JP6849523B2 - Outer shell steel pipe concrete pile and its manufacturing method - Google Patents

Description

The present invention relates to an outer shell steel pipe concrete pile in which a steel pipe portion is provided on the outside of a pile body portion formed of concrete, and a method for manufacturing the same.

At the points where the foundation piles are joined to the footing, the horizontal force due to the earthquake is the strongest and acts on the foundation piles. Excellent outer shell steel pipe concrete piles (SC piles) may be used.

However, since the fractured form of the SC pile is often a cross-sectional defect due to the peeling of the inner surface concrete on the compression side, local buckling may occur in the steel pipe, and the deformation performance as designed may not be obtained.

As a technique for improving the horizontal strength of this type of concrete pile, for example, as shown in Patent Document 1 and Patent Document 2, tension steel material (PC steel material) is applied to the concrete pile main body of the SC pile along the axial direction. Is known to be configured.

In the configuration in which the PC steel material is provided on the concrete pile body portion in this way, the PC steel material is arranged substantially at the center of the wall thickness of the pile body portion in order to apply the compressive force as evenly as possible in the cross-sectional direction of the pile body portion. , It is necessary to fix the end part to the end plate (anchor body).

Further, as a technique for improving the horizontal strength, a configuration in which a non-tensile steel material (reinforcing bar) is arranged in a concrete pile main body of an SC pile is known.

In such a configuration in which the reinforcing bars are arranged on the concrete pile body, if the reinforcing bars are not fixed to the end plate, the reinforcing bars may be misaligned due to the compaction by centrifugal force during pile manufacturing. There is.

Therefore, for example, as shown in Patent Document 3 and the like, a method of casting and forming concrete in a state where a reinforcing bar is inserted and fixed in a hole provided in a ring-shaped steel plate or a groove provided in an annular guide plate is used. For example, as shown in Patent Document 4, a method is known in which concrete is cast and formed in a state where a reinforcing bar is welded and fixed to an inner peripheral surface of a steel pipe.

Further, as a technique for improving the horizontal strength, for example, as shown in Patent Document 5, a substantially L-shaped (mountain-shaped) steel material is arranged in a concrete pile main body instead of a linear reinforcing bar in a cross-sectional view. The composition is known.

Jikkai Sho 51-11704 Jikkai Sho 58-10938 Japanese Unexamined Patent Publication No. 2011-137320 Jikkaisho 51-142703 Jikkai Sho 57-114834

However, although the methods of Patent Document 1 and Patent Document 2 can improve the horizontal strength, the PC steel material is thin and its rigidity is small, so that it is not possible to prevent the inner surface concrete from peeling off.

In the method of Patent Document 3, many parts are required to fix the reinforcing bar, which causes an increase in cost and complicates the manufacturing work. Further, since the circumference of the reinforcing bar becomes narrow in the formwork, there is a possibility that the concrete does not properly spread around the reinforcing bar when placing concrete.

The method of Patent Document 4 is effective for improving the horizontal strength, but since the reinforcing bars are arranged along the steel pipe, it is not possible to prevent the inner surface concrete from peeling off.

In the method of Patent Document 5, since the stress received by the steel pipe and the stress received by the shaped steel material are different and the amount of deformation between the steel pipe and the shaped steel material is also different, the internal stress is applied to the portion where the shaped steel material is fixed to the steel pipe. May occur and the original strength may not be exhibited.

Further, the shaped steel material cannot be easily fixed in the steel pipe, which complicates the manufacturing work, and since the shaped steel material is fixed to the steel pipe, it is difficult for the concrete to spread around the shaped steel material when the concrete is placed.

Therefore, there has been a demand for an outer shell steel pipe concrete pile that can prevent the inner surface concrete from peeling off, improve the deformation performance, can reliably cast the concrete around the reinforcing steel material, and is easy to manufacture.

The present invention has been made in view of such a point, and an object of the present invention is to provide an outer shell steel pipe concrete pile which can improve deformation performance and is easy to manufacture, and a method for manufacturing the same.

The outer shell steel pipe concrete pile according to claim 1 includes a pile main body formed of concrete, a tubular steel pipe portion provided outside the pile main body portion, and the pile main body portion and the steel pipe portion. An end face steel plate provided at both ends in the axial direction and a reinforcing body provided inside the pile body portion are provided, and the end face steel plate has a holding member protruding toward the pile body portion and is reinforced. The body is composed of a plurality of first steel bodies whose both ends are held by the holding member, a second steel body that is not held by the holding member, and the first steel body and the second steel body. have a third steel body that is crossed and fixed, wherein one of the holding member and the first steel member is a linear or bar, the other of said retaining member and said first steel body It has an engaging portion that is expanded in a direction intersecting the axial direction and can engage one of the holding member and the first steel body from the direction intersecting the axial direction .

The outer shell steel pipe concrete pile according to claim 2 is the outer shell steel pipe concrete pile according to claim 1, wherein both ends of the first steel body are placed and held on a holding member. ..

The outer shell steel pipe concrete pile according to claim 3 is the outer shell steel pipe concrete pile according to claim 1 or 2, in which the other of the holding member and the first steel body expands in a direction intersecting the axial direction. It is a shaped steel having an engaging portion .

The method for manufacturing an outer shell steel pipe concrete pile according to claim 4 is the method for manufacturing an outer shell steel pipe concrete pile according to any one of claims 1 to 3, wherein a reinforcing body is inserted into the steel pipe portion and the steel pipe is said. both ends of the first steel member in said reinforcement the engagement portion of the retaining member end surface steel plate and Turkey be held respectively put in the direction intersecting the axial direction in both square side in the axial direction of the parts, The reinforcing body is positioned in the steel pipe portion, and concrete is cast and formed.

According to the present invention, a first steel body in which both ends are engaged and held by engaging portions of the holding member from a direction intersecting the axial direction, and a second steel body not held by the holding member. Therefore, the deformation performance can be improved and the product can be easily manufactured.

It is sectional drawing which shows the structure of the outer shell steel pipe concrete pile which concerns on 1st Embodiment of this invention. It is the schematic sectional drawing of the outer shell steel pipe concrete pile of the same as above. It is sectional drawing which shows the structure of the outer shell steel pipe concrete pile which concerns on 2nd Embodiment of this invention. It is sectional drawing which shows the structure of the outer shell steel pipe concrete pile which concerns on 3rd Embodiment of this invention. It is a schematic sectional view of the outer shell steel pipe concrete pile of the same as above.

Hereinafter, the configuration of the first embodiment of the present invention will be described in detail with reference to the drawings.

In FIGS. 1 and 2, an outer shell steel pipe concrete pile 1 is shown, and the outer shell steel pipe concrete pile 1 is a steel pipe formed into a cylindrical shape with a steel plate on the outside of a pile main body 2 formed into a cylindrical shape with concrete. Part 3 is provided. In FIG. 2, the pile main body 2 is shown by a chain double-dashed line.

Further, annular end face steel plates 4 are provided at both ends of the pile main body 2 and the steel pipe 3 in the axial direction, and a reinforcing bar cage 5 as a reinforcing body is provided inside the pile main body 2.

That is, the outer shell steel pipe concrete pile 1 is provided with a pile main body portion 2 which is a concrete layer integrally inside the steel pipe portion 3 and the end face steel plate 4, and a reinforcing bar cage is embedded inside the pile main body portion 2. 5 is provided.

The end face steel plate 4 is provided so that the inner side surface is in contact with the axial end portions of the pile main body portion 2 and the steel pipe portion 3.

Further, the end face steel plate 4 is provided with a plurality of (for example, four) holding members 11 so as to project from the inner side surface toward the pile main body portion 2.

As shown in FIG. 1, the holding member 11 is a substantially V-shaped (mountain-shaped) steel material that is thin in one direction (for example, downward in FIG. 1) in a cross-sectional view, and the engaging portion 12 is formed by an acute-angled portion. Has been done. Further, the holding member 11 is provided apart from the steel pipe portion 3 in a state where the engaging portion 12 is arranged in the same direction (for example, the upper side in FIG. 1).

The reinforcing bar cage 5 has a plurality of (for example, four) first reinforcing bars 13 as first steel bodies arranged along the axial direction in the pile main body 2, and is substantially parallel to these first reinforcing bars 13. On the second reinforcing bars 14 as a plurality of (for example, eight) second steel bodies arranged along the axial direction in the pile main body 2, and these first reinforcing bars 13 and the second reinforcing bars 14. It has a third reinforcing bar 15 as a third steel body fixed so as to intersect.

The first reinforcing bar 13 is a rod-shaped steel material, and is arranged at a predetermined pitch along the circumferential direction of the pile main body 2 so as to correspond to the arrangement of the holding member 11 on the end face steel plate 4.

The second reinforcing bar 14 is a rod-shaped steel material similar to the first reinforcing bar 13, and two second reinforcing bars 14 are arranged at a predetermined pitch between the first reinforcing bars 13 in the circumferential direction of the pile main body 2. It is stakeout.

That is, the first reinforcing bar 13 and the second reinforcing bar 14 are arranged in the same circumferential direction of the pile main body portion 2 and are arranged apart from the steel pipe portion 3 in the radial direction of the pile main body portion 2.

The third reinforcing bar 15 is a linear steel material, and is spirally arranged inside the first reinforcing bar 13 and the second reinforcing bar 14 in the pile main body 2 in the radial direction. Further, the third reinforcing bar 15 is fixed to each of the first reinforcing bar 13 and each second reinforcing bar 14 by welding.

That is, the reinforcing bar cage 5 is formed in a cage shape by connecting the third reinforcing bar 15 extending in the intersecting direction to the first reinforcing bar 13 and the second reinforcing bar 14 which are parallel to each other.

Such a reinforcing bar cage 5 is inserted into the steel pipe portion 3 before placing concrete, and both ends of each of the first reinforcing bars 13 are placed so as to be engaged with the engaging portion 12 of the holding member 11. By being placed, it is held against the end face steel plate 4. That is, in the reinforcing bar cage 5, the second reinforcing bar 14 is not held by the holding member 11 of the end face steel plate 4, but the first reinforcing bar 13 held by the holding member 11 is held via the third reinforcing bar 15. The second reinforcing bar 14 is fixed. Further, concrete is cast while the relative positions of the first reinforcing bar 13, the second reinforcing bar 14, and the third reinforcing bar 15 in the steel pipe portion 3 are maintained in this way.

Next, a method for manufacturing the outer shell steel pipe concrete pile 1 will be described.

When manufacturing the outer shell steel pipe concrete pile 1, first, the end face steel plate 4 is fixed to one end of the steel pipe portion 3 in the axial direction.

The reinforcing bar cage 5 is inserted from the other end in the axial direction of the steel pipe portion 3 toward one end, and one end of each first reinforcing bar 13 in the reinforcing bar cage 5 is engaged with each holding member 11 in the end face steel plate 4. It is placed and held so as to engage with the portion 12.

Further, the other end of each of the first reinforcing bars 13 in the reinforcing bar cage 5 is placed and held so as to engage with the engaging portion 12 of each holding member 11 in the end face steel plate 4, and the end face steel plate 4 is held. It is fixed to the other end of the steel pipe portion 3 in the axial direction.

By holding the first reinforcing bar 13 of the reinforcing bar cage 5 on the holding member 11 of the end face steel plate 4 in this way, the reinforcing bar cage 5 is positioned at a predetermined position in the steel pipe portion 3.

Then, with the reinforcing bar cage 5 positioned in the steel pipe portion 3, concrete is poured and molded by centrifugal compaction or the like.

Next, the operation and effect of the first embodiment will be described.

According to the outer shell steel pipe concrete pile 1 according to the first embodiment, the first reinforcing bar 13 and the second reinforcing bar 14 are arranged along the axial direction in the pile main body 2. The first reinforcing bar 13 and the second reinforcing bar 14 act to hold the concrete constituting the pile main body 2, and even if the outer shell steel pipe concrete pile 1 is greatly deformed, the inner surface concrete is hard to peel off. Therefore, local buckling is less likely to occur in the steel pipe portion 3, the deformation performance can be improved, and the deformation performance based on the design can be obtained.

Further, since the first reinforcing bar 13 and the second reinforcing bar 14 are not directly fixed to the steel pipe portion 3, internal stress is generated based on the fixing of the first reinforcing bar 13 and the second reinforcing bar 14 to the steel pipe portion 3. In addition, when placing concrete, a space can be secured between the reinforcing bar cage 5 and the steel pipe portion 3, and around the first reinforcing bar 13, the second reinforcing bar 14, and the third reinforcing bar 15. The concrete can be distributed reliably.

In the reinforcing bar cage 5, since the first reinforcing bar 13 is held by the holding member 11, the position of the reinforcing bar cage 5 in the steel pipe portion 3 when placing concrete or forming by centrifugal compaction or the like. Can be prevented from moving.

In the reinforcing bar cage 5, since only the first reinforcing bar 13 needs to be held by the holding member 11, for example, the shapes of the second reinforcing bar 14 and the third reinforcing bar 15 may be changed according to the required proof stress and other performance. The length, arrangement, number, etc. can be changed, it can be manufactured economically, and it is easy to meet various required performances.

Further, since it is easy for the reinforcing bar cage 5 to bear a part of the yield strength originally required for the steel pipe portion 3, the steel pipe portion 3 can be formed of a steel plate having a relatively thin plate thickness.

Since both ends of the first reinforcing bar 13 are held so as to be placed on the holding member 11 of the end face steel plate 4, it is easy to position the reinforcing bar cage 5 in the steel pipe portion 3 at the time of manufacturing.

Further, since both ends of the first reinforcing bar 13 are engaged with the engaging portion 12 of the holding member 11 in the end face steel plate 4, it is easy to position the reinforcing bar cage 5 in the steel pipe portion 3 at the time of manufacturing, and the concrete It is difficult for the holding member 11 to release the holding state of the first reinforcing bar 13 at the time of casting or molding.

Therefore, according to the outer shell steel pipe concrete pile 1 and the manufacturing method thereof, the deformation performance can be improved and the pile can be easily manufactured.

In the first embodiment, the engaging portion 12 of each holding member 11 is arranged in the same direction with respect to the end face steel plate 4, but the structure is not limited to this and the end face steel plate is not limited to this structure. The orientation of the holding member 11 in 4 can be changed as appropriate.

That is, for example, as in the second embodiment shown in FIG. 3, each holding member 21 may have a configuration in which the engaging portions 22 are arranged on different sides and face different directions.

Further, in the first embodiment, the first reinforcing bar 13 and the second reinforcing bar 14 are formed of a rod-shaped steel material, the third reinforcing bar 15 is formed of a linear steel material, and the holding member 11 is a shaped steel material. However, the configuration is not limited to such a configuration, and if the first reinforcing bar 13 can be held by the holding member 11, the first reinforcing bar 13, the third reinforcing bar 15, and the third reinforcing bar 13 can be held. The shapes and the like of the reinforcing bar 14 and the holding member 11 of 2 can be changed as appropriate.

Further, the structure is not limited to the structure in which the holding member 11 is provided with the engaging portion 12, and the first reinforcing bar cage 30 as a reinforcing body is formed as in the third embodiment shown in FIGS. 4 and 5, for example. A structure in which the engaging portion 34 is provided on the steel body 31 of the above may be used.

In the third embodiment, the first steel body 31 and the second steel body 32 in the reinforcing bar cage 30 are formed of a substantially V-shaped steel material in a cross-sectional view and have an engaging portion 34.

Further, a third steel body 33, which is a linear steel material, is fixed to the inner ends of the first steel body 31 and the second steel body 32 in the radial direction of the pile body portion 2 by welding.

Further, the holding member 35 is formed of a rod-shaped steel material, and the first steel body 31 is engaged and held so as to cover the rod-shaped holding member 35.

1 Outer shell steel pipe concrete pile 2 Pile body 3 Steel pipe 4 End face steel plate 5 Reinforcing bar cage as a reinforcing body
11 Holding member
12 Engagement part
13 First reinforcing bar as the first steel body
14 Second rebar as the second steel body
15 Third rebar as a third steel body
21 Holding member
22 Engagement part
30 Reinforcing bar cage as a reinforcing body
31 First steel body
32 Second steel body
33 Third steel body
34 Engagement part
35 Holding member

Claims (4)

The pile body molded from concrete and
A tubular steel pipe provided on the outside of the pile body and
End face steel plates provided at both ends of the pile body and the steel pipe in the axial direction, and
It is provided with a reinforcing body provided inside the pile body portion.
The end face steel plate has a holding member that projects toward the pile body portion.
The reinforcing body includes a plurality of first steel bodies whose both ends are held by the holding member, a second steel body that is not held by the holding member, and the first steel body and the second steel. have a third steel body fixed to intersect the body,
One of the holding member and the first steel body is linear or rod-shaped.
The other of the holding member and the first steel body is expanded in a direction intersecting the axial direction, and one of the holding member and the first steel body can be engaged from a direction intersecting the axial direction. An outer shell steel pipe concrete pile characterized by having a joint. The outer shell steel pipe concrete pile according to claim 1, wherein both ends of the first steel body are placed and held on a holding member. The outer shell steel pipe concrete pile according to claim 1 or 2 , wherein the other of the holding member and the first steel body is a shaped steel having an engaging portion that expands in a direction intersecting the axial direction. The method for manufacturing an outer shell steel pipe concrete pile according to any one of claims 1 to 3.
Insert the reinforcing body into the steel pipe part and
And Turkey to hold each put both ends of the first steel member in the reinforcement in the engaging portion of the holding member of the end face steel plate in the direction intersecting the axial direction in both square side in the axial direction of the steel pipe section Then, the reinforcing body is positioned in the steel pipe portion, and the reinforcing body is positioned.
A method for manufacturing an outer shell steel pipe concrete pile, which is characterized by placing and forming concrete.

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