Modified braces for CBF
This system refers to brace elements of concentric braced frames with reduced cross sections. The reduction in cross section is effected by cutting part of the web and/or part of the flanges and is introduced either near the brace ends (Fig. 6a) or at mid-span of the braces (Fig. 6b). The crosssection reduction enables the designer to fine-tune the system according to current requirements of EN 1998-1, part 6. Using the RBS, the tension bearing capacity of the diagonal may be reduced with smaller influence on the member slenderness. In that way, satisfaction of the controversial code requirements for restricting brace slenderness can be achieved,providing homogeneous plasticization of all braces within the storeys. The modified braces were developed and experimentally/analytically studied by UACEG Sofia during a national Bulgarian research project [17, 18].