC steel in striking設時concrete The movement of the wire can be prevented and the wire can be securely installed at a predetermined position, and the PC steel wire can be smoothly inserted. Further, the spiral protection bar can reinforce concrete near the fixing body. Also, P
Since the C steel wire is wound around each of a plurality of fixing bodies arranged at different positions in a U-turn shape, the tensile stress around the fixing body can be dispersed, so that cracking of concrete near the fixing body can be prevented. . Also, PC
The steel wire has a core wire and a side wire covered with an inner coating cylinder, and an outer coating cylinder is coated on the outer surface of the inner coating cylinder with a lubricant to form a double coating. Prevents the core wire and side wires from being exposed due to damage to the cylinder. Also, in the construction method of cast-in-place prestressed concrete piles, U is applied to the anchorages at different depth positions.
By inserting the PC steel wire wound in a turn shape into the protection bar of the rebar cage, the PC steel wire can be smoothly inserted, and after the PC steel wire is inserted into the protection bar, concrete is put in the excavation hole. By pouring, it is possible to prevent the PC steel wire from rising when pouring concrete. In addition, the spiral protection bar can reinforce concrete near the fixing body. Further, by attaching the supporting rebar to the upper end portion of the rebar cage, the upper part of the PC steel wire can be supported by the supporting rebar at the time of placing concrete, and the upper part of the PC steel wire is covered with the protective hose. By placing concrete in the excavation hole, the PC at the time of chipping the pile head after the concrete has hardened
Prevents damage to steel wire.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the cast-in-place prestressed concrete pile and its construction method of the present invention will be described in detail below with reference to the drawings. Figure 1 shows the whole is prestressed
Cross section of a cast-in-place prestressed concrete pile ,
Figure 2 is transverse cross-sectional view of a prestressed concrete pile, Figure 3
4 is a front view of the fixing member inserted in the protection bar, FIG. 4 is a plan view of the latch, FIG. 5 is a side view of the same, FIG. 6 is a plan view of the bearing member , and FIG. 7 is a protection bar in which the fixing member is inserted . Cross-sectional view of the PC, Figure 8 is a PC
It is a transverse sectional view of the steel wire.

In FIG . 1 (1), prestress is applied to the whole.
With cast-in-place prestressed concrete pile 1
The length of the rebar cage 2 consisting of main bars 2a and stirrups 2b
The protective muscles 3 are arranged over the entire length in the
The four fixing members 5 with different depth positions.
The scraped PC steel wire 4 is inserted. The protective muscle 3 are of even that protects the PC steel wire 4 is formed in a spiral shape in 5~10cm pitch, and the fixing member 5 is provided with an insertable diameter. The protective muscle 3 is 5 to 10 cm.
Not limited to pitch, also it is not limited to four also fixing member 5. Moreover, (2) of FIG. 1 is a pile head.
Place pre-stressed toco
Inside the pile 1, which is inside the protective bar 3 arranged on the pile head.
A PC steel wire 4 similar to the above is inserted in the.

[0009] The fixing member 5 as shown in FIG. 3, PC steel wire 4
U-turn around and bundle with different depth positions
Has been. The PC steel wire 4 is wound around the fixing body 5.
It is configured by connecting a cylindrical coupler 7 to the latch 6
ing. A U-shaped groove 6a is formed at the tip of the hook 6.
Is formed, and the flange 8 is integrally formed on the upper portion of the groove 6a.
A guide for hooking the PC steel wire 4 on the flange 8
The grooves 8a are recessed in a radial arrangement (see FIGS. 4 and 5).
See). This guide groove 8a is at least in the same drill hole 1a.
The number of PC steel wires 4 is more than the
In this embodiment, eight are formed.

Therefore, the guide groove 8a has a concave groove 6a.
The PC steel wire 4 wound in a U-turn shape is fitted.

[0011] The rear end portion of the coupler 7, is fitted Bearing bracket 10 as shown in FIG. 6, concave radially arranged before Symbol guide groove 8a as many guide grooves 10a is in said supporting圧金tool 10 Is missing. Therefore, P fixed to each fixing body 5
As shown in FIG. 7, the C steel wire 4 is provided with a guide for each fixing member 5.
Wires 9 are inserted into the id grooves 8a and 10a, respectively.
It is bundled. Therefore, as shown in (1) of FIG.
The flange 8 and the pressure bearing fitting in the uppermost fixing member 5
The PC steel wire 4 is fitted in all of the recessed grooves 8a and 10a of 10
ing.

The PC steel wire 4 is a stranded wire, and the core wire 4a and the side wire 4b of the stranded wire are covered with an inner covering cylinder 4c, respectively, and the outer surface of the inner covering cylinder 4c is covered with a lubricant 4d. So-called double coating in which the outer coating cylinder 4e is coated
Is.

An example of the construction method for the above-mentioned cast-in-place prestressed concrete pile will be described below.
Also not a, drilling borehole 1a by drilling machine 20 with the casing 11 as shown in FIG. Next, as shown in FIG. 10, a plurality of rebar cages 2 are connected on site, but the inner surface
The protective muscles 3 extending in the lengthwise direction are formed at four positions in the.
Next, hoist this rebar cage 2 with a crane and insert it into the excavation hole.
The bottom of the casing so that its bottom edge does not reach the bottom of the hole.
Suspend once at the end and vertically at the upper end of the rebar cage 2.
The supporting reinforcing bar 12 including the reinforcing bar 12a and the reinforcing bar 12b is removed.
Attach

Next, in each protection bar 3 of the rebar cage 2, the depth position is set.
PC steel wire wrapped around the fixing body 5 with different placement
4 is inserted, and a reinforcing bar 12 for supporting the PC steel wire 4 is inserted.
Is covered with a protective hose 13 to support it
Fix it to the reinforcing bar 12 with a numbered wire (see FIG. 12). This protection
The upper and lower parts inside the hose 13 are made of urethane foam 13a.
It is covered with. However, this is urethane foam 13a
However, it may be covered with other materials (see FIG. 13).
See).

Next, in this way , the PC steel wire 4 is placed in the protection bar 3.
Ke but the rebar cage 2 that has been inserted, and lifting in again crane
It is removed from the housing and dropped into the excavation hole 1a (see FIG. 14). Then, as shown in FIG. 15, concrete 16 is placed in the excavation hole 1a by the tremie pipe 15. At this time, the PC steel wire 4 is inserted into the protection bar 3,
One double coating a is for upper-out floating <br/> by pouring concrete 16 rear, prevent the exposure of the stranded wire according to the envelope of the damage.

16 (1) and 16 (2).
As such, When the concrete 16 is cured, and removing the support for rebar 12 Hatsu' the pile head from the top of the rebar cage 2 door
Also, remove the protection hose 13 from the PC steel wire 4. Next
, As shown in (3) in the figure, when the reinforcement of the foundation DOO
After filling the cell <br/> placement milk and rust-preventive oil and the like therein monitor PC steel wire 4 fitted a sleeve 17, a concrete foundation 18 for pouring.

Then, the basic concrete 18 is hardened.
Once you tension fixing PC steel wire 4 in the foundation 19 the top. this
With cast-in-place prestressed concrete piles 1 impart prestressed is constructed by, 該杭1
There is connected to the base 19. Therefore, the bending moment due to horizontal force such as an earthquake may cause the pile head to collapse and pull out.
The pile slab can be prevented from cracking and the foundation slab
You can also connect to the pile.

【The invention's effect】

The rear end child Nkurito pile of tension The fixed PC steel wire in the head, by inserting into the spiral protection muscles provided in the reinforcing bar cage, the PC steel in striking設時concrete The movement of the wire can be prevented and the wire can be securely installed at a predetermined position, and the PC steel wire can be smoothly inserted. Further, the spiral protection bar can reinforce concrete near the fixing body.

Since the PC steel wire is wound around each of a plurality of fixing bodies arranged at different positions in a U-turn shape, the tensile stress around the fixing body can be dispersed, so that the concrete strength in the vicinity of the fixing body can be improved. Prevents cracking.

The PC steel wire has a core wire and a side wire covered with an inner coating cylinder, and an outer coating cylinder is coated on the outer surface of the inner coating cylinder with a lubricant to form a double coating. It is possible to prevent the core wire and the side wire from being exposed due to breakage of the outer covering cylinder at the time.

In the construction method for cast-in-place prestressed concrete piles, PC steel wires wound in U-turns around anchorages having different depth positions were inserted into the protection bars of the rebar cage to insert the PC steel wires. In addition, the PC steel wire can be made smooth, and the PC steel wire can be prevented from being lifted up when the concrete is placed by placing the concrete in the excavation hole after inserting the PC steel wire into the protection bar. In addition, the spiral protection bar can reinforce concrete near the fixing body. Furthermore, by attaching a supporting rebar to the upper end of the rebar cage, the upper part of the PC steel wire can be supported by the supporting rebar at the time of placing concrete, and the upper part of the PC steel wire is covered with a protective hose. By placing the concrete in the excavation hole, it is possible to prevent the PC steel wire from being damaged when the pile head is chipped after the concrete is hardened.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a cast-in-place prestressed concrete pile in which prestressing is applied to the entire pile, and FIG. 1B is a cross-sectional view of a cast-in-place prestressed concrete pile in which a pile head is prestressed.

[Figure 2] Crossing of cast-in-place prestressed concrete piles
It is a side view.

FIG. 3 is a front view of a fixing member inserted in a protective muscle.

FIG. 4 is a plan view of a latch.

FIG. 5 is a side view of the same.

FIG. 6 is a plan view of a bearing member.

7 (1) is a sectional view taken along the line AA of FIG. 3, and (2) is the same drawing.
BB line sectional view of (3) is a CC line sectional view of the same figure,
(4) is the DD sectional view taken on the line of the same figure.

FIG. 8 is an enlarged cross-sectional view of a PC steel wire.

FIG. 9 is a cross-sectional view of a drill hole.

FIG. 10 is a cross-sectional view in which a rebar cage is suspended in a casing .

FIG. 11 is a perspective view of a supporting reinforcing bar.

FIG. 12 is a cross-sectional view in which a PC steel wire is inserted into a protection bar.

FIG. 13 is a cross-sectional view of a protective hose attached to a PC steel wire .

FIG. 14 is a cross-sectional view in which a reinforcing bar cage is installed.

FIG. 15 is a cross-sectional view in which concrete is placed in an excavation hole.

FIG. 16 (1) is a sectional view of a stilt head in which a protective hose is inserted into a PC steel wire, (2) is a sectional view of a stilt head in which a protective hose is removed from the PC steel wire, and (3) is a PC steel wire. FIG. 3 is a cross-sectional view of a stigma that is strained and fixed on the basis of FIG.

[Explanation of symbols]

 1 Cast-in-place prestressed concrete pile 1a Excavation hole 2 Reinforcing bar cage 3 Protective bar 4 PC steel wire 5 Anchoring body

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Ikumasa Hara 1-18-50 Mihara, Asaka-shi, Saitama Prefecture (72) Inventor Keizo Tanabe 1889-2 Magome, Hasuda-shi, Saitama (56) Reference JP-A-57-21622 (JP, A) JP 48-2908 (JP, A) JP 61-10622 (JP, A) JP 61-31523 (JP, A) JP 47-29244 (JP, B1) JP JP-B 47-51161 (JP, B1) JP-B 53-41893 (JP, B1) JP-B 56-23492 (JP, B2) JP-B 61-47930 (JP, B2)

Claims (2)

[Claims] 1. A reinforcing bar cage comprising a main reinforcement <br/> girdle muscular and in-place concrete pile in the body is buried, iron muscle basket length of the inner
Insert the PC steel wire whose rear end is tension-fixed at the head of the concrete pile into the spiral protection line provided in the direction.
The PC steel wire is wound around a plurality of fixing bodies arranged at different positions in a U-turn shape, and each PC steel wire has a core wire and a side wire covered with an inner covering cylinder, A cast-in-place prestressed concrete pile, characterized in that it is a double coating with an outer coating cylinder coated on the outer surface with a lubricant. 2. A reinforcing bar cage having spiral-shaped protective bars inside is inserted into the excavation hole, and a supporting reinforcing bar is attached to the upper end of the reinforcing bar cage , and a depth position is provided in the protective bars.
Insert the different fixing bodies PC steel wire wound around the U-turn shape respectively of location, Conch drilling hole after securing the supporting rebar upper part covered with a protective hose of the PC steel wire
REITs were Da設, the supporting reinforcing bar Hatsu' the pile head after hardening of the concrete with detached from reinforcing bar cage, cast-in-place prestressed concrete piles, characterized in that you remove the protection hose et or PC steel wire Construction method.