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Prediction of Seismic Design Response Spectra Using Ground Characteristics.
Malushte, S. R.; Singh, M. P.
National Science Foundation, Washington, DC., September 1987, 328 p.
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For seismic design of structures, earthquake input is usually defined in terms of pseudo acceleration response spectra. However, recent research has identified the need of defining the design input in terms of the relative velocity and relative acceleration response spectra as well. Furthermore, for the equivalent linear analysis of hystertically behaving structures, one also needs to define the response spectra of a massless oscillator. Based on the analysis of available earthquake records, the study defines the above mentioned response spectra as the seismic design input for various site conditions. The available earthquake records are classified into five groups according to their site stiffness and epicentral distance as the grouping parameters. The motion parameters of average frequency and significant duration are obtained for each group and their effect on the response spectra is studied. Correlation analyses between various ground motion characteristics such as peak displacement, velocity, acceleration and root mean square acceleration are also carried out for each group. It is shown that the relative spectra can be reliably estimated from the pseudo spectra. The site dependent design spectra are defined for a wide range of oscillator periods and damping ratios.
; Predictions; Seismic reflection method; Statistical analysis; Seismic waves; Spectras; Tables (Data); Earthquake resistant structures; Earth movements; Graphs (Charts); Velocity measurements; Acceleration (Physics); Earthquakes