JPH08128115A - Spherical joint for space truss and member-jointed space truss structure using the joint - Google Patents

Abstract

PURPOSE: To reduce an axial force to be transmitted to a connection spherical joint between a chord member and a brace or the like, and simplify the structure of the spherical joint to facilitate the joint work on the site. CONSTITUTION: In a spherical joint 2, a cylinder-shaped hole 2a is formed which allows a chord member 1 to pass through the center of a solid sphere, while a screw hole 2c is installed to a solid part 2b around the cylinder-shaped hole 2a so as to thread a connection bolt 3A on one hand. The spherical joint 2 is preliminarily welded with the chord member 1. A brace 4 is fastened with a bolt by using a joining device 3 on a truss construction site. The spherical joint 2 allows the chord member 1 to be passed, which prevents an axial force acting on the chord member from being directly exerted on the spherical joint 2. Therefore, in the manufacture of the joint 2, it is sufficient if the joint 2 can sustain a small axial force transmitted from the brace 4. By such a construction simplification of the structure of the sphere-shaped joint 2 and reduction in the weight can be attained and onsite welding work may be eliminated and it facilitates assembling work of truss structure by a small bolt-connecting work.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spherical joint for a space truss and a space truss structure joined by members using the same, and more specifically, to a long string material adopted in a large span building for fixing through. , A structure of a spherical joint that enables a space truss to be constructed by inserting a diagonal member at a position determined by a joining device using a joining bolt, and a diagonal member between two fixed spherical joints The present invention relates to a three-dimensional truss structure with improved workability when interposing a truss. This is applied to a roof structure composed of space trusses, in particular, large-span structures such as flat roofs, sloping mountain roofs and arch roofs, and tower truss structures.

[0002]

2. Description of the Related Art When a large-span structure, tower-shaped structure, or the like is formed into a truss structure by using a large number of pipe materials, etc., a system truss system in which individual structural materials are sequentially connected by bolts or all structures It is common to adopt one of the methods of welding by welding the materials at the joints.

In the former case, a joint suitable for connection work on site is provided in advance to each structural material in the factory, and as a result, the material can be easily carried into the construction site and connection using bolts is performed. Since it is a form, it has the advantages of higher workability and less labor than welding. Since the latter is a connection form by in-situ welding, the structural material is hardly processed, and it is not necessary to cut a chord material having a large cross section at each joint portion like the former. Therefore, the material cost and the processing cost can be reduced, and the continuous string material can ensure the transmission of a large axial force, and the mechanical calculation for truss design can be simplified.

However, in the above-described system truss structure, when a large-area chord member 1 such as a thick-walled steel pipe is used, it is necessary to use bolts having a very large diameter of 75 mm to 90 mm for connecting the structural members. There are many. And even if you use extra-thick bolts, it may not be possible to even give sufficient proof strength that matches the strength required for the truss, and the work of tightening large-diameter bolts on-site still requires a lot of effort. In addition, the use of high-tensile bolts leads to high material costs, and it is necessary to subject the bolts to advanced heat treatment, which eventually leads to expensive joints.

In the case of welding, the assembly structure is as shown in FIG. 6, for example. This is because it is not easy to transport pre-assembled items in a vehicle, so all components are directly welded in the field. That is, after arranging the long chords 21, the ends of the thin diagonal members 22 are attached to the chords 2
The periphery 22a is welded to the abdomen 1 of the like. However, it is difficult to accurately position each member on-site, and the welding work is extremely time-consuming, requiring a large number of welders with high-accuracy assembly technology and advanced skills, and constructing an inexpensive truss. Not suitable for.

FIG. 7 shows an example of a space truss in which a long chord member 31 used for a large span building is penetrated and fixed to a spherical joint 32, and the end of a diagonal member 33 is welded to the spherical joint 32. Is. Such a structure is disclosed, for example, in Japanese Utility Model Laid-Open No. 64-112.
As described in Japanese Patent Publication No. 03, No. 03 gazette, the spherical joint 32 is a spherical shell, and the two holes 3 through which the chord member 31 penetrates the thin shell thereof.
2a, 32a are provided, and the perimeter of each opening 32b,
32b is welded to the chord member 31, and the diagonal member 33 is butt welded to the surface of the thin shell portion. In this example, as in the case of FIG. 6, the effect of transmitting the axial force of the chord member 31 is enhanced, and the axial force is less likely to reach the spherical shell 32.

[0007]

When the spherical shell body 32 penetrating the chord member 31 is arranged at the joint with the diagonal member 33 in this way, the spherical shell body 32 has a large axial force as described above. It has no effect. Therefore, it is not necessary to give excessive strength to the spherical shell 32 to which the diagonal member 33 that does not transmit an axial force as large as the chord member 31 is attached, and the structure thereof can be simplified and the weight thereof can be reduced. However, in the structure shown in FIG. 7, even if the spherical shell 32 can be previously welded to the chord member 31 at the factory, the joining of the end portion 33b of the diagonal member 33 still has to rely on in-situ welding. After all, there is an unavoidable difficulty in reducing construction efficiency.

By the way, in JP-A-3-286055, the end face of each pipe material is welded to the surface of a thin spherical shell to form a long chord, and a plurality of pieces are formed on the remaining surface of the spherical shell. An example of an octaplate joint structure is described in which diagonal members are butt-welded and joined as if the spherical members support the spherical shell.

This is a structure in which, for example, two opposite end portions of two Warren space trusses arranged at the same height so as to extend left and right are connected by a keel truss having a thick keel member joined to a spherical shell. ing. The plurality of diagonal members constituting the keel truss are fastened to each warren space truss by a joining device using joining bolts, and are joined to the spherical shell fixed to the keel member by welding. Also, unlike the structure described above, keel truss keel truss (chord material) can be inserted into the spherical shell as shown in FIG. 7, but the diagonal member is also butt welded to the surface of the thin spherical shell. Will be. In any of the examples, from the viewpoint of workability, there is substantially no difference from the case of FIG. 7.

By the way, in the spherical joint made of the above spherical shell, even if the diameters of the diagonal members are different, the welding forms on the spherical shell surface are the same. Generally, at the end portion of the truss structure, the force acting on the diagonal member tends to be larger than that at the intermediate portion. Therefore, when the spherical shell has a thin structure as described above, the spherical joint at the end portion is easily deformed. By the way,
At this end part, the chord material can be made slightly thinner, so if the diameter of the spherical shell is intentionally reduced, the deformation of the spherical shell can be suppressed, but conversely, the tip of the thick diagonal member should be There is a problem that the space for welding cannot be secured.

The present invention has been made in view of the above problems, and an object thereof is to perform welding work for connecting a spherical joint and a diagonal member while adopting a form in which a chord member is penetrated through the spherical joint. It can be eliminated to significantly improve the welding work efficiency and significantly reduce the work effort, and even if a large axial force acts on the chord material, it does not greatly affect the spherical joint, and the structure of the spherical joint can be simplified. It is intended to provide a spherical joint for a space truss that realizes weight reduction and cost reduction thereof, and a space truss structure in which members are joined using the spherical joint.

[0012]

The present invention is applied to a spherical joint capable of forming a space truss by penetrating and fixing a long chord member employed in a large span building. As for the feature, referring to FIG. 1, the spherical joint 2 has a cylindrical hole 2a for allowing the chord member 1 to penetrate through the center of a solid sphere.
And a bolt for fixing the diagonal member or system truss member 4 between the spherical joints 2 and 2 (see FIG. 2) by the joining device 3 to the solid portion 2b around the cylindrical hole 2a. Since 3A is screwed, a screw hole 2c extending from the spherical surface toward the center of the spherical joint 2 is formed.

The invention of the space truss structure in which the members are joined by using the spherical joint is such that the joining bolt 3A is screwed into the screw hole 2c of the spherical joint 2 which is fixed in advance by penetrating the chord member 1 into the cylindrical hole 2a. The device 3 fixes the diagonal member or the system truss member 4 between the spherical joints 2 and 2.

According to the third aspect of the present invention, referring to FIG. 5, a large-diameter perforated spherical joint 2 having a cylindrical hole 2a having a large diameter for penetrating a thick chord member 1 at an intermediate portion of a truss structure is provided. used. On the other hand, at the end portion of the truss structure, it is thicker than the diagonal member or the system truss member 4 which is connected to the chord member 1 and which penetrates the thinner chord member 1A and is bolted to the large diameter perforated spherical joint 2. That is, the small diameter holed spherical joint 2A in which the large diameter screw hole 2d to which the member 4A can be attached is formed in the solid portion 2f is used.

[0015]

The chord member 1 is passed through the spherical joint 2 in advance, and is integrated in the factory by welding. The spherical joint 2 is provided with a cylindrical hole 2a in the center of a solid sphere, and an appropriate number of screw holes 2c for connecting bolts 3A for connecting the diagonal member 4 and the like are provided around the cylindrical hole 2a. The screw hole 2c is formed in the solid portion 2b having a sufficient wall thickness left in the spherical joint 2, so that the depth necessary for joining can be secured.

In a three-dimensional truss structure using a spherical joint, when the chord member 1 is placed at a predetermined position on the truss construction site, the diagonal member 4 is interposed between the spherical joints 2 and 2, and the diagonal member 4 is attached to the diagonal member 4. The slanting member 4 is fixed by a fastening operation with a small work load by the joining bolt 3A which is thin enough to match the acting axial force. The spherical joint 2 rarely receives the transmission of the axial force acting on the chord member 1, and therefore, the thickness of the solid portion 2b is selected to the extent necessary for screwing the joining bolt 3A in order to reduce its weight. Thus, the spherical diameter of the spherical joint 2 can be selected as small as possible.

According to the third aspect of the present invention, the large diameter perforated spherical joint 2 is attached to the chord member 1 in the middle portion of the truss structure,
A small diameter perforated spherical joint 2A is used at the end portion. In the spherical joint 2A having the small-diameter cylindrical hole 2e, since the chord member 1A is thinner than the chord member 1 in the middle portion, the spherical joint 2
The solid portion 2f in A is the solid portion 2 of the large diameter perforated spherical joint 2.
It is secured thicker than b. Therefore, its thick solid part 2
It is easy to form a large screw hole 2d in f, and at the end portion of the truss structure, a diagonal member 4 that exerts a relatively large axial force.
A can be fastened with thick joining bolts. By doing so, it is possible to arrange the spherical joints having different wall thicknesses in the solid portion in consideration of the difference in the axial force acting on the chord members 1 and 1A and the diagonal members 4 and 4A. The occurrence of excess and deficiency of strength is eliminated, and the balance of overall yield strength is achieved.

[0018]

According to the present invention, since the chord member is passed through the spherical joint, the axial force acting on the chord member is less likely to reach the spherical joint, and the structure of the spherical joint is simplified. It is easy to reduce the weight. Further, the spherical joint and the diagonal member are bolt-bonded without welding, so that the connection work at the site is simplified and the work efficiency can be improved. A small diameter bolt can be used for the joining.

According to the three-dimensional truss structure in which the members are joined by using the spherical joint, the above-mentioned effects are exhibited, and in constructing the truss structure, the burden on the worker in the fastening work is promoted, and the system is improved. Achieves both high field workability equivalent to a truss and low cost equivalent to a direct welding truss.

If a chord member thinner than the chord member in the middle portion is adopted at the end portion of the truss structure and a large solid portion is left in the spherical joint, a bolt for joining used in the diagonal member in the middle portion. It is possible to form screw holes for thicker bolts. As a result, the diagonal member at the end portion where the axial force tends to increase can be thickened, and the overall strength of the truss structure can be improved.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A spherical joint according to the present invention and a space truss structure joined by members using the same will be described below in detail with reference to the drawings showing the embodiments. FIG. 2 shows a part of a space truss structure in which a long chord member 1 adopted for a large span building is fixed through a spherical joint 2, and a joining device 3 is attached to the spherical joint 2 through which the chord member 1 penetrates. The diagonal member 4 is fixed through the structure.

The chord member 1 is, for example, a thick pipe member having a diameter of 267 mm, and a spherical joint 2 into which the chord member 1 is inserted in advance.
The sphere diameter is, for example, 470 mm. The chord material 1 has an appropriate length that can be transported by a vehicle, and is welded to the construction site at an intermediate position 5 where the spherical joint 2 does not exist, etc., if necessary, to form a long material.

Although the spherical joint 2 is originally a solid sphere, FIG.
As shown in FIG. 3, a cylindrical hole 2a having a diameter that allows the chord member 1 to penetrate therethrough is formed in the center thereof. The spherical joint 2 is manufactured by, for example, hot forging, but the chord member 1
And then welding around the opening of the cylindrical hole 2a.
It is said that the spherical joint 2 is fixed to the chord member 1 at the time of shipment from the factory.

In the spherical joint 2 described above, a screw hole 2c extending from the spherical surface side toward the center of the spherical joint 2 for screwing a bolt is formed in the solid portion 2b around the cylindrical hole 2a. . The diagonal member 4 can be attached to the screw hole 2c by the joining device 3 whose structure will be described below. The cylindrical hole 2a has almost the same diameter as the outer diameter of the chord member 1, but may be bored so as to be slightly expanded as shown by a virtual line except for both ends. In that case, the workability when inserting the chord member 1 into the spherical joint 2 at the factory is improved.

The joining device 3 is a device for joining the diagonal member to the two spherical joints 2 and 2 whose positions are fixed, so that the structure thereof is disclosed in Japanese Examined Patent Publication No. 4-73496 and Japanese Utility Model Publication No. 6-12.
No. 084, No. 2-18003 and No. 2
A joint bolt disclosed in Japanese Patent Publication No. 125102, which is freely movable, is used. As an example thereof, the structure described in Japanese Examined Patent Publication No. 4-73496 is shown in FIG. 1, and the configuration and action will be described below with reference to the drawing.

The joining device 3 includes a joining bolt 3A which is screwed into the screw hole 2c of the spherical joint 2, and the joining bolt 3A.
Sleeve nut 3 that is attached to and supports to move back and forth
B, a sleeve 3C for covering the joining bolt 3A and giving a rotational force, and a coil spring 3D for urging the joining bolt 3A to project it to the outside of the sleeve 3C. The sleeve nut 3B is for attaching the joining device 3 to the end member 4a welded to close the end portion of the diagonal member 4, and is a cylindrical body screwed to the end member 4a. .

The joining bolt 3A has threads formed on both ends,
A right screw 3a screwed into the screw hole 2c of the spherical joint 2 and a left screw 3b for screwing an anchor nut 3E for preventing the joining bolt 3A from falling off the sleeve nut 3B.
Have. A hexagonal boss portion 3d is formed on the right-hand thread 3a side of the shaft body portion 3c therebetween. In the sleeve 3C described above, the sleeve hole 3 having the same sectional shape as the outer shape of the hexagonal boss portion 3d is formed.
The hexagonal surface 3f formed on the outer surface of the sleeve 3C having the e formed therein is rotated by applying a wrench or the like to the joining bolt 3
A can rotate and can be displaced in the sleeve hole 3e.

The coil spring 3D for urging the joining bolt 3A toward the screw hole 2c is arranged so as to surround the shaft body portion 3c between the hexagonal boss portion 3d and the sleeve nut 3B in the sleeve hole 3e. . Therefore, when the joining device 3 is brought into contact with the spherical joint 2, the joining bolt 3A retracts and the coil spring 3D is compressed, and the joining bolt 3A matches the screw hole 2c, like the joining device 3 on the right side of FIG. Then, the urging force acts so as to press the joining bolt 3A toward the screw hole 2c.

According to such a structure, the diagonal member 4 can be joined to the spherical joint 2 penetrating the chord member 1 through the joining device 3 as follows, and the advantage of the system truss system is maximized. It is possible to transmit the axial force of the chord member 1 by the welding method while making the best use of it. First, in a factory, the chord member 1 is inserted into the cylindrical hole 2a of the spherical joint 2, and the welding 6 is applied around the opening of the cylindrical hole 2a. Then, for example, it is transported to a construction site of a space truss plate 9 in which a system truss member 7 indicated by a thin line in FIG. 3A is joined to a spherical node 8 indicated by a small circle. Such a three-dimensional truss plate 9 is supported by a scaffold or the like (not shown), and the chord member 1 is appropriately welded above it at the intermediate position 5 (see FIG. 2) to have a length suitable for the truss structure.

A diagonal member 4 as a system truss member to be joined to the spherical joint 2 is provided with joining devices 3 and 3 at both ends thereof, and the diagonal member 4 is a spherical joint fixed to the chord member 1. 2 and another spherical joint 2 of the other parallel chords 1 or between the spherical joint 2 fixed to the chord 1 and the corresponding spherical node 8 of the space truss plate 9. The position of the spherical joint 2 is determined by the arrangement of the chord members 1 and 1, and the position of the spherical node 8 of the space truss plate 9 is also fixed. At the position, the distance between the spherical joints 2, 2 and the like is the exact size according to the previously designed length. Of course, the length L (see FIG. 1) from the end surface of the sleeve 3C of the joining device 3 at the one end to the end surface of the sleeve of the joining device at the other end is also the same as the above-described regular size by machining.

When arranging the diagonal member 4 in the above-mentioned space, if the joining bolt 3A projects from the end surface of the sleeve 3C even slightly, the interposing work becomes extremely difficult. However, according to the joining device 3 as described above, the protruding joining bolt 3A is brought into contact with the surface of the spherical joint 2 or the surface of the spherical node 8 to retract the coil spring 3D into the sleeve 3C while compressing it. (See the joining device 3 on the right side of FIG. 1). Joining bolt 3A
When the tip of the coil matches the screw hole 2c, the coil spring 3
Due to the restoring force of D, the tip of the right screw 3a fits into the screw hole 2c. The joining bolt 3A is still in a biased state, and when the sleeve 3C is rotated clockwise, the joining bolt 3A also rotates and is screwed into the screw hole 2c. When it rotates to some extent,
Although the coil spring 3D is in a free state, the right screw 3a is already engaged with the screw hole 2c at that time, and the sleeve 3C does not have to be biased by the coil spring 3D.
The rotation of the joining bolt 3A allows the joining bolt 3A to be deeply screwed into the screw hole 2c.

In this way, the diagonal members 4 are joined to the spherical joint 2 and the spherical node 8 one after another. The system truss member 4 is provided between the spherical joint 2 of the chord member 1 and the spherical joint 2 of the other chord member 1.
In the case of interposing, the joining form is as shown in FIG. Of course, as shown in (a) and (b) of FIG. 4, it can also be applied to a keel truss 11 for connecting two warren space trusses 10, 10 on the left and right. In the above description, the space in which the diagonal member 4 is to be inserted corresponds to the length L of the diagonal member 4 and the spherical joints 2 and 2 are in an immovable state. When one of the spherical joints 2 can be slightly displaced depending on the construction procedure of, the coil spring 3D is not provided as a joining device,
Further, it is possible to use a simple structure in which the tip of the right screw 3a always projects from the end surface of the sleeve 3C.

In the truss structure thus assembled, the chord member 1 is in a state of passing vertically through the truss structure,
The axial force acting on the chord member 1 is transmitted in the axial direction without being hindered by the spherical joint 2. Therefore, a large axial force does not act on the spherical joint 2, and the chord member 1 is attached to the spherical joint 2.
It is not necessary to give a proof strength that takes into account the axial force of. That is, normally, it is sufficient to give strength to the diagonal member 4 to which a force smaller than that of the chord member 1 acts, in order to meet the strength. Therefore, the spherical joint 2 has a simple structure as shown in FIG. 1, and the weight can be reduced as much as possible. Conversely speaking, in order to reduce the weight, the thickness of the solid portion 2b is selected so that the strength required for screwing the joining bolt 3A is secured, and the spherical diameter of the spherical joint 2 is made as small as possible. You can also keep it.

By forming the screw hole in the solid portion of the spherical joint in this manner, it is possible to secure a screw hole having a sufficient depth for screwing the joining bolt. The highly practical effect that cannot be obtained with the spherical shell described in the prior art, that is, the spherical joint is deformed or the machining allowance of the screw hole cannot be obtained, is caused by the existence of the solid portion having high rigidity. The effect that can be avoided is exhibited. In the case of a spherical shell, for example, two hollow hemispheres made by pressing a steel plate are welded around the edges to produce a hollow sphere, and then a hole for inserting a chord is formed. However, the spherical joint adopted in the present invention has an advantage that it can be easily formed by a small number of steps by hot forging including formation of a cylindrical hole.

Furthermore, since field welding is not used for joining the system truss members, the welding work requiring skill and time is eliminated in the end, and the joining work is simplified and speeded up. In addition, the bolts used can be thin joint bolts built into the joint device, that is, the thickness can be set to correspond to the axial force acting on the system truss member, and the fastening work is extremely easy, and the labor is also greatly reduced. Planned. As described above, according to the present invention, it is possible to achieve both the high on-site workability of the system truss method and the advantage of the direct welding truss method, and accordingly, to improve the axial force transmission capability of the string material and the excessive strength of the spherical joint. Avoidance and even increased rigidity of the joint in the spherical joint is realized.

By the way, since there is no chord member that penetrates the spherical joint to cut off the space inside the pipe on the way, a prestressing wire or a PC steel rod can be internally provided. Therefore, it becomes possible to introduce the prestressing method, and it becomes possible to impart even higher yield strength to the truss structure having a large span.

FIG. 5 shows an example in which the spherical joint or truss structure according to the present invention is applied when the thickness of the chord member differs on the way. In a truss structure, generally, the axial force of the chord material at the end portion is smaller than that of the chord material at the middle portion. To do. In consideration of this, the reducer 12 may be welded to the end portion (the right end portion in the drawing) of the chord member 1 to connect the middle thick chord member 1A.

In this case, the large diameter perforated spherical joint 2 is used in the middle portion of the truss structure, and the small diameter perforated spherical joint 2A is used in the end portion of the truss structure. That is, the large-diameter perforated spherical joint 2 is formed with a cylindrical hole 2a having a large diameter corresponding to the chord member 1, and the small-diameter perforated spherical joint 2 is formed.
In A, a cylindrical hole 2e having a small diameter and adapted to the chord member 1A is formed. In this small diameter perforated spherical joint 2A, the solid portion 2
Since the wall thickness of f can be ensured to be larger than that in the large diameter perforated spherical joint 2, a large diameter screw hole for attaching the diagonal member 4A thicker than the system truss member 4 at the intermediate portion to the solid portion 2f thereof. 2d can be formed.

As can be seen from the above description, when the spherical joint having the solid portion around the cylindrical hole is used, the thickness of the diagonal member 4 to be joined, that is, the axial force acting on the diagonal member 4. The bolt connection according to the size of is realized, and the highly practical effect which cannot be obtained by the spherical joint made into the spherical shell is exhibited. In addition, in FIG. 5, the spherical diameter of the small-diameter perforated spherical joint 2A is shown to be the same as that of the large-diameter perforated spherical joint 2, but the diagonal member at the end portion of the truss structure need not be particularly thick. In this case, the small diameter perforated spherical joint 2A can be made smaller than the large diameter perforated spherical joint 2. In any case, considering the axial force acting on each member in the truss structure, it is possible to optimize the design of the spherical joint by reducing the weight of the spherical joint. Improvement is achieved.

[Brief description of drawings]

FIG. 1 is a partially enlarged cross-sectional view of a space truss structure to which a spherical joint according to the present invention is applied.

FIG. 2 is a partial assembly view of the space truss structure according to the present invention.

FIG. 3 (a) is a plan view in which a space truss structure adopting the spherical joint according to the present invention is applied to a space truss plate, and FIG. 3 (b).
Is the front view.

FIG. 4A is a plan view of a truss structure when the space truss structure according to the present invention is applied as a keel truss;
(B) is the front view.

FIG. 5 is an assembled partial view of a truss structure in which spherical joints having different thicknesses of a solid portion are used in an intermediate portion and an end portion.

FIG. 6 is a partial front view of a prior art truss structure joined by welding.

FIG. 7 is a partial front view of a truss structure as a prior art in which a chord member is inserted into a spherical shell.

[Explanation of symbols]

1, 1A ... Chord material, 2 ... Spherical joint (large diameter perforated spherical joint),
2A ... Small diameter perforated spherical joint, 2a, 2e ... Cylindrical hole, 2b
... solid part, 2c ... screw hole, 2d ... large diameter screw hole, 2f ... solid part, 3 ... joining device, 3A ... joining bolt, 4, 4A ... diagonal member (system truss member).

Claims (3)

[Claims] 1. A spherical joint that is capable of penetrating and fixing a long chord member used in a large span building to form a space truss, wherein the spherical joint has the chord member at the center of a solid sphere. A cylindrical hole for penetrating is formed, and a solid bolt around the cylindrical hole is screwed with a joining bolt for fixing the diagonal member or the system truss member between the spherical joints by a joining device. A spherical joint for a space truss, wherein a screw hole extending from the spherical side toward the center of the spherical joint is formed. 2. A three-dimensional truss structure in which a long chord member employed in a large span building is fixed through a spherical joint, wherein the spherical joint is for penetrating the chord member in the center of a solid sphere. A cylindrical hole is formed, and a threaded hole extending from the spherical surface side toward the center of the spherical joint for screwing a joining bolt is formed in a solid portion around the cylindrical hole. A spherical member characterized in that a diagonal member or a system truss member is interposed and fixed between the spherical joints by a connecting device for screwing a connecting bolt into the screw hole of the spherical joint that has penetrated the chord member into the hole and is fixed in advance. A three-dimensional truss structure in which members are joined using joints. 3. The three-dimensional truss structure according to claim 2, wherein the intermediate portion of the truss structure has a large-diameter perforated hole in which a large-diameter cylindrical hole is formed to allow a thick chord member to pass therethrough. A spherical joint is used, and at the end portion of the truss structure, a diagonal member or a system truss that is connected to the chord member, penetrates a chord member thinner than the chord member, and is bolted to the large diameter perforated spherical joint. A three-dimensional truss structure in which members are joined using a spherical joint, characterized in that a small-diameter perforated spherical joint in which a large-diameter screw hole to which a member thicker than a member is attached is formed is used.