I.M. Mantawy, H. Farhoud
Rowan University,
United States
Keywords: SCBF, seismic, repair, deconstruction, additive manufacturing
Summary:
The use of special concentrically braced frames (SCBFs) in lateral load-resisting systems has increased in the last decades. SCBFs, according to the latest AISC provisions, are designed to provide significant inelastic deformation capacity primarily through tensile yielding and post buckling inelastic deformation which is suitable for seismic regions. Even though SCBFs satisfy design requirement for life safety, they sustain high level of damage primarily buckling which results in economic losses due to the need for replacement. The design and analysis of SCBFs require careful consideration of several factors, including the properties of the materials used, the geometry of the brace and structure, and the expected seismic forces. One advancement in bracing systems is the development of buckling restrained braces which restrict bucking by encasing the steel member with stiff materials (commonly concrete) during the seismic loading. The new concept presented in this paper focuses on concentrating the damage due to tensile yielding and inelastic buckling in a segment of the brace (fuse) while protecting the rest of the bracing members. The SCBFs are repairable after high-level seismic excitation by replacing the damaged fuse. The replaceable fuses, recycled from the damaged fuse, are additively manufactured to achieve desired ductility through optimized geometry. The presentation will include a description of numerical and experimental results from a small-scale specimen tested under cyclic protocol load at Rowan University’s Additive and Robotic Construction Laboratory (ARC-Lab).