Proposed Limits of Stiffener Spacing Requirements for EBF Links Within the Framework of Eurocode 8

Design specifications for Eccentrically Braced Frames (EBFs) provided by both the current AISC and Eurocode (EC) 8 seismic provisions are primarily based on physical tests conducted in the early 1980s. The tests investigated the behavior of, mostly short, EBF links that featured an ASTM A36 steel grade (i.e., nominal 𝑓 = 250 MPa). This paper first ! presents a thorough review of the EC8 stiffener spacing requirements. Finally, we propose new stiffener spacing requirements for short and intermediate length links by formulating and solving analytically the classic plastic plate buckling problem of idealized EBF web plates. The proposed limits are validated via continuum finite element studies. A summary of these studies is presented.