NEHRP Clearinghouse
- Title
- Preliminary Report on the SMART (Strong Motion Array in Taiwan) 1.
- File
- PB83159400.pdf
- Author(s)
- Bolt, B. A.; Loh, C. H.; Penzien, J.; Tsai, Y. B.; Yeh, Y. T.
- Source
- National Science Foundation, Washington, DC., August 1982, 216 p.
- Identifying Number(s)
- UCB/EERC-82/13
- Abstract
- The first large digital array, called SMART 1 (with radius 2 km and 37 accelerometers), to record substantial ground motion (up to 0.24g horizontal acceleration) became operational in September 1980 in a highly seismic region of Taiwan. During the first year of operation, SMART 1 recorded fifteen earthquakes with local magnitudes ranging from 3.4 to 6.9. Installational and operational details and likely errors in the data processing are presented. For this major preliminary study, recorded wave forms across the array were analyzed for two earthquakes. The correlation coefficient between the acceleration wave forms of the same component recorded at any two array sites was studied. Representative measurements were made of seismic wave coherency, Fourier wave number, and response spectra. Comparisons of power spectra as a function of wave number, frequency, azimuth of propagation, and wave type were made. The engineering analysis included transformations to principal axes, development of generalized response spectrum ratios for characterizing multi-support excitations, and moving window analysis in the time and frequency domains for studying spectral variations of recorded ground motions. The dynamic properties of site conditions and spatial correlations of earthquake motions were studied. A technique using the principal variance ratio was developed to identify the wave direction and type of waves.
- Keywords
- Seismic waves; Correlation techniques; Seismic arrays; Data acquisition; Dynamic response; Ground motion; Earthquake engineering; Power spectra; Taiwan; Earthquakes; SMART 1 seismic array