Long span construction

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Structures like aircraft hangers, coliseums, or atriums, that require greater open areas between columnar supports than standard wood or steel structural members can span, are built with long span construction technology. Many designs have been used successfully depending on the area to be spanned, the anticipated roof loads, occupancy use, etc. This lesson will cover only bar joists, trusses, space frames, and folded shell structures.
Bar joists
Bar joists are simply long floor or ceiling truss joists. They usually span from girder to girder, which themselves are supported by widely spaced columns or bearing walls. Prefabricated bar joists are available that are designed for specific load requirements.

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