Location: Virtual - GoToWebinar
Cost: SEAW Members and Students - FREE!
Non-Members - $15
Register to Attend: Click here. After registering, you will receive a confirmation email containing information about joining the webinar.
Presentation:
Concentrically braced frames (CBFs) have been used as seismic lateral force resisting systems for many years, but current seismic design provisions were not instituted until the about 1995. Hence many older braced frames in seismic regions do not meet current seismic design requirements. The seismic rehabilitation design standard, ASCE 41, is nominally intended to address the seismic performance and retrofit of these older buildings. However, the ASCE 41 provisions for braced frames were developed in early 1990’s, which both preceded development of current AISC 341 for SCBFs and current research on older and retrofitted CBFs. The AISC 342 standard has been approved and is being further updated to replace ASCE 41 provisions for seismic evaluation and retrofit of steel buildings. AISC 342 will update all steel provisions, but it particularly updates provisions for braced frames, since there has been extensive research on the seismic performance of braced frames in the past 20 years. This session will show the background to these AISC 342 braced frame provisions, the changes made in the provisions, the consequences of the changes, and an example application of the new provisions.
Presenter:
Dawn Lehman is a Professor of Civil and Environmental Engineering at the University of Washington. She received her BS from Tufts University in 1989 and her PhD from U.C. Berkeley in 1998. She worked as a structural engineer in Boston MA between these degrees. She has been a faculty member at the University of Washington since 1999. Her research expertise lies in seismic engineering of structural systems. She has conducted research on a range of systems including reinforced concrete walls and frames, steel braced frames, as well as concrete-filled-tube, precast and reinforced-concrete bridge systems. Her research results have been implemented in codes, design manuals and provisional structural engineering recommendations, including AASHTO, AISC, WSDOT BDM, Caltrans SDM, and ASCE 41. She has authored over 100 peer-reviewed research articles. She led the technical investigation of the partial collapse of Champlain Towers South as a consultant to the Miami Herald. The team was awarded the Pulitzer Prize for Breaking News for this work.
