JP6289140B2 - Construction pillar construction method - Google Patents

Description

  In the present invention, an integrated object in which an off-the-shelf pile (for example, a PC pile or a PHC pile) and a structural pillar (for example, an H-shaped steel) are integrated with each other while rotating around an axis using a yatco. It relates to the construction method of the true pillar built in.

In general, the installation of a structural pillar in accordance with the reverse driving method is to construct the structural pillar in the ground and to construct the lower end of the structural pillar before the concrete of the structural pillar hardens. It has been practiced to insert into the upper end of the mandrel and harden it integrally. According to this method, the construction of the pillar is made up of the formation of a pile hole by excavation using a stabilizing liquid with a large excavator, and then lowering the rebar cage into the pile hole and filling with concrete. It was necessary, the procedure was complicated, and the construction period was long.
As a method that can solve such problems, there is a method of using a ready-made pile instead of a conventional built-up column and building it in the ground with the ready-made pile and the built-up column integrated (for example, patents) Reference 1).

The detailed procedure of this method is to dig a hole for laying a pile in the ground in advance and inject a root-setting liquid into the hole, and rotate the pre-made pile and built-up column around the axis to the hole. It is carried out by pushing in.
As shown in FIG. 9, a “Yatco” Z capable of transmitting a driving force across the drive shaft Ma of the rotational driving device M and the integral P is used for the rotational drive of the integral. The upper end portion of the YATCO Z is attached to the drive shaft Ma of the rotary drive device M, and the lower end portion of the YATCO Z is formed to have a large diameter so that it can be externally fitted to an integral object P having a larger diameter than the drive shaft Ma. The rotational driving force is transmitted from the rotational driving device M to the one-piece object P with respect to the rotational driving force transmission protrusion 2b provided on the outer peripheral portion of the one-piece object P by the engagement recess Za provided at the lower end portion of the yoke. It can be implemented by engaging.

  Conventionally, in this type of construction of the pillar, the “Yatco” Z used is formed as a large-diameter portion that can be externally fitted to the integrated object P as shown in the figure, and has a lower end portion. The length of the engaging recess Za is set so as to be engaged with the ready-made pile 2 located on the lower end side of the intermediate portion in the longitudinal direction of the monolith P. Therefore, when rotating the monolith P, the engaging recess Za at the lower end of the yatko is swallowed in the large diameter portion of the yat Z while the structural pillar 1 positioned on the upper end side of the middle part in the longitudinal direction of the monolith P is swallowed. Is engaged with the protrusion 2b of the ready-made pile 2, and the rotational driving force from the rotational drive device M is directly transmitted to the ready-made pile P (for example, see Patent Document 1).

JP-A-6-49855 (FIG. 5)

According to the above-mentioned conventional frame construction method, the rotational drive force of the rotational drive device is directly transmitted to the ready-made pile in the integral object, and the integral object is built, so that it is used for it. Since Yatco became long and the handleability was poor, the construction efficiency was reduced.
In addition, as a Yatco, it is necessary to have sufficient strength to transmit the rotational driving force, so a thick cylindrical member will be used over the entire length, and the handleability deteriorates further due to the increase in weight, This leads to a decrease in construction efficiency.
In addition, since the Yatco and the ready-made pile have a connection structure by engaging the protrusion and the engaging recess, there is a possibility that the axis of each other may be bent, and the verticality measurement of the Yatco that can be directly measured by visual confirmation when built However, there is a risk that the integrated object located in the inner space of the Yatco is inclined, and the vertical accuracy of the integrated object tends to be lowered.

  Accordingly, an object of the present invention is to provide a construction column construction method capable of solving the above-mentioned problems and efficiently and accurately incorporating a construction column.

The first characteristic configuration of the present invention is a construction column construction method in which an integrated body obtained by integrating a ready-made pile and a construction column is built in the ground while rotating around an axis using a Yatco. The Yatco is connected to the true pillar to transmit a rotational force, and the true pillar has a removal target portion that is removed after the main pillar is completed .

According to the first characteristic configuration of the present invention, the yatco is connected to the true pillar to transmit the rotational force, so that the unitary object can be obtained by using the yatco of the minimum length without using the long yatco as in the prior art. Rotation can be implemented.
Therefore, by minimizing the weight and reducing the weight, the handleability is improved, the construction efficiency can be improved, the construction period can be shortened, and the cost can be reduced.
Furthermore, when the monolith is built, the verticality can be measured by visual confirmation of the structure pillar portion, and the monolith can be built with high vertical accuracy.

The second characterizing feature of the present invention, in the longitudinal direction of at least part of the pre-Symbol removal target part, there is to the separation closable short form steel Aru incorporated.

In the reverse driving method, when the main pillar is installed separately from the construction pillar, when the construction pillar is completed, the removal target part of the construction pillar will be removed. Axial force remains in the column, and this axial force tends to be an obstacle when the removal target part is pulled out sideways.
According to the second characteristic configuration of the present invention, since the separable short steel is incorporated into at least a part of the longitudinal direction of the removal target portion of the stem column, the pulling force is applied to the short steel. Even in a narrow work space in the basement, the axial force can be released by easily extracting the short steel without interfering with the surroundings.
Therefore, it is possible to remove the structural pillar more efficiently and without adversely affecting the surroundings, compared to extracting the structural pillar made of a single long steel.

  According to a third characteristic configuration of the present invention, the short steel is configured in advance as a temporary general-purpose product in which a plurality of bolt holes are formed at predetermined intervals.

  According to the 3rd characteristic structure of this invention, the combination of the short material according to a field condition can be performed, and connection and a disassembly can be implemented more easily. In addition, the cost can be reduced by diverting the short steel.

Explanatory drawing showing construction pillar construction method Explanatory drawing showing construction pillar construction method Explanatory drawing showing construction pillar construction method Explanatory drawing showing construction pillar construction method The perspective view which shows the connection situation of a construction pillar and ready-made pile Perspective view showing the installation status of Yatco Explanatory diagram showing the removal status of the construction pillar Explanatory diagram showing the removal status of the construction pillar Explanatory drawing showing the conventional construction method

  Embodiments of the present invention will be described below with reference to the drawings. In the drawings, the parts indicated by the same reference numerals as those in the conventional example indicate the same or corresponding parts.

  FIGS. 7 and 4 show an embodiment of the construction method of the timber pillar according to the present invention. In the building B formed by the reverse driving method, the construction of the ground part B1 is performed in parallel with the construction of the underground part B0. In order to proceed, the construction pillar 1 which becomes a supporting pillar is installed in the basement in the initial construction stage so that the load of the ground portion B1 can be supported by the construction pillar 1.

  When the structural pillar 1 is built in the ground G, as shown in FIGS. 1 to 4, the ready-made pile 2 that serves as the structural pillar to support the structural pillar 1 is attached to the lower end portion of the structural pillar 1. It is installed in the state of the integrated object P connected integrally.

  The structural pillar 1 is made of H-shaped steel. In addition, as shown in FIGS. 7 and 8, the structural pillar 1 described here is not used as the main pillar B0a of the basement B0, but receives a load from above by the separately formed main pillar B0a. It will be installed as a temporary pillar. Therefore, after the completion of the main pillar B0a, the structural pillar part exposed above the foundation beam B0b is removed. Therefore, in order to efficiently carry out the division at the time of removal, the structural pillar 1 is configured so as to be provided with a division target portion 1A embedded in the foundation beam B0b and a removal target portion 1B to be removed. is there.

Since the embedment target portion 1A is embedded in the foundation beam B0b, H-shaped steel that does not have bolt holes in the web or flange is used as a measure for preventing strength reduction.
Further, the lower end portion of the embedment target portion 1A is inserted into the hollow portion V of the ready-made pile 2 from the upper end side to be integrated. Specifically, as shown in FIG. 5, the grooved steel 3 is separately integrated with the outer surfaces of both flanges of the H-shaped steel constituting the embedment target portion 1 </ b> A by welding. By welding to the annular metal part 2a provided on the upper end surface of the ready-made pile 2, the structural pillar 1 and the ready-made pile 2 are integrated.

As shown in FIGS. 2 to 4, the removal target portion 1 </ b> B is composed of short H-section steel (an example of short-shape steel) 1 </ b> Ba and 1 </ b> Bb divided into two in the longitudinal direction. These short H-section steels 1Ba and 1Bb are constituted by temporary general-purpose products in which bolt holes arranged at predetermined intervals on a web or a flange are formed.
The temporary general-purpose product is used for, for example, a mountain retaining work.
Moreover, the to-be-engaged jig | tool 4 which can engage the Yachtoko Y mentioned later freely is attached to the upper end part of the removal object part 1B.
The engaged jig 4 is integrated with a short H-shaped steel 4a, a circular jig body 4b bolted to the upper end thereof, and a radially projecting state on the outer periphery of the jig body 4b. And an engaging projection 4c provided on the surface.
In the state where the engagement recess Y2a of the Yatco Y is engaged with the engagement protrusion 4c of the engaged jig 4 attached to the upper end portion of the stem 1 as shown in FIG. By transmitting the rotational force from M to the frame column 1 via the Y-cots Y and the engaged jig 4, the frame column 1 and the ready-made pile 2 can be integrally rotated around the axis X.

  Each H-section steel used for the embedment target portion 1A, the removal target portion 1B, and the engaged jig 4 is provided with an end face plate E (see FIG. 5). The connection is made by bolt connection in a state where the end face plates E are overlapped. Therefore, at the time of assembling or dismantling and removing the structural pillar 1, it can be easily performed by an operation of attaching and detaching the bolt.

In the embodiment, the ready-made pile 2 is described by taking a pretension type centrifugal force high-strength prestressed concrete pile as an example. The outer shape is configured as a cylindrical shape in which the central portion of the circular cross section becomes the hollow portion V, and the hollow portion V is open on both end faces in the longitudinal direction.
On both end faces of the ready-made pile 2, annular metal portions 2a are integrally provided together with concrete. Further, although not shown in the figure, PC steel and helical rebar are embedded in the concrete.

As shown in FIG. 6, the Yatco Y is installed between the drive shaft Ma of the rotation drive device M and the engaged jig 4, and transmits the rotation drive force of the rotation drive device M to the integrated object P. It is configured to be able to.
The upper end portion of the YATCO Y is configured as a small-diameter portion Y1 that can be attached to and detached from the drive shaft Ma of the rotary drive device M, and the lower end portion of the YATCO Y is a large that can be engaged with the jig body 4b of the jig 4 to be engaged. The diameter Y2 is configured.
In addition, an engagement recess Y2a having a “key shape” that can be engaged with an engagement protrusion 4c formed on the jig body 4b is formed at the lower edge of the large diameter portion Y2.

Therefore, the jig Y attached to the upper end of the unitary object P is covered with the Y-tack Y from above, and is lowered so that the engagement protrusion 4c enters the engagement recess Y2a. By rotating the Y-cots Y until the engaging protrusions 4c come into contact with the portions, the Y-cos Y can be engaged and connected to the frame pillar 1, and the rotational driving force of the rotational driving device M is transmitted to the integrated object P. become able to.
In addition, by lowering the rotation driving device M by a pile driving device not shown in the drawing, the integrated object P can be built in the ground G while rotating.

Next, a construction method of the structural stem 1 will be described.
[1] As shown in FIG. 1, for example, an auger machine or the like is used to dig the erection hole 5 at a position where the integrated object P is to be installed, and a cement liquid for rooting is injected.
[2] In the state where most of the prefabricated pile 2 of the monolith P is built in the hole 5 for erection, the lower end of the built-up pillar 1 is connected to the hollow portion V of the prefabricated pile 2 as shown in FIG. The built-up pillar 1 and the ready-made pile 2 are integrally connected through the grooved steel 3 by welding.
[3] Engage the jig Y in the engaged jig 4 attached to the upper end of the structural pillar 1 and use the rotational drive by the rotational drive device M, while the integral object P is installed in the mounting hole 5 (See FIG. 3).
[4] After the monolith P is built at a predetermined depth, the Y-tack Y is removed from the structural pillar 1 and the engaged jig 4 is removed (see FIG. 4).

Through the above process, the structural pillar 1 can be installed in the ground.
Further, when the construction of the foundation beam B0b and the main pillar B0a in the underground part B0 is completed while supporting the load from the ground part B1 by the structural pillar 1, the load support in the structural pillar 1 is The removal of the part 1B to be removed from the true pillar 1 will be described below.
[1] As shown in FIG. 7, with respect to the short H-section steel 1Ba on the upper end side of the removal target portion 1B, only the short H-section steel 1Ba is shifted in the lateral direction with the bolt connection at the upper and lower ends being released. Remove.
Subsequently, the short H-section steel 1Bb on the lower end side of the removal target portion 1B is removed with the bolt connection at the lower end portion released.
[2] As shown in FIG. 8, the structural pillar 1 is removed in a state where the embedded target portion 1 </ b> A of the structural pillar 1 is left in the foundation beam B <b> 0 b, and the covering of the portion exposed on the surface is covered. Do.

  With the above process, the construction pillar 1 in the underground part B0 can be removed.

According to the construction pillar construction method of the present embodiment, it becomes possible to build the one-piece P using a compact and light Yatco Y compared to the conventional one, and the handling efficiency is improved. Improvements can be achieved, and the construction period reduction and cost reduction associated therewith can be realized.
When the monolith P is built, it is possible to directly measure the verticality of the structural pillar 1 portion, and the monolith P can be built with high vertical accuracy.
Also, when removing the target part 1B of the structural pillar 1, the axial force can be easily released and extracted by applying a lateral force by constricting the short H-section steel 1Ba, and a narrow underground work space Even so, the structural pillar 1 can be removed efficiently without interfering with the surroundings.
Furthermore, since a temporary general-purpose product is used for the H-shaped steel of the removal target portion 1B, it is easy to divert and use it, and it is possible to reduce costs.

[Another embodiment]
Other embodiments will be described below.

<1> The built-up pillar 1 and the ready-made pile 2 which comprise the integral object P are not restricted to what was demonstrated by previous embodiment, For example, the built-up pillar 1 is replaced with H-section steel, and is cylindrical. It may be steel (square tube or cylinder), cross-section steel or the like. Moreover, the ready-made pile 2 is not restricted to a PHC pile, A PC pile, RC pile, etc. may be sufficient.

<2> The structural pillar 1 is not limited to the one provided with the removal target portion 1B described in the previous embodiment. For example, the full pillar 1 may be incorporated into the main pillar without being removed.

<3> As described in the previous embodiment, assembling the monolith P into the erection hole 5 is performed by connecting the structural pillar 1 to the ready-made pile 2 that has been partially erected. However, it is not limited to the method of constructing the one-piece P after it is lowered by applying a rotational force to the one-piece P. For example, the ready-made pile 2 and the built-up pillar 1 are integrally connected in advance on the ground. In a state in which P is configured, it may be built while rotating the integral object P in the erection hole 5.

  In addition, as mentioned above, although the code | symbol was written in order to make contrast with drawing convenient, this invention is not limited to the structure of an accompanying drawing by this entry. In addition, it goes without saying that the present invention can be carried out in various modes without departing from the gist of the present invention.

1 True column 1B Removal target part 1Ba Short H-section steel (an example of short section steel)
1Bb short H-section steel (an example of short section steel)
2 Ready-made piles B0a Permanent pillar G Ground P Integral X Axis Y Yatco

Claims (3)

It is a construction pillar construction method that builds an integrated body of ready-made piles and construction pillars into the ground while rotating around the axis using a Yatco,
The Yatco is connected to the structural pillar to transmit rotational force ,
The construction pillar construction method, wherein the construction pillar is provided with a removal target part that is removed after completion of the main pillar. At least part of the length of the previous SL removal target part,構真column construction method according to claim 1 that incorporates the separation freely short section steel.   The construction method of a erection pillar according to claim 2, wherein the short steel is composed of a general-purpose product for temporary use in which a plurality of bolt holes are formed at predetermined intervals.

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