JPH0222822B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method of constructing a roof frame, and in particular to a method of constructing a space frame dome using beams and cables.

Conventional technology Traditionally, as roof structures with large spans, (1) reinforced concrete shell structures, (2) steel space frames such as lamellas and geodesic domes, (3) air membrane structures, and (4) cable suspension structures have generally been used. However, prior art to this invention is U.S. Patent No.
There is number 4052334. That is, (5) there is a roof structure in which a tube serving as a compression member is used as the upper chord member and a cable serving as a tension member is used as the lower chord member to curve upward with a beam frame in one direction.

Problems to be Solved by the Invention In the above-mentioned conventional technology, (1) is made of reinforced concrete, which is heavy and requires temporary materials such as temporary frames, supports, and scaffolding, resulting in a long construction period and high cost. (2) requires temporary materials such as scaffolding and is troublesome to assemble, and (3) has the advantage of being lightweight and requiring a short construction period, but requires constant ventilation and maintenance. Management is complicated, and although (4) can be made into a long span, it has the disadvantage that the finishing material that forms the roof surface is subject to deformation, and (5) is a one-way beam structure, so it is rectangular. However, it was not possible to construct a dome-shaped roof structure.

The present invention aims to provide a method for constructing a dome using beams and cables, which does not have these disadvantages and is lightweight, does not require temporary materials, and is economically constructed with a highly workable space frame dome using a rational member structure. That is.

Means for Solving the Problems The means of the present invention for solving the above problems is a method of constructing a space frame dome using beams and cables, in which the top chord is a steel beam and the bottom chord is a steel beam. The material is a cable, and the web material is a steel bundle, and the steel beam is fixed radially around the central axis.The outer end of the cable is fixed to the tip of the steel beam, and the middle part is passed through the lower end of the steel beam. The space frame is installed movably and assembled into a flat surface, and the inner ends of the cables are gathered around the central axis and pulled toward the center, which applies compressive force and bending moment to the steel beam, causing it to curve into a dome shape. , when the cable reaches a predetermined curved surface, the inner end of the cable is fixed to the central axis, and the intermediate part thereof is fixed to the lower end of the steel bundle.

Embodiment An embodiment of the present invention will be described with reference to the drawings.

Reference numeral 1 designates steel beams that serve as upper chord members of the space frame, and as shown in FIG. 4, they are arranged radially around the central axis 2 and fixed to the central axis 2, respectively. 3
is a cable that becomes the lower chord member, and is movably inserted into the support fitting 5 (Figs. 6 and 7) at the lower end of the steel beam bundle 4, which becomes the web material, and is installed at a suitable location in the middle of the steel beam 1. The outer end 6 is fixed to the tip 7 of the steel beam 1 as shown in FIG. 8, and the inner end thereof is pulled out downward through a hole 8 below the central axis 2. It is placed on the ground or in a position close to the roof eaves so that it is in the above state, that is, the state shown in FIGS. 1 and 4, and the foundation assembly is completed at that position.

Next, the cable 3 inserted into the hole 8 of the central shaft 2
When tension is introduced by pulling the cable, the cable is tensioned in a straight line as shown in Figure 2, and compressive force and bending moment act on the steel beam 1, causing it to curve slightly and rise. Next, by erecting a scaffold (not shown) below the central axis 2 or suspending a work basket, the cable 3 is further pulled, resulting in a curved surface as shown in Figure 3, so that a predetermined curved surface is reached. Then, the inner end of the cable 3 is placed on the scaffold or the work basket so that the central axis 2 is aligned as shown in FIG.
The curved surface of the dome is completed by fixing it in the hole 8 with a wedge 9, and fixing the intermediate part to the support metal fitting 5 at the lower end of the steel bundle 4 using a mobile vehicle for high-altitude work or the like.

Effects of the Invention This invention has the most rational member structure in terms of mechanics by subjecting the upper chord member to compression and bending, and the lower chord member to subjecting it to tension, so it can be designed at low cost, and there are no unnecessary members. It has a simple structure and is extremely easy to construct. Since the assembly can be done close to the ground, accuracy is high, and the dome is assembled all at once by gathering each cable to the central axis and pulling it, and there is no need to pull each cable at the tip of each beam, making construction easy. can be,
The curved surface of the dome can be completed in a short period of time without requiring temporary materials such as large-scale scaffolding to support the entire dome.

[Brief explanation of drawings]

The drawings show one embodiment of the invention.
Figures 1 to 3 are explanatory diagrams of only one span seen from the front. Figure 1 shows the state when the ground assembly is completed, and Figure 2 shows the state where the steel beam is slightly curved due to the cable being pulled.
Figure 3 shows the completed dome curved surface, and Figure 4 shows the completed dome surface.
Showing the same state as the figure, the right half is a plan view, the left half is a bottom view showing the cable and steel bundle, Fig. 5 is an enlarged cutaway front view of the central axis, Fig. 6 is an enlarged side view showing the installation of the support fittings, FIG. 7 is a front view, and FIG. 8 is an enlarged front view showing the tip of the steel beam. 1... Steel beam, 2... Central axis, 3... Cable, 4... Steel bundle, 6... Outer end, 7... Tip.

Claims (1)

[Claims] 1 Upper chord is steel beam 1, lower chord is cable 3
The web material is composed of a steel beam bundle 4, the steel beam 1 is fixed radially to the central axis 2, the outer end 6 of the cable 3 is fixed to the tip 7 of the steel beam 1, and the intermediate part is fixed to the steel beam bundle 4. is movably attached through the lower end of the space frame, the space frame is assembled into a flat base, and the inner ends of the cables 3 are gathered around the central axis 2 and pulled toward the center, thereby applying compressive force and bending moment to the steel beam 1. Construction of a dome using beams and cables, which are curved into a dome shape, and when a predetermined curved surface is reached, the inner end of the cable 3 is fixed to the central axis 2, and the middle part thereof is fixed to the lower end of the steel bundle 4. Law.