JPH03119232A - Space truss - Google Patents

Abstract

PURPOSE:To increase rigidity as the flat slab of a space truss by arranging tie rods built to each one of upper and lower chords of the space truss formed by connecting square pyramidal truss units so that both upper and lower chords are at right angles with each other in the shape of a plane. CONSTITUTION:Truss units (t) formed by assembling upper chords 1 and diagonals 3 in the shape of a square pyramid are connected continuously in the shape of a plane. The tips of pyramids of the truss units (t) are connected with lower chords 2 in the shape of a grid. After that, upper tie rods 4 are built in the direction of one diagonal of unit grids of the upper chords 1. Then, lower tie rods 5 are built in the direction of one diagonal of grids of the lower chords 2 so that they are at right angles with the upper tie rods 4 in the shape of a plane. Constrained effect of each unit grid is promoted. According to the constitution, the rigidity of a space truss T is increased and, at the same time, a sectional size of a member against the same load can be reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a three-dimensional truss constructed by continuously connecting truss units assembled in the shape of a quadrangular pyramid in two directions.

(Problem to be solved by the invention) A truss unit assembled in a square pyramid shape from four upper chord members and four diagonal members as in Patent No. 410.917, No. 443.434, etc. The upper and lower chord members are arranged continuously, connecting the adjacent upper chord members to each other, and the lower chord members are installed parallel to the upper chord member through the apex of the square pyramid, so that the upper and lower chord members each form a lattice-like network. The three-dimensional truss is
As a general form of truss structure, it has been widely used for roof bridges of large-span structures.

By the way, in this type of space truss, the restraint between the nodes in the diagonal direction of the lattice made up of the upper chord members and the lower chord members is weak, and the torsional rigidity around the diagonal lines is insufficient. If large loads are expected due to factors such as the size of the structure and the shape and weight of the roof, adoption of this truss structure may be abandoned, and you may face the limits of its application. .

This invention was made by paying attention to the above-mentioned structural limitations of the space truss, and aims to propose a new space truss with a high load-bearing capacity.

(Means for Solving the Problems) In the present invention, the rigidity of the lithographic plate is increased by constructing connecting members in the diagonal direction of each lattice between the nodes of the upper chord member and the lower chord member to restrain the unit lattice. By intersecting the directions of the connecting members of the upper and lower chord members, we eliminate the directionality of rigidity, and at the same time distribute the force throughout the entire body, reducing the stress borne by the truss members and expanding the scope of application of the zero truss structure. Expand.

A three-dimensional truss consists of a truss unit assembled in a quadrangular pyramid shape from top chord members and diagonal members, arranged continuously in two directions, connecting the axially adjacent top chords to make them continuous, and The lower chord is connected between the nodes located in parallel to the upper chord, and each of the upper and lower chords forms a lattice-like mesh. An upper tie member and a lower tie member are installed in one diagonal direction, respectively.

The upper tether material and the lower tether material are constructed in a direction that intersects with each other in a plane.

(Example) The present invention will be explained below based on the drawings showing one embodiment.

As shown in FIG. 1, the three-dimensional truss T of the present invention is configured in a two-dimensional lattice shape by continuously connecting truss units t assembled in the shape of a quadrangular pyramid in advance in two directions. The upper connecting material 4 is a horizontal place of a unit grid between the nodes of the lower chord material 2 and the nodes of the lower chord material 2. The ability to maintain the shape of the lattice is enhanced by installing lower connecting members 5 respectively.

The truss unit t is the basic unit of the three-dimensional truss T, and as shown in Fig. 3, it consists of four upper chord members 1 and four diagonal members 3.
Each member is connected to a ball joint 6 that serves as a node of the three-dimensional truss T.
The zero-ball joint 6, which is assembled by connecting to the upper chord member 1, is connected to the position where the upper chord member 1 and the diagonal member 3 come together, and to the position where the diagonal members 3 come together.

For example, as shown in FIG. 1, these truss units are continuously arranged in a plane at every other square with their apexes facing downward.

And the truss unit 1 adjacent to the upper chord member 1 in the axial direction.
By connecting the upper chord members 1, 1 of 1 to each other and making them continuous, Fig. 2-! As shown in the figure, the upper chord material 1 forms a mesh having continuous unit cells.

In the part surrounded by the truss unit t placed one square, the upper chord 1 of the surrounding truss unit t also serves as the upper chord 1 of the adjacent lattice, so at the site, the diagonal member 3 is connected to the upper chord 1. The diagonals 3.3 are connected to each other.

In addition, a lower chord member 2 is installed parallel to the upper chord member 1 between the nodes at the apex position of the square pyramid, and the lower chord member 2 is also used as shown in Fig. 2-■,■.
A lattice-like mesh is formed as shown in . The broken line in ■ and the solid line in ■ indicate the lower chord material 2.

At this time, since the diagonal members 3 and the lower chord members 2 of the adjacent 4IiIl truss units t form a truss unit t with the apex facing upward, the main body truss T is first
After arranging the truss unit t with its apex facing upward,
You can also assemble it.

As shown in FIGS. 1 and 2, between the nodes of the unit grid of each mesh of the upper chord material 1 and the lower chord material 2, there is an upper connecting material 4
．． A lower tie member 5 is installed.

As shown in the figure, the upper connecting member 4 is installed in the diagonal direction of the unit grid of the upper chord member 1, and the lower connecting member 5 on the other hand is installed in the direction of one diagonal line of the unit grid of the upper chord member 1.
The unit grid is constructed in a direction perpendicular or oblique to the upper connecting member 4.

In FIG. 2, the thick line in ``■'' shows the installed state of the upper connecting material 4, and the thick line in ``■'' shows the installed condition of the lower connecting material 5.

The upper connecting material 4 and the lower connecting material 5 strengthen the restraint of the lattice formed by the upper chord material 1 and the lattice formed by the lower chord material, and the two connecting materials 4 and 5 intersect in a plane to prevent external forces. The flow is dispersed in these two directions, and the stress in the member is equalized over the entire surface.

The upper tether material 4 and the lower tether material 5 are inserted into the entire mesh or partially, and the manner in which they are inserted is determined by the stress of the members.

(Effects of the Invention) The present invention is as described above, and since the upper and lower tie members are constructed in a diagonal direction of the lattice formed by the upper chord members and the lower chord members, respectively, in a state that they cross each other, each The restraining effect of the unit cell increases, and the rigidity of the flat plate increases, and at the same time, the force is dispersed throughout and the stress borne by the truss member is reduced.

As a result, the load-bearing capacity of the three-dimensional truss is increased, the range of application of the three-dimensional truss can be expanded, and conversely, the cross-sectional dimension of the truss member can be reduced for the same load.

[Brief explanation of drawings]

Figure 1 is a perspective view showing an example of assembly of the present invention, Figure 2-
! , ■ are plan views of the upper chord surface and lower chord surface, respectively, and FIG. 3 is a perspective view showing the truss unit. T... Three-dimensional truss, T... Truss unit, 1... Upper chord member, 2... Lower chord member,
3... diagonal material, 4... top tie material, 5.
...Bottom joint material, 6...Ball joint.

Claims (1)

[Claims] (1) A truss unit assembled in the shape of a square pyramid from top chord members and diagonal members is arranged continuously in two directions, connecting the axially adjacent top chord members to make them continuous, and In a three-dimensional truss constructed by connecting the lower chord parallel to the upper chord between nodes located at , and forming a lattice-like mesh between the upper and lower chords, a unit cell is connected between the nodes of the upper chord. A three-dimensional truss characterized in that an upper tie member is erected in a diagonal direction, and a lower tie member is erected between the nodes of the lower chord members in a direction that intersects the upper tie member in a plane.