JP2698795B2 - String beam structure - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a novel beam string structure.

(Conventional technology and problems to be solved by the invention) The biggest feature of the stringed beam structure used in the conventional roof structure is that the stress and deformation of the beam material are controlled by introducing prestress by a tensile material such as a cable. is there.

That is, as shown in the example of FIG. 9, the beam string structure has a beam 2 erected between a pair of pillars 1, 1 erected at a predetermined interval and a lower position of the beam 2. , A cable 3 is stretched between the pillars 1 and 1 so that the beam 2 and the cable 3
Is typically connected by an auxiliary member 4 at a substantially central portion. The joint between the beam 2 and the cable 3 and the pair of pillars 1 and 1 is, for example, one at a pin fulcrum 5 and the other at a roller. The fulcrum is 6.

Therefore, the tension generated in the cable 3 by the weight of the beam 2 can be borne as an axial force on the beam 2 itself, and since it is a so-called self-anchoring type, no anchor is required. With the introduction,
This has an advantage that an optimum stress distribution can be obtained for the beam 2.

However, in the stringed beam structure, it may be difficult to stretch the tension member 3 such as a cable between both ends of the beam 2 depending on the conditions of the constituent members. The part may be connected to the intermediate part of the beam 2.

Then, the beam 2 at the site where the ends of the tensile members 3 are connected
In this case, stress was concentrated, and there was a structural problem.

Then, this invention was proposed for the purpose of providing the string string structure which can solve the said subject.

(Means for Solving the Problems) In order to achieve the above-mentioned object, in the beam string structure according to the present invention, a beam member and a tension member provided below the beam member are connected by a plurality of bundle members. In a beam string structure having a support member that supports both ends of the beam member, the tension member includes a first tension member and a second tension member, and the most stressed member located on the support member side of the beam member. First in the area to concentrate
The first bundle member is attached from a bottom of a central bundle member attached to a substantially central portion of the beam member to a top of the first bundle member via the bottom of each bundle member disposed at an intermediate position. A tension member is stretched and an upper portion of a support member that supports both ends of the beam member from the top of the second bundle member adjacent to the center of the first bundle member through the bottom of the first bundle member. , The second tension member is stretched.

In a case where the beam member is arranged in a mountain shape with a central portion between the support members as a vertex to form a roofed string beam, the substantially central portion of the beam member includes the center as a compression material. It is desirable to provide a central bundle that functions as a tension member along with the bundle members.

(Embodiment) Hereinafter, a preferred embodiment of the present invention will be described with reference to the drawings.

1 to 8 show an embodiment in which the beam string structure according to the present invention is applied to a roof structure. The roof beam string structure T according to this embodiment includes a beam member 10, a bundle member 11, It comprises a first tension member 30 and a second tension member 31.

In the present embodiment, the pair of beam members 10, 10 are disposed in a mountain shape with the central portion between the support members 13, 13 (one not shown) standing opposite to each other at a predetermined span as a vertex. The beam members 10, 10 and the first tension member 30 and the second tension member 31 disposed below the beam members 10, 10 are connected by a plurality of bundle members 11 to form a roof clad beam structure T. Has formed.

In this embodiment, the tension member is composed of the first tension member 30 and the second tension member 31 as described above, and is located on the support member 13 side of the beam member 10 as shown in FIG. The first bundle member 11a is attached to a portion where the ends of the first tensile members 30 are connected, that is, a portion where the stress is concentrated most.

Thus, the center of the third bundle member 11d and the second bundle member 11c disposed at intermediate positions from the bottom of the central bundle member 11b and the central bundle member 61 attached to the substantially central portion of the beam member 10 in the longitudinal direction. The first tension member 30 is stretched from the bottom to the top of the first bundle member 11a.

That is, as shown in FIG. 5 and FIG.
Numeral 61 is formed as a tension member in which two strip-shaped steel frame members 61a are combined, and the lower end of the central bundle member 61 is joined to a ring-shaped connection plate 70. A fastening device 62 provided at an end of the tensile member 30 is fixed by welding or the like.

The bottoms of the pair of central bundle members 11b are tightly fixed to a Y-shaped plate 71 formed integrally with the connection plate 70.

In this embodiment, the first tension member 30 is formed of a threaded rebar material, and the tightening device 62 includes a coupler 63 and a pair of nuts 64, 64. Since the screw portion 65 formed at the end of the nut 30 is screwed to the nut 64, a prestress can be introduced into the first tensile member 30 by tightening the nut 64.

In addition, as shown in FIG.
A similar tightening device 62 is provided at an intermediate position of 30,
Further, as shown in FIG. 7, a connecting hardware 56 for tightening the top of the first bundle member 11a and the beam member 10 has a similar fastening device provided at the other end of the first tension member 30. The first tension member 30 can be prestressed by the fastening devices 62 in the same manner as described above.

On the other hand, as shown in FIG. 1, the first bundle member 11a extends from the top of the second bundle member 11c adjacent to the center of the first bundle member 11a.
The second tension member 31 is stretched over the column member 40 of the support member 13 via the bottom of the second tension member 31.

That is, as shown in FIG. 3, one end of the second tensile member 31 is
As described above, the first connection member 17 is fixed to the plate 17b of the first connection member 17 disposed at the upper end of the second bundle member 11c by bolting, and as shown in FIG.
It is sandwiched and extended by a pair of substantially U-shaped bolts 25 provided on the connection hardware 17b, and the other end is fixed to a joining plate 49 provided at an upper end of a column member 40 constituting the support member 13 by bolt joining. Have been.

In the present embodiment, the second tensile member 31 is also formed of a threaded reinforcing material, and as shown in FIGS.
At a middle position of the tension member 31, a turnbuckle as a fastening device 66 is provided at two places.
Thus, a prestress can be introduced into the second tensile member 31.

As shown in FIG. 7, the upper end of the diagonal member 45 constituting the support member 13 is connected to the connection hardware 56.

That is, as shown in FIG. 7 and FIG. 8, end metal pieces 55 are tightly fixed to both ends of the diagonal member 45 made of laminated wood with bolts and nuts. The end piece 55 at the upper end is similarly pin-connected to the connection piece 56 by the pin material 54, as shown in FIG.

In this embodiment having such a configuration, the first tensile member
In the configuration of only 30, the stress concentrates on the beam member 10 at the upper end position of the first bundle member 11 a to which one end of the first tensile member 30 is connected. (2) The tension member 31 is disposed, the turnbuckle 66 as a fastening device is tightened, and a predetermined tension is introduced into the second tension member 31, whereby the first bundle member 11a presses the beam member 10 upward. Therefore, when tension is introduced to the first tension member 30, the stress acting on the beam member 10 at the upper end position of the first bundle member 11a from the first tension member 30 is canceled, and the beam member at that position is canceled. 10 can be reduced, and in cooperation with the operation of the diagonal member 45, a rational structure can be achieved.

However, by adjusting the magnitude of the tension introduced into each of the tensile members 30 and 31, it is possible to control the stress distribution and the amount of deformation on the roof surface. Large span structures can be economically formed using small cross-section structural materials.

In addition, by disposing the central bundle member 61b, which can function as a tension member, together with the central bundle member 11b at the central portion of the beam member, the amount of deformation of the entire beam structure can be significantly reduced.

In the present embodiment, the beam member 10 is formed as shown in FIG.
As shown in FIG. 2 which is an A sectional view, a beam element 14 (18 cm square in this embodiment) of a relatively small cross section made of glued laminated wood is connected and integrally formed in an inverted V-shape.

That is, in this embodiment, five beam elements 14 are combined in an inverted V-shape, and are mutually united by four bolts 15 and nuts 16 to be integrated.

The bundle member 11, as shown in FIG.
The beam member 10 is placed and joined on the top of the bundle member 11 in a pantograph shape (diamond shape) corresponding to the cross-sectional shape of.

Further, the bundle member 11 is formed mainly of a glued laminated material similarly to the beam member 10, and in the present embodiment, the bundle member 11 has a smaller cross section (150 cm square in this embodiment) than the beam element 14.
The bundle element 20 is formed by binding and integrating the four connecting hardware.

That is, the first connection hardware 17 is disposed at the top, the second connection hardware 18 is disposed at the bottom, and the third connection hardware 19 is disposed at both right and left corners.
However, each end is tightened and fixed by bolts and nuts (not shown) at the positions of a predetermined number of mounting holes 21 formed in the connection hardware 17, 18, and 19, and integrated. Things.

In addition, as shown in FIG. 3 and FIG.
7, 18, and 19 each have a flat plate-shaped main body portion 17a, 18a, 19a embedded and bonded at the center position of the end of the bundle element, and are bonded so that the main body portions are not visible from the outside.

In addition, in the first metal fitting 17, as shown in FIG. 3, plates 17b and 17c serving both for positioning and reinforcing the ends of the bundle element 20 are formed integrally with the main body 17a. One end 31a of the second tension member 31 is connected and fixed to the middle left plate 17b as described above.

Further, as shown in FIGS. 2 and 3, a pair of joining plates 17d are formed in a V-shape from the upper ends of the plates 17b and 17c, and extend from the upper ends of the plates 17b and 17c. The joining plate 17d is sandwiched between the joining portions to perform the bolt joining.

Therefore, in this embodiment, four bolt through holes 22 are formed in the joining plate 17d as shown in FIG.

As shown in FIG. 2, a reinforcing plate 23 is in contact with the beam element 14 located at the end of the beam member 10, thereby preventing the beam element 14 from being entrapped at the time of fastening.

Next, in the second connection metal part 18, as in the case of the first connection metal part 17, plates 18b and 18c serving both for positioning and reinforcing the end of the bundle element 20 are formed integrally from the main body part 18a as shown in the drawing. Further, from the upper ends of the plates 18b and 18c, a pair of joining plates 18d are formed to extend in a V-shape.

Two mounting holes 24 are formed at the same position in each of the pair of joining plates 18d, and two substantially U-shaped bolts 25 are formed in the mounting holes 24 as shown in FIGS. Nut 26
And the first tension member 30 is gripped by the substantially U-shaped bolt 25.

Further, in the third connection metal 19, as shown in FIG. 4, plates 19b and 19c serving as both positioning and reinforcing of the end of the bundle element 20 are formed integrally with the main body 19e, and furthermore, as shown in FIG. A pair of joining plates 19d are formed integrally with the inner end of the main body 19a.

Thus, between the left and right joining plates 19d, a tension device 2
7 are arranged.

In the present embodiment, the tensioning device 27 is composed of a pair of threaded reinforcing members 28 and a turnbuckle 29, and one end 28a of both threaded reinforcing members 28 is welded between the pair of joining plates 19a by means such as welding. The screw portions formed respectively at the other ends 28b are screwed and connected to the pattern buckles 29, respectively.

Therefore, by rotating the turn buckle 29 in a predetermined direction, the pair of third connection hardware 19 can be tightened in a direction in which they come close to each other.

The other bundle members 11 have the same configuration as described above.

It should be noted that the present invention is not limited to the above embodiment, and the number of the bundle members 11 and the number of the beam elements 14
Can be arbitrarily set according to conditions.

In the present embodiment, the tensile members 30 and 31 are formed of a reinforcing steel material. However, other than the above, it is also possible to use a cable, a shaped steel or the like according to design conditions and the like.

Further, the beam member 10, the bundle member 11, the support member 13 and the like can be made of a general steel frame material or the like without using a glued laminated material as in the above-described embodiment. It goes without saying that various modifications can be made without departing from the scope.

(Effect of the Invention) The present invention is configured as described above, and by applying a predetermined tension to the second tension member provided as described above, the first tension member is applied to the beam member at the upper end position of the bundle member. The applied stress can be offset to reduce the load on the beam member at the position, and a rational structure can be achieved by using a member having a smaller cross section than before.

In addition, when a central bundle member that can function as a tension member is provided in the center of the beam member together with the central bundle member, the amount of deformation of the entire beam structure can be significantly reduced, and a more rational structure and It is possible to do.

However, by adjusting the magnitude of the tension introduced into the tensile member, it is possible to control the stress distribution and the amount of deformation on the beam member. The structure can be formed economically.

[Brief description of the drawings]

1 to 7 show an embodiment of the present invention. FIG. 1 is an explanatory view of a main part showing a schematic configuration of a stringed beam structure according to this embodiment, and FIG. 2 is a beam member and a bundle member. 3 is a side view, FIG. 4 is an explanatory view showing a tensioning device, FIG. 5 is a description of a main part showing a structure of a central portion of a structure, and FIG. 6 is a cross-sectional view thereof. FIG. 7 is an explanatory view showing the structure of the second tension member and the support member, FIG. 8 is a sectional view of the diagonal member in FIG. 7, and FIG. 9 is an explanatory view showing a conventional stringed beam structure. 10 beam member, 11 bundle member, 11a first bundle member, 11b central bundle member, 11c second bundle member, 13 support member, 30 first tensile member, 31 … Second tensile material, 40… Column material, 45… Diagonal material, 61… Center bundle material, 62, 66 …… Tightening device.

Claims (3)

(57) [Claims] 1. A beam string structure comprising a beam member and a tension member disposed below the beam member connected by a plurality of bundle members, and having a support member for supporting both ends of the beam member. The material is composed of a first tensile member and a second tensile member. A first bundle member is attached to a portion of the beam member on the support member side where the most stress is concentrated, and is attached to a substantially central portion of the beam member. The first tension member is stretched from the bottom of the central bundle member to the top of the first bundle member via the bottom of each bundle member disposed at an intermediate position, and the first bundle member is stretched. The second tension member is stretched from the top of the second bundle member adjacent to the center side to the top of the support member supporting both ends of the beam member via the bottom of the first bundle member. The beam string structure. 2. A patent wherein the beam member is disposed in a mountain shape with a central portion between the support members as an apex, and the beam member, the bundle member, and the tensile member form a roof string beam. The beam string structure according to claim 1. 3. The beam string according to claim 2, wherein a central bundle member functioning as a tension member is disposed substantially at a central portion of the beam member together with the central bundle member as a compression member. Structure.