The Effects of Near and Far Fault Accelerograms Modification on Seismic Behaviour of Concentrated Braced Steel Frames

Abstract

Steel braces hasve a growing application in building structural and industrial constructions. In the recent years there has been a lot of research done about performance and behavior of these types of structures in elastic and plastic states whos outcomes have been effective on improvement of design criteria and implementation quality of structures. On the other hand since near fault seisms have different properties from those of far fault seisms and issues related to effects of near and far fault have been recently separated in different regulations, seismic behavior of steel constructions designed on the basis of lateral load resisting concentrated bracing system and regulation of designing resisting constructions to seism (Standard No. 800-3rd edition) has been studied in this research. Frames studied are of 5, 10 and 15-floor structues from which one frame has been selected to be studied and time history non-linear dynamic analysis method and effects of two types of near and far fault accelerogram have been used. Values of displacement and floors reverse anchor and base shear in both modified (with scale) and unmodified (without scale) states of near and far fault accelerograms were calculated and the results were compared.