Systems and methods for fabrication and use of brace designs for braced frames

Abstract

Embodiments of the present invention relate to a structural frame member which includes a brace member that is used to absorb energy when the structural frame is subjected to loadings such as seismic, wind and gravity loads. The brace member is coupled to a restraining member that increases the buckling capacity of the brace member so that the brace member has approximately the same load axial capacity in compression as in tension. Embodiments of the invention also relate to the design, construction and assembly of the connection of the brace member that couples the brace member to a gusset plate which is coupled to the beam and column in the structural frame.

What is claimed is: 
     
         1 . A structural brace member comprising:
 a tubular element having a rectangular cross section;   a core element disposed within the tubular element, wherein no substantial material is disposed within the tubular element between the tubular element and the core element, and wherein the core element comprises:   a horizontal plate; and   two vertical plates, each joined to opposite sides of the horizontal plate to form a cruciform cross-section core element; and   a gusset plate connection assembly comprising:
 a gusset plate coplanar with the horizontal plate; and 
 four connection plates, wherein:
 each connection plate is bolted to the horizontal plate and the gusset plate; and 
 each connection plate is welded to one side of one vertical plate.