Unbonded precast prestressed concrete columns and precast concrete column bodies

Abstract

To provide an un-bonded precast pre-stressed concrete column excellent in earthquake resistance and high in safety.SOLUTION: An un-bonded precast pre-stressed concrete column includes a plurality of vertically arranged precast concrete columns, tension material inserted into the precast concrete columns in an un-bonded state, and assembly bars embedded in the precast concrete columns, where the assembly bars include a non-adhesion part that does not adhere to the concrete within the precast concrete columns.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] One embodiment of the present invention relates to an unbonded precast prestressed concrete column. Further, one embodiment of the present invention relates to a precast concrete column body for forming an unbonded precast prestressed concrete column.

Background Art

[0002] An unbonded prestressed concrete structure is a structure in which a tendon inserted into a sheath pipe is tensioned (prestressed) with a hydraulic jack or the like. By prestressing, a compressive stress is applied to the concrete, offsetting the tensile stress generated in the concrete by the bending stress due to the dead load and the live load, and realizing a concrete cross-section where no tensile stress occurs.

[0003] Concrete provided with tendons has mainly been used as a beam of a building, but in recent years, its use as a column of a building has been promoted (see, for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] When vibration occurs in a building, a concrete column provided with tendons has excellent seismic resistance because the prestress force is maintained and the tendons can deform over the entire length. On the other hand, if the tendons of the concrete column break, the prestress is not maintained, and there is a risk of significant damage to the building. Therefore, there has been a demand for a concrete column having an unbonded prestressed concrete structure with excellent seismic resistance and high safety.

[0006] In view of the above problems, one of the problems of an embodiment of the present invention is to provide an unbonded precast prestressed concrete column having excellent seismic resistance and high safety.

Means for Solving the Problems

[0007] An unbonded precast prestressed concrete column according to an embodiment of the present invention includes a plurality of precast concrete column bodies arranged in the vertical direction, a tendon inserted through the precast concrete column bodies in an unbonded state, and assembled reinforcement embedded in the precast concrete column bodies. The assembled reinforcement includes a non-adhered portion that does not adhere to the concrete within the precast concrete column body.

[0008] A precast concrete column body according to an embodiment of the present invention is a precast concrete column body that is arranged in a plurality in the vertical direction and forms an unbonded precast prestressed concrete column. It includes a tendon inserted through the concrete in an unbonded state and assembled reinforcement embedded in the concrete. The assembled reinforcement includes a non-adhered portion that does not adhere to the concrete.

[0009] The precast concrete column body includes a joint portion joined to a beam, and the non-adhered portion may be provided at least in a part of the joint portion.

[0010] The assembled reinforcement may be covered with a covering material at the non-adhered portion.

[0011] The covering material may be an elastic body.

[0012] The covering material may be clay, vinyl tape, or butyl rubber.

[0013] The unbonded precast prestressed concrete column further includes lateral reinforcement bars embedded in the precast concrete column body, and the lateral reinforcement bars may be in contact with the covering material.

[0014] The tension member may be provided inside the assembly bars.

[0015] The assembly bars may be provided at the four corners of the precast concrete column body.

Advantages of the Invention

[0016] The unbonded precast prestressed concrete column according to an embodiment of the present invention is excellent in safety and seismic resistance.

Brief Description of the Drawings

[0017]

Figure 1

Figure 2

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Figure 8

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Figure 10

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Figure 15

Mode for Carrying Out the Invention

[0018] Hereinafter, each embodiment of the present invention will be described with reference to the drawings. It should be noted that the embodiments are merely examples, and those that can be easily conceived by those skilled in the art by appropriately changing while maintaining the gist of the invention are naturally included in the scope of the present invention. In addition, for the purpose of making the explanation clearer, the drawings may schematically represent the width, thickness, shape, etc. of each part compared with the actual aspect. However, the illustrated shape is merely an example and does not limit the interpretation of the present invention.

[0019] In the present specification, for convenience of explanation, terms such as "upper", "above", or "upper part" or "lower", "below", or "lower part" are used for explanation, but it is only explaining the vertical relationship of each component. For example, when explaining the positional relationship of the components of a structure (for example, a concrete column body, etc.), based on the normal use mode of the structure, the ground side in the vertical direction may be regarded as "lower", "below", or "lower part".

[0020] In this specification, the characters "first", "second", "third", or "fourth" appended to each component are for convenience in distinguishing each component and have no further meaning unless otherwise specified.

[0021] In this specification and the drawings, when collectively representing a plurality of identical or similar components, the same reference numerals are used. When separately representing each of these components, uppercase or lowercase alphabets may be appended for representation. Also, when separately representing a plurality of parts within one component, hyphens and natural numbers may be used.

[0022] In this specification, the "assembly bar" refers to a bar whose one end contacts a transverse reinforcing bar arranged at the outermost side of one end side in the longitudinal direction of a precast concrete column body, protrudes from the one end of the precast concrete column body, and whose other end protrudes into a recess provided on the other end side of the precast concrete column body. Also, in one precast concrete column body, among the plurality of transverse reinforcing bars arranged in the longitudinal direction within the precast concrete column body, it includes a bar that contacts the transverse reinforcing bar arranged at the outermost side of one end side of the precast concrete column body and is provided in contact with the transverse reinforcing bar arranged at the outermost side of the other end side.

[0023] The following embodiments can be combined with each other as long as no technical contradiction occurs.

[0024] <First Embodiment> Referring to FIGS. 1 to 8, an unbonded precast prestressed concrete column 20 according to an embodiment of the present invention will be described.

[0025] [1. Configuration of Unbonded Precast Prestressed Concrete Column 20] FIG. 1 is a schematic view of a building 10 including an unbonded precast prestressed concrete column 20 according to an embodiment of the present invention. As shown in FIG. 1, the building 10 includes an unbonded precast prestressed concrete column 20 extending in the vertical direction and a concrete beam 30. In other words, the building 10 is a structure including an unbonded precast prestressed concrete column 20 and a concrete beam 30. The unbonded precast prestressed concrete column 20 has a configuration in which a plurality of precast concrete column bodies 100 are arranged in the vertical direction and are joined at a joint portion 200. Further, the concrete beam 30 is joined to the precast concrete column body 100 at a joint portion 300. The position of the joint portion 300 is not particularly limited, and the joint portion 300 may be provided in any of the precast concrete column bodies 100.

[0026] Although not shown, a slab is provided in the range surrounded by the concrete beam 30. However, in the case of a through structure or the like, there may be a floor in the building 10 where the slab is not provided.

[0027] FIG. 2 is a schematic view showing a joint portion 200 and a joint portion 300 in the unbonded precast prestressed concrete column 20 according to an embodiment of the present invention.

[0028] As shown in FIG. 2, the two precast concrete column bodies 100 are joined at the joint portion 200. Details of the joining of the precast concrete column bodies 100 will be described later. Further, the concrete beam 30 is joined to the precast concrete column body 100 at the joint portion 300.

[0029] Each of the plurality of precast concrete column bodies 100 includes a plurality of assembled reinforcing bars 110, a plurality of tendons 121, and a plurality of lateral reinforcing bars 130. The assembled reinforcing bars 110 are embedded in the precast concrete column body 100, and the tendons 121 are inserted through the precast concrete column body 100 in an unbonded state. Further, the lateral reinforcing bars 130 are embedded in the concrete of the precast concrete column body 100 so as to surround the plurality of assembled reinforcing bars 110 in a plane substantially perpendicular to the extending direction of the assembled reinforcing bars 110.

[0030] The assembled reinforcing bars 110 embedded in the precast concrete column body 100 are adhered to the concrete constituting the precast concrete column body 100. However, the unbonded precast prestressed concrete column 20 has an unadhered portion 310 where the assembled reinforcing bars 110 are not adhered to the concrete of the precast concrete column body 100. For example, as shown in FIG. 2, the unadhered portion 310 can be provided in the joint portion 300. In the building 10 using the unbonded precast prestressed concrete column 20, even if the tendon 121 breaks, at least one of the plurality of assembled reinforcing bars 110 connects the precast concrete column bodies 100 stacked together, so that the building 10 can be supported. However, if the assembled reinforcing bars 110 are adhered to the concrete, local strain may occur in the assembled reinforcing bars 110 during an earthquake, and tensile yielding may occur. That is, although it is an unbonded precast prestressed concrete column in which residual deformation is unlikely to occur, there is a possibility that residual deformation remains, similar to a reinforced concrete column. In the unbonded precast prestressed concrete column 20, the assembled reinforcing bars 110 have the unadhered portion 310, which suppresses the occurrence of local strain in the assembled reinforcing bars 110 in the unadhered portion 310 and makes tensile yielding less likely to occur. Therefore, by using the unbonded precast prestressed concrete column 20, it is possible to make the residual deformation of the building 10 after an earthquake less likely to occur. The unadhered portion 310 is preferably provided at the column-beam joint portion (joint portion 300) where tensile yielding is likely to occur during an earthquake, but it can also be provided outside the joint portion 300.

[0031] In the unbonded portion 310, the assembly bars 110 are covered by the covering material 115, and the assembly bars 110 and the concrete are not adhered. Also, when the lateral reinforcement bars 130 are provided in the unbonded portion 310, the lateral reinforcement bars 130 are provided from above the covering material 115 and may be in contact with the covering material 115.

[0032] As the covering material 115, for example, clay, vinyl tape, butyl rubber, etc. can be used, but it is not limited thereto. The covering material 115 only needs to be able to prevent the adhesion between the assembly bars 110 and the concrete.

[0033] FIG. 3 is a schematic cross-sectional view of the joint portion 300 of the unbonded precast prestressed concrete column 20 according to an embodiment of the present invention. Specifically, FIG. 3 is a cross-sectional view of the unbonded portion 310 of the precast concrete column body 100 cut substantially perpendicular to the vertical direction along the line A-A' shown in FIG. 2.

[0034] In a plane substantially perpendicular to the vertical direction, twelve assembly bars 110 are provided in the precast concrete column body 100. The assembly bars 110 are preferably provided at the four corners of the precast concrete column body 100. One end of the four assembly bars 110 located at the four corners of the precast concrete column body 100 is inserted into another precast concrete column body 100 and fixed to the assembly bars 110 of the other precast concrete column body 100 as shown in FIG. 2. That is, the four assembly bars 110 located at the four corners of the precast concrete column body 100 are provided straddling the two precast concrete column bodies 100 to be joined. On the other hand, the ends of the eight assembly bars 110 located on the sides of the precast concrete column body 100 are embedded in the precast concrete column body 100. Note that the number of the assembly bars 110 is not limited to twelve and can be appropriately provided.

[0035] As described above, in the non - adhered portion 310, since the assembly reinforcement 110 is covered by the covering material 115, it is not adhered to the concrete of the precast concrete column body 100. Also, although the lateral reinforcement 130 is provided outside the assembly reinforcement 110, in the non - adhered portion 310, since the assembly reinforcement 110 is covered by the covering material 115, the assembly reinforcement 110 is not in contact with the lateral reinforcement 130. Note that it is preferable to provide the non - adhered portion 310 in the longitudinal direction of the assembly reinforcement 110 with a length equal to or greater than the length of the column body from the upper and lower surfaces of the joint portion 300. Therefore, a plurality of non - adhered portions 310 may be provided in the longitudinal direction of the assembly reinforcement 110. However, in the joint portion 300 (column - beam joint) where columns are provided vertically, the assembly reinforcement 110 of the lower column and the assembly reinforcement 110 from the upper column may overlap, and the non - adhered portion 310 may have a length substantially equal to the length of the beam body. In other words, it is preferable to provide the non - adhered portion 310 with a length equal to or greater than the length of the beam body.

[0036] Also, eight tendons 121 are provided in the precast concrete column body 100. The eight tendons 121 are provided inside the assembly reinforcement 110. The eight tendons 121 are prevented from adhering to the concrete of the precast concrete column body 100 by a sheath pipe described later and are in an unbonded state. Note that the number of tendons 121 is not limited to eight and can be provided as appropriate.

[0037] Note that the positions of the assembly reinforcement 110 and the tendons 121 in the precast concrete column body 100 are not limited to the configuration shown in FIG. 3. In the precast concrete column body 100, the assembly reinforcement 110 may be provided inside the tendons 121.

[0038] [2. Joint of the precast concrete column body 100] FIG. 4 is a schematic diagram for explaining the joint of the precast concrete column body 100 of the unbonded precast concrete column according to an embodiment of the present invention.

[0039] As shown in FIG. 4, the precast concrete column body 100 includes concrete, assembled reinforcement 110, and a tendon 121. At one longitudinal end side (the first end 101-1 side) of the precast concrete column body 100, one end of the assembled reinforcement 110 and one end of the tendon 121 protrude from the first end 101-1. The length of the assembled reinforcement 110 protruding from the first end 101-1 is preferably about 100 mm or more and 500 mm or less. On the other hand, on the other end side of the precast concrete column body 100 (the second end 101-2 side, which is the opposite side of the first end 101-1), a first recess 102-1 and a second recess 102-2 are provided. The depth of the first recess 102-1 and the depth of the second recess 102-2 are not particularly limited, but the depth of the second recess 102-2 is preferably 200 mm or more and 800 mm or less. As shown in FIG. 3, the depth of the first recess 102-1 may be deeper or shallower than the depth of the second recess 102-2.

[0040] A connecting sheath pipe 270 is embedded in the first recess 102-1, and a sleeve 210 is embedded in the second recess 102-2. Inside the connecting sheath pipe 270, the other end of the tendon 121 is provided so as to protrude. Also, inside the sleeve 210, the other end of the assembled reinforcement 110 is provided so as to protrude. Note that the other end of the assembled reinforcement 110 and the other end of the tendon 121 are located inside the precast concrete column body 100 in the longitudinal direction relative to the second end 101-2. In other words, the length of the tendon 121 protruding from the precast concrete column body 100 into the first recess 102-1 is shorter than the length of the first recess 102-1. The length of the assembled reinforcement 110 protruding from the precast concrete column body 100 into the second recess 102-2 is shorter than the length of the second recess 102-2. The length of the assembled reinforcement 110 protruding into the second recess 102-2 is preferably about 100 mm or more and 400 mm or less.

[0041] The unbonded precast prestressed concrete column 20 is formed by press-bonding the second end 101-2 of one precast concrete column body 100 and the first end 101-1 of another precast concrete column body 100 in the vertical direction to form a joint 200. Specifically, the tendon 121 is prestressed so that a plurality of precast concrete column bodies 100 are press-bonded to each other. Further, at the joint 200 of the unbonded precast prestressed concrete column 20, one end of the assembly bar 110 protruding from one precast concrete column body 100 is inserted and fixed into the sleeve 210 of the precast concrete column body 100 adjacent in the vertical direction. That is, the unbonded precast prestressed concrete column 20 includes the assembly bar 110 and the tendon 121 provided across two precast concrete column bodies 100 to be joined. In this way, the unbonded precast prestressed concrete column 20 is composed of n (n is a natural number) precast concrete column bodies 100 press-bonded together. Note that after prestress is introduced into the tendon 121, grout is not injected between the tendon 121 and the connecting sheath pipe 270.

[0042] Hereinafter, for convenience, there may be a case where it is described that the second precast concrete column body 100-2 is located on the first precast concrete column body 100-1. However, when the first precast concrete column body 100-1 and the second precast concrete column body 100-2 are not particularly distinguished, it will be described as the precast concrete column body 100. Further, hereinafter, for convenience, a configuration in which the tendon 121 is inserted into the sheath pipe will be described as a PC member. Although details will be described later, in the PC member, the tendon is arranged in an unbonded state (a state in which a gap is provided between the outer peripheral surface of the tendon and the inner peripheral surface of the sheath pipe). In other words, the tendon 121 of the PC member is not in direct contact with the concrete of the unbonded precast prestressed concrete column 20.

[0043] In addition, the unbonded state in the present embodiment not only includes a state where the tendon 121 is not in contact with the concrete of the unbonded precast prestressed concrete column 20 from the beginning. For example, even if the outer peripheral surface of the tendon 121 is processed smoothly like a mirror surface, the gap between the outer peripheral surface of the tendon 121 and the inner peripheral surface of the sheath pipe is filled with grout, and the outer peripheral surface of the PC member is joined and integrated with the inner peripheral surface of the sheath pipe through the grout in a state where no vibration occurs in the building, when vibration occurs in the building, the joint is released and the tendon can freely deform in the longitudinal direction within the sheath pipe. That is, the unbonded state in the present embodiment means a state where the tendon 121 can freely deform in the longitudinal direction inside the unbonded precast prestressed concrete column 20 when vibration occurs in the building.

[0044] With reference to FIGS. 5 and 6, the configuration of the joint 200 of the precast concrete column body 100 will be described in more detail.

[0045] FIG. 5 is a schematic diagram showing the joint 200 of the unbonded precast prestressed concrete column 20 according to an embodiment of the present invention. FIG. 6 is a cross-sectional view of the PC member 120 of the unbonded precast prestressed concrete column 20 according to an embodiment of the present invention. Specifically, FIG. 6(A) is a cross-sectional view of the PC member 120 cut along the line B-B' shown in FIG. 5, and FIG. 6(B) is a cross-sectional view of the PC member 120 cut along the line C-C' shown in FIG. 5.

[0046] The first precast concrete column body 100-1 includes a plurality of first assembled steel bars 110-1 and a plurality of first tendons 121-1. The second precast concrete column body 100-2 includes a plurality of second assembled steel bars 110-2 and a plurality of second tendons 121-2. Hereinafter, when the first assembled steel bar 110-1 and the second assembled steel bar 110-2 are not particularly distinguished, they will be described as the assembled steel bar 110. Similarly, when the first tendon 121-1 and the second tendon 121-2 are not particularly distinguished, they will be described as the tendon 121.

[0047] As shown in FIG. 5, the first PC member 120-1 includes a first tension member 121-1 and a first sheath tube 122-1. The second PC member 120-2 includes a second tension member 121-2 and a second sheath tube 122-2. Hereinafter, when the first PC member 120-1 and the second PC member 120-2 are not particularly distinguished, they will be described as the PC member 120. Similarly, when the first sheath tube 122-1 and the second sheath tube 122-2 are not particularly distinguished, they will be described as the sheath tube 122.

[0048] Also, as shown in FIG. 5, the joint portion 200 includes a sleeve 210, grout 220, a coupler 230, a bearing plate 240, a washer 250, a nut 260, a connecting sheath tube 270, a bellows sheath tube 275, an increaser 278, and grease 280.

[0049] The sleeve 210 is embedded in the second precast concrete column body 100-2. The end of the second assembled reinforcement 110-2 is provided in the sleeve 210, and the end of the first assembled reinforcement 110-1 is inserted into the sleeve 210. Further, the sleeve 210 is filled with grout 220 and has been cured. Therefore, the end of the first assembled reinforcement 110-1 and the end of the second assembled reinforcement 110-2 are fixed by the grout 220 within the sleeve 210.

[0050] The sleeve 210 is a joint that can fix the assembled reinforcement 110 by filling it with grout. Therefore, the sleeve 210 is provided with an injection port and a discharge port for injecting grout (not shown in FIG. 4). The injection port and the discharge port of the sleeve 210 will be described later together with the description of the injection of grout.

[0051] One end of the sleeve 210 with the end of the second assembling rib 110-2 protruding therefrom is preferably closed. For example, the second assembling rib 110-2 provided in the sleeve 210 and one end of the sleeve 210 may be adhered using a sealing material to close one end of the sleeve 210. On the other hand, the other end of the sleeve 210 is open. Therefore, the grout 220 injected into the sleeve 210 enters the gap between the first precast concrete column body 100-1 and the second precast concrete column body 100-2 from the other end of the sleeve 210.

[0052] The grout 220 can be, for example, a cement-based grout material such as mortar, a glass-based grout material such as water glass, or a synthetic resin-based grout material such as epoxy resin.

[0053] Before hardening, the grout 220 preferably has appropriate fluidity so as to be easily injected into the sleeve 210. On the other hand, after hardening, the grout 220 preferably retains high strength. As the grout 220 used for the unbonded precast prestressed concrete column 20 of the building 10, mortar is preferred. Mortar contains cement. As the cement, for example, Portland cement can be used.

[0054] The connecting sheath pipe 270 is embedded in the first recess 102-1 (see FIG. 2) of the second precast concrete column body 100-2. The end of the second tendon 121-2 is provided in the connecting sheath pipe 270, and the end of the first tendon 121-1 is inserted into the connecting sheath pipe 270. Also, the connecting sheath pipe 270 is filled with grease 280.

[0055] One end of the connecting sheath pipe 270 provided with the end of the second tendon 121-2 is preferably closed so that the filled grease 280 does not leak. As shown in FIG. 5, one end of the connecting sheath pipe 270 is capped by an increaser 278. On the other hand, the other end of the connecting sheath pipe 270 is also preferably closed to prevent the grout 220 from entering. As shown in FIG. 5, a bellows sheath pipe 275 may be provided at the other end of the connecting sheath pipe 270 to close the space between the connecting sheath pipe 270 and the bearing plate 240.

[0056] The configuration of the other end of the connecting sheath pipe 270 is not limited to this. The configurations of one end and the other end of the connecting sheath pipe 270 may be any configuration that can prevent the grease 280 from leaking out and prevent the contact between the first tendon 121-1 and the grout 220. For example, one end of the connecting sheath pipe 270 and the second sheath pipe 122-2 may be adhered using a sealing material to close one end of the connecting sheath pipe 270. Also, the other end of the connecting sheath pipe 270 and the bearing plate 240 may be adhered using a sealing material. Further, instead of the sealing material, mortar may be used. By preventing the grout 220 from entering the connecting sheath pipe 270, the contact between the first tendon 121-1 and the second tendon 121-2 and the grout 220 can be prevented. Also, by preventing the contact with the grout 220, the corrosion of the first tendon 121-1 and the second tendon 121-2 can be suppressed.

[0057] As shown in FIG. 6(B), the PC member 120 includes a tendon 121, a sheath pipe 122, and a protective layer (sheath) 123. The protective layer 123 has a function of protecting the tendon 121 from external water and oxygen. That is, the corrosion of the tendon 121 can be prevented by the protective layer 123. Therefore, the durability of the PC member 120 is improved. The material of the protective layer 123 is, for example, an organic resin such as polyethylene. Note that the protective layer 123 may be composed of a plurality of layers.

[0058] As shown in Fig. 6(A), within the connecting sheath tube 270, the protective layer 123 that covered the tendon 121 is removed. Therefore, grease 280 is filled to prevent corrosion of the tendon 121. Within the connecting sheath tube 270, for the first PC member 120-1, the first sheath tube 122-1 is removed and the first tendon 121-1 is exposed. For the second PC member 120-2 as well, a part of the second sheath tube 122-2 is removed and the second tendon 121-2 is exposed. Also, within the connecting sheath tube 270, the first tendon 121-1 of the first PC member 120-1 and the second tendon 121-2 of the second PC member 120-2 are each screwed to the coupler 230. That is, the first tendon 121-1 of the first PC member 120-1 and the second tendon 121-2 of the second PC member 120-2 are connected via the coupler 230.

[0059] The first tendon 121-1 of the first PC member 120-1 protrudes from the end of the first precast concrete column body 100-1. At the end of the first precast concrete column body 100-1, a bearing plate 240 provided with a through hole is disposed, and the first tendon 121-1 protruding from the end of the first precast concrete column body 100-1 passes through the through hole of the bearing plate 240. Also, the protruding first tendon 121-1 is inserted through a washer 250 disposed on the bearing plate 240 and is screwed by a nut 260 disposed on the washer 250. That is, the exposed first tendon 121-1 of the first PC member 120-1 is screwed to the nut 260, and the end of the first tendon 121-1 is fixed to the end of the first precast concrete column body 100-1.

[0060] The bearing plate 240 is fixed to the concrete of the first precast concrete column body 100-1 and has a function of transmitting the tension of the first tendon 121-1 to the concrete. The size of the bearing plate 240 is preferably larger than the diameter of the first PC member 120-1 and also larger than the diameter of the connecting sheath pipe 270. As shown in FIG. 4, the bearing plate 240 may be provided in the recess of the first precast concrete column body 100-1 or may not be provided in the recess. The shape of the bearing plate 240 is, for example, rectangular, but the configuration of the shape of the bearing plate 240 is not limited to this. The shape of the bearing plate 240 may be, for example, circular.

[0061] For the sheath pipe 122, for example, a steel sheath pipe or a polyethylene sheath pipe can be used, but in the PC member 120, a polyethylene sheath pipe is preferred. Since the polyethylene sheath pipe is resistant to corrosion, the durability of the PC member 120 using the polyethylene sheath pipe for the sheath pipe 122 is improved.

[0062] In FIGS. 2 to 6, the configuration of the unbonded precast prestressed concrete column 20 in which the first assembled bar 110-1 protruding from the first precast concrete column body 100-1 is inserted into the second precast concrete column body 100-2 located above the first precast concrete column body 100-1 has been described. However, it is also possible to adopt a configuration of the unbonded precast prestressed concrete column 20 in which the second assembled bar 110-2 protruding from the second precast concrete column body 100-2 is inserted into the first precast concrete column body 100-1 located below the second precast concrete column body 100-2.

[0063] FIG. 7 is a schematic diagram for explaining the fixing of the assembled bar 110 at the joint 200 of the precast concrete column body 100 of the unbonded precast prestressed concrete column 20 according to an embodiment of the present invention.

[0064] As shown in FIG. 7, the sleeve 210 is provided with an injection port 211 and a discharge port 212 that communicate the space inside the sleeve 210 within the second precast concrete column body 100-2 with the space outside the second precast concrete column body 100-2.

[0065] The injection port 211 and the discharge port 212 are openings for injecting and discharging the grout 220 after the second precast concrete column body 100-2 is installed on the first precast concrete column body 100-1. The grout 220 is injected from the injection port 211, fills the space inside the sleeve 210 and the space between the first precast concrete column body 100-1 and the second precast concrete column body 100-2, and the excess grout 220 is discharged from the discharge port 212. The injection port 211 is provided below the discharge port 212. By positioning the injection port 211 below the discharge port 212, it becomes possible to push out air from below, and the air accumulation in the space can be reduced. However, the injection port 211 can also be provided above the discharge port 212. Also, a plurality of discharge ports 212 can be provided.

[0066] The space between the first precast concrete column body 100-1 and the second precast concrete column body 100-2 is blocked by the backing plate 290 and forms a closed space. Therefore, the injected grout 220 is blocked by the backing plate 290 and does not leak out to the outside of the first precast concrete column body 100-1 and the second precast concrete column body 100-2. The backing plate 290 can be provided outside the first precast concrete column body 100-1 and the second precast concrete column body 100-2 before injecting the grout 220. Note that after the grout 220 hardens, the backing plate 290 can be removed.

[0067] FIG. 8 is a schematic diagram for explaining the connection of the PC member 120 at the joint 200 of the precast concrete column body 100 of the unbonded precast prestressed concrete column 20 according to an embodiment of the present invention.

[0068] As shown in Fig. 8, the connecting sheath pipe 270 is provided with an injection port 271 and a discharge port 272 that communicate the space inside the connecting sheath pipe 270 within the second precast concrete column body 100-2 with the space outside the second precast concrete column body 100-2.

[0069] The injection port 271 and the discharge port 272 are openings for injecting and discharging grease 280 after the first tendon 121-1 of the first PC member 120-1 and the second tendon 121-2 of the second PC member 120-2 are connected by the coupler 230. The grease 280 is injected from the injection port 271, fills the space within the connecting sheath pipe 270, and the excess grease 280 is discharged from the discharge port 272. The injection port 271 is provided above the discharge port 272. However, the injection port 271 can also be provided below the discharge port 272. Also, a plurality of injection ports 271 and discharge ports 272 can be provided.

[0070] Note that the injected grease 280 is blocked by the pressure plate 240 and the bellows sheath pipe 275 in the lower part of the connecting sheath pipe 270, so it will not leak to the outside.

[0071] The above description mainly focuses on the assembly of the unbonded precast prestressed concrete column 20 using the precast method. That is, the precast concrete column body 100 used at the construction site of the building 10 is pre-manufactured in a factory or the like and transported to the construction site of the building 10. The precast concrete column body 100 manufactured in a factory or the like is provided with assembly steel bars 110 and PC members 120 in the concrete. At one end of the precast concrete column body 100, one end of the assembly steel bar 110 and one end of the tendon 121 of the PC member 120 protrude. On the other hand, at the other end of the precast concrete column body 100, a sleeve 210 and a connecting sheath pipe 270 are embedded. Inside the sleeve 210, the other end of the assembly steel bar 110 is provided so as to fit inside the precast concrete column body 100. Inside the connecting sheath pipe 270, the other end of the tendon 121 of the PC member 120 is provided so as to fit inside the precast concrete column body 100. At the construction site of the building 10, a plurality of precast concrete column bodies 100 manufactured in the factory are compression-bonded to form the unbonded precast prestressed concrete column 20. By using the precast method, the working efficiency at the construction site can be improved, the construction period and cost can be shortened, and the constructability can be improved.

[0072] The unbonded precast prestressed concrete column 20 according to this embodiment is an unbonded precast prestressed concrete column 20 in which a first precast concrete column body 100-1 and a second precast concrete column body 100-2 are joined and extend in the vertical direction, and includes a tension member 121 provided across the first precast concrete column body 100-1 and the second precast concrete column body 100-2, and an assembled reinforcement 110 provided across the first precast concrete column body 100-1 and the second precast concrete column body 100-2. Therefore, even when the tension member 121 of the PC member 120 breaks, since the first precast concrete column body 100-1 and the second precast concrete column body 100-2 are connected by the assembled reinforcement 110, the integration of the unbonded precast prestressed concrete column 20 can be maintained. Therefore, the collapse of the building 10 including the unbonded precast prestressed concrete column 20 is suppressed, and the safety of the unbonded precast prestressed concrete column 20 is improved. Further, in the unbonded precast prestressed concrete column 20, since the assembled reinforcement 110 has an unattached portion 310, the generation of local strain of the assembled reinforcement 110 in the unattached portion 310 is suppressed, and tensile yielding is less likely to occur. Therefore, by using the unbonded precast prestressed concrete column 20, the residual deformation of the building 10 after an earthquake can be made less likely to occur.

[0073] <Modification Example 1> Referring to FIG. 9, a joint 200A different from the joint 200 of the unbonded precast prestressed concrete column 20 according to the first embodiment will be described. In the description of the joint 200A, the description may be omitted if it is the same as the configuration of the joint 200.

[0074] FIG. 9 is a schematic cross-sectional view of a joint 200A of an unbonded precast prestressed concrete column 20 according to an embodiment of the present invention. As shown in FIG. 9, the first PC member 120-1 includes a first tendon 121-1 and a first sheath pipe 122-1. The second PC member 120-2 includes a second tendon 121-2 and a second sheath pipe 122-2. Further, the joint 200A includes a sleeve 210A, grout 220, a coupler 230, a bearing plate 240, a washer 250, a nut 260, a connecting sheath pipe 270, a bellows sheath pipe 275, an increaser 278, and grease 280.

[0075] The sleeve 210A is embedded in the first precast concrete column body 100A-1. The end of the first assembly bar 110A-1 is provided inside the sleeve 210A, and the end of the second assembly bar 110A-2 is inserted inside the sleeve 210A. Further, the sleeve 210A is filled with grout 220 and cured. Therefore, the second assembly bar 110A-2 is provided across the first precast concrete column body 100A-1 and the second precast concrete column body 100A-2 and fixed. Although not shown, the first precast concrete column body 100A-1 and the second precast concrete column body 100A-2 include an unattached portion where the first assembly bar 110A-1 or the second assembly bar 110A-2 does not adhere to the concrete.

[0076] In the joint 200A of the unbonded precast prestressed concrete column 20 according to this modification example, the assembly reinforcement 110 is inserted into the end of the first precast concrete column body 100A-1, and the tendon 121 of the PC member 120 is connected at the end of the second precast concrete column body 100A-2. The grout 220 is injected from the end of the first precast concrete column body 100A-1, and the grease 280 is injected from the end of the second precast concrete column body 100-2, and the injection positions of the grout 220 and the grease 280 are different. Therefore, it is possible to reduce the operation error such that the operator injects the wrong injection material. Further, since the positions where the sleeve 210A and the connecting sheath pipe 270 are embedded are dispersed, the strength of the joint 200A is improved.

[0077] <Modification Example 2> Referring to FIG. 10, the precast concrete column body 100B and the joint 200B different from the precast concrete column body 100 of the unbonded precast prestressed concrete column 20 according to the first embodiment will be described. In the description of the precast concrete column body 100B and the joint 200B, the description may be omitted when it is the same as the configuration of the precast concrete column body 100 and the joint 200.

[0078] FIG. 10 is a schematic diagram for explaining the joint of the precast concrete column body 100B according to an embodiment of the present invention.

[0079] As shown in FIG. 10, the precast concrete column body 100B includes auxiliary reinforcement 510B and a tendon 121B. On the side of the first end 101B-1 of the precast concrete column body 100B, one end of the auxiliary reinforcement 510B and one end of the tendon 121B protrude from the first end 101B-1 of the precast concrete column body 100B. On the other hand, on the second end 101B-2 side, which is the opposite side of the first end 101B-1 of the precast concrete column body 100B, a first recess 102B-1 and a second recess 102B-2 are provided. A connecting sheath pipe 270B is provided in the first recess 102B-1, and a sleeve 210B is provided in the second recess 102B-2.

[0080] Inside the connecting sheath pipe 270B, the other end of the tendon 121B is provided so as to protrude. On the other hand, inside the sleeve 210, the other end of the auxiliary reinforcement 510B does not protrude. That is, the other end of the auxiliary reinforcement 510B is embedded in the precast concrete column body 100B.

[0081] The unbonded precast prestressed concrete column 20 is configured by crimping and joining the second end 101B-2 of one precast concrete column body 100B and another precast concrete column body 100B in the vertical direction. At this time, the assembly reinforcement 110B protruding from another precast concrete column body 100B is inserted and fixed into the sleeve 210B provided in one precast concrete column body 100B.

[0082] In the joint 200B of the unbonded precast prestressed concrete column 20 according to this modification example, auxiliary reinforcement 510B is provided. That is, the auxiliary reinforcement 510B is provided straddling the first precast concrete column body 100B-1 and the second precast concrete column body 100B-2. Therefore, even when the tendon 121 breaks, the first precast concrete column body 100B-1 and the second precast concrete column body 100B-2 are connected by the auxiliary reinforcement 510B, and thus the integration can be maintained. Therefore, the safety of the unbonded precast prestressed concrete column 20 according to this modification example is also improved. Further, in the unbonded precast prestressed concrete column 20, the assembled reinforcement 110 has the non-attached portion 310, so that the generation of local strain of the assembled reinforcement 110 in the non-attached portion 310 is suppressed, and tensile yielding is less likely to occur. Therefore, by using the unbonded precast prestressed concrete column 20, the residual deformation of the building 10 after an earthquake can be made less likely to occur.

[0083] <Second Embodiment> Referring to FIGS. 11 and 12, the unbonded precast prestressed concrete column 20C according to an embodiment of the present invention will be described.

[0084] FIG. 11 is a schematic view showing an unbonded precast prestressed concrete column 20C according to an embodiment of the present invention. Further, FIG. 12 is a schematic view showing a joint portion in the unbonded precast prestressed concrete column 20C according to an embodiment of the present invention. Specifically, FIG. 12 is a partially enlarged view of the region A shown in FIG. 11.

[0085] Figures 11 and 12 show two adjacent unbonded precast prestressed concrete columns 20C (the first unbonded precast prestressed concrete column 20C-1 and the second unbonded precast prestressed concrete column 20C-2). The first unbonded precast prestressed concrete column 20C-1 has a configuration in which a first precast concrete column body 100C-1 and a second precast concrete column body 100C-2 are joined at a first joint 200C-1 in the vertical direction. The second unbonded precast prestressed concrete column 20C-2 has a configuration in which a third precast concrete column body 100C-3 and a fourth precast concrete column body 100C-4 are joined at a second joint 200C-2. That is, each of the first unbonded precast prestressed concrete column 20C-1 and the second unbonded precast prestressed concrete column 20C-2 has a configuration in which a plurality of precast concretes are joined. The precast concrete column bodies to be joined may have the same structure or different structures. Also, the first unbonded precast prestressed concrete column 20C-1 and the second unbonded precast prestressed concrete column 20C-2 shown in Figure 11 have different widths of the concrete column bodies, but may have the same structure.

[0086] The first unbonded precast prestressed concrete column 20C-1 and the second unbonded precast prestressed concrete column 20C-2 are joined via a damper 35. Also, a concrete beam 30 is joined to each of the first unbonded precast prestressed concrete column 20C-1 and the second unbonded precast prestressed concrete column 20C-2 on the side opposite to the damper 35. Accordingly, the first unbonded precast prestressed concrete column 20C-1 and the second unbonded precast prestressed concrete column 20C-2 are joined to the concrete beam 30 and the damper 35 at a first joint 300C-1 and a second joint 300C-2, respectively.

[0087] Each of the first joint 300C-1 and the second joint 300C-2 has the same configuration as the above-described joint 300. That is, as shown in FIG. 12, the first joint 300C-1 includes a non-adhered portion 310 where the assembled reinforcement 110 does not adhere to the concrete of the second precast concrete column body 100C-2. Similarly, the second joint 300C-2 includes a non-adhered portion where the assembled reinforcement 110 does not adhere to the fourth precast concrete column body 100C-4.

[0088] In the building 10 using the unbonded precast prestressed concrete column 20C to which the damper 35 is connected, the damper 35 can absorb seismic energy. However, if the assembled reinforcement 110 adheres to the concrete, local strain will occur in the assembled reinforcement 110, resulting in tensile yielding. On the other hand, in the unbonded precast prestressed concrete column 20C having the non-adhered portion 310, the occurrence of local strain in the assembled reinforcement 110 is suppressed, and tensile yielding is less likely to occur. Therefore, by using the unbonded precast prestressed concrete column 20C having the non-adhered portion 310, it is possible to further reduce the residual deformation of the building 10 after an earthquake.

[0089] <Third Embodiment> Referring to FIG. 13, a structure according to an embodiment of the present invention will be described.

[0090] FIG. 13 is a plan sectional view of a structure 12 according to an embodiment of the present invention. Specifically, the structure 12 has a structure combining an unbonded precast prestressed concrete column 20 and a concrete beam 30 included in a building 10, and FIG. 13 is a sectional view cut along a plane substantially perpendicular to the vertical direction and including the concrete beam 30.

[0091] The structure 12 includes an unbonded precast prestressed concrete column 20, a concrete column 21, and a concrete beam 30. Note that the concrete column 21 is an unbonded precast prestressed concrete column, but in this embodiment, it will be described as the concrete column 21 in order to distinguish it from the unbonded precast prestressed concrete column 20. The corner columns and side columns of the structure 12 are composed of unbonded precast prestressed concrete columns 20, and the interior columns of the structure 12 are composed of concrete columns 21. Also, between adjacent unbonded precast prestressed concrete columns 20, between adjacent concrete columns 21, or between an adjacent unbonded precast prestressed concrete column 20 and a concrete column 21, a concrete beam 30 is provided. Note that if the corner columns and side columns of the structure 12 are composed of unbonded precast prestressed concrete columns 20, the number, arrangement, and structure of the unbonded precast prestressed concrete columns 20, concrete columns 21, and concrete beams 30, and the shape of the structure 12 are not limited.

[0092] The unbonded precast prestressed concrete column 20 of this embodiment is the same as the unbonded precast prestressed concrete column 20 described in the first embodiment. That is, in the unbonded precast prestressed concrete column 20 of the structure 12, each of the reinforcing bars and the tendons is provided across two vertically adjacent precast concrete column bodies. Further, the precast concrete column body includes an unattached portion 310 where the assembled reinforcing bars 110 do not adhere to the concrete of the precast concrete column body. On the other hand, in the concrete column 21 of the structure 12, the tendons are provided across two vertically adjacent precast concrete column bodies, but the assembled reinforcing bars are not provided across two vertically adjacent precast concrete column bodies.

[0093] The big difference between corner columns, side columns, and middle columns is the number of concrete beams 30 joined to them. Focusing on one corner column, one side column, and one middle column respectively, two concrete beams 30 are joined to one corner column, three concrete beams 30 are joined to one side column, and four concrete beams 30 are joined to one middle column. If all columns of the structure 12 are made of concrete columns 21, in the unlikely event that the tendons break, the structure 12 may collapse. Therefore, in this embodiment, an unbonded precast prestressed concrete column 20 including not only tendons but also assembled reinforcing bars is applied to the joints of corner columns and side columns. Thereby, even if the tendons of the unbonded precast prestressed concrete column 20 break, since the two precast concrete column bodies are connected by the assembled reinforcing bars, it is possible to maintain the unbonded precast prestressed concrete column 20 as a single entity. Therefore, the collapse of the structure 12 can be prevented and the safety is improved. Further, in the unbonded precast prestressed concrete column 20, since the assembled reinforcing bars 110 have the unattached portion 310, the generation of local strain of the assembled reinforcing bars 110 in the unattached portion 310 is suppressed, and tensile yielding is less likely to occur. Therefore, by using the unbonded precast prestressed concrete column 20, it is possible to make it less likely to generate residual deformation of the building 10 after an earthquake.

[0094] <Modified Example 3> Referring to FIG. 14, a structure 12D different from the structure 12 according to the second embodiment will be described. In the description of the structure 12A, the description may be omitted when it is the same as the configuration of the structure 12.

[0095] FIG. 14 is a plan sectional view of a structure 12D according to an embodiment of the present invention. The structure 12D has a core structure. Here, the core structure refers to a structure in which facilities such as elevators, stairs, machine rooms, or piping are collected to form the core part of a building. Or it refers to a structure in which structural members resistant to seismic forces are concentrated. Note that the core part may be provided over a plurality of floors.

[0096] The structure 12D includes unbonded precast prestressed concrete columns 20, concrete columns 22, dampers 35, concrete beams 30, and reinforced concrete columns 40. The unbonded precast prestressed concrete columns 20 and the concrete columns 22 have different shapes and the like, but both are unbonded precast prestressed concrete columns or wall columns. At least one of the unbonded precast prestressed concrete columns 20 and the concrete columns 22 includes a precast concrete column in which assembled steel bars are crimped and joined across the joint of the precast concrete column body. On the other hand, the reinforced concrete column 40 does not include a tendon. The corner columns and side columns of the structure 12D are composed of reinforced concrete columns 40, and the core part 15 is composed of unbonded precast prestressed concrete columns 20, concrete columns 22, and dampers 35. In the core part 15, the adjacent unbonded precast prestressed concrete column 20 and the concrete column 22 are joined via a damper 35. Also, a concrete beam 30 is joined between the adjacent concrete columns 22.

[0097] Although the unbonded precast prestressed concrete column 20 and the concrete column 22 of the core part 15 are connected to the damper 35, in the unlikely event that the tendon of the unbonded precast prestressed concrete column 20 or the concrete column 22 breaks, the damper 35 is weaker than the concrete beam 30. Therefore, the structure 12D may collapse significantly. However, in this modified example, the core part 15 is constituted by the unbonded precast prestressed concrete column 20 or the concrete column 22 that includes not only tendons but also reinforcing bars at the joint. Therefore, in the unlikely event that the tendon breaks, the first precast concrete column body 100-1 and the second precast concrete column body 100-2 are connected by the assembly bars 110, and the integration of the unbonded precast prestressed concrete column 20 can be maintained. Therefore, the collapse of the structure 12D constituted by the unbonded precast prestressed concrete column 20 and the concrete column 22 can be prevented and the safety is improved. Further, in the unbonded precast prestressed concrete column 20, since the assembly bars 110 have the non-attached part 310, the generation of local strain of the assembly bars 110 in the non-attached part 310 is suppressed, and tensile yielding is less likely to occur. Therefore, by using the unbonded precast prestressed concrete column 20, the residual deformation of the building 10 after an earthquake can be made less likely to occur.

[0098] Furthermore, the unbonded precast prestressed concrete column of the structure may have a configuration in which different types of precast concrete column bodies are combined. The different types of precast concrete column bodies referred to here include a precast concrete column body in which the assembly bars and the tendons protrude from the precast concrete column body, and a precast concrete column body in which the tendons protrude from the precast concrete column body and the assembly bars do not protrude from the precast concrete column body. Therefore, with reference to FIG. 15, a structure 12D different from the structure 12 according to the second embodiment will be described.

[0099] <Modified Example 4> FIG. 15 is a schematic cross-sectional view for explaining a structure 12E according to an embodiment of the present invention. In the description of the structure 12E, when it is the same as the configuration of the structure 12, the description may be omitted.

[0100] The structure 12E may be provided with an unbonded precast prestressed concrete column so as to include precast concrete column bodies of different types for each layer 13D. For example, as shown in FIG. 15(A), the unbonded precast prestressed concrete column 20E includes a first precast concrete column body 100E-1 belonging to the first layer 13E-1, a second precast concrete column body 100E-2 belonging to the second layer 13E-2 adjacent to the first layer 13E-1, a third precast concrete column body 100E-3 belonging to the third layer 13E-3 adjacent to the second layer 13E-2, and a fourth precast concrete column body 100E-4 belonging to the fourth layer 13E-4 adjacent to the third layer 13E-3. In this case, at the joint between the first precast concrete column body 100E-1 and the second precast concrete column body 100E-2 and at the joint between the third precast concrete column body 100E-3 and the fourth precast concrete column body 100E-4, assembly bars 110E and a tension member (not shown) are provided across, and at the joint between the second precast concrete column body 100E-2 and the third precast concrete column body 100E-3, no assembly bars are provided across.

[0101] In addition, different types of precast concrete column bodies 100E may be provided within the structure 12E in the hierarchy 13E. In other words, when a plurality of unbonded precast prestressed concrete columns 20E are provided in the horizontal direction, among the joints of the plurality of precast concrete column bodies 100E provided on the same horizontal plane, it is sufficient if the assembling bars 110E are provided across any one of the joints. For example, as shown in FIG. 15(B), the first unbonded precast prestressed concrete column 20E-1 includes the first precast concrete column body 100E-1 belonging to the first hierarchy 13E-1, the second precast concrete column body 100E-2 belonging to the second hierarchy 13E-2 adjacent to the first hierarchy 13E-1, and the third precast concrete column body 100E-3 belonging to the third hierarchy 13E-3 adjacent to the second hierarchy 13E-2. The second unbonded precast prestressed concrete column 20E-2 includes the fourth precast concrete column body 100E-4 belonging to the first hierarchy 13E-1, the fifth precast concrete column body 100E-5 belonging to the second hierarchy 13E-2, and the sixth precast concrete column body 100E-6 belonging to the third hierarchy 13E-3. In this case, since the assembling bars 110E and the tensioning members (not shown) are provided across the joint between the first precast concrete column body 100E-1 and the second precast concrete column body 100E-2, it is not necessary for the assembling bars to be provided across the joint between the fourth precast concrete column body 100E-4 and the fifth precast concrete column body 100E-5. Since the assembling bars 110E and the tensioning members (not shown) are provided across the joint between the fifth precast concrete column body 100E-5 and the sixth precast concrete column body 100E-6, it is not necessary for the assembling bars to be provided across the joint between the second precast concrete column body 100E-2 and the third precast concrete column body 100E-3. Note that the assembling bars 110E may be auxiliary bars.

[0102] The above-described first unbonded precast prestressed concrete column 20E-1 and the second unbonded precast prestressed concrete column 20E-2 may differ in size, shape, etc. Therefore, for example, in the configuration of the unbonded precast prestressed concrete column 20 and the concrete column 22 of the structure 12D in the above-described modification 3, the configuration of the structure 12E can also be applied.

[0103] Each of the embodiments described above as embodiments of the present invention can be implemented in appropriate combination as long as they do not conflict with each other. Also, based on each embodiment, those in which those skilled in the art have appropriately added, deleted, or changed the design of components, or added, omitted, or changed the conditions of processes, are also included in the scope of the present invention as long as they have the gist of the present invention.

[0104] Even if there are other operational effects different from those brought about by the above-described embodiments, those that are obvious from the description of this specification or can be easily predicted by those skilled in the art are naturally understood to be brought about by the present invention.

Explanation of Reference Numerals

[0105] 10: Building, 12, 12A, 12D, 12E: Structures, 13D, 13E: Floors, 13E-1: First Floor, 13E-2: Second Floor, 13E-3: Third Floor, 13E-4: Fourth Floor, 15: Core Part, 20, 20C, 20E: Unbonded Precast Prestressed Concrete Columns, 20C-1, 20E-1: First Unbonded Precast Prestressed Concrete Column, 20C-2, 20E-2: Second Unbonded Precast Prestressed Concrete Column, 21, 22: Concrete Columns, 30: Concrete Beam, 35: Damper, 40: Reinforced Concrete Column, 100, 100B, 100E: Precast Concrete Column Bodies, 100-1, 100A-1, 100B-1, 100C-1, 100E-1: First Precast Concrete Column Body, 100-2, 100A-2, 100B-2, 100C-2, 100E-2: Second Precast Concrete Column Body, 100C-3, 100E-3: Third Precast Concrete Column Body, 100C-4, 100E-4: Fourth Precast Concrete Column Body, 100E-5: Fifth Precast Concrete Column Body, 100E-6: Sixth Precast Concrete Column Body, 101-1, 101B-1: First End, 101-2, 101B-2: Second End, 102-1, 102B-1: First Recess, 102-2, 102B-2: Second Recess, 110, 110B, 110E: Assembled Reinforcement, 110-1, 110A-1: First Assembled Reinforcement, 110-2, 110A-2: Second Assembled Reinforcement, 115: Coating Material, 120: PC Member, 120-1: First PC Member, 120-2: Second PC Member, 121, 121B: Tension Members, 121-1: First Tension Member, 121-2: Second Tension Member, 122: Sheath Pipe, 122-1: First Sheath Pipe, 122-2: Second Sheath Pipe, 123: Protection Layer, 130: Horizontal Reinforcement, 200, 200A, 200B: Joints, 200C-1: First Joint, 200C-2: Second Joint, 210, 210A, 210B: Sleeves, 211: Inlet, 212: Outlet, 220: Grout, 230: Coupler, 240: Bearing Plate, 250: Washer, 260: Nut, 270, 270B: Connecting Sheath Pipe, 271: Inlet, 272: Outlet, 275: Bellows Sheath Pipe278: Increaser, 280: Grease, 290: Plate, 300: Joint, 300C-1: First joint, 300C-2: Second joint, 310: Unattached part, 510B: Auxiliary rib

Claims

1. A plurality of precast concrete column bodies arranged in the vertical direction, A tension member inserted through the precast concrete column body in an unbonded state, Including assembled reinforcement embedded in the precast concrete column body and extending to a recess provided from one end to the other end side of the precast concrete column body, The assembled reinforcement includes an unadhered portion that does not adhere to the concrete within the precast concrete column body, an unbonded precast prestressed concrete column.

2. The precast concrete column body includes a joint portion joined to a beam, The unadhered portion is provided at least in a part of the joint portion, the unbonded precast prestressed concrete column according to Claim 1.

3. The assembled reinforcement is covered by a covering material in the unadhered portion, the unbonded precast prestressed concrete column according to Claim 1 or Claim 2.

4. The covering material is an elastic body, the unbonded precast prestressed concrete column according to Claim 3.

5. The covering material is clay, vinyl tape, or butyl rubber, the unbonded precast prestressed concrete column according to Claim 3.

6. Further including lateral reinforcement embedded in the precast concrete column body, The lateral reinforcement is in contact with the covering material, the unbonded precast prestressed concrete column according to any one of Claims 3 to 5.

7. The tension member is provided inside the assembled reinforcement, the unbonded precast prestressed concrete column according to any one of Claims 1 to 6.

8. The assembled reinforcement is provided at the four corners of the precast concrete column body, the unbonded precast prestressed concrete column according to any one of Claims 1 to 7.

9. Precast concrete column bodies arranged in a plurality in the vertical direction and forming an unbonded precast prestressed concrete column, A tension member inserted through the concrete in an unbonded state, Including assembled reinforcement embedded in the concrete and extending to a recess provided from one end to the other end side of the precast concrete column body, The assembled reinforcement includes an unadhered portion that does not adhere to the concrete, a precast concrete column body.

10. The precast concrete column body according to claim 9, wherein the assembled reinforcing bars are covered with a covering material at the non-adhering part.

11. The precast concrete column body according to claim 10, wherein the covering material is an elastic body.

12. The precast concrete column body according to claim 10, wherein the covering material is clay, vinyl tape, or butyl rubber.

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