ENERGY DISSIPATION OF ECCENTRICALLY-BRACED-FRAME (EBF) WITH DIFFERENT LEVEL OF ECCENTRICITY

Abstract

ABSTRACT
This research aimed at eliciting the form of relation that exists between level of
eccentricity (e/L) and energy dissipation (Ed) of an Eccentrically Braced Frame (EBF).
It continued a previous research that studied relative stiffness of an EBF. Three sets of
EBF specimen were analysed by the merit of SAP2000 v9.0.1 computer-software to
obtain range of inelastic drifts and its corresponding range of lateral loads. Specimens
vary in level of eccentricity (e/L) and bay to height ration (h/L). Prior to it, a formula
that calculates energy dissipation of a lateral resistant structure as product of lateral
loads and the corresponding drifts was developed and used throughout the research for
the purpose of quantifying Ed. Each specimen was alternatively loaded in direction
confronting and concurring the bracing component. It was found that there was no
significant difference in the form of relation between e/L and Ed, when lateral load
applied confronting bracing component from when the same load applied concurring
bracing component. Forms of each graph that relates e/L to Ed was presented and
shown to consists of two parts, divided at e/L = 0.2; suggesting that e/L = 0.2 might be
the point where level of eccentricity and relative stiffness of an EBF reach optimum.
Mathematical equations for the relation between e/L and Ed of an EBF were then
developed. In spite of this, an inconsistency with the prevalent theory was observed,
hence the relations between e/L and Ed concluded so far were contested until further
researches be made for clarification.