Assessment of reduced beam section (RBS) moment connections subjected to cyclic loading

Abstract

The disastrous results of the “1994 Northridge” and the “1995 Kobe” earthquakes have shown that there was a poor level of seismic response in moment resisting frame buildings. These buildings were found to have developed limited ductility level, leading to brittle collapse. Extensive scientific research took place studying new design methods for steel connections, providing the acceptable post-elastic behavior for the steel joints and subsequently the desirable seismic response for the post-Northridge/Kobe steel structures.Reduced Beam Section (RBS) moment resisting connections are among the most economical and practical rigid steel connections that were developed, aiming to satisfy the above mentioned target. Although the RBS connection effectiveness was widely investigated using US design and construction practices, research data from European research exists only in the last decade. Recommendations of RBS applications in steel frames were prescribed in EC8, Part3, however the reliability of these recommendations is under consideration.This paper presents the experimental results of two specimens, where the RBS technique was applied. The extended endplate moment beam to column connection (widely applicable in European practices) is used under cyclic loading, and Finite Element Analysis was conducted in order to provide a safe assessment for the RBS application in European steel profiles.