JP2015151842A - Pile head treatment method and pile head burial bag used for pile head treatment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the work efficiency for pile head treatment when constructing a cast-in-place concrete pile.SOLUTION: By fixing annularly a pile head treatment bag of a columnar shape inflated with the air along a hoop reinforcement in a gap between the hoop reinforcement at the pile head and a holding reinforcement on the inner side of the hoop reinforcement and then casting concrete, weld overlay around an inner side of a reinforcement cage may be removed when the pile head treatment bag is removed. This eliminates the need to crush the weld overlay around an inner side of a reinforcement cage with a drill or other equipment, which has caused a decline in the work efficiency for pile head treatment, thereby enhances the work efficiency for pile head treatment.

Description

  The present invention relates to a pile head processing method for cast-in-place concrete piles and a pile head burying bag used in the pile head processing method.

  As a method of constructing a reinforced concrete pile that supports the foundation of a building, after excavating the ground where the pile is to be built to form a drill hole, a reinforcing bar is installed in the drill hole and the concrete is The cast-in-place concrete pile construction method is used in which the pile is constructed by placing.

  In the cast-in-place concrete pile method, when excavating the excavation hole, a stabilizing liquid for preventing and protecting the excavation hole wall is injected into the excavation hole. As the stabilizing liquid, muddy water mainly composed of bentonite is often used, and a liquid in which an organic polymer, a liquid dispersant, a mud prevention material, etc. are blended in addition to bentonite can be used.

  After forming the excavation hole, a reinforcing bar rod comprising a pile main bar arranged in the depth direction of the hole in the excavation hole and an annular hoop bar connecting the pile main bar in the circumferential direction for the purpose of maintaining the strength of the concrete pile. It will be installed in the excavation hole, and concrete will be placed after the reinforcing bar is installed.

  When the concrete is placed, the stabilizing liquid is in the excavation hole. Since concrete is cast while removing the stabilizing liquid using a Tremy tube, etc., the pile head constituting the upper end of the placed concrete is formed by a mixture of concrete and stabilizing liquid. There will be a part. The mixture containing a stabilizing liquid as an impurity often has properties that are not suitable as a pile, such as a lower strength than a portion made only of concrete.

  For this reason, in the prior art, an extra portion of concrete is placed on the pile head that is considered to constitute the mixture. The pile head was removed with a drill.

JP 2001-288743 A

  However, the mixture constituting the surplus is also a hard object similar to concrete, and a large amount of labor is required for an operator to crush the surplus with a drill or the like. Further, as described above, the cast-in-place concrete pile is embedded with a reinforcing bar made of a pile main bar arranged in the depth direction of the hole and an annular hoop bar connecting the pile main bar in the circumferential direction. Has been. Therefore, it is necessary to work so as not to damage the pile main reinforcing bar etc. especially during the work of crushing the surplus in the vicinity of the rebar rod, which causes the work speed to decrease and the efficiency of the pile head processing to decrease. It was.

  Then, the pile head processing method which concerns on this invention as a means to solve the said subject is the cyclic | annular form which connects the pile main reinforcement arrange | positioned in the depth direction of a hole in the excavation hole provided in the ground, and a pile main reinforcement in the circumferential direction. A pile head processing method for removing a pile head pile of a cast-in-place concrete pile formed by installing a reinforcing bar rod composed of a hoop bar and placing concrete in the excavation hole after the reinforcing bar rod is installed. In the inner peripheral surface side of the upper end portion of the reinforcing bar rod, a holding reinforcing bar that forms a gap portion with the hoop bar along the circumferential direction is provided, and the reinforcing bar is formed in the excavation hole. A bag-like main body, which is formed of a flexible and thick resin material having a hollow inside, and an air inlet provided at the tip of the bag-like main body, is filled with air. And a long diameter that is sufficiently larger than the gap A pile head embedded bag that becomes a long belt shape that is a long flat body that can easily pass through the gap when air is discharged, and has a tip portion in a long belt state. It is inserted into the gap so as to face upward, filled with air from the air inlet, and the pile head embedded bag is formed into a columnar shape, and the outer surface of the pile head embedded bag is connected to the hoop of the reinforcing bar and the presser By fixing the pile head embedded bag between the reinforcing bar hoop and the holding bar by sandwiching it with the reinforcing bar, and repeatedly performing the fixing operation along the circumferential direction of the reinforcing bar A plurality of pile head buried bags are annularly installed along the inner peripheral surface of the reinforcing bar, and the concrete is placed to a position where the air inlet can be exposed to the excavation hole, The bag-shaped body of the pile head buried bag was laid Embedded in the pile head of the concrete, and after the concrete is hardened, by opening the air inlet, the air is exhausted from the hollow portion of the pile head embedded bag and the bag-shaped body is contracted to form a long band, The bag-shaped main body in the form of a long belt is gripped, the plurality of pile head buried bags are extracted from the pile head, and the remaining surplus is removed.

  In addition, an outer edge holding reinforcing bar that forms an outer edge clearance portion between the upper end portion of the reinforcing bar and the hoop bar along the circumferential direction is provided on the outer peripheral surface side, and the reinforcing bar bar is formed in the excavation hole. After the fixing work, before the fixing work or after the fixing work, the pile head embedded bag is inserted into the outer edge gap part so that the tip part is upward in the state of the long band, and the air inlet The pile head embedded bag is formed into a columnar shape, and the outer surface of the pile head embedded bag is sandwiched between the hoop bar of the reinforcing bar rod and the outer edge holding reinforcing bar, and the hoop bar of the reinforcing bar rod An outer edge fixing operation for fixing the pile head burying bag between outer edge holding reinforcing bars is performed, and the outer edge fixing operation is repeatedly performed along a circumferential direction of the reinforcing bar rod, whereby a plurality of pile head embedded bags are Install in a ring along the outer peripheral surface of It may be with.

  Furthermore, the pile head embedding bag according to the present invention is a reinforcing bar comprising a pile main bar arranged in a depth direction of a hole in an excavation hole provided in the ground and an annular hoop bar connecting the pile main bars in the circumferential direction. On the inner peripheral surface side of the upper end portion of the reed bar installed in the excavation hole and the barb, a holding bar provided by forming a gap portion between the hoop bar along the circumferential direction is installed. A pile head burying bag used for a pile head processing method for removing the pile head pile of a cast-in-place concrete pile formed by placing concrete in the excavation hole after the rebar is installed; A bag-like main body made of a flexible and thick resin material having a hollow portion inside, and an air inlet provided at the tip of the bag-like main body, and when the air is filled, the gap portion It is a long column with a sufficiently large diameter A long strip shape, which is a long flat body that can easily pass through the gap when air is discharged, and the tip portion is directed upward in the state of the long strip shape. A plurality of rings are inserted annularly along the inner peripheral surface of the reinforcing bar rod into the gap portion, and are filled with air from the air inlet port to form a columnar shape. By being sandwiched between the presser reinforcing bars, the tip part is directed upward to the concrete pile head that is fixed between the hoop bar and the presser bar of the reinforcing bar and is placed against the excavation hole. In addition, the air inlet provided at the tip is embedded to a position where it can be exposed, and after the concrete is hardened, the air inlet is opened to exhaust air from the hollow portion and the bag-like body Contracted to a long belt Is a condition characterized by excess prime to be the pile head withdrawn from the pile head the bag-like body long strip form is gripped is formed.

  The presser rebar is attached to the rebar so as to form a gap between the hoop and the facing part, and is preferably formed by fixing the open ends of the U-shaped rebar to the rebar. is there. At this time, it is preferable that a plurality of U-shaped holding reinforcing bars are installed in an annular shape along the inner peripheral surface of the reinforcing bar rod. In addition, a more preferable configuration of the presser reinforcing bar is an annular reinforcing bar having a diameter smaller than that of the hoop bar, which is fixed to the reinforcing bar bar by a plurality of connecting members projecting radially inward from the bar bar. . It is preferable to use a reinforcing bar for the connecting member. In addition, it is preferable that the holding bar is fixed to the reinforcing bar rod by welding.

  Reinforcing bars do not affect the strength retention of concrete piles even if they are accidentally damaged during the removal of residual piles after the pile head buried bag is pulled out. Absent. Moreover, you may remove a holding | suppressing reinforcing bar at the time of the remaining removal removal operation after extracting a pile head embedding bag.

  The pile head embedded bag inserted into the gap portion is inflated by being filled with air from the air inlet, and the bag-like main body has a columnar shape having a sufficiently larger diameter than the gap portion. At this time, the bag-shaped main body is fixed by being pinched by at least the facing portions of the hoop bar and the holding bar. The bag-like main body fixed to the gap portion can maintain the state of being inserted into the gap portion without rising even when buried in the placed concrete.

  The pile head burying bag has a bag-shaped main body made of a flexible and thick resin material, and is a hollow portion formed inside the bag-shaped main body from an air inlet provided at the tip of the bag-shaped main body. Air can be injected. The resin material used for the pile head burying bag can be selected from urethane resin, polyamide resin, nylon resin and the like, and a multilayer structure combining these resin materials is also preferable. The bag-like main body in a state where air is not injected into the hollow portion is in a constricted state and can be easily inserted into the gap portion.

  The operator can inject air into the bag-shaped main body by connecting a compressed air cylinder to the air inlet. The injected air inflates the hollow portion to inflate the bag-like body. Since the bag-shaped main body is made of a thick resin material, the air filled in the hollow portion does not leak to the outside if the air inlet is blocked, and a pile head buried bag was placed. Even if it is embedded in concrete, the swollen shape of the bag-like body can be maintained. Therefore, if a plurality of pile head buried bags in which the bag-like main body is inflated by injecting air is installed in an annular shape along the inner peripheral surface of the reinforcing bar, even if concrete is placed in the excavation hole A pile head can be formed in the region near the inside of the reinforcing bar without entering concrete.

  A plurality of air inlets may be provided for one pile head buried bag. Further, for example, two air inlets may be provided in one pile head buried bag, and one air inlet may be used for injecting air and the other may be used for discharging air.

  On the other hand, when the air filled in the hollow portion is discharged from the air inlet, the volume of the bag-like body contracts to return to the contracted state. At this time, the operator can easily pull out the pile head buried bag by gradually peeling off the outer surface of the bag-shaped main body in close contact with the hardened concrete while grasping and lifting the exposed portion of the bag-shaped main body. Can do. Specifically, since the bag-shaped main body is made of a flexible resin material, the bag-shaped main body can be easily peeled off from the hardened concrete by deforming the bag-shaped main body so as to gradually reduce the diameter.

  According to the present invention, if the pile head burying bag is extracted from the pile head, it is possible to perform an extra work removal operation in the vicinity of the inside of the reinforcing bar rod. Thereby, it is not necessary to crush the surplus in the vicinity of the inside of the reinforcing bar rod, which has been a factor of reducing the efficiency of the pile head processing in particular, and the surplus removal removing operation can be simplified. As a result, the working efficiency can be greatly improved as compared with the conventional pile head processing.

  The pile head embedding bag according to the present invention can be easily removed from the pile head even by human power by grasping and pulling up the bag-shaped main body contracted by exhausting air from the hollow portion after hardening of the concrete. Therefore, according to the present invention, of the conventional pile head processing, it is possible to convert the extra-removal removal work in the vicinity of the inside of the reinforcing bar rod, which was the cause of the decrease in work efficiency, to the easiest work in the pile head processing. It has a remarkable effect of being able to do it. Therefore, the pile head burying bag according to the present invention can contribute to a significant improvement in work efficiency of the pile head processing.

(A) is a front view of the pile head embedding bag 1 which concerns on this invention of the state before filling with air. (B) is a left view of the pile head embedding bag 1 according to the present invention in a state before being filled with air. (A) is AA sectional drawing of the pile head embedding bag 1 concerning this invention of the state before filling with air. (B) is BB sectional drawing of the pile head embedding bag 1 which concerns on this invention of the state before filling with air. It is a front view of the pile head embedding bag 1 of the state with which the hollow part 4 was filled with air. It is a longitudinal cross-sectional view from the left side surface of the pile head burying bag 1 in a state where the hollow portion 4 is filled with air, cut longitudinally at the left and right centers. It is a partial expanded sectional view which cut | disconnected the part which forms the pile head 13 of a cast-in-place concrete pile in the depth direction of the excavation hole 9, Comprising: The pile head embedding bag 1 which concerns on this invention of the state before filling with air It is a figure which shows a mode that it inserts in the clearance gap part 16 and installs. It is the elements on larger scale which cut the portion which forms pile head 13 of a cast-in-place concrete pile in the depth direction of excavation hole 9, and injects air into pile head embedding bag 1, and hoop reinforcement 11 and holding rebar It is a figure which shows a mode that it fixed between 15. The state which fixed the some pile head embedding bag 1 between the hoop reinforcement 11 and the holding reinforcement 15, and installed it cyclically | annularly along the internal peripheral surface of the said reinforcing bar rod 12 from the upper direction of the excavation hole 9. is there. It is a partial expanded sectional view which cut the part which forms the pile head 13 of a cast-in-place concrete pile in the depth direction of the excavation hole 9, and casts concrete into the excavation hole 9 and piles the pile head burying bag 1 It is a figure which shows the state embed | buried under the head. It is a partial expanded sectional view which cut | disconnected the part which forms the pile head 13 of a cast-in-place concrete pile in the depth direction of the excavation hole 9, Comprising: After hardening of the cast concrete, the pile head buried bag 1 is pile head. It is a figure which shows a mode that it extracts from 13. FIG. It is the perspective view which cut the excavation hole 9 in the depth direction, and saw the pile head 13 and the surplus 14 after extracting and removing all the several pile head embedding bags 1 installed in the clearance gap part 16 from diagonally upward. is there. In other embodiment, it is the figure which looked at the state which installed the some pile head embedding bag 1 cyclically | annularly along the inner peripheral surface and outer peripheral surface of the hoop muscle 11, from the upper direction of the excavation hole 9. FIG.

  Hereinafter, embodiments according to the present invention will be described in detail with reference to the drawings. Fig.1 (a) shows the front view of the pile head embedding bag 1 which concerns on this invention which has become a long strip form before being filled with air. Moreover, FIG.1 (b) shows the left view of the pile head embedding bag 1 which concerns on this invention of a long strip form. The pile head processing bag 1 includes a long bag-shaped main body 2 made of a flexible and thick resin material, and an air inlet 3 provided at the tip of the bag-shaped main body 2. As shown in FIGS. 2A and 2B, a hollow portion 4 is formed. The ear | edge part 5a currently formed in the front-end | tip of the bag-shaped main body 2 forms the bag-shaped main body 2 by heat-seal | fusing the front-end | tip of the cylindrical body which consists of the said thick resin material in pressure direction inward. It is a part provided at the time. A bottom plate portion 5b made of a resin material is fitted into the bottom portion of the bag-shaped main body 2 and welded on the inner surface of the bag-shaped main body 2.

  The air inlet 3 includes a conducting pipe 6 that penetrates the inside and outside of the bag-like main body 2 and a screw mouth 7 that can be connected to an external compressed air cylinder A. In addition, it is preferable that the air injection port 3 has a structure in which the air injected at the time of air filling does not flow backward by providing a backflow prevention valve inside.

  As shown in FIG. 1 (b), the pile head embedded bag 1 in a state before being filled with air has a bag-like main body 2 having a long and thin flat band shape. Moreover, the pile head embedding bag 1 in a state before being filled with air can be easily folded and can be easily inserted into a narrow place.

  On the other hand, the pile head embedding bag 1 in a state where the hollow portion 4 shown in FIG. 3 is filled with air has a thickness as compared with the state before the air is filled by the expansion of the hollow portion 4 as shown in FIG. Increases and constitutes a columnar state that is a long columnar body. The pile head embedding bag 1 in a columnar state has a certain degree of elasticity, but retains a pressure resistance so that it is not crushed even when embedded in concrete.

  Next, a pile head processing method according to the present invention using the pile head buried bag 1 will be described.

  In FIG. 5, the partial expanded sectional view which cut | disconnected the part which forms the pile head 13 which is an upper end part of a cast-in-place concrete pile in the depth direction of the excavation hole 9 is shown. The excavation hole 9 is a columnar hole provided by excavating the ground 8 using an excavator, and a concrete pile P that forms the foundation of a building is formed by placing concrete in the excavation hole 9. Is done.

  Before the concrete is placed in the excavation hole 9, a reinforcing bar 12 comprising a pile main bar 10 arranged in the depth direction of the excavation hole 9 and an annular hoop bar 11 connecting the pile main bar 10 in the circumferential direction. Is installed. The upper end portion of the pile head 13 of the cast-in-place concrete pile P is an extra pile 14. In the surplus pile 14, an annular holding rebar 15 is provided inside the excavation hole 9 along the hoop bar 11. A gap 16 is provided between the hoop bar 11 and the presser bar 15 provided on the inside thereof, and a space is formed through which the pile head embedding bag 1 in a state before being filled with air can easily pass. Yes. In the present embodiment, the presser reinforcing bars 15 are provided at two locations corresponding to the two hoop bars 11 from the top of the pile head 13 that are spaced apart from each other. Here, it is preferable that the holding reinforcing bars 15 are provided at three or more locations in the vertical direction. However, in order to stably fix the pile head burying bag 1 with the presser rebars 15, it is preferable that the presser rebars 15 are provided at two positions with a space in the vertical direction.

  Here, the holding reinforcing bar 15 is fixed to the reinforcing bar 12 by a connecting member 17 protruding from the hoop bar 11 inward in the radial direction of the excavation hole 9. In this Embodiment, the connection member 17 consists of reinforcing bars. It is preferable that fixing of the rebar 15 to the reinforcing bar 12 is performed by welding the connecting member 17 to each of the hoop 11 and the rebar 15.

  After the reinforcing bar 12 to which the holding bar 15 is attached is installed in the excavation hole 9, the long-pile pile head buried bag 1 in which the hollow part 4 is not filled with air is formed in the gap part 16 as shown in FIG. Insert. At this time, the air inlet 3 is positioned at the upper part of the pile head embedded bag 1 inserted into the gap portion 16 by inserting the bag-shaped main body 2 with the front end portion facing upward. By inserting the pile head burying bag 1 into the gap portion 16 in this way, it is possible to easily carry in and out the air from the air inlet 3.

  Next, as shown in FIG. 6, a compressed air cylinder A is connected to the air inlet 3 to fill the hollow portion 4 with air. The bag-like main body 2 of the pile head embedded bag 1 expands to form a columnar shape when the hollow portion 4 is filled with air, and the outer surface of the pile head embedded bag 1 is pressed against the hoop bars 11 and the holding reinforcing bars 15. . Thereby, the fixing operation of holding the pile head burying bag 1 between the hoop bar 11 and the holding bar 15 and fixing between the hoop bar 11 and the holding bar 15 can be completed.

  By repeatedly performing the fixing operation along the circumferential direction of the reinforcing bar 12, a plurality of pile head burying bags 1 are installed in an annular shape along the inner peripheral surface of the reinforcing bar 12 as shown in FIG. 7. Thereby, the pile head embedding bag 1 can be spread in the clearance 16.

  After the work of laying and fixing the pile head buried bag 1 in the gap 16 is completed, concrete is placed in the excavation hole 9, and the bag-like main body 2 of the pile head buried bag 1 is buried in the concrete. However, as shown in FIG. 8, the concrete placement is performed until the tip of the pile head burying bag 1 is exposed from the concrete and the air inlet 3 is not buried in the concrete. Thereby, the exhaust of the air after hardening of concrete can be performed easily.

  After the cast concrete is hardened, the air is exhausted from the hollow portion 4 of the pile head burying bag 1 by opening the exposed air inlet 3. As the air is exhausted, the volume of the bag-like body 2 contracts to return to the long-strip shape. The operator can grip the exposed portion of the contracted bag-shaped main body 2. At this time, the operator gradually peels the outer surface of the bag-shaped main body 2 in close contact with the hardened concrete as shown in FIG. The head embedding bag 1 can be easily pulled out. Specifically, since the bag-shaped main body 2 is made of a flexible resin material, the bag-shaped main body 2 can be easily peeled off from the hardened concrete by deforming the bag-shaped main body 2 so as to gradually reduce the diameter.

  Further, at the same time as the pile head burying bag 1 is pulled out in the direction of arrow a in FIG. 9, a space is formed in the gap portion 16 in which the pile head processing bag 1 is embedded, and the excess area near the inside of the reinforcing bar 12 is removed. Work can be done.

  When all of the plurality of pile head buried bags 1 embedded in the concrete are pulled out, an annular space is formed in the vicinity of the inside of the hoop muscle 11 in the pile head 13 of the concrete pile P as shown in FIG. The surplus pile 14 remains in the center part separated from the pile main reinforcement 10.

  Thereby, it is not necessary to crush the surplus in the vicinity of the inside of the reinforcing bar 12 that has been a factor of the reduction in the efficiency of the pile head processing, and the surplus removal operation can be simplified. Furthermore, it is possible to suppress the occurrence of an accident in which the pile main bar 10 is accidentally damaged in the extra-strip removal work performed while crushing the extra-strip 14 using a drill or the like. As a result, the working efficiency can be greatly improved as compared with the conventional pile head processing.

  In addition, even if the remaining reinforcement 14 after the pile head burying bag 1 is removed is accidentally damaged, it does not affect the strength maintenance of the concrete piles. Will not lower. Moreover, it is good also as removing the holding | suppressing reinforcement 15 at the time of the remainder removal removal operation after the pile head burying bag 1 extraction.

  As another embodiment, an outer edge holding reinforcing bar that forms an outer edge gap portion 18 between the hoop bar 11 along the circumferential direction on the outer peripheral surface side of the pile head 13 that is the upper end portion of the reinforcing bar 12. 19 is also preferable.

  In this case, after the reinforcing bar 12 is installed in the excavation hole 9, the pile head burying bag 1 is inserted into the outer edge gap portion 18 so that the distal end portion faces upward in the state of the long band. And by filling the air from the air inlet 3 to make the pile head buried bag 1 into a columnar form, by sandwiching the outer surface of the pile head buried bag 1 between the hoop bar 11 and the outer edge holding bar 19, An outer edge fixing operation for fixing the pile head burying bag 1 between the hoop bar 11 and the outer edge holding bar 19 is performed.

  Further, by repeatedly performing the outer edge fixing operation along the circumferential direction of the reinforcing bar rod, a plurality of pile head embedded bags 1 are installed in an annular shape along the outer peripheral surface of the reinforcing bar rod 12. In addition, the pile head embedded bag 1 is sandwiched between the hoop bar 11 and the holding bar 15 and fixed between the hoop bar 11 and the holding bar 15 on the inner surface side of the hoop bar 1 as in the previous embodiment. Do.

  FIG. 11 shows the state in which the pile head burying bag 1 is thus installed as viewed from above the excavation hole 9.

  Note that the presser reinforcing bar 15 and the outer edge presser reinforcing bar 19 are fixed to the reinforcing bar 12 by a connecting member 20 protruding from the hoop bar 11 radially inward and radially outward of the excavation hole 9. In the other embodiment, the connecting member 20 is made of a reinforcing bar. Fixing of the holding bar 15 and the outer edge holding bar 19 to the reinforcing bar 12 is preferably performed by welding the connecting member 20 to the hoop bar 11, the holding bar 15, and the outer edge holding bar 19.

  Thereafter, concrete is placed in the excavation hole 9 and the bag-like main body 2 of the pile head burying bag 1 is embedded in the concrete. However, the concrete is placed until the tip of the pile head burying bag 1 is exposed from the concrete and the air inlet 3 is not buried in the concrete. Thereby, the exhaust of the air after hardening of concrete can be performed easily.

  After the cast concrete is hardened, the air is exhausted from the hollow portion 4 of the pile head burying bag 1 by opening the exposed air inlet 3. The operator can easily lift the pile head embedded bag 1 by gradually peeling the outer surface of the bag-shaped main body 2 in close contact with the hardened concrete from the tip direction while grasping and pulling up the exposed portion of the contracted bag-shaped main body 2. Can be pulled out. Specifically, since the bag-shaped main body 2 is made of a flexible resin material, the bag-shaped main body 2 can be easily peeled off from the hardened concrete by deforming the bag-shaped main body 2 so as to gradually reduce the diameter.

  At the same time that the pile head burying bag 1 is pulled out, a space is formed in the gap portion 16 and the outer edge gap portion 18 in which the pile head treatment bag 1 has been buried, and the extra-strip removal work in the vicinity of the inside and outside of the reinforcing bar 12 can be performed. it can.

  When all of the plurality of pile head burying bags 1 embedded in the concrete are pulled out, an annular space is formed in the pile head 13 of the concrete pile P in the vicinity of the inside and outside of the hoop reinforcement 11 and separated from the pile main reinforcement 10. The surplus pile 14 remains in the center.

  By providing the outer edge holding reinforcing bar 19 and installing the pile head processing bag 1 in the outer edge gap portion 18, not only the area near the inside of the pile main bar 10 and the hoop bar 11 in the pile head 13 but also the outer side of the hoop bar 11. It is possible to place concrete without adhering the concrete to a nearby region. For this reason, the efficiency of a pile head process can be improved further.

DESCRIPTION OF SYMBOLS 1 Pile head embedding bag 2 Bag-shaped main body 3 Air inlet 4 Hollow part 9 Excavation hole 10 Pile main reinforcement 11 Hoop reinforcement 12 Reinforcement rod 13 Pile head 14 Extra pile 15 Reinforcing bar 16 Gap part 17 Connection member

Claims (3)

Reinforcing rods made up of pile main bars arranged in the depth direction of the hole in the excavation hole provided in the ground and an annular hoop bar connecting the pile main bars in the circumferential direction are installed, and after the installation of the reinforcing bar rods, the excavation A pile head treatment method that removes the extra pile head pile of a cast-in-place concrete pile formed by placing concrete in a hole,
On the inner peripheral surface side of the upper end portion of the reinforcing bar rod, a holding reinforcing bar that forms a gap between the hoop bar along the circumferential direction is provided,
Installing the reinforcing bar in the excavation hole,
A bag-like main body formed of a flexible and thick resin material having a hollow portion inside, and an air inlet provided at the tip of the bag-like main body, and when filled with air, from the gap portion A pile head embedded bag that has a long column shape that is a long flat body that can be easily passed through the gap when the air is exhausted. Insert in the gap so that the tip is upward in the state of the band,
Filling the air from the air inlet to form the pile head buried bag in a columnar form, and sandwiching the outer surface of the pile head buried bag between the hoop bar of the reinforcing bar rod and the presser reinforcing bar, Perform the fixing work to fix the pile head burying bag between the hoop bar and the holding bar,
By repeatedly performing the fixing operation along the circumferential direction of the reinforcing bar rod, a plurality of pile head buried bags are installed annularly along the inner circumferential surface of the reinforcing bar rod,
By embedding concrete to a position where the air inlet can be exposed to the excavation hole, the bag-like main body of the pile head burying bag is embedded in the concrete pile head placed,
After the concrete is hardened, by opening the air inlet, air is exhausted from the hollow portion of the pile head buried bag and the bag-shaped body is contracted to form a long-band shape, and the bag-shaped body in the long-band shape And pulling out the plurality of pile head buried bags from the pile head,
The pile head processing method characterized by removing the remaining surplus. On the outer peripheral surface side of the upper end portion of the reinforcing bar bar, an outer edge holding reinforcing bar that forms an outer edge gap portion between the hoop bar along the circumferential direction is provided,
After installing the reinforcing bar in the excavation hole,
The pile head buried bag is inserted into the outer edge gap portion so that the tip portion is upward in the state of the long band,
Filling air from the air inlet to form the pile head buried bag in a columnar form, and sandwiching the outer surface of the pile head buried bag between the hoop of the reinforcing bar rod and the outer edge holding reinforcing bar, the reinforcing bar rod The outer edge fixing work for fixing the pile head buried bag between the hoop bar and the outer edge holding bar is performed,
The plurality of pile head burying bags are installed in an annular shape along the outer peripheral surface of the reinforcing bar rod by repeatedly performing the outer edge fixing operation along the circumferential direction of the reinforcing bar rod. Pile head treatment method. A reinforcing bar made of a pile main bar arranged in the depth direction of the hole in the excavation hole provided in the ground and an annular hoop bar connecting the pile main bar in the circumferential direction, and the reinforcing bar installed in the excavation hole On the inner peripheral surface side of the upper end portion of the rod, a presser reinforcing bar provided with a gap portion between the hoop bars is installed along the circumferential direction, and concrete is placed in the excavation hole after the reinforcing bar rod is installed. A pile head burying bag used in a pile head processing method for removing excess pile head piles of cast-in-place concrete piles formed by casting,
A bag-like main body made of a flexible and thick resin material having a hollow portion inside, and an air inlet provided at the tip of the bag-like main body,
It is a long flat body that forms a columnar form that is a long columnar body that has a sufficiently larger diameter than the gap when filled with air, and that can easily pass through the gap when air is discharged. Forming a long belt form,
A plurality of annularly inserted along the inner peripheral surface of the reinforcing bar rod in the gap portion so that the tip portion is upward in the state of the long band shape,
A columnar shape is formed by filling air from the air inlet, and an outer surface is sandwiched between the hoop of the rebar bar and the presser bar, so that the hoop bar and the presser bar of the bar bar are Fixed between and
Embedded in the concrete pile head placed against the excavation hole, until the tip portion is upward and the air inlet provided in the tip portion can be exposed,
After the concrete is hardened, air is exhausted from the hollow portion by opening the air inlet, and the bag-shaped main body is contracted to form a long band shape, and the bag-shaped main body in the long band shape is gripped. When the pile head is pulled out from the pile head, an extra pile is formed on the pile head.

Images