These represent one of the more efficient uses of structural materials. Space frames are threedimensional lattice-type structures that span in more than one direction. It is common practice to apply the "space frame" designation to structures that would more accurately be categorized as "space trusses", that is, assemblies of members pin-connected at the joints, or nodes.
In addition to providing great rigidity and inherent redundancy, space frames can span large areas economically, providing exceptional flexibility of usage within the structure by eliminating interior columns. Space frames possess a versatility of shape and form. They can utilize a standard module to generate flat grids, barrel vaults, domes, and free-form shapes.
The most common example of a space truss structure
is the double-layer grid, which consists of top and bottom chord layers connected by web members. Various types of grid orientations can be utilized. Top and bottom chord members can be either parallel or skewed to the edges of the structure, and can be either parallel or skewed to one another.One of the advantages of having top and bottom chords skewed relative to one another is that the top-chord members have shorter lengths, thereby resulting in a more economical design for compressive forces. Also, the longer bottom chords have fewer pieces and connections.
Most space frames are assembled either in-place on a piece-by-piece basis, or in portions on the ground and then lifted into place. In some cases, where construction sequencing permits, the entire space frame can be preassembled on the ground and then lifted into place.