Investigation on column strengths in steel unbraced frames laterally restrained by elastomeric bearings using the AISC code

Omar, Omar Issa
The restraint provided by elastomeric bearings to frames is rarely taken into account in frame stability design. If taken into account, then the consideration that the restraint they introduce might influence sway condition of the frame makes it harder to classify the frame as braced or unbraced .Conventional methods of stability analysis, e. g the Effective Length Method(ELM), which relies on such a classification, can not be readily applied in its analysis, and advanced or more general methods such as the Direct Analysis Method (DAM) will be necessary, unless the sway condition is assumed by some judgement. In this thesis, these later methods are not considered, and the objective is to study methods that are simple to use in design offices. The approach is therefore to scan codes and specifications for latest developments in frame stability design, in the context of ELM. For this purpose, code provisions in the latest AISC specification(ANSI/AISC 360-2010) and recommendations in Structural Stability Research Council’s guide(SSRC-2010) have been selected. Sway index B2, bracing design provisions and possible use of commercial software for determination of K-factors are investigated. In the investigation, a realistic set of frames, with features of frames in a building likely to be equipped with such bearings, have been selected and analysed. This study focuses on potential methods and means that are available to a designer and not on economy of design or variations in framing configurations, and is therefore not comparative.


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Citation Formats
O. I. Omar, “Investigation on column strengths in steel unbraced frames laterally restrained by elastomeric bearings using the AISC code,” M.S. - Master of Science, Middle East Technical University, 2013.