RELATIONSHIP BETWEEN CHARACTERISTICS OF EARTHQUAKE GROUND MOTION AND ASYMMETRY OF STRUCTURAL RESPONSE

Abstract

In this study, relationship between characteristics of earthquake ground motions and asymmetry of structural response are discussed. First, the demand one-side yield seismic coefficient spectrum and the both sides spectrum are newly defined. Second, the ratios of both-sides spectrum to one-side spectrum are calculated by using many observed records. The asymmetry in displacements can be evaluated quantitatively by using spectrum ratio. Consequently, it is clarified that deformation of structures tend to become asymmetrical as natural periods become longer, or distance to the hypocenter is smaller. It is also found that dynamic behaviors of structures are independent from the types of the fault, such as inland active fault or inter plate.