JP3275188B2 - Frame structure of large span roof and frame construction method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a large span roof frame structure suitable for constructing a large span roof covering a large space and a method of constructing a large span roof.

[0002]

2. Description of the Related Art As is well known, so-called dome roofs having a hemispherical curved surface and large-span roofs having a flat roof are provided as buildings providing a large space therein, such as stadiums and multipurpose halls. There are buildings.

Hitherto, in such a building, FIG.
As shown in FIG. 7, the boundary condition at the legs of the beam 11 is a pin bearing 12 at both ends, and a frame structure as a low-rise arch having a gentle curved surface, and a beam 13 as shown in FIG.
A frame structure was adopted in which a simple beam having one end as a pin support 14 and the other end as a roller support 15 was used as a boundary condition for the legs.

[0004]

However, each of the above frame structures has the following problems. That is, in the case of the above-described arch frame, it is necessary to treat the thrust force generated by the weight of the beam 11 by the lower structure (not shown), and the lower structure can process the thrust force. It had to be a strength design, which was uneconomical in construction.

In the case of a simple beam as described above, processing of the thrust force by the above-mentioned lower structure does not matter, but large bending occurs at the center of the beam 13. Therefore, in order to suppress such bending, the beam must be made large, and the construction must be uneconomical as in the case of the above-mentioned arch frame.

The present invention has been made in view of the above-mentioned problems, and does not require the thrust force treatment by the lower structure, and can suppress the deformation of the beam without increasing the beam width. Another object of the present invention is to provide a large span roof frame structure capable of suppressing construction costs. Another object of the present invention is to provide a method for constructing a large-span roof frame that can efficiently construct a large-span roof at a reduced construction cost.

[0007]

A large span roof frame structure according to claim 1 of the present invention is a large span roof frame structure for covering a large space, wherein the roof frame body is composed of beams extending radially . concentrically from the center of the roof Frame body to the lower surface
A connecting beam is provided to connect the beams,
A plurality of support rods facing down to the connecting beam and the roof frame body
The support rod is provided with a tension member attached to the support rod so as to surround the center, and a prestress is introduced into the tension member.

According to a second aspect of the present invention, there is provided a method of constructing a large span roof frame according to the first aspect of the present invention, wherein the roof frame body is divided concentrically from the center thereof. The supporting rods are suspended from these divided bodies, the inner divided bodies are supported at the construction position, and a tension member is attached to the supporting rods of the divided bodies. A prestress is introduced, and thereafter, an outer divided body is arranged on the outer peripheral portion of the inner divided body and joined thereto, and a tension member is attached to a support rod of the outer divided body to introduce the prestress. By repeating this process from the inside to the outside, a large span roof is constructed.

[0009]

According to the first aspect of the present invention, a beam extending radially
On the lower surface of the roof frame body
Connecting beams that are concentrically arranged to connect the beams
And a plurality of support rods are downwardly
Since the prestress is introduced into the tension members attached to the support rods , projecting downwardly from the root frame main body, a moment of upward bending back is generated at the center of the roof frame main body.

According to the second aspect of the present invention, a tension member is attached to the support rod of the inner divided body supported at the construction position so as to surround the center portion, and after introducing a prestress into the tension member, The outer divided body is arranged on the outer peripheral portion of the divided body and joined, and a tension member is attached to a support rod of the joined outer divided body to introduce a prestress, and the process from the inside to the outside is performed. By repeating the construction of a large span roof, it is possible to make a moment of upward bending back at the center of the assembled roof frame main body, and join the outer split body to the inner split body After that, the construction of the roof is promoted by supporting only the outer divided body.

[0011]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. FIG. 1 shows a first embodiment in which the frame structure of a large span roof according to the present invention is applied to a building structure having a flat large span roof. In the figure, reference numeral 1 denotes a building having a large span roof. FIG. 1 (a)
As shown in (b) and (b), the building 1 has a schematic configuration in which a roof 2 that is substantially horizontal in a side view and circular in a plan view is supported by a pillar 3 that is a lower structure at an outer peripheral portion of a lower surface thereof. I have.

The roof 2 is composed of beams (roof frame body) 4 extending radially in all directions from the center of the roof 2 and connecting beams connecting the beams 4 arranged concentrically from the center of the roof 2. 5a, 5b, 5c, these beams 4,...
a, 5b, 5c, and a roofing material (not shown). The connecting beams 5a, 5 of the beams 4 ...
The struts (supporting rods) 6a..., 6b.
Are fixed downward. That is, these struts are annularly arranged so as to surround the center of the roof 2.

These struts 6a ..., 6b ..., 6c ...
Struts 6a ..., 6 adjacent in the circumferential direction of the roof 2
b ..., 6c ... tension ring wire (hereinafter, referred to as
Called "wire." ) (Tensile members) 7a, 7b, 7c are wound around the center of the roof 2, and prestress is introduced into these wires 7a, 7b, 7c.

Next, a method of constructing the frame of the roof 2 in the building 1 will be described with reference to schematic process diagrams shown in FIGS. 2 (a) to 2 (c) and moment diagrams shown in FIGS. 3 (a) to 3 (c). explain. First, as shown in FIG. 2A, a unit roof 2a (divided body) which is a central portion of the roof 2 is constructed.
That is, in this step, the unit beam 4 obtained by dividing the beam 4 is used.
a are connected by connecting beams 5a (see FIG. 1A), and the unit roof 2 is attached to the lower ends of the struts 6a fixed to the unit beams 4a through wires 7a.
are supported, and the lower ends of the struts 6a are supported by a support 8a having roller supports, and the support 8a is jacked up so that the unit roof 2a is positioned at a predetermined height. Then, prestress is introduced into the wire 7a. The moment of the roof 2 in this process is shown in FIG.
As shown in (a), on the unit beam 4a and on the strut 6
occurs outside of a.

Next, as shown in FIG. 2B, a unit roof 2b (divided body) is joined to the outside of the unit roof 2a.
That is, in this step, the unit beam 4 obtained by dividing the beam 4 is used.
b is connected by a connecting beam 5b to form a unit roof 2b,
In the same manner as the unit roof 2a, the lower ends of the struts 6b are supported by a support 8b using roller support, and the support 8b is jacked up so that the unit roof 2b is positioned at a predetermined height. The unit beam 4a of the unit roof 2a
And the unit beam of the unit roof 2b and 4b are joined. further,
A wire 7b is wound around the lower end of the struts 6b fixed to the unit beam 4b, and prestress is introduced into the wire 7b. Then, the support (not shown) supporting the unit roof 2a is removed. As shown in FIG. 3B, the moment of the roof 2 in this step is generated on the unit beams 4a and 4b and outside the struts 6b in addition to the moment generated in the step.

Further, as shown in FIG. 2C, a unit roof 2c (divided body) is joined to the outside of the unit roof 2b. In this step, similarly to the above-mentioned step of the unit roof 2b, the unit beams 4c obtained by dividing the beams 4 are connected by connecting beams 5c to form the unit roof 2c, and the lower ends of the struts 6a are used as roller bearings. The support 8c is jacked up so that the unit roof 2c is supported at the predetermined height by the support 8c. Then, the unit beam 4b of the unit roof 2b and the unit beam 4c of the unit roof 2c are joined. Further, a wire 7b is wound around the lower end of the struts 6b fixed to the unit beam 4b, and prestress is introduced into the wire 7b. Then, the support (not shown) at the leg of the unit beam 4b of the unit roof 2b is removed. As shown in FIG. 3C, the moment on the roof 2 at this time is, in addition to the moment generated in the step of FIG. 2B, on the unit beams 4a, 4b, 4c and on the struts 6c.
Occurs outside of

Then, the connecting beams 5a,..., 5b,... 5c, which are roller-joined, are fixed between the beams 4, and the construction of the frame of the roof 2 is completed.

In the frame structure of the roof 2 of the building structure 1 having the above-mentioned structure, struts 6a, 6b, 6c, 6c are suspended from the lower surface of the beams 4, so as to surround the center of the roof 2.
Wires 7a, 7b ... are wound around these struts,
Since the prestress is introduced into these wires 7a, 7b,..., A moment of upward bending back is generated at the center of the roof 2 as described above.

As described above, according to the above embodiment, a plurality of struts 6a, 6b, 6c, and 6c are arranged annularly on the lower surface of the beam 4 so as to surround the center of the roof 2. Since prestress is introduced into the wires 7a, 7b attached to these struts 6a, 6b, 6c, to generate an upward bending back moment in the center of the roof 2, the roof book Bending at the central part of No. 2 can be suppressed. Therefore, it is not necessary to treat the thrust force by the lower structure such as the conventional frame structure or to increase the beam width, so that a structure having a large span roof can be constructed while suppressing the construction cost.

In addition, a wire is wound around a strut suspended from a unit beam of the unit roof, a prestress is introduced into the wire, and an outer unit roof is joined to an outer peripheral portion of the inner unit roof. The roof 2 is constructed by repeating the process of winding a wire around the strut hanging on the unit beam of the outer unit roof and introducing prestress, so that the center of the assembled roof 2 is It can be in a state where a moment of bending back upward has occurred, and after joining the outer unit roof to the inner unit roof,
The construction of the roof 2 can be advanced in a state where the support of the inner unit roof is removed and only the outer unit roof is supported.
Therefore, the support of the inner unit roof can be diverted to the support of the outer unit roof to be newly joined, and the construction period can be shortened and the construction cost can be reduced.

FIG. 4 shows a second embodiment of the frame structure of a large span roof according to the present invention. As in the first embodiment, the frame structure in this embodiment has beams 4 extending radially from the center of the roof 2 in all directions and beams 4 concentrically arranged from the center of the roof 2 to connect the beams 4 to each other. Connecting beams 5a, 5b, 5c, and these beams 4, ..., connecting beams 5a, 5
b, installed roofing material placed on 5c (not shown)
It is composed of

Struts 6a, 6b, 6c are fixed to the lower surfaces of the joints of the beams 4 and the connecting beams 5a, 5b, 5c at predetermined intervals in the longitudinal direction of the beams 4 ... Have been. And beams 4 which are orthogonal to each other in plan view
It is wound around a strut fixed to a square so as to be substantially square. In this case, the operation and effect similar to those of the first embodiment can be obtained, although the degree of introduction of the prestress into the wires 7 is different.

FIGS. 5A and 5B show a third embodiment of the frame structure of a large span roof according to the present invention. In the figure, the same parts as those in the first embodiment are denoted by the same reference numerals, and description thereof will be omitted.

As shown in FIG. 5B, in this embodiment, the building 1 has a low-rise arch roof 9 having a circular shape in plan view.
Has a schematic configuration supported by the lower structure 10 at the outer peripheral portion of the lower surface thereof.

As shown in FIG. 5B, the roof 9 has beams 4 extending radially from the center thereof in all directions.
Connecting beams 5a, 5b, which are arranged concentrically from the center of the roof 9 and connect the beams 4, and roofing materials (not shown) installed on these beams 4, ..., connecting beams 5a, 5b, etc. It is composed of The connecting beams 5a, 5c of the beams 4 ...
Struts 6a..., 6b. These struts 6a
Wires 7a and 7b are wound around lower ends of the wires 7a and 7b, respectively. Prestress is introduced into the wires 7a and 7b.

As in the first embodiment, the frame structure of the roof 9 of the third embodiment can be constructed for each of the unit roofs obtained by dividing the roof 9 concentrically. In this case, in order to avoid the generation of stress in the circumferential direction of the roof 2 due to the shell effect, the connection between the beam 4 and the connecting beams 5a, 5b is set by roller bonding, and the outermost one of the wires 7 is used. Fix after introducing prestress.

According to the frame structure of the roof 9, the same operation and effect as those of the first and second embodiments can be obtained, and a shell effect can be expected. Therefore, the number of the tension ring wires is equal to that of the first and second embodiments. The number can be reduced as compared with the flat roof of the second embodiment.

In each of the above embodiments, the present invention is applied to a building structure having a large-span roof having a circular shape in plan view.
Needless to say, the present invention can be applied to a structure having a large span roof having a polygonal roof such as a square or a hexagon in plan view.

[0029]

According to the large span roof frame structure and the large span roof frame construction method of the present invention, the following effects can be obtained. According to Frame structure of large span roof according to claim 1, concentrically from the center of the roof Frame body to the lower surface of the roof rack構本body made of beams extending shape radiate
A connecting beam is provided to connect the beams,
A plurality of support rods are directed downward on the bridge beam and the roof frame body is
Projecting downward, it is fixed in an annular shape , and a tension member is attached to these supporting rods so as to surround the center portion, and a prestress is introduced into the tension member, so that a moment of upward bending back to the center portion of the roof frame body is generated. Since this is caused, bending at the center of the roof frame main body can be suppressed.
Therefore, it is not necessary to treat the thrust force by the lower structure such as the conventional frame structure or to increase the beam width, so that a structure having a large span roof can be constructed while suppressing the construction cost. Also, concentric with the roof frame body
Bending moment can be given to the connecting beam
As a result, the roof frame body is
To give an almost uniform return moment.
The roof frame body to be a smooth arcuate curved surface
it can.

According to the method for constructing a large span roof frame according to the second aspect, a tension member is attached to the support rod of the inner divided body supported at the construction position, and after the prestress is introduced into the tension member, A step of arranging an outer divided body on the outer peripheral portion of the inner divided body and joining them, and winding a tension member around a supporting rod of the joined outer divided body to introduce a prestress is performed from the inside. Since the construction of the roof frame is performed by repeatedly performing outward, a moment of upward bending back occurs at the center of the assembled roof main body, and after joining the outer divided body to the inner divided body The construction of the roof frame can be advanced with the support of the inner divided body removed and the outer divided body supported. Therefore, the support of the inner divided body can be diverted to the support of the outer divided body to be newly joined, and the construction period can be shortened and the construction cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a view showing a first embodiment of a large span roof frame structure according to the present invention, wherein (a) is a schematic plan view and (b) is a schematic front sectional view.

FIGS. 2A and 2B are schematic process diagrams showing an example of a procedure for constructing a frame structure of a large span roof according to the embodiment, wherein FIG. 2A is a process diagram showing a first process, and FIG. 2B is a process diagram showing a second process. FIG. 3C is a process diagram showing a third process.

FIGS. 3A and 3B show moment diagrams of the beam in the step of FIG. 2; FIG.
(B) is a moment diagram in the second step, and (c) is a third view.
It is a moment figure in a process.

FIG. 4 is a plan view showing a second embodiment of the large span roof frame structure according to the present invention.

5A and 5B are diagrams showing a third embodiment of a frame structure of a large span roof according to the present invention, wherein FIG. 5A is a schematic side view, and FIG. 5B is a schematic plan view.

FIG. 6 is a schematic view showing boundary conditions of a leg portion of a beam of a large span roof having a conventional arch structure.

FIG. 7 is a schematic view showing boundary conditions of a leg of a beam of a large span roof with a conventional simple beam frame.

[Explanation of symbols]

 4 Roof frame body 6a ..., 6b ..., 6c ... Supporting rods 7a, 7b, 7c Tension members

Claims (2)

(57) [Claims] 1. A Frame structure of large span roof which covers a large space, before being arranged concentrically on the lower surface of the roof rack構本body made of beams extending radially from the center of the roof Frame body
A connecting beam for connecting the beam is provided, and a plurality of connecting beams are provided on the connecting beam.
Of the roof frame project downward and below the roof frame body
And a tension member is attached to the support rods so as to surround the center portion, and a prestress is introduced into the tension member. 2. The method for constructing a large span roof frame according to claim 1, wherein the roof frame body is constituted by a divided body concentrically divided from a center portion thereof.
The support rods are suspended from these divided bodies, the inner divided bodies are supported at the construction position, and a tension member is attached to the support rods of the divided bodies to introduce prestress,
Thereafter, an outer divided body is arranged on the outer peripheral portion of the inner divided body and joined thereto, and a tension member is attached to a support rod of the outer divided body to introduce a prestress, and from inside to outside. A method for constructing a large span roof frame by repeating the above steps to construct a large span roof.