STRUCTURAL GLASS FACADES - USC School of Architecture

Typical deflection criteria
Deflection criteria vary among the systems; rules of thumb will be provided.
Pre-tension requirements
Open systems as discussed above require prestress forces to achieve stability. This
complicates the design process sometimes requiring the involvement of a specialist. Such
structures also require pre-tensioning in the field to achieve the prestress requirements,
which can complicate the field work, especially depending upon the magnitude of the
prestress loads. This criterion is generally not an issue with closed systems.
Reaction Loads
A number of factors influence the way these structural systems load the anchoring structural
system. The open systems in particular can result in significant reaction loading that must be
understood and identified to the building engineer early in the design process. The relative
differences between the systems will be identified.
The open systems typically apply high reaction forces to the anchoring systems because of
the prestress forces required to stabilize these systems. Such reaction forces, or close
approximations thereof, must be identified early on the to the building engineer responsible
for the anchoring structure. These reaction loads require special consideration because they
are applied continuously, not intermittently like ordinary design loads.
Structural Efficiency (strength to weight)
Many of the structure types identified herein qualify as lightweight building systems.
Structures designed using these systems can be half the weight of conventional systems,
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