The Earthquake Engineering Online Archive

Behavior of peak values and spectral ordinates of near-source strong ground motion over the SMART 1 array

Niazi, Mansour

UCB/EERC-90/17, Earthquake Engineering Research Center, University of California, Berkeley, 1990-06, 118 pages (425.3/N52/1990)

This report uses recordings from the large-scale array of digital accelerometers in Taiwan, called SMART-1, to investigate several important properties of seismic ground motions. The study focuses on the variability of peak vertical and horizontal accelerations, velocities, and displacements. Statistical treatment of this variability is feasible when ground motions are recorded at a group of stations within a limited distance. The three rings of the SMART-1 array have radii of 200 m, 1 km, and 2 km. Since it became operational in September 1980, it has recorded accelerations up to 0.33 g and 0.34 g on the horizontal and vertical components, respectively. At present, there are over 3,000 accelerograms from 53 local earthquakes available. Twelve earthquakes are selected from this group of data, providing more than 700 accelerograms for analysis and statistical treatment. Nonlinear regression procedures are used to fit the peak values to an attenuation form which has as parameters earthquake magnitude and source-to-site distance. In addition, the report includes spectral information on ground motion; correlations are made between spectral ordinate values at 23 discrete frequencies in the range of engineering interest.

Available online: http://nisee.berkeley.edu/documents/EERC/EERC-90-17.pdf (4 MB)