JPH0726660A - Pc small beam - Google Patents

Abstract

PURPOSE:To reduce material costs while required strength is being maintained and construction work is easily performed at low cost. CONSTITUTION:A PC small beam 10 has a plate 11 for joining a pair of large beams wherein the plate 11 is located at the end of a PC small beam body 12 of reinforced concrete so as to extend along the vertical surface thereof and the end of the plate is exposed to the outside from the and face of the body 12 arid the proximal end thereof is embedded in the body 12, and an underside bearing plate 15 which is disposed approximately along a horizontal plane while it is embedded in the body 12 together with the proximal end side of the plate 11 is welded to the lower end on the proximal end side of the plate 11. And deformed steel anchor bars 16, 16 or vertical plane bearing plate 19 or stud bolt 20 can be provided, or stirrup bars 22, 22 can be disposed around the plate 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a PC equipped with a plate for connecting to a girder as a structure of a joint part for joining with a girder.
It's about joists.

[0002]

2. Description of the Related Art As a floor structure of a building structure, a floor slab is used.
A flat slab structure in which columns are directly supported by columns with column capital without using beams, or a structural model in which beams are erected between columns to form the main structural frame and a floor is built between the beams. There is. Of these, the latter is called the O-beam type,
It is widely used in various building structures. In the case of adopting the girder type as a structural type, a girder may be installed between columns and a girder may be installed between the girders to form a frame structure. In this case, in the large beam type, the small beam is often made into a PC for reasons such as labor saving and shortening of a construction period. In addition, the connection between the girder and the PC girder is generally performed by connecting the girder to the PC girder as shown in FIG.
Rib plate 3 provided on the end surface of the PC beam main body 2 of the beam 1.
And the gusset plate 4 provided on the side surface of the girder 1A by bolting. Large beam 1 mentioned above
In the joint structure of A and the PC girder 1, the PC girder main body 2
The load applied to the PC girder main body 2 to the rib plate 3
Is transmitted to the girder 1A side through. In this case, if the fixing structure of the PC girder main body 2 and the rib plate 3 is weak, they are relatively displaced, so that there arises a problem that the strength of the girder 1A and the PC girder 1 are not properly joined. Therefore, here, it becomes necessary to strengthen the fixing structure of the rib plate 3 and the PC girder main body 2. Conventionally, P that has taken such measures
As the C beam, the one shown in FIGS. 6A to 6C is provided. In the PC beam 5 shown in this figure, the base end side of the PC beam main body 6 made of reinforced concrete is exposed to the outside from the end surface 7 of the PC beam main body 6 at the base end side.
The plate 8 for connecting to the girder is arranged in a state of being embedded inside the C girder main body 6, and two deformed steel bar anchor bars are provided, two on each of the upper and lower sides of the plate 8 for connecting the girder. Are welded together. In this case, the deformed steel bar anchor bars 9, 9 ... Are embedded in the PC girder main body 6 together with the base end portion of the plate-to-girder bonding plate 8, and are bent so that each pair of upper and lower parts gently opens. It has been processed.

[0003]

However, since the conventional PC beam 5 has the structure as described above, the required number of deformed steel bar anchor bars 9, 9 ...
Since a step of bending the deformed steel bar anchor bars 9, 9 ... Is required, there is a drawback that the cost of the entire PC beam becomes high.

The present invention has been made in view of the above circumstances, and provides a PC beam which can be obtained at a low cost while ensuring the required yield strength, and at the same time, can be processed easily. The purpose is to

[0005]

In order to achieve the above-mentioned object, the PC beam of the present invention is located at the end of the PC beam main body made of reinforced concrete so as to be along the vertical plane, and the tip side thereof is A PC beam having a plate for beam-to-beam connection that is exposed to the outside from the end face of the end portion and is embedded in the PC beam body at the base end side, and the base end side lower end portion of the connection plate is provided. Further, a lower surface bearing plate disposed along a substantially horizontal plane is welded in a state of being embedded in the PC beam main body together with the base end side.

According to the present invention, the joining plate is embedded in the PC girder main body at the upper end portion on one surface side and the lower end portion on the other surface side of the joining plate, respectively. In the state where the deformed steel bar anchor bar protruding and extending linearly in the extending direction of the PC beam main body is welded or embedded in the PC beam main body at the base end portion of the joining plate, A vertical bearing plate arranged along a vertical plane that is substantially orthogonal to the vertical plane is welded, or is embedded in the PC beam main body on both sides of the base end of the joining plate in a substantially horizontal direction. It is also possible to weld a stud bolt protruding to the end or to dispose a stirrup streak in a state of being embedded in the PC girder main body so as to rotate around the joining plate. .

[0007]

According to the structure of the PC girder of the present invention, the load applied to the PC girder main body is buried in the PC girder main body, and the lower surface bearing plate is welded to the lower end of the base end side. It is transmitted to the girder side through the girder joint plate. Further, in order to transmit the load to the girder side, in addition to the lower surface bearing plate, a deformed steel bar anchor bar, a vertical surface bearing plate, or a joining plate for girders welded with protruding stud bolts, or in addition to these, This is also performed by the girder joint plate arranged so that the stirrup stirrup wraps around it.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. First, FIG. 1 is a diagram showing a first embodiment of a PC beam according to the present invention. In FIG. 1, reference numeral 10 is a PC beam, and this PC beam 10 has a rib plate 11 (compared with a rib plate 11 at the end 13 of a PC beam main body 12 made of reinforced concrete as a structure of a joint part for joining with a beam. The plate for connecting the cross beam) is provided.

The PC girder main body 12 is composed of reinforcing bars arranged in a hardened concrete body having a substantially rectangular cross section and extending in one direction. The reinforcing bars for slab construction (not shown) are provided on the upper surface thereof.
Is provided in an exposed state.

The rib plate 11 is arranged at the end 13 of the PC beam main body 12 along a vertical plane passing through the center of the PC beam 10, and the end portion 13 is located at the tip 1a side.
Is exposed to the outside from the end face 13a of the
It is embedded and arranged in the beam main body 12. The rib plate 11 is a substantially rectangular metal steel plate and has an end surface 13a.
Connection holes 14, 14, ... For joining to the girder are formed in the portion exposed to the outside.

A lower surface bearing plate 15 is welded to the lower end of the rib plate 11 which is embedded in the PC beam main body 12 on the side of the base end 11b. The lower surface support plate 15 is a substantially rectangular metal steel plate made of the same material as that of the rib plate 11, and has a width dimension slightly protruding to both sides of the rib plate 11 and a size smaller than the embedded portion length of the rib plate 11. Rib plate 1 having a length dimension
It is arranged along a substantially horizontal plane in a state of being buried in the PC girder main body 12 together with the base end 11b side of No. 1.

In order to manufacture the PC beam 10, first, a rib plate 11 to which a lower surface support plate 15 is welded is prepared to form a formwork, and on the other hand, reinforcing bars are arranged inside the lower frame, and at the same time, the lower surface is formed. The rib plate 11 provided with the bearing plate 15 is supported at a prescribed position, the inside of the form is filled with concrete, and the concrete is solidified. The PC girder 10 configured as described above is fixed to the girder in a fixed position by connecting the gazette plate and the rib plate 11 formed on the girder with bolts and nuts, similarly to the one shown in FIG. Is installed in.

The load applied to the PC girders 10 installed between the girders is transmitted to the girder side through the connecting portion between the rib plate 11 and the gazette plate on the girder side. At this time, if the rib plate 11 and the PC girder main body 12 are fragilely fixed to each other, relative displacement occurs between them and the support of the PC girder 10 becomes uncertain. In FIG. 10, since the lower surface bearing plate 15 is welded to the rib plate 11, relative displacement between the rib plate 11 and the PC girder main body 12 is prevented. That is, although the rib plate 11 is arranged along the vertical plane, the lower surface bearing plate 15 is welded to the rib plate 11 along the horizontal plane, so that the rib plate 11 is smaller than the PC with respect to the vertical load. It functions to prevent relative movement within the beam body 12 within a vertical plane. Thus, PC
In the beam 10, the relative movement of the rib plate 11 and the PC beam main body 12 is prevented, and the state in which the PC beam 10 is reliably fixed in a fixed position is maintained.

Therefore, in this PC girder 10, by providing the lower surface bearing plate 15, the required yield strength is secured, while the conventional PC girder 5 shown in FIG.
Multiple bent bar steel anchor bars 9 compared to
Since it is unnecessary, the entire PC beam 10 can be provided at low cost. In addition, the lower pressure bearing plate 15
Since it can be formed from the metal steel plate of the same material as the rib plate 11, the material can be easily procured, and the configuration is simple, so that the entire PC beam 10 can be easily manufactured.

Next, a second embodiment shown in FIG. 2 will be described. In FIG. 2, the same components as those of the first embodiment shown in FIG. 1 are designated by the same reference numerals, and the description thereof will be omitted (hereinafter, also in the third, fourth, and fifth embodiments, The same shall apply). The difference between this embodiment and the first embodiment is that, as shown in FIG. 2, in addition to the structure of the first embodiment, the deformed steel bar anchor bars 16, 16 are welded to the rib plate 11. That is, the upper end portion of the rib plate 11 on the one surface 17 side and the lower end portion of the other surface 18 side protrude from the rib plate 11 while being embedded in the PC girder main body 12, respectively. 12 deformed steel bar anchor bars 16 and 16 extending in the extending direction are welded.

The deformed steel bar anchor bars 16 and 16 are obtained by cutting the deformed steel bar anchor bars, which are linearly manufactured at the factory, into predetermined dimensions, and the end portions of the deformed steel bar anchor bars 16 are ribbed without any particular bending work. Is welded to.

In the PC beam 10A of the second embodiment, since the deformed steel bar anchor bars 16 and 16 are welded to the base end side of the rib plate 11 while being embedded in the PC beam main body 12, the rib plate 11A is welded. The fixing strength between 11 and the PC girder main body 12 can be further strengthened. That is, in the configuration of the PC beam 10A, in addition to the action of the lower surface bearing plate 15, the deformed steel bar anchor bars 16, 1
By providing 6, the relative displacement of the rib plate 11 in the PC beam main body 12 in the vertical plane is reliably suppressed. In addition, the rib plate 11 is not only fixed at the end of the PC beam main body 12, but also the deformed steel bar anchor bars 16 and 16 extend inwardly of the PC beam main body 12 and therefore, The P with the PC beam main body 12
The relative displacement of the C beam main body 12 in the longitudinal direction is suppressed,
The mutual fixation becomes extremely strong. Therefore,
According to the PC girder 10A of the second embodiment, in addition to the effect of the first embodiment, the rib plate 11 and the PC girder main body 1 are provided.
The fixing strength with No. 2 can be further improved. In addition, this PC girder 10A requires a smaller number of deformed steel bar anchor bars than the conventional PC girder 5 shown in FIG. 5 and does not require bending work. There is an effect that the entire 10A can be provided at low cost.

Next, a third embodiment shown in FIG. 3 will be described. The PC beam 10B shown in this figure is different from that of the first embodiment in that a vertical bearing plate 19 is welded to the end face (rear end face) of the base end portion 11b of the rib plate 11.

The vertical bearing plate 19 is the rib plate 1
In a state of being embedded in the PC beam main body 12 together with the base end side 11b of 1, the vertical plane passing through the central part of the PC beam main body 12 (the vertical plane along which the rib plate 11 is placed) is perpendicular to the vertical plane. It is arranged and welded to the rib plate 11. The vertical pressure bearing plate 19 is a substantially rectangular metal steel plate made of the same material as the rib plate 11,
1 has a width dimension slightly overhanging on both sides and a length dimension substantially the same as the length of the embedded portion of the rib plate 11.

In this embodiment, as compared with the structure of the first embodiment, the vertical bearing plate 19 is provided, so that the same operation as that of the first embodiment can be obtained, while the rib plate 11 is provided.
When a force that causes relative displacement in the longitudinal direction of the PC beam main body 12 is applied between the PC beam main body 12 and the PC beam main body 12, the vertical movement support plate 19 reliably prevents the relative movement.

Therefore, according to this embodiment, in addition to the effect described in the first embodiment, in particular, the rib plate 11 and the PC are
The relative movement of the PC beam main body 12 in the length direction between the beam main body 12 and the beam main body 12 can be reliably prevented, and the rib plate 11 and P
The fixing strength between the C beam main body 12 can be further improved.

Next, a fourth embodiment shown in FIG. 4 will be described. The PC beam 11C shown in this figure is different from that of the first embodiment in that stud bolts 20 protruding in a substantially horizontal direction are welded to both surfaces of the base end portion 11b of the rib plate 11.

The stud bolt 20 is a joining member made of the same material as the rib plate and having a head portion 21 and a rod portion 22.

In the PC beam 10C of the fourth embodiment, the stud bolt 20 is different from the structure of the first embodiment.
Since the same effect as that of the first embodiment is obtained, the relative movement of the rib plate 11 in the PC beam main body 12 in the vertical plane is suppressed, and the rib plate 11 and the PC beam main body 12 are provided. Relative movement in the length direction of the PC girder main body 12 between and is reliably prevented.

Therefore, according to this embodiment, in addition to the effects described in the first embodiment, the relative movement of the rib plate 11 in the PC beam main body 12 in the vertical plane and the rib plate 11 and the PC beam are performed. Rib plate 11 with main body 12
It is possible to reliably prevent relative movement in the length direction.

Next, a fifth embodiment shown in FIG. 5 will be described. The PC girder 10D shown in this figure is an embodiment in which the rib plate 11 and the lower surface bearing plate 15 are positioned inside the stirrup streaks 22, 22 arranged in the PC girder main body 12. That is, the main bars 21 and 21 are arranged in the PC beam main body 12, and the stirrup bars 22 and 22 are arranged to the main bars 21 and 21. Then, the rib plate 11 and the lower surface bearing plate 15 are arranged so as to be positioned substantially in the center of the stirrup streaks 22, 22.

In the PC girder 10D of the fifth embodiment, the rib plate 11 is different from that of the first embodiment.
And the stirrup streak 2 around the lower pressure bearing plate 15
Since 2, 22 are arranged, this stirrup muscle 22,
Reference numeral 22 denotes the rib plate 11 and the lower pressure bearing plate 15.
The surrounding concrete is restrained, and the rib plate 11 and the lower surface bearing plate 15 are more firmly held in the PC beam main body 12.

In each of the above embodiments, the rib plate 11 is provided with the lower surface bearing plate 15, the deformed steel bar anchor bars 16, 16, the vertical bearing plate 19, and the stud bolt 20. The present invention is not limited to these configurations, and for example, a member that reinforces the fixing of various rib plates 11 may be provided if necessary. In addition, in the embodiment of FIG. 5, the rib plate 11 and the lower surface bearing plate 15 are connected to the stirrup streak 2
It is arranged to be placed inside 2, 22.
In another embodiment shown in FIG. 5, stirrup streaks 22 and 22 may be arranged around each rib plate 11 to strengthen the fixation of the rib plate 11 to the PC beam main body 12. can do.

[0029]

According to the PC beam of the present invention, the following effects can be obtained. According to the PC girder of claim 1, a lower surface bearing plate is welded to the lower end portion of the plate for joining the girder on the base end side while being embedded in the PC girder body together with the base end side. Therefore, the lower pressure bearing plate can provide the necessary fixing strength between the plate for connecting girders and the PC girder main body, and since the structure is simple, the PC girders can be provided at low cost.

According to the PC girders of claims 2 to 5, any one of the deformed steel bar anchor bar, the vertical bearing plate, and the stud bolt is added to the beam-to-girder connection plate, and further, In addition to the above-mentioned effects, the PC is provided with stirrup streaks around the beam-to-beam connection plate.
The fixing strength between the beam main body and the beam-to-beam connection plate can be further increased.

[Brief description of drawings]

FIG. 1 is a diagram showing a first embodiment of a PC beam according to the present invention, in which (a) is a front view showing a schematic configuration of the PC beam;
(B) is the same top view, (c) is the same side view.

FIG. 2 is a diagram showing a second embodiment of the PC beam of the present invention, (a) is a front view showing a schematic configuration of the PC beam,
(B) is the same top view, (c) is the same side view.

FIG. 3 is a diagram showing a third embodiment of the PC beam of the present invention, (a) is a front view showing a schematic configuration of the PC beam,
(B) is the same top view, (c) is the same side view.

FIG. 4 is a diagram showing a fourth embodiment of the PC beam of the present invention, in which (a) is a front view showing a schematic configuration of the PC beam;
(B) is the same top view, (c) is the same side view.

FIG. 5 is a view showing a fifth embodiment of the PC beam of the present invention, in which (a) is a front view showing a schematic configuration of the PC beam;
(B) is the same top view, (c) is the same side view.

FIG. 6 is a diagram showing a conventional PC beam, in which (a) is P
The front view which shows the schematic structure of C small beam, (b) is the same plan view,
(C) is the same side view.

FIG. 7 is a vertical cross-sectional view of a joint structure of a girder and a PC girder.

[Explanation of symbols]

 10 PC beam 11 Rib plate (joint plate) 12 PC beam main body 15 Lower surface bearing plate 16 Deformed steel bar anchor bar 19 Vertical surface bearing plate 20 Stud bolt 22 Stirrup bar

Claims (5)

[Claims] 1. The PC beam girder main body made of reinforced concrete is positioned along the vertical plane so that its tip end side is exposed to the outside from the end face of the end, and the base end side is inside the PC girder main body. PC with a beam-to-beam connection plate buried in
A lower beam supporting plate, which is a beam and is arranged along a substantially horizontal plane at a lower end portion on the base end side of the joining plate and is embedded in the PC beam body together with the base end side. PC girder characterized by being welded. 2. The PC girder according to claim 1, wherein an upper end portion on one surface side and a lower end portion on the other surface side of the joining plate respectively extend from the joining plate to the inside of the PC strut main body. A PC beam having a deformed steel bar anchor bar that protrudes in a state of being embedded in and is linearly extended in a direction in which the PC beam body extends. 3. The PC girder according to claim 1, wherein the PC girder is disposed along a vertical plane substantially orthogonal to the vertical plane in a state of being embedded in the PC girder main body at a base end portion of the joining plate. PC beam to which the vertical bearing plate is welded. 4. The PC girder according to claim 1, wherein stud bolts protruding in a substantially horizontal direction are welded to both sides of a base end portion of the joining plate while being embedded in the PC girder body. PC girder characterized by having. 5. P according to any one of claims 1 to 4.
In the C girder, a stirrup streak is arranged in a state of being embedded in the PC girder main body so as to wind around the bonding plate, and the PC girder.