Some Considerations on the Inelastic Energy Absorption Factors with Observer Earthquake Motions in Japan

Abstract

Some topics on the earthquake demand reduction to mechanical components due to inelastic energy absorption are discussed analytically with one-degree-of- freedom bilinear model response under the relatively small ductility factor region. Comparing with usual building structures, mechanical components tend to have higher natural frequencies and lower damping values in seismic design practices in Japan, therefore, so-called “Inelastic Energy Absorption Factor” tries to be analyzed with elastic damping factors of 0.02 and 0.05, and with natural frequencies ranged from 1 to 30 Hz, assuming more than fifty strong earthquake motions recorded in Japan as inputs. Finally, the U.S. seismic design practice for mechanical components considering in inelastic energy absorption effects can be reasonably applied to those in Japan, with some notes on the application of “property of energy conservation” rule in the relatively higher frequency region, because it may estimate overly the demand reduction effects under those conditions.