JP2659329B2 - Construction method of PC structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for constructing columns, beams, walls, floors and the like of a PC structure.

[0002]

2. Description of the Related Art In a conventional PC structure, a PC cable is laid in a cross section of a member and a prestress is applied in the form of internal stress. In that case, the sectional shape of the member is rectangular, I-shaped, T-shaped.
Shaped sections and the like were common. Also, the joints were integrated by cast-in-place concrete.

[0003]

When a PC structure is constructed of cast-in-place concrete, it requires support, formwork, scaffolding, etc., which requires a complicated process and a long construction period. Also, the conventional solid precast concrete members are heavy in weight, and there are great restrictions on handling such as transportation and lifting.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned problems, and to reduce the weight of a member while taking advantage of the features of the PC structure, and to provide a PC structure that can be easily joined to other members. It develops a construction method and provides it.

[0005]

The present invention solves the above problems.
The following technical measures were taken to solve the problem.
This is a method for constructing a PC structure. That is, the present inventionStep
Prestressing by retention or post tension
Is introducedConcave section with open topIn the longitudinal middle position
At least one diaphragm with an insertion hole
Prestressed concrete beams providedProduce the mounting position
After being placed in the concave section,Penetrates the insertion hole
Let mePC cable with out cable methodStretching arrangement
Then, tension the PC cable and join it to the mounting member.
This is a method for constructing a PC structure.

According to the present invention, a PC member having a concave cross section with an open upper surface for stretching an out cable is molded by a pre-tension or post-tension method using a primary cable. Inside, the connecting PC cable is divided into secondary and tertiary cables by the out-cable method, and the PC cable is tensioned and connected to orthogonal mounting members such as columns, beams, walls, etc. To construct.

[0007]

According to the present invention, a PC member having a concave cross section for stretching an out cable is manufactured in advance by a pre-tension or post-tension method, and is a lightweight intermediate member until it is transported to a building construction site and erected. The product can be easily handled, transported, lifted, erected, etc. as a PC member of the product, and a PC cable is wired within the concave cross section, and the cable is tension-joined to an orthogonal member such as a pillar by an out-cable system, and then the concave shape The section was filled with concrete. Therefore,
Even a member having a large final cross section and a large weight can be reduced in weight up to the erection stage, so that restrictions on transportation and lifting can be reduced.

The shape of the PC member may be such that it has a concave cross section over the entire length in the axial direction of the member, and only the ends are made solid, or a wall (diaphragm) provided with a PC cable insertion hole. May be provided at required positions in the longitudinal direction of the member. Any shape may be used as long as the cross section has a concave cross section where the out cable is stretched. According to the present invention, large-scale supports and brackets are not required as the members are reduced in weight, and the PC cable is wired in a concave cross section, so that the work is easy. In addition, PC cable insertion holes are provided near the bottom of a wall (diaphragm) provided at the mounting position of a small beam or the like, so that the PC cable becomes a bent-down wiring and the joining tension to the mounting member is reduced. Bending force by prestress can be used effectively.

When the PC member is joined to the mounting member, for example, when the beam is joined to the column, it may be individually joined to the orthogonal attaching member. When the PC members are continuous, a large number of members are sandwiched between the joining members. The PC members may be continuously joined. The PC member can be used as a structural member without filling the concave section, but after constructing the PC structure by the out-cable method, concrete is filled in the concave section, and the solid composite member is used. You can also.

In the PC structure according to the present invention, a large pre-stress can be introduced by applying the pre-stress stepwise without damaging the members due to overstress during the construction. Although there are merits, especially the load of 1,000 kg / m ²
It is very effective for heavy-loading structures such as warehouses and artificial terraces.

[0011]

1 and 2 show a construction PC according to an embodiment of the present invention.
It is a figure which shows the construction process of a structure. The construction method of the embodiment will be described with reference to the drawings. (A) The pillar 1 is constructed. (B) The girder 2 is erected. Girder 2 is precast PC
Since it is a beam and has a cross-sectional shape having a concave cross-section, it is lightweight. If a small bracket is attached to the column 1 to support the beam, the beam can be easily supported.
This bracket may be a notch provided in the pillar itself.

The sectional shape of the PC member such as the large beam 2 or the small beam 11 may be, for example, as shown in FIG. FIG. 3 shows a beam 2 having a U-shaped cross section. This U-shaped beam 2
Is obtained by forming a precast by a pretension method using the primary cable 15, and the secondary cable insertion hole 1
6. The diaphragm 3 having the tertiary cable insertion hole 17 may be formed in advance.

(C) The joint between the column 1 and the girder 2 is filled with joint mortar, and the girder 2 is provided with a secondary cable 4 and a tertiary cable 5 housed in a sheath. Then, the column 1 and the girder 2 are joined. When the girder 2 is continuous with the column 1 interposed therebetween, the secondary cable 4 can penetrate them and connect them simultaneously. The tertiary cable 5 is similarly arranged. After that, the small beam 11 and the precast slab 7 are erected.

The secondary cable 4 bears its own weight and work load such as the small beam 11 and the precast slab 7, and the diaphragm 3 is provided at a required position of the large beam 2 and the small beam 11, as shown in FIG. By providing the secondary cable insertion hole 16 in the vicinity of the bottom part, a bending up force due to tension can be applied, and a rational structure can be obtained. The tertiary cable 5 resists external loads such as an earthquake and a load.

(D) The secondary cable 4 is tensioned, the tertiary cable 5 is wired, and the precast slab 7 is installed. The girder 2 is continuously joined across the column 1. (E) Casting girder concrete 6 in place in the concave section. At this time, since the girder 2 itself becomes a formwork, no formwork or support is required.

FIG. 5 is a plan view of the PC structure in the steps up to here, and FIG. 6 is a view taken along the line AA of FIG. Pillar 1, 1
The girders 2 are erected between the… and the diaphragms 3 of the girders 2 and 2
A small beam 11 is erected at the position of
Is arranged. The joining of the small beam 11 to the large beam 2 is performed in the same manner as the joining of the column 1 of the large beam 2 as shown in FIG. (F) Tension the tertiary cable 5 and grout it. If necessary, top concrete 8 is cast.

(G) FIG. 2 (g) is a partial detailed view in which the girder 2 is joined to the column 1 , the secondary cable 4 and the tertiary cable 5 are arranged, and the precast slab 7 and the top concrete 8 are constructed. is there. Primary cable 1 that bears the weight of girder 2
5. Work load for construction and self-weight of small beams, precast slabs 7, top concrete 8, etc., secondary cable that bears tension for joining beams and columns, and external load that acts on the completed structural form Tertiary cables are rationally arranged, and a tough and lightweight structure can be constructed.

FIG. 4 exemplifies a PC member having a concave cross section formed by combining a plurality of beams 22 having an I- shaped cross section. The girder 22 is formed by pre-casting the primary cable 15 by a pretension method. A plurality of girder 22 are juxtaposed, and the joint concrete 23 and the diaphragm 3 are installed between the lower flanges of the girder 22 to arrange the out cable. It is made possible.

As described above, the PC member used in the present invention is:
Any shape may be used as long as it has a concave cross-section for stretching the out cable.

[0020]

According to the present invention, since the weight of the PC structure is reduced, it contributes to the reduction of the capacity of the transport vehicle and the lifting function and the reduction of the transport cost. In addition, the omission of the formwork and the shoring and the simplification of the bracket are possible, and the filling concrete does not require high-strength concrete. Further, the secondary cable can be easily stretched and can be bent up, so that the construction cost can be increased. And the number of steps can be reduced.

[Brief description of the drawings]

FIG. 1 is a process chart showing a method for constructing a PC structure according to an embodiment.

FIG. 2 is a process chart showing a method for constructing a PC structure according to an embodiment.

FIG. 3 is a sectional view of a beam according to the embodiment.

FIG. 4 is a sectional view of a beam according to the embodiment.

FIG. 5 is a plan view showing an arrangement of columns and beams in the embodiment.

FIG. 6 is a view as viewed in the direction of arrows AA in FIG. 5;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 pillar 2 girder 3 diaphragm 4 secondary cable 5 tertiary cable 6 girder concrete 7 precast slab 8 top concrete 11 girder 15 primary cable 16 secondary cable insertion hole 17 tertiary cable insertion hole 22 girder 23 joint concrete

Claims (1)

(57) [Claims] 1. Pre-tension or post-tension
Prestress is introduced by a method, at least one of which has an insertion hole at a middle position in the longitudinal direction with a concave cross section having an open upper surface.
Prestressed concrete with multiple diaphragms
After fabricating the beam and arranging it at the mounting position, the PC cable is stretched and arranged in the concave section in the out-cable manner through the insertion hole , and the PC cable is tensioned and joined to the mounting member. A method for constructing a PC structure, comprising constructing.