Method for building in reverse striking struts and yatco used therefor

Abstract

To provide a method for constructing an under-ground piled column and a pile follower capable of easily preventing the under-ground piled column from floating due to buoyancy.SOLUTION: A method of constructing an under-ground piled column, which is constructed in a hole provided in the ground, comprises steps of: inserting the under-ground piled column with a pile follower 10 attached to the upper end into the hole; and pouring concrete into the hole with the pile follower 10 attached to the upper end of the under-ground piled column and fixing an embedded portion of the under-ground piled column to the concrete pile. The method for constructing the under-ground piled column and the pile follower 10 are characterized by using the pile follower 10 having a main body portion 11 formed in a hollow columnar shape from a steel pipe and a cement hardened portion 16 placed inside the main body portion 11.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a method for installing a counter-punching column and a yatco used therefor.

Background Art

[0002] As a construction method for constructing a building having a ground portion and an underground portion, a counter-punching method is known. In the counter-punching method, before excavating the ground to construct the underground structure, a counter-punching column for supporting the ground portion of the building is provided in the ground and built into a hole, so that while excavating the ground to construct the underground structure, the construction of the ground portion on the counter-punching column can be carried out in parallel. Thereby, compared with the construction method in which the construction of the ground portion is advanced after the construction of the underground portion is completed, the construction period of the building can be shortened. Hang In such a counter-punching method, after the counter-punching column is inserted into the hole, the counter-punching column is fixed to the cast-in-place concrete pile at the root portion by casting concrete into the hole (pre-insertion method), or after the concrete is cast into the hole, the counter-punching column is inserted into the concrete to be fixed to the cast-in-place concrete pile at the root portion (post-insertion method). However, until the concrete cast into the hole hardens, buoyancy acts on the counter-punching column, so there is a risk that the counter-punching column will float due to the buoyancy and cause displacement such as a decrease in verticality.

[0003] In response to such a problem, conventionally, when installing a counter-punching column in a hole provided in the ground, a method has been proposed in which clear water (tap water) is filled inside the counter-punching column to increase the weight of the counter-punching column and prevent the counter-punching column from floating due to buoyancy (see, for example, Patent Document 1). Hang After being inserted into the hole Hang The counter-punching column is fixed to the cast-in-place concrete pile at the root portion by casting concrete into the hole (pre-insertion method), or Hang After the concrete is cast into the hole, the counter-punching column is inserted into the concrete to be fixed to the cast-in-place concrete pile at the root portion (post-insertion method). However, Hang Until the concrete cast into the hole hardens, buoyancy acts on the counter-punching column, so there is a risk that the counter-punching column will float due to the buoyancy and cause displacement such as a decrease in verticality.

[0004] In response to such a problem, conventionally, when installing a counter-punching column in a hole provided in the ground, Hang a method has been proposed in which clear water (tap water) is filled inside the counter-punching column to increase the weight of the counter-punching column and prevent the counter-punching column from floating due to buoyancy (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] However, in the above conventional method, Hang after the concrete placed in the hole has hardened and the counter-punching support is fixed to the concrete pile, it is necessary to remove clear water from the inside of the counter-punching support, and there is a problem that the operation is complicated.

[0007] The present invention has been made in view of the above problems, and an object thereof is to provide a method for constructing a counter-punching support and a yatco that can easily prevent the counter-punching support from floating due to buoyancy.

Means for Solving the Problems

[0008] The method for constructing a counter-punching support of the present invention is a method for constructing a counter-punching support by building a counter-punching support into an anti-hole provided in the ground, and includes a step of inserting the counter-punching support with a yatco attached to the upper end into the anti-hole, and a step of placing concrete in the anti-hole while the yatco is attached to the upper end of the counter-punching support to fix the root portion of the counter-punching support to the concrete pile. As the yatco, a main body portion formed in a hollow columnar shape by a steel pipe, and a cement hardened portion placed inside the main body portion, are included and the cement hardened part is filled inside the main body before hardening and integrated with the main body by hardening inside the main body and it is characterized by using such a thing.

[0009] The yatco of the present invention A method of building a reverse batter strut in a ground hole provided in the ground, the method comprising: a step of previously placing concrete in the ground hole; inserting the reverse batter strut having a yatco attached to the upper end into the ground hole, and fixing the root portion of the reverse batter strut to a concrete pile while the yatco is attached to the upper end of the reverse batter strut. The yatco has a main body portion formed in a hollow columnar shape by a steel pipe and a cement hardened part placed inside the main body portion. The cement hardened part is filled inside the main body before hardening and integrated with the main body by hardening inside the main body is characterized by this.

Effects of the Invention

[0010] According to the present invention, it is possible to provide a method for constructing a counter-punching support and a yatco that can easily prevent the counter-punching support from floating due to buoyancy.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Embodiments for Carrying Out the Invention

[0012] Hereinafter, the method of installing a reverse-striking column and the yatco according to an embodiment of the present invention will be exemplified and described in detail with reference to the drawings.

[0013] The reverse-striking column 1 shown in FIG. 1 is to be built into a Hang hole provided in the ground in the method of installing a reverse-striking column according to an embodiment of the present invention.

[0014] The reverse jacking support 1 is formed into a straight columnar shape with a predetermined length by a steel pipe having a rectangular cross section. The inside of the reverse jacking support 1 is hollow. A plurality of studs 2 for locking the reverse jacking support 1 to a mat slab constituting an underground structure are arranged and fixed at predetermined intervals in the vertical and horizontal directions on the outer peripheral surface of the lower side portion of the reverse jacking support 1. In FIG. 1, for the sake of convenience, only one stud 2 is labeled. The portion below the portion where the plurality of studs 2 of the reverse jacking support 1 are fixed is the embedding portion 3. The embedding portion 3 is the portion of the reverse jacking support 1 that Hang is inserted into the concrete placed in the hole and fixed to the concrete pile after the concrete has hardened.

[0015] In the present embodiment, the reverse jacking support 1 is configured such that the entire portion from the upper end to the lower end is formed by a steel pipe having a rectangular cross section. However, for example, the shape or configuration thereof can be appropriately changed, such as a configuration in which the upper side portion is formed by a steel pipe having a rectangular cross section and the lower side portion is formed by a so-called cross H-shaped steel.

[0016] When the reverse jacking support 1 is erected in a hole provided in the ground, Hang a yatco (temporary pile) 10 according to an embodiment of the present invention is attached to the upper end thereof.

[0017] As shown in FIGS. 2 and 3, the yatco 10 has a main body portion 11 formed into a straight and hollow columnar shape with a predetermined length by a steel pipe having a rectangular cross section having the same dimensions as the reverse jacking support 1. At the lower end of the main body portion 11 of the yatco 10, it is fixed to the upper end of the reverse jacking support 1 so as to be coaxial with each other and the four sides overlap vertically. The attachment structure of the yatco 10 to the upper end of the reverse jacking support 1 can adopt various structures as long as the yatco 10 can be detachably attached to the reverse jacking support 1, such as a structure in which a connecting plate 20 is fixed and connected to flanges (not shown) provided on the outer peripheral surface of the upper end portion of the reverse jacking support 1 and the outer peripheral surface of the lower end portion of the yatco 10 with bolts 21.

[0018] At the lower end of the main body portion 11, a lower end closing wall 12 that closes the lower end of the main body portion 11 is fixed, and at the upper end of the main body portion 11, an upper end closing wall 13 that closes the upper end of the main body portion 11 is fixed. On the upper surface of the upper end closing wall 13, a pair of hanging hooks 14 are fixed. Further, on the outer peripheral surface of the main body portion 11, a plurality of blade-shaped stoppers 15 are fixed to prevent the Hang yatto 10 from falling into the hole.

[0019] The yatto 10 of the present embodiment has a cement hardened portion 16 placed inside the main body portion 11. That is, the yatto 10 of the present embodiment has a configuration in which the inside of the main body portion 11 formed in a hollow column shape by a steel pipe is filled with the cement hardened portion 16. The cement hardened portion 16 is filled inside the main body portion 11 before hardening and is integrated with the main body portion 11 by hardening inside the main body portion 11. With such a configuration, the yatto 10 of the present embodiment is heavier than a conventional yatto with a hollow inside.

[0020] The cement hardened portion 16 is obtained by mixing cement with a liquid such as water and aggregate and hardening it. As the cement hardened portion 16, for example, concrete obtained by mixing cement with sand (fine aggregate), gravel (coarse aggregate), and a liquid such as water and hardening it, mortar obtained by mixing cement with sand (fine aggregate) and a liquid such as water and hardening it, or soil cement obtained by mixing cement with soil (fine aggregate) and a liquid such as water and hardening it can be used. Note that the cement hardened portion 16 may contain various additives in addition to the aggregate and the liquid. Further, the cement hardened portion 16 may be obtained by hardening a mixture of only cement and a liquid such as water without adding aggregate.

[0021] The amount of the cement hardened portion 16 placed inside the main body portion 11 is such that the total weight of the counter-punching support 1 and the yatto 10 is Hang greater than the buoyancy acting on the counter-punching support 1 when the root insertion portion 3 of the counter-punching support 1 is inserted into the concrete placed in the hole.

[0022] Next, when constructing a building having a ground portion and an underground portion by the counter-punching method, by the method of installing the counter-punching columns of the present embodiment, the Hang procedure for installing the counter-punching column 1 into the hole provided in the ground will be described.

[0023] First, as shown in Fig. 4(a), at the planned installation position of the counter-punching column 1 on the ground 30 of the construction site for constructing a building by the counter-punching method, a hole 31 of a predetermined depth is drilled using an excavation device such as a drill. In the illustrated case, Hang the hole 31 is drilled. The shape of the hole is cylindrical with an enlarged diameter only at the bottom, but the shape can be changed as appropriate. Next, as shown in Fig. 4(b), Hang the reinforcing bar 32 is installed at a predetermined position on the bottom side of the hole 31. Hang

[0024] Hang Next, as shown in Fig. 5(a), the counter-punching column 1 with the yatco 10 attached to the upper end at the construction site is suspended by a crane (not shown) using a wire 33 connected to the suspension hook 14 of the yatco 10, and inserted into the hole 31 from the lower end side. At this time, Hang a gantry 34 is installed above the opening of the hole 31, and the counter-punching column 1 and the yatco 10 are guided by the guide rollers 35 provided on the gantry 34 and inserted into the hole 31 in a vertical posture. In addition, a plurality of pantograph-type jacks 36 are attached to positions on the outer peripheral surface of the counter-punching column 1 that face each other across the axis of the counter-punching column 1. Hang Hang

[0025] When the counter-punching column 1 is inserted until its lower end reaches a position at a predetermined depth of the hole 31, the stopper 15 is supported by the gantry 34, and the counter-punching column 1 is held at that position. The vertical position of the counter-punching column 1 is adjusted by the journal jack 37 provided on the gantry 34. Next, the plurality of pantograph-type jacks 36 are opened and Hang the jacks 36 are brought into contact with the wall surface of the hole 31. When the counter-punching column 1 Hang Hang Hang Hang HangIn the state where it is inserted into the hole 31 to a predetermined depth, since the yatco 10 is supported by the guide roller 35, the reverse striking support column 1 is supported in a vertical posture at two locations above and below the jack 36 and the guide roller 35. By adjusting the opening degree of the left and right pantograph type jacks 36 and the position of the guide roller 35, the verticality of the reverse striking support column 1 is appropriately adjusted so as to be within a predetermined range. The measurement of the verticality of the reverse striking support column 1 can be performed using an inclinometer (not shown) attached to the outer peripheral surface of the reverse striking support column 1.

[0026] Next, as shown in Fig. 5(b), Hang With the yatco 10 attached to the upper end of the reverse striking support column 1 inserted into the hole 31, Hang The tremie pipe 38 is built into the hole 31, and through the tremie pipe 38 Hang Concrete 39 is placed inside the hole 31 from the bottom surface to a predetermined height. Hang When the concrete 39 is placed inside the hole 31, the reinforcing bars 32 and the embedding part 3 of the reverse striking support column 1 are embedded inside the concrete 39.

[0027] Hang When the concrete 39 placed inside the hole 31 hardens, the reverse striking support column 1 is fixed to the hardened concrete 39 at the embedding part 3, that is, the concrete pile where the reinforcing bars 32 are embedded.

[0028] By the same procedure, the predetermined number of reverse striking support columns 1 required for the building are fixed to the concrete piles of the predetermined number of Hang holes 31 provided in the ground 30.

[0029] When all the reverse striking support columns 1 are fixed to the corresponding Hang concrete (concrete pile) 39 of the hole 31, Hang After filling the hole 31, as shown in Fig. 6, while proceeding with the work of constructing the above-ground part 40 of the building supported by the reverse striking support column 1, the ground 30 is excavated to a predetermined depth, and concrete is placed from the tremie pipe 38 at the bottom to form a pressure-resistant slab of the underground structure that constitutes the underground part of the building, and the work of constructing the underground part 41 such as this is advanced.

[0030] Here, as shown in FIG. 5(b), Hang After inserting the counter-punching support column 1 into the hole 31, Hang When the concrete 39 is placed inside the hole 31, the counter-punching support column 1 is in a state of being inserted into the internal part of the rooting part 3 before hardening, that is, inside the concrete 39 having fluidity. Therefore, until the concrete 39 hardens, buoyancy acts on the counter-punching support column 1. When the counter-punching support column 1 receives buoyancy from the concrete 39, there is a risk of the counter-punching support column 1 floating up due to the buoyancy and causing displacement such as a decrease in verticality.

[0031] On the contrary, in the method for building in the counter-punching support column of the present embodiment, with the yatco 10 attached to the upper end of the counter-punching support column 1 still in a state Hang while placing the concrete 39 in the hole 31 and using a heavy one with the cement hardened part 16 placed inside the main body part 11 formed in a hollow columnar shape by a steel pipe as the yatco 10, the buoyancy received by the counter-punching support column 1 from the concrete 39 can be offset by the weight of the yatco 10, and the floating up of the counter-punching support column 1 due to buoyancy can be prevented.

[0032] Also, in the method for building in the counter-punching support column of the present embodiment, without filling the inside of the counter-punching support column 1 with fresh water (tap water) as in the conventional method to increase the weight of the counter-punching support column 1, by using the yatco 10 with the cement hardened part 16 placed inside the main body part 11, the floating up of the counter-punching support column 1 due to buoyancy is prevented. Hang After the concrete 39 placed in the hole 31 hardens and the counter-punching support column 1 is fixed to the concrete pile, there is no need for the operation of removing the fresh water from the inside of the counter-punching support column 1. Also, when removing the yatco 10 from the counter-punching support column 1, since the cement hardened part 16 inside the main body part 11 is hardened, the yatco 10 can be easily removed from the counter-punching support column 1 as it is without performing operations such as removing the cement hardened part 16 from the main body part 11.

[0033] Thus, in the method for building in the counter-punching support column of the present embodiment, provided in the ground 30Hang When installing the counter - punching support column 1 into the hole 31, as the yatco 10 attached to the upper end of the counter - punching support column 1, one having a main body portion 11 formed in a hollow columnar shape by a steel pipe and a cement hardened portion 16 placed inside the main body portion 11 is used. Thus, it is possible to easily prevent the counter - punching support column 1 from floating due to buoyancy without performing complicated drainage work or the like.

[0034] Also, by placing the cement hardened portion 16 inside the main body portion 11 to increase the weight of the yatco 10, compared with the case of increasing the weight by making the main body portion 11 a solid structure of steel material, the manufacturing cost of the yatco 10 or the cost required for the installation work of the counter - punching support column 1 can be reduced.

[0035] The present invention is not limited to the above - described embodiments, and it goes without saying that various modifications can be made without departing from the gist thereof.

[0036] For example, in the above - described embodiment, before attaching the yatco 10 to the upper end of the counter - punching support column 1, the cement hardened portion 16 may be placed inside the main body portion 11 in advance. After attaching the main body portion 11 with an empty interior to the upper end of the counter - punching support column 1 and inserting the counter - punching support column 1 Hang into the hole 31, Hang before placing the concrete 39 into the hole 31, the cement hardened portion 16 may be placed inside the main body portion 11. After attaching the main body portion 11 with an empty interior to the upper end of the counter - punching support column 1 and inserting the counter - punching support column 1 Hang into the hole 31, Hang when placing the cement hardened portion 16 inside the main body portion 11 before placing the concrete 39 into the hole 31, if concrete is used as the cement hardened portion 16, Hang the concrete 39 for placing into the hole 31 can be diverted to form the cement hardened portion 16, and the manufacturing cost of the yatco 10 or the cost required for the installation work of the counter - punching support column 1 can be further reduced.

[0037] Also, in the above - described embodiment, the counter - punching support column 1 HangAfter being inserted into the hole 31, Hang concrete 39 is placed in the hole 31 (pre-insertion method), Hang but after concrete 39 is placed in the hole 31 in advance and before the concrete 39 hardens, the reverse-pressing support 1 Hang may be inserted into the hole 31 (post-insertion method).

Explanation of reference numerals

[0038] 1 Reverse-pressing support 2 Stud 3 Embedment part 10 Yatco 11 Body part 12 Lower-end closing wall 13 Upper-end closing wall 14 Hanging hook 15 Stopper 16 Cement hardening part 20 Connecting plate 21 Bolt 30 Ground 31 Hang Hole 32 Reinforcing bar 33 Wire 34 Scaffold 35 Guide roller 36 Jack 37 Journal jack 38 Tremie pipe 39 Concrete 40 Above-ground part 41 Underground part

Claims

1. A method for installing a counter-punching support column into an anti-hole provided in the ground, comprising: inserting the counter-punching support column with a yatco attached to its upper end into the anti-hole; casting concrete into the anti-hole while the yatco is attached to the upper end of the counter-punching support column to fix the root embedding part of the counter-punching support column to a concrete pile; and as the yatco, a main body part formed in a hollow columnar shape by a steel pipe; a cement hardened part cast inside the main body part; and using a structure in which the cement hardened part is filled inside the main body part before hardening and is integrated with the main body part by hardening inside the main body part. The method for installing a counter-punching support column is characterized by this.

2. A method for installing a counter-punching support column into an anti-hole provided in the ground, comprising: casting concrete into the anti-hole in advance; inserting the counter-punching support column with a yatco attached to its upper end into the anti-hole, and fixing the root embedding part of the counter-punching support column to a concrete pile while the yatco is attached to the upper end of the counter-punching support column; and as the yatco, a main body part formed in a hollow columnar shape by a steel pipe; a cement hardened part cast inside the main body part; and using a structure in which the cement hardened part is filled inside the main body part before hardening and is integrated with the main body part by hardening inside the main body part. The method for installing a counter-punching support column is characterized by this.

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