NEHRP Clearinghouse
- Title
- Probabilistic Site-Dependent Response Spectra.
- File
- PB290353.pdf
- Author(s)
- Kiremidjian, A. S.; Shah, H. C.
- Source
- Banco Central de Nicaragua, Managua.; National Science Foundation, Washington, DC. Applied Science and Research Applications., April 1978, 93 p.
- Identifying Number(s)
- 29
- Abstract
- Effects of local soil conditions on the PGA (Peak Ground Acceleration), the frequency content, and the amplification factor are investigated. Analysis goals are to obtain peak ground motion modification parameters for correcting the probability distributions on the peak ground acceleration values for the site of interest; to develop site dependent response spectral shapes (or dynamic amplification factors) and probability distributions of the latter for three basic soil types; and to develop probability distributions on response spectra at a given location for the three different soil types and from them to obtain design response spectra for a specified risk level. Some significant observations were: (1) Peak ground acceleration from a given earthquake, whose epicenter is within 25 km from the site of interest, diminishes in value by factors of 1.0, 0.75, and 0.60 as the local site conditions change from firm ground to intermediate soils, to alluvial soils; (2) Probability distributions on peak ground acceleration for soil classes 0 and 1 can be derived from the distribution for soil class 2 by applying the soil factors of Ko and Kl; (3) Spectral shapes for the three soil types described by classes 0, 1, and 2 are found to be statistically independent of peak ground acceleration; and (4) The stochastic behavior of dynamic amplification factors is found to be best represented by the gamma distribution.
- Keywords
- Probability distribution functions; Soil classification; Earth movements; Dynamic response; Ground motion; Earthquake engineering; Soil dynamics; Peak ground acceleration; Earthquakes; Soil analysis