Estimation of peak relative velocity and peak absolute
acceleration of linear SDOF systems
Jianwei Song, Yi-Lun Chu, Zach Liang and George
C. Lee
Department of Civil, Structural and Environmental Engineering, University at
Buffalo, State University of New York, USA
Abstract: In the
seismic analysis and design of structures, the true velocity and absolute
acceleration are usually approximated by their corresponding pseudo-values. This
approach is simple and works well for structures with small damping (say, less
than 15%). When the damping of a structure is enhanced for the purpose of
response reduction, it may result in large analysis and design errors. Based on
theory of random vibration and the established mechanism of seismic response
spectra analysis, a method is developed (1) to predict the relative velocity
spectra with any damping ratio level directly from the 5% standard
pseudo-acceleration spectrum; and (2) to estimate the peak absolute
acceleration. The accuracy of both is validated by using two selected ensembles
of ground motion records.
Keywords:
damping device; velocity spectrum; absolute acceleration spectrum;
response spectrum analysis
