Response spectrum - WikipediaRichmond, California U. Newmark andW. Newmark and William J. Hall Published by The Earthquake Engineering Research Institute, whose objectives are the advancement of the science and prac- tice of earthquake engineering and the solution of na- tional earthquake engineering problems. The publication of this monograph was supported by a grant from the National Science Foundation.
Ground motion selection for seismic response analysis - Karim Tarbali
Earthquake Engineering and Engineering Vibration. Newmark design spectra have been implemented in many building codes, especially in building codes for critical structures. Previous studies show that Newmark design spectra exhibit lower amplitudes at high frequencies and larger amplitudes at low frequencies in comparison with spectra developed by statistical methods. To resolve this problem, this study considers three suites of ground motions recorded at three types of sites. Using these ground motions, influences of the shear-wave velocity, earthquake magnitudes, source-to-site distances on the ratios of ground motion parameters are studied, and spectrum amplification factors are statistically calculated. Spectral bounds for combinations of three site categories and two cases of earthquake magnitudes are estimated.
A response spectrum is a plot of the peak or steady-state response displacement, velocity or acceleration of a series of oscillators of varying natural frequency , that are forced into motion by the same base vibration or shock. The resulting plot can then be used to pick off the response of any linear system, given its natural frequency of oscillation. One such use is in assessing the peak response of buildings to earthquakes. The science of strong ground motion may use some values from the ground response spectrum calculated from recordings of surface ground motion from seismographs for correlation with seismic damage. If the input used in calculating a response spectrum is steady-state periodic, then the steady-state result is recorded. Damping must be present, or else the response will be infinite.
Bijan Mohraz; A study of earthquake response spectra for different geological conditions. Bulletin of the Seismological Society of America ; 66 3 : — The current earthquake design spectra are based mainly on response spectra from recording stations located on alluvium deposits. A limited number of studies have shown that shape and the magnitude of response spectra for stations located on rock deposits are different from those located on alluvium deposits. This study examines the effects of geological conditions on the response spectra and the ground-motion parameters such as peak ground acceleration, velocity, and displacement. Design spectra are presented for various sites such as alluvium deposits, rock deposits, and alluvium layers underlain by rock deposits.