... strength of the brace as determined above.FyFyφ φλ © 2000 by CRC Press LLC 39 Seismic Design of Steel Bridges 39.1 Introduction Seismic Performance Criteria • The R Factor Design ... Ductile seismic retrofit of steel deck-truss bridges. ΙΙ: design appli-cations, J. Struct. Eng. ASCE, 124 (11), 1263–1271,1998. 56. Sarraf, M. and Bruneau, M., Ductile seismic retrofit of steel ... earthquake. OCBFs are designed to higher levels of design seismic forces to minimizethe extent of inelastic deformations. However, if an earthquake greater than that considered for design occurs, structures...