JP2003268915A - Roof frame - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize a roof frame effective for a roof structure of a building. <P>SOLUTION: A plurality of large span rigid beams 1 are parallelly laid and mutually connected to each other to constitute a roof frame. Respective rigid beams are respectively supported by tensile members such as cables 6 from below. Respective rigid beams are bent to be protrusive downward and both the ends are pin-supported to columns to install between the columns. A plurality of struts 8 are erected with every distance at the lower side of the rigid beams. Respective tensile members are supported at the lower end of the struts to be arranged along the lower side of the rigid beams. The tensile members are tensed to anchor the both ends to the support point P of the column and the rigid beam and introduce prestress into the rigid beam. The upper end of a knee brace provided at the outside of the column is connected to the support point P. The prestress is set so as to offset a horizontal component reactive force brought by the own weight of the roof. A brace member to prevent the sideward falling is installed in the strut. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a roof structure having a composite structure composed of a rigid beam having a large span and a tensile member such as a cable.

[0002]

2. Description of the Related Art There is a suspension structure as a general structure for a large span roof frame. However, in a conventional roof frame structure using a cable as a suspension material,
Deformation against added or eccentric loads that require a large anchorage (usually a huge concrete block) or alternative rigid undercarriage to handle the horizontal reaction to large tensile forces in the cable Various measures are required to ensure the stability of the properties. In order to reduce the horizontal reaction force, it is necessary to increase the sag (hanging material hanging down), so a large space is secured and roof water gradients are reduced. There is a problem that it is difficult to secure it, and when it is applied to the roof of a building, there are many planning and design restrictions.

Further, a roof frame structure having a semi-rigid suspension structure in which a suspension material having bending rigidity is used instead of the cable is also known. According to this, it is easy to secure the structural stability against the deformation property, but it is large. The situation is the same for the processing of horizontal reaction force, and it is not always effective.

[0004]

In view of the above circumstances, the present invention is an effective roof which can reduce horizontal reaction force while being suitable as a roof structure of a building, especially based on a semi-rigid suspension structure. The purpose is to provide a frame.

[0005]

According to a first aspect of the present invention, a plurality of rigid beams having a large span are arranged side by side and connected to each other to form a roof frame, and each rigid beam is connected to a cable from below. Is a composite structure roof frame supported by tensile members such as, and each rigid beam is curved downward convexly, and both ends thereof are pin-supported with respect to the columns and installed between the columns, and the rigid beams A plurality of bundles are provided at intervals on the lower side of each of the tension members, and each tension member is supported by the lower end of the bundle and is arranged below the rigid beam.
Prestress is introduced into the rigid beam by tensioning the tension member and fixing both ends of the tension member to the supporting points of the column and the rigid beam, and the upper end of the walking stick provided outside the column. Is connected to the fixing point of the rigid beam and the tension member.

The invention of claim 2 is characterized in that, in the invention of claim 1, the prestress introduced into the rigid beam is set so as to cancel the horizontal component reaction force generated by the weight of the roof.

The invention of claim 3 is characterized in that, in the invention of claim 1 or 2, the bunch material is provided with a brace material for preventing lateral fall.

[0008]

1 to 4 show an embodiment of the present invention. FIG. 1 is a cross-sectional view of a building (an indoor pool in the illustrated example) adopting the roof frame structure of the present embodiment, and FIG. 2 is a diagram (plan view and elevation view in two directions) showing the roof frame structure.

In the roof frame structure of this embodiment, as shown in FIG. 2 (a), a plurality of span beams 1 are provided (7 in the illustrated example).
Book) arranged side by side, and these girders 1 are connected by girder-direction girders 2 and a large number of girders 3, and a roof frame 4 having a rectangular shape in plan view is constituted by them as a whole, and a roof member 5 is provided on the upper surface thereof.
(See FIG. 1) is attached to form a roof surface, and the roof surface is curved and erected so as to be convex downward as a whole.

The span-direction girder 1 in this embodiment
Is a steel beam having a large span and a predetermined rigidity (hereinafter, the span beam 1 in the span direction is referred to as a rigid beam 1), but the roof frame of the present embodiment basically has the rigid beam 1. Acts as a suspending material to form a semi-rigid suspension structure supporting the entire roof surface, and the rigid beam 1
Is pushed up and supported by a cable (tensile member) 6 from below, and prestress is introduced into the rigid beam 1 by the cable 6.

That is, each of the rigid beams 1 is curved downwardly like the shape of the roof frame 4, and both ends thereof are pin-supported to the columns 7 and are installed between the columns 7. Further, a cable 6 such as a structural spiral rope is arranged below each rigid beam 1.

More specifically, as shown in FIG. 1, a plurality of bundle members 8 (five in the illustrated example) are provided at intervals on the lower side of the rigid beam 1. A cable 6 is disposed so as to be supported by the lower end of the material 8, and the cable 6 is tensioned with a predetermined tension so that both ends thereof are fixed to the end of the rigid beam 1. In this case, the end of the cable 6 is connected to the lower end surface of the rigid beam 1 via a gusset plate, and the core of the cable 6 is connected to the support point P of the rigid beam 1 and the pillar 7.
Cable 6 to rigid beam 1
The fixing point is set so as to substantially coincide with the support point P thereof, so that the prestress due to the tension of the cable 6 is introduced into the rigid beam 1. And
In this embodiment, the prestress introduced into the rigid beam 1 is set so as to cancel the horizontal component reaction force generated by the weight of the roof.

On the outside of the pillar 7 supporting the rigid beam 1, there is provided a cane 9 (back stay) made of a small diameter steel pipe or the like, and the lower end of the cane 9 is a lower structure or a lower structure. It is connected to the ground, the upper end is connected to the top of the pillar 7, and the connecting point is set so as to substantially coincide with the anchoring point of the cable 6 to the rigid beam 1 (that is, the supporting point P described above). Has been done.

The bundle 8 provided below the rigid beam 1 and supporting the intermediate portion of the cable 6 has, for example, FIG.
As shown in (a), a brace member 10 is provided between the lower end of the beam 3 and the beam 3 in the girder direction so that the cable 6 is securely prevented from falling sideways due to the tension force. ing. Alternatively, as shown in (b), the brace material 10 may be provided between two adjacent bundles 8, or the brace material 10 may be provided between the adjacent rigid beams 1 as shown in (c). Reference numeral 12 in FIG. 3 is a stud provided on the roof side of the roof surface as needed.

The construction of the roof frame having the above structure is shown in FIG.
As shown in, the rigid beam 1 is erected between the pillars 7 while being temporarily supported by the temporary gantry 13, the roof frame 4 is assembled, the roof material 5 is attached, and other roof finishing is performed, and then the cable 6 is tensioned. The procedure is to introduce prestress into the rigid beam 1 by fixing. Alternatively, one span unit may be assembled to the ground and installed by a crane. When introducing prestress, one end of the rigid beam 1 is supported as a roller on the stigma of one of the columns 7 to absorb the deformation of the rigid beam 1, or the column base of the column 7 is pinned to the lower structure. I will support it. In addition, since the horizontal force does not act on the pillar 7 at the time of introducing the prestress, the cane 9 may be post-installed. 9 may be constructed so that both ends of the rigid beam 1 are pin-supported to the pillar 7.

The roof frame having the above-mentioned structure is a composite structure of the semi-rigid suspension structure using the rigid beam 1 as a suspension material, and the rigid beam 1 and the cable 6 supporting the rigid beam 1 from below. The tension is introduced into the rigid beam 1 as a prestress, so that the rigid beam 1 and the cable 6 form a self-balancing frame, and the prestress introduced into the rigid beam 1 is the horizontal component reaction force generated by the weight of the roof. Since it is set so as to cancel out, it is a semi-self-contained semi-rigid suspension structure.

That is, as shown in FIG. 4 (b), in a normal time when only the roof weight acts, the cables 6 are balanced by a tensile force acting on the cable 6 and a compressive force acting on the rigid beam 1. Since it is a self-supporting frame, the fulcrum reaction force of the roof frame is generated only in the vertical direction, and no horizontal reaction force is transmitted to the pillar 7 or the cane 9.

Further, as shown in FIG. 4 (c), the rigid beam 1 is out of balance when subjected to an additional load such as snow.
A tensile force acts on both the cable 6 and the cable 6, and at this time, the fulcrum reaction force of the roof frame is also generated in the horizontal direction, and the horizontal reaction force is transmitted to the cane 9 as a tensile force. Function effectively as.

As described above, the roof frame having the above-mentioned structure functions as a self-contained frame when it is under its own weight, and the horizontal reaction force is not transmitted to the lower structure, and it corresponds to the additional load only during additional load such as snow. The horizontal reaction force is only transmitted to the substructure. Therefore, in an ordinary suspension structure, it is necessary to process a large horizontal reaction force including its own weight, so a huge anchorage and a robust substructure are indispensable.
In the above structure, since only the horizontal reaction force at the time of additional load needs to be processed, it is sufficient to provide the cane 9 having a small cross section as the back stay, and the lower structure including the pillars 7 has a horizontal component reaction caused by the weight of the roof. Since it does not receive force, it can be of a small cross section, and the lower structure can be greatly simplified compared to the normal suspension structure.

In addition, in the usual suspension structure, the sag needs to be increased in order to suppress the horizontal reaction force, whereas in the above structure the horizontal reaction force is not so large, so the sag can be set small. Therefore, there are few restrictions in terms of design and design, and it is easy to secure a water gradient on the roof surface.

Further, the roof frame having the above-mentioned structure mainly includes the rigid beam 1 as a suspending member and the roof frame 4 having rigidity.
Since it is configured, it is superior in structural stability against deformation properties compared to the normal suspension structure mainly consisting of cables, and it does not require particularly complicated construction, so the construction period and cost It is also advantageous in that it is extremely rational as a roof frame of a building.

The present invention is not limited to the above embodiment, and various design modifications such as those listed below are possible.

In the above embodiment, the rigid beam 1 is prestressed to cancel the horizontal component reaction force generated by the roof's own weight.
However, in addition to this, it is also possible to set the prestress to a larger value by anticipating the additional load.

In the above embodiment, the prestress is introduced by the cable 6, but if the rigid beam 1 can be supported from below and desired prestress can be introduced, a tensile member such as a steel rod or a steel pipe can be used. It is also possible to adopt instead of the cable 6.

Of course, the shape and scale of the roof surface, the number and spacing of the rigid beams 1 in the roof frame 4, the curvature of the rigid beams 1 and the curvature and the number of tensile members such as the cables 6 provided below the rigid beams 1 and the rigid beams 1. It goes without saying that the intervals and positions of the bundles 8 to be provided, the purpose of the building, the structure of the lower structure, and other specific configurations can be arbitrarily changed.

[0026]

The roof frame structure according to the first aspect of the present invention is based on a semi-rigid suspension structure in which a rigid beam that is convexly curved downward is used as a suspension material, and a rigidity is provided by a tension member disposed below the rigid beam. Since prestressing is applied to the beam, it is superior in structural stability against deformation properties compared to the normal suspension structure, and horizontal reaction force acting on the lower structure can be suppressed, so the process is significantly easier and the sag is set smaller. Since it is possible to do so, there are few design restrictions, it is easy to secure a water gradient on the roof surface, construction is easy, and it is advantageous in terms of construction period and construction cost, and it is extremely rational and effective.

According to the second aspect of the present invention, the prestress introduced into the rigid beam is set so as to cancel the horizontal component reaction force generated by the weight of the roof. Therefore, the horizontal reaction force acts as a self-contained frame under the weight of the roof. Is not transmitted to the substructure, and the horizontal reaction force corresponding to the additional load is transmitted to and processed by the substructure only when there is an additional load such as snow, which greatly simplifies the substructure as compared to the normal suspension structure. be able to.

According to the third aspect of the present invention, since the brace member is provided with the brace member for preventing the bundle member from falling to the side, the bundle member can be surely prevented from falling and structural stability can be secured. it can.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a building adopting a roof frame which is an embodiment of the present invention.

FIG. 2 is a diagram showing a roof frame structure of the same.

FIG. 3 is a partially enlarged view of the same.

FIG. 4 is a diagram for explaining the construction procedure and behavior when a load is applied.

[Explanation of symbols]

1 Rigid beam (large beam in span direction) 4 roof frame 6 cable (tensile material) 7 pillars 8 bundles 9 cane 10 Brace material P support point

Claims (3)

[Claims] 1. A roof having a composite structure in which a plurality of rigid beams having a large span are juxtaposed and connected to each other to form a roof frame, and each rigid beam is supported from below by a tensile member such as a cable. The frame is a frame, and each rigid beam is convexly curved downward, and both ends of the rigid beam are pin-supported to the columns to be installed between the columns. Each tension member is supported by the lower end of the bundle and arranged below the rigid beam, and the tension member is tensioned to support both ends of the column and the rigid beam. Pre-stress is introduced into the rigid beam by being anchored to the point, and the upper end of the cane provided outside the column is connected to the anchor point of the rigid beam and the tension member. A roof frame characterized by. 2. The roof frame structure according to claim 1, wherein the prestress introduced into the rigid beam is set so as to cancel the horizontal component reaction force generated by the weight of the roof. 3. The brace member is provided with a brace member for preventing lateral fall of the bundle member.
Or the roof frame described in 2.