JPH04102644A - Building furnished with large span of roof frame - Google Patents

Abstract

PURPOSE:To make a lightweight truss beam by installing a steel material receiver to a lower of a truss beam, providing a PC steel rod from the steel material receiver to the upper end of pillar steel of each roof frame, and fixing them after the bending of the beams by the constant load of the roof members and the like is generated. CONSTITUTION:Steel farmed pillars 2 are erected, truss beams 1 are extended between the upper ends of the pillars 2, both ends of PC steel rods 4 are inserted into the oblique holes of the steel framed pillars 2, and both ends of the upper and the lower chord members 1a and 1b of the truss beams 1 are welded to the steel framed pillars 2 to compose roof frame units 10. Then, roof frame units 10 are arranged parallel, combined by girders 5, purlins and the like, and roof members are installed thereon. And after a bending is generated to the truss beams 1 by the constant load of the dead load of the members, nuts are screwed on the screws at both ends 4a of the PC steel rods 4, and the ends of the PC steel rods 4 are fixed to the upper ends of the iron frame pillars 2. Consequently, the truss beams 1 are made light in weight, and the consumption of steel frames can be reduced.

Description

[Detailed Description of the Invention] Industrial Field of Application The invention of this application is directed to a building with a large-span roof frame;
In particular, when the load acting on the roof increases in the short term due to snowfall, etc., P
This invention relates to a building equipped with a large-span roof frame supported by C steel.

BACKGROUND OF THE INVENTION Recently, even in areas with heavy snowfall, steel frame buildings with large spans and gently sloped roofs have been constructed.

For large-span steel-framed buildings, a large-span roof frame is formed by fixing both ends of a truss beam to the top of a pair of steel columns, and multiple roof frames are built in parallel at intervals, and each roof frame is They are connected by girder materials, bean materials, etc., and roof materials are attached on top of the girder materials, haze materials, etc. And in designing it,
Steel columns, steel truss beams, etc. are designed to take into account snow loads (450 to 600 kg/rrr) during snowfall.

Problems to be Solved by the Invention In conventional steel-framed buildings with large-span roofs, the snow load is anticipated and analyzed and steel columns, steel truss beams, etc. are formed, which requires a large number of steel frames for the truss beams. This has the disadvantage that the building becomes expensive.

The problem to be solved by this invention is to provide a building equipped with a large-span roof frame that does not have the above-mentioned drawbacks. The object of the present invention is to provide a building equipped with a roof frame.

Means for Solving the Problems The present invention employs the following configuration as a means for solving the problems described above.

The structure of this invention is that a large span roof frame is formed by fixing both ends of a truss beam to the top of a pair of steel columns, a plurality of roof frames are built in parallel at intervals, and each roof frame is made of girders. In a building with a large-span roof frame, which is connected with porcelain materials, etc., and the roof material is attached on top of the girders, porcelain materials, etc., the middle of the lower chord of the truss beam of each roof frame Two pieces of steel are attached at intervals, and the prestressed steel is attached to the upper end of one of the steel columns of each roof frame, and the lower chord of the truss beam of each roof frame. After the truss beam is installed across the upper end of the other column steel frame, and after the truss beam of each roof frame is deflected due to the constant load of the own weight of the roofing material, etc., when no tension is applied to the PC steel material. , in a building with a large-span roof frame characterized by both ends of the prestressed steel material being fixed to the top of a steel column.

The column steel frame is constructed to be able to bear constant loads due to the weight of truss beams, roofing materials, etc., wind loads, earthquake loads, and short-term increased loads such as during snowfall. The truss beam shall be constructed so that it can bear the constant load due to the weight of the truss beam, roofing material, etc., wind load, and earthquake load. The lower chord of the truss beam is configured so that it can also bear the load of the wiring rack and maintenance passage for lighting equipment.

PC steel is a general term for high-strength steel used as a tension material for precast concrete, and there are three types: PC steel wire, PC steel stranded wire, and PC steel rod.

In a preferred embodiment of the present invention, a PC steel bar is used as the PC steel material, but a PC steel wire or a PC steel stranded wire can also be used.

Although the PC steel members that carry short-term increased loads may be placed on only one side of the roof frame truss beam, in preferred embodiments they are placed on both sides of the roof frame truss beam. In addition, two or more PC steel materials can be arranged on one side of the truss beam.

The amount of steel material is constructed so that one steel material can support the PC steel materials normally arranged on both sides of the truss beam. That is, the width of the supporting part of the body is made larger than the width of the lower chord member, and the holder tube or the holder piece is attached to the supporting part protruding from the lower chord member on both sides.

The end of the PC steel material is fixed to the top of each steel column without any tension being applied to the PC steel material after the truss beam is deflected due to constant load due to the weight of the truss beam, roofing material, etc. Then, when an increased load such as a snow load acts on the roof, tension is generated in the PC steel due to the difference in elongation between the steel that makes up the truss beam and the steel that makes up the PC steel, causing tension between the top chord and the PC steel. The increased load is supported by the inverted trapezoidal structure formed by.

Note that the truss beams are formed by removing predetermined blanks in consideration of deflection during snow accumulation.

Function: In a building equipped with a large-span roof frame according to the present invention, two steel members are attached at intervals in the middle of the lower chord of the truss beam of each roof frame, and a prestressing steel member is attached to one side of each roof frame. Each steel material attached to the upper end of the column steel frame and the lower chord member of the truss beam of each roof frame is installed across the body and the upper end of the other column steel frame of each roof frame, and the truss beam of each roof frame, the roof material After the truss beam is deflected due to constant loads such as self-weight, P
Since both ends of the C steel material are fixed to the top of the steel column, short-term increased loads such as snow loads can be supported by the PC steel material. Therefore, the weight of the truss beam, which always bears the load, can be reduced.

Embodiment An embodiment of a building according to the present invention will be described with reference to FIGS. 1 to 6.

FIG. 1 shows an example in which two unit roof frames 10 are connected in the longitudinal direction and have a single central steel column, and the unit roof frame 10 consists of a truss beam 1, a column steel frame 2, Uke is body 3,
The truss beam 1 is made up of PC steel bars 4, etc. It is constructed to be able to sufficiently support the normal load consisting of the weight of M equipment, etc.

The truss beam 1 is constructed by joining a gusset plate 1e to an upper chord member 1a and a lower chord member 1b by welding or the like, and placing a strut member 1c and a diagonal member 1d between the upper chord member 1a and the lower chord member 1b.
The ends of the lower chord members 1b and 1b are joined to the gusset plate 1e by welding or the like, and a predetermined blank (for example, Loom
) to form. As the upper chord material 1a, for example, H
A shaped steel is used, and the lower chord member 1b is, for example, a steel material formed by overlapping the sides of two L-shaped steels and joining them to form an upper-shaped cross section.

The truss beam 1 is formed so that the lower chord member 1b is horizontal and the upper chord member 1a is slightly inclined with respect to the horizontal.
To make it possible to form a roof with a gentle slope on top of a.

The column steel frame 2 is made of H-beam steel that can sufficiently bear normal loads and short-term increased loads such as snow loads. The column steel frames 2 on both sides have the same length, and the central column steel frame 2 is slightly longer than the column steel frames on both sides.

As shown in FIG. 2 (A, ), a steel plate 2a is interposed between the flanges of the H-shaped steel above the steel column 2 at one interval, and the periphery of the steel plate 2a is welded to the flange and web. The upper part of the steel column 2 is reinforced. A seat 2b for receiving a nut is welded to the outside of the inner flanges on both sides of the upper web of the steel column 2 located on both sides, and a diagonal hole is made in this seat 2b through which the PC steel sill 4 is passed.

Nut-receiving seats are also welded to the inside of the flanges on both sides of the upper web of the central steel column 2, and diagonal holes are also made in these seats to allow the PC steel rod 4 to pass through.

As shown in Fig. 3, the steel rod support body 3 consists of six steel plates 3a, 3b that are longer than the width of the lower chord member 1b.
are connected by welding or the like in a lattice shape to create a support part 3c, arc-shaped recesses are formed at the lower part of both sides of each steel plate 3a constituting this support part 3c, and a short tube body is bent into an arc shape. The receiver is formed by applying the tube 3d to the recessed portion of each steel plate 3a, and by welding the tube 3d to each steel plate 3a. Note that instead of the tube 3d, a piece of the receiver formed by bending a short gutter-like body with a semicircular cross section into an arc shape may be used.

The PC steel rod 4 is constructed by cutting a PC steel rod into a predetermined length,
Threaded portions are formed at both ends 4a. And for example,
Bend the PC steel rod 4 into a shape that roughly matches the shape of the ACDB in Figure 5, and insert the two steel bar supports into the holes in the pipe 3d of the body 3.
Pass the steel rod 4 through.

As shown in FIG. 2(B), the lower chord member 1b of each truss beam 1
PC steel rods 4 are placed at intervals on the bottom surface at an appropriate location in the middle.
A suitable position for fixing the body 3 through the steel holder 1c is the lower part of the lever 1c.

Next, the steel column 2 is erected, the truss beam 1 is passed between the upper ends of the steel column 2, and both ends of the PC steel beams 4 are passed through the diagonal holes of the steel column 2 through which the PC steel beams 4 are passed. Both ends of the upper chord member 1a and the lower chord member 1b are welded to the steel column 2 to form a unit roof frame 10.

A plurality of unit roof frames 10 are arranged in parallel in the same manner as described above. Then, each unit roof frame 10 is connected to a girder 5,
They are connected using haze materials, etc., and roofing materials are attached on top of the girder material 5, haze materials, etc.

After the truss beam 1 is deflected by the constant load due to its own weight of the roofing material, etc., both ends 4 of the PC steel bar 4 are
Screw the nut 4b into the threaded part of a, stop tightening the nut 4b while no tension is applied to the PC steel bar 4,
The end of the PC steel bar 4 is fixed to the upper end of the steel column 2. That is, when a normal load is acting on the truss beam 1,
When no tension is generated in the PC steel bar 4 and a normal load and a short-term increased load such as snow load act on the truss beam 1,
Tension is generated in the PC steel rod 4, so that the PC steel rod 4 can bear a short-term increased load.

In addition, the steel rod body 3 is fixed to the lower chord member 1b of the truss beam 1, and then the truss beam 1 is fixed to the steel column 2, and the lower chord member 1
The amount of steel rod fixed at b is determined by passing the PC steel rod 4 through the pipe 3d, bending the PC steel rod 4, and connecting both ends of it to P of the steel column 2.
It may be made to pass through the hole through which the C steel bar passes. In addition, when using a piece of the bridge formed by bending a short semicircular cross-section gutter-like body into an arc shape instead of the pipe 3d, a long PC steel rod 4
Since it is only necessary to engage the middle part of the holder with the piece, and there is no need to pass it through the hole, the work of arranging the pc* rod 4 becomes very easy.

Since the end of the PC steel bar 4 is fixed to the top of the steel column 2 within a range where no tension is applied to the PC steel bar 4 after deflection occurs due to constant load, short-term increased loads such as snow loads etc. On the other hand, when the truss beam 1 tries to bend further, the difference in elongation between the steel material (SS-41) constituting the truss beam 1 and the steel material (PC material) constituting the PC steel bar 4 causes the PC steel bar 4 to bend. Tension is generated in the structure, and the stress can be transmitted through an ABCD inverted trapezoidal structure formed by the upper chord member 1a and the PC steel beam 4 as shown in FIG.

Effects of the Invention In a building equipped with a large-span roof frame according to the present invention, two steel bodies are attached at intervals in the middle of the lower chord of the truss beam of each roof frame, and a PC steel body is attached to each roof frame. Each steel material attached to the upper end of one column steel frame and the lower chord of the truss beam of each roof frame is arranged to extend across the body and the upper end of the other column steel frame of each roof frame. truss beam,
After the truss beam is deflected due to the constant load of the roofing materials, etc., both ends of the PC steel are fixed to the top of the steel column with no tension applied to the PC steel, and short-term loads such as snow loads etc. Since the increased load can be borne by the PC steel material, the weight of the truss beam can be reduced, and the amount of steel used can be reduced (approximately 20% reduction in the total amount of steel). Therefore, even in areas with heavy snowfall, large spans (
For example, a building with a gently sloped roof (20 m to 30 m) can be constructed at low cost.

This invention fixes both ends of the PC steel material to the upper end of the steel column,
Since it is not fixed to the truss beam itself, there is no need to strengthen the truss beam itself. Therefore, a simple structure is adopted in which both ends of the PC steel are fixed to the upper end of the steel column, and the middle part of the PC steel is attached to the lower chord of the truss beam at a distance, so that the two steel members are supported by the body. Since only an additional load is required, a building capable of withstanding short-term increased loads such as snow loads can be provided at low cost. Furthermore, no special equipment or equipment is required.

By arranging PC steel materials on both sides of the truss beams of the roof frame, the PC steel materials can reliably bear large short-term increased loads.

[Brief explanation of drawings]

Figures 1 to 6 are detailed explanations of the present invention, in which Figure 1 is a front view of the unit roof frame and Figures 2 (A) and (B).
3(A) is a front view showing an enlarged view of the main parts of FIG. 1, FIG. 3(A) is a side view of the body, and FIG. 3(B) is a plan view of the body. (C) shows the amount of steel rods in the front view of the body, and Fig.
The steel rod sectioned at 1-1 in Figure (B) is a side view showing the relationship between the body and the lower chord, and Figure 5 schematically shows the inverted trapezoidal structure formed by the upper chord and the PC steel rod. FIG. 6 is a plan view of a building equipped with a large-span roof frame showing the relationship between truss beams and steel columns. In the figure, 1 is a truss beam, 1a is an upper chord member, 1b is a lower chord member, 2
is the column steel frame, 2b is the seat that receives the nut, 3 is the steel rod amount,
3c is a support part, 3d is a pipe, 4 is a PC steel beam, 5 is a girder, and 10 is a unit roof frame. Patent applicant: Takenaka Corporation

Claims (1)

[Claims] 1. A large-span roof frame is formed by fixing both ends of a truss beam to the top of a pair of steel columns, and a plurality of roof frames are built in parallel at intervals, and each roof frame In a building with a large-span roof frame, in which the roof members are connected with girders, bean members, etc., and the roofing material is attached on top of the girder members, bean members, etc., the bottom chord of the truss beam of each roof frame is Two steel receivers are installed at intervals in the middle, and the prestressed steel members are attached to the upper end of one of the steel columns of each roof frame, the lower chord of the truss beam of each roof frame, and each of the steel receivers and each roof frame. After the truss beam is installed across the upper end of the other column steel frame, and after the truss beam of each roof frame is deflected due to the constant load of the own weight of the roofing material, etc., when no tension is applied to the PC steel material. , P
A building with a large-span roof frame characterized by having both ends of C steel fixed to the top of steel columns. 2. In a large-span roof structure formed by fixing both ends of a truss beam to the top of a pair of steel columns, two steel receivers are installed at a distance from each other in the middle of the lower chord of the truss beam, and the PC steel is installed across the upper end of one steel column of the roof frame, each steel receiver attached to the lower chord of the truss beam, and the upper end of the other steel column of the roof frame, and the truss beam of the roof frame, roofing material, etc. A large-span roof characterized in that both ends of the prestressed steel are fixed to the top of the steel column without any tension being applied to the prestressed steel after the truss beam is deflected due to the constant load of its own weight. Frame. 3. A building equipped with a large-span roof frame according to claim 1 or 2, characterized in that prestressed steel members are arranged on both sides of the truss beams of the roof frame.