Lessons Learned from Steel Braced Buildings Damaged by the Bam Earthquake of 26 December 2003

Every earthquake provides new lessons for the earthquake engineering profession. The widespread damage to welded connections in steel structures was one of the major overall lessons of the Bam earthquake of December 26, 2003. The brittle nature of the fractures detected in weakly welded steel bracing connections, essentially invalidated the design approaches and code provisions based on «ductile» structural response. This paper reviews the performance of steel braced buildings during the Bam earthquake and the implications for design practice. The results can be used to develop and verify reliable and cost-effective methods for the inspection, evaluation, repair, and rehabilitation of similar existing steel buildings.