JPH0635734B2 - PC flat slab construction method for chieve structure - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a PC flat slab construction method for a tube structure building, and more particularly, to a tube structure building capable of eliminating a beam in an interior space. The present invention relates to a PC flat slab construction method.

[Conventional technology]

In high-rise buildings and the like, a so-called tube structure is used in which the outer peripheral surface of the building is used as a structural body to treat it as a cylindrical shell and resist a horizontal load. In the tube structure, columns are arranged on the outer peripheral wall at short intervals, beams are passed between the columns to form a truss structure, and the outer wall surface is used for the structure. There is a double tube structure that employs the same structure as the outer peripheral wall, but in both cases, the interior can be made pillarless, which increases the degree of freedom in the room.

However, in terms of habitability, a suitable slab span dimension is 7 to 8 m, and in this span dimension, a beam to support the slab is indispensable. Therefore, the beam limits the free floor plan of the living space, and However, the advantages of the tube structure were not fully utilized. FIG. 5 and FIG. 6 show the arrangement of beam G in the conventional double-tube structure and single-tube structure building, respectively.

Moreover, in order to increase the support strength of the slab, a PC is used as a prestressed concrete (hereinafter referred to as "PC") structure.
Although strands are put in, conventionally, since both ends of the PC strand were fixed to the slab ends, the PC strand has fixed ends so as not to destroy concrete at both ends in order to firmly fix the both ends to the slab. Also, it was necessary to lower the tension end by about 100 mm from the upper surface of the slab and embed it. As shown in FIG. 4, the thickness T of the slab 2 is temporarily assumed.
200 mm, fixed end and tension end 8 of PC strand 8
The implantation depth d ₃ from the slab upper surface 2b of a and 8b is set to 1
00 mm, the concrete cover thickness d ₂ from the slab lower surface 2a of the PC strand 8 in the central part of the slab is 40 to
If it is 50 mm, the rise r ₁ of the PC strand 8 is 50.
Approximately 60 mm, and sufficient lifting force cannot be obtained. For this reason, small diameter strands can be placed inside the slab (outside the pillar) from 600 to
It is necessary to wire closely with a pitch of 1500 mm, and P
Even if the C strand was wired, a beam was required.

[Problems to be solved by the invention]

The present invention has been made in view of the above conventional problems and was devised to improve the problems. An object of the present invention is to adopt a PC flat slab for a tube structure and eliminate the beam in the indoor space. It is to provide a method for constructing a PC flat slab for a tube structure building that enables the above.

[Means for solving problems]

In order to achieve the above object, the technical means adopted by the present application are:
In a method of constructing a PC flat slab on a tube structure building, a PC strand for introducing post tension is formed into a tube structure, and the flat strand slab is sandwiched and wired between two columns facing each other. In the flat slab, a certain concrete cover thickness is placed close to the bottom surface of the flat slab, and in the vicinity of both ends of the flat slab, a certain concrete cover thickness is placed close to the top surface of the flat slab. The two ends of the strand are pierced substantially horizontally in the two columns from the vicinity of the upper surface of the flat slab, and one end of the fixing end of the strand is opposite to the end of the column facing the penetrating part of the strand. It is fixed to the end, and the other end of the strand at the side end facing the penetrating part of the strand of the other column is tensioned to provide post tension. It is characterized in that so as to introduce emissions.

[Action]

In the present invention, the PC strand for introducing the post tension, which has been conventionally wired in the slab, is wired between each two columns facing each other across the flat slab, and the fixation of the PC strand is fixed to the strand of the column. Since it is the side end facing the penetration part, even if the embedding depth of the PC strand near both ends of the slab is about the normal concrete cover thickness, a sufficient concrete cover thickness can be obtained on the column side,
The fixing of both ends of the PC strand is surely performed. Therefore, unlike the conventional case, it is not necessary to lower the fixed end and the tension end from the upper surface of the slab by a predetermined dimension in order to surely fix both end portions of the PC strand to the slab, and the rise of the PC strand is reduced to the thickness of the slab. On the other hand, it can be used as much as possible and the lifting force of the slab is greatly improved.

〔Example〕

 Hereinafter, the present invention will be described in detail based on embodiments of the drawings.

FIG. 1 is a side sectional view of a PC flat slab to which the present invention is applied, and FIG. 2 is the same as above in a double-tube structure building.
It is a top view which shows the strand wiring of a C flat slab. The double-tube structure 1 is constructed by three-dimensionally assembling an outer tube 1a and an inner tube 1b composed of columns 3 and girders 9 arranged in a predetermined span with slabs 2 of each layer. A balcony 5 and a corridor 6 of each floor are provided outside the outer tube 1a and inside the inner tube 1b.
Overhangs, and a void space 7 is formed inside the inner tube 1b.

The slab 2 is a PC flat slab constructed by the method according to the present invention, and the introduction of the tension of the slab 2 is performed by a post-tension method using an unbonded PC strand (hereinafter referred to as “strand”) 8 for introducing the post-tension. . The strands 8 form an outer tube 1a and an inner tube 1b, and are wired between two columns 3'and 3'opposed to each other with the slab 2 sandwiched therebetween, and the strands 8 are arranged in the transverse direction of the slab 2 as shown in FIG. In the central portion, the normally required concrete cover thickness d ₂ is arranged to approach the lower surface 2a of the slab 2, and in the vicinity of both ends in the transverse direction of the slab 2, the normally required concrete cover thickness d is the same as in the central portion. ₁ is placed close to the upper surface 2b of the slab 2 to form an upward concave shape in the slab 2 as a whole. Both ends of the strand penetrate the column bases 3a of the two columns 3'and 3'in the vicinity of the upper surface 2b of the slab in a substantially horizontal direction to form the penetration portions of the strands 8 of the two columns 3'and 3 '. Draws out on opposite sides. The above-mentioned wiring is carried out by supporting a normal reinforcing bar on the formwork 10 before placing the concrete of the slab 2. Then, after concrete is poured and cured, the fixed end 8a of the strand 8 is fixed to the pillar 3'on one side.
Is fixed to the side of the strand 8 facing the penetrating part, and the tensioning device 11 is used at the other end of the tensioning end 8b to introduce a post tension to face the penetrating part of the strand 8 of the column 3'on the other side. Fix on the side.

FIG. 3 shows an example of the tensioning device,
The tension device 11 mounts a known jack 11a on a carriage 11c equipped with a spherical omnidirectional traveling caster 11b, and is supported by a level adjusting nut 11d so that its height can be adjusted. Since the balcony 5 and the corridor 6 are already completed when the strand 8 is tensioned, as shown in FIG. 2, the tensioning device 8 is sequentially tensioned while moving the tensioning device 11 through the balcony 5 or the corridor 6. You can go. At this time, the level adjusting nut 11 is adjusted so that the height of the jack 11a becomes equal to the height of the strand 8.
If it is adjusted by d, then the tension end 8b of the strand 8 and the center hole of the jack 11a can be easily aligned with each other only by the positioning by the carriage 11c.

Here, the thickness T of the slab 2 is 200 mm, the concrete cover thickness d ₂ from the slab lower surface 2a of the strand 8 in the central portion of the slab ₂ is 35 mm, and the slab upper surface 2b of the strand 8 near both ends of the slab 2 is If the concrete cover thickness d ₁ is 45 mm, the rise of the strand 2 r
₂ is 120 mm, and the rise r ₁ (50 to 60) of the conventional method of fixing both ends of the strand to the both ends of the slab is used.
mm), the rise r ₂ is approximately doubled, and the lifting force of the strand is doubled. Therefore, even if the slab thickness is the same, a much higher bearing strength can be obtained compared to the conventional flat slab, and even if the span is 7 to 8 m, it is possible to omit the beam, and multiple slabs can be used. It is possible to use a wire having a diameter larger than that of the conventional strand to be wired.

The method according to the present invention can also be applied to a building having a single tube structure of the type shown in FIG.

〔The invention's effect〕

As described above, the present invention relates to a method of constructing a PC flat slab in a tube structure building, in which a PC strand for introducing post tension is formed into a tube structure, and two columns each facing the flat slab are provided. Wiring between the flat slab and the center of the flat slab with a specified concrete cover thickness close to the bottom of the flat slab, and near both ends of the flat slab with a specified concrete cover thickness and the top of the flat slab. To form a concave shape in the flat slab as a whole, and both ends of the strand are pierced substantially horizontally in the two columns from the proximity of the upper surface of the flat slab, and one end of the fixing end of the strand is The other end of the strand is fixed to the side end opposite to the penetration part of the strand, and the other end of the side end opposite the penetration part of the strand Tense it is so arranged to introduce the post Ten Chillon, even slab thickness are the same much higher supporting strength is obtained than a conventional PC slab, 7-8 m
It is possible to omit the beam even if the span is large. As a result, the effective space in the room is increased, the restrictions on the floor plan are reduced, and the habitability can be improved, and a building that takes advantage of both the tube structure and the flat slab structure can be obtained.

[Brief description of drawings]

The drawings show an embodiment of the present invention. Fig. 1 is a side sectional view of a PC flat slab to which the present invention is applied, and Fig. 2 is a P flat slab of the same in a double-tube structure building.
FIG. 3 is a plan view showing a C strand wiring, FIG. 3 is a side view showing an example of a PC strand tensioning device, and FIG. 4 is a conventional PC.
FIG. 5 is a side view showing the PC strand wiring of the slab, and FIGS. 5 and 6 are plan views showing the arrangement of beam beams in the conventional double-tube structure and single-tube structure building, respectively. 1 ... Tube structure building, 2 ... PC flat slab, 3 ... Column, 3 '... Opposite two columns, 8 ... PC strand, 8a ... Fixed end, 8b ... Tension end, 11 ... Tension Equipment, d ₁ , d ₂ ... Concrete cover thickness.

Claims (2)

[Claims] 1. A method for constructing a PC flat slab on a tubular structure, comprising a post tension PC.
A strand is formed into a tube structure, and a flat slab is sandwiched between two columns that are opposed to each other. At the center of the flat slab, a predetermined concrete cover thickness is arranged to be close to the bottom surface of the flat slab. Near the both ends of the flat slab, a certain concrete cover thickness is arranged to be close to the upper surface of the flat slab to form a concave shape in the flat slab as a whole, and two ends of the strand are respectively provided near the upper surface of the flat slab. Through the column in a substantially horizontal direction, one end of the fixing end of the strand is fixed to the end of the column facing the penetrating portion of the strand, and the other column of the column facing the penetrating portion of the strand. A method for constructing a PC flat slab for a tube-structure building, characterized in that the other end of the strand at the end is tensioned to introduce a post tension. 2. The introduction of the post tension is carried out while moving on an existing slab by a tensioning device having a tension jack mounted on a carriage equipped with an omnidirectional traveling caster so that the height of the tension jack can be adjusted. A method of constructing a PC flat slab for a tube-structured building according to item 1 above.