GB2044830A - Latticed constructions - Google Patents

Abstract

A construction module 10 comprises a lower stringer 13, and spaced apart upper stringers 11, 12. Horizontal struts 15 inter-connecting the upper stringers 11, 12, and inclined struts 14 connecting the upper stringers to lower stringer 13, define spaced pyramidal frames with their apices at the stringer 13. An end piece comprising struts 16 and an extension of the lower stringer 13 may be provided. The module is used for making up space frames and roof constructions. <IMAGE>

Description

SPECIFICATION Improvements in space frame constructions This invention relates to improvements in space frame constructions, "space frames" being generally defined as large span lattice constructions distributing stress in at least two directions in plan for use in providing roof or floor structures for buildings where large unobstructured floor areas are desired.

Space frames are usually made to be "modular" or of individual members with special joints so that their components can be factory made, and if modular assembled into prefabricated units, and these units site assembled to form the complete space frame. In all these types of space frames, numerous individual modules or members and joints are used with the result that even the most apparently negligible error in each component can have a cumulative effect which poses serious problems in maintaining the required camber of the frame. In addition, these other methods of constructing space frames are difficult to assemble if strip erection techniques are required due to limited site space.

An object of the invention is therefore to provide a construction element or module which is suitable for use in constructing space frames and which enables some of the problems mentioned to be overcome or minimised.

The invention accordingly provides a construction element or module in the general form of a beam of triangulated lattice construction, having a pair of spaced apart upper longitudinal members, a lower longitudinal member below and between said upper longitudinal members, and a plurality of struts interconnecting said members so as to define a plurality of spaced apart (non-contiguous) skeleton pyramids with their apices supported by said lower longitudinal member.

Such structural elements can be butted together end to end and side to side to form an extensive support structure, and it is found that while the elements are not stackable and thus occupy more transport space, than the known pyramidal elements, their assembly is much quicker when each element is structurally equivalent to a plurality of such known elements.

One or both ends of the element may be formed with a skeletal tetra hedral end piece comprising an extension of the lower longitudinal member and a pair of struts one connecting the end of each upper longitudinal member to the lower longitudinal member to form an apex thereat.

A preferred embodiment of the invention will now be described with reference to the accompanying drawings wherein, Figure 1 shows a persective view of a construction element according to the invention: Figure 2 shows a plurality of such elements joined together side to side to form a structure, Figure 3 is a side view of a roof construction using elements according to the invention, and Figure 4 is a section on line IV-IV of Fig. 3.

Referring first to Fig. 1 of the drawings, a construction element according to the invention is in the form of a latticed beam or girder 10, comprising a pair of parallel spaced apart upper longitudinal members or side stringers 11, 1 2 and a single lower longitudinal member or bottom stringer 1 3.

The side stringers 11, 1 2 are each connected to the bottom stringer 1 3 by diagonal inclined struts 14, and to each other by spaced transverse struts 1 5. The inclined struts 14 and transverse struts 1 5 together define a series of skeletal pyramids with a square base, and with their downwardly directed apices defined by the convergence of struts 14 where they join the bottom stringer 13.

The pyramids are spaced apart by a distance equal to their own base width, as the struts 1 5 divide the space between side stringers 11, 1 2 into a series of open squares.

One end of the beam 10 is formed with a tetrahedral end cone, defined by a pair of sloping struts 1 6 which join the ends of the side stringers 11, and 1 2 to the end 1 7 of the bottom stringer 13, which projects beyond the side stringers.

The joints between struts and stringers are effected by welding for economy in weight and materials.

Instead of one end of the beam 10 being formed with an end cone, the stringers may terminate together for joining to other similar beam sections to form an extended beam for spanning a wide expance.

Fig. 2 shows a plurality of beam sections 1 0a to 1 0e assembled together side by side to form a roof construction.

The sections 1 Oa to 1 0e are joined together by butting their side stringers, and bolting or welding them together. The end cones formed of struts 1 6 form an edge region for the roof, and further sections 10 can be secured to the other ends of sections 1 0a to 1 0e to extend the width of the roof construction. As can be seen in Fig. 2, the sections are located by tie members 1 8 which extend at right angles to and link the bottom stringer 1 3. This produces a grid arrangement of squares superimposed on offset squares, with an interposed diagonal grid formed by the struts 1 4.

As shown in Fig. 2 the sections 10 are assembled in such a way-that an open square in one section is adjacent pyramids in the adjacent sections, and vice versa so that a chess board arrangement of open squares and pyramids is obtained.

This arrangement obtains as efficient stress distribution as a construction assembled from contiguous pyramid elements with a saving in materials obtained by elementing alternate pyramids.

Figs. 3 and 4 illustrate a complete roof construction 20 assembled from elements 10 according to the invention. The example is of a two part roof, one part 20a being lower than the other 20b.

The roof 20 is supported by side walls 21, 22 an end wall 23 and an intermediate wall 24, the front being open as in Fig. 3, for use eg. as a garage or hanger. Any or all of these walls may be solid masonry, or comprises columns with or without infill.

As seen from Fig. 4 a plurality of sections 1 Oal to 1 0a20 are arranged side by side, and further sections 3 Obl to 10b20, and 10cl to 10c20 are joined end to end to them to complete a large span roof 20b.

The lower roof 20a is formed from sections 10dl to 10yes20 and 1Del to 10e20, sections lOci to 10c20, and 10el to 10e20 are as illustrated in Fig. 1 with tetrahedral end cones to form a sloped roof edge. The remainder are without end zones, and the ends of sections lOdl-20 abutt wall 24, while the ends of section 10a1-20 butt a pelmet wall 25, carrying a fascia frame or panel 26.

After this roof frame is assembled, roof cladding can be placed upon it. It can be seen that wide spans can be covered suitable for factories, storage and hangarage, sports and convention centres and large retail or other market developments.

in addition to the Modules a series of bottom ties are provided which are connected to the apexes of the inverted pyramids. These individual bottom ties can be connected to the Modules in such a way as to produce either squares on plan" or "diagonals on plan".

It is therefore possible within this invention to obtain a top chord configuration of squares or rectangles on plan, bottom chord configuration of squares, rectangles or diagonals on plan and an internal lacing configuration of diagonals on plan. Dependent upon characteristics of the "Space Frame" peripheral support, any of the foregoing combinations may be adopted and the Modules manufactured accordingly. When a square or rectangular bottom chord arrangement is thought to be more economical, then the Modules are manufactured with a permanent longitudinal bottom chord and the Modules are despatched as individual Units. If a diagonal bottom chord arrangement is thought to be more economical, then the Modules are manufactured with a temporary longitudinal bottom chord which can be removed and the Modules can then be stacked for despatch.

Fig. 5 is a diagrammatic view of a roof span of a replacement building being constructed, with several spans 101 already erected, on pillars 24 and end beams 22, 27, over an existing stanchions 31 during the erection process for security.

The spans 101 are made up from separate modular units 10 on the ground and then lifted into position as complete spans by a crane 32 at each end of the span.

After the roof has been completed and clad, the existing buildings 29 can be demolished and the walls and interior of the new building fitted out.

Claims (5)

1. A construction element or module in the general form of a beam or triangulated lattice construction, having a pair of spaced apart upper longitudinal members, a lower longitudinal member below and between said longitudinal members, and a plurality of struts interconnecting said member so as to define a plurality of spaced apart skelton pyramids with their apices supported by said lower longitudinal member.

2. An element or module according to claim 1 wherein either or both ends is formed with a skeletal tetrahedral end piece comprising an extension of the lower longitudinal members and a pair of struts one connecting the end of each upper longitudinal member to the lower longitudinal member to form an apex thereat.

3. A space frame las hereinbefore defined) comprising two or more elements or modules according to claims 1 or 2 errected together.

4. A finished construction including a space frame according to claim 3.

5. A construction element or module substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.