Braced frames, including those that are to resist seismic or large wind loads, traditionally have been analyzed and designed as simple trusses with all joints pinned. However, braced frames using gusset plates are actually braced moment frames (Richard, 1986) because the presence of a typical gusset plate creates a joint zone even larger and more complicated than that of a moment frame connection (Walters et al., 2004). Full-scale tests of braced frames designed to resist seismic loads (Mahin et al., 2002) showed that the structural elements surrounding the braces created a moment frame that was the defacto "primary" lateral force-resisting element rather than the brace(s).

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