Input Energy Spectra for Pulse-Like Ground Motions

Abstract

In energy based seismic design (EBSD) approach, effect of ground motions on structures is considered as an energy input to structures (EI). The usage of energy spectra is an effective tool in energy based seismic design (EBSD) methods, such as the use of design acceleration spectra in force-based and displacement-based methods. The obtention of input energy spectra offers an important advantage to determine the energy input to structures with the effect of ground motions. On the other side, near-fault seismic ground motions are frequently characterized by intense velocity and displacement pulses of relatively long periods that clearly distinguish them from typical far-field ground motions. Intense velocity pulse motions can affect adversely the seismic performance of structures. Based on these ideas, a correlation between the impulsivity level and input energy spectrum is presented in this study, and a new parameter is established for evaluating the input energy power. This correlation may aid to select ground motion for structural analysis in near-fault regions.