THE EFFECT OF SOURCE DEPTH AND LOCAL SITE TO THE ATTENUATION CHARACTERISTICS OF RESPONSE SPECTRA

2010 ◽

Vol 1 (1) ◽

pp. 25-41 ◽

Cited By ~ 1

Author(s):

T. G. Sitharam ◽

K. S. Vipin

Keyword(s):

Seismic Hazard ◽

Peak Ground Acceleration ◽

Site Effects ◽

Response Spectra ◽

Probabilistic Logic ◽

Site Classification ◽

Ground Acceleration ◽

Entire Study ◽

Local Site Effects ◽

Local Site

The local site effects play an important role in the evaluation of seismic hazard. The proper evaluation of the local site effects will help in evaluating the amplification factors for different locations. This article deals with the evaluation of peak ground acceleration and response spectra based on the local site effects for the study area. The seismic hazard analysis was done based on a probabilistic logic tree approach and the peak horizontal acceleration (PHA) values at the bed rock level were evaluated. Different methods of site classification have been reviewed in the present work. The surface level peak ground acceleration (PGA) values were evaluated for the entire study area for four different site classes based on NEHRP site classification. The uniform hazard response spectrum (UHRS) has been developed for the city of Bangalore and the details are presented in this work.

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Effects of Local Site Conditions on Seismic Responses of a Reactor Containment Structure

Volume 8: Seismic Engineering ◽

10.1115/pvp2006-icpvt-11-93527 ◽

2006 ◽

Author(s):

Jian-Chu Chen

Keyword(s):

Shear Wave ◽

Half Space ◽

Wave Velocity ◽

Shear Wave Velocity ◽

Response Spectra ◽

Site Conditions ◽

Pressurized Water ◽

Soil Thickness ◽

Local Site ◽

Local Site Conditions

The effect of local site conditions on soil-structure interaction (SSI) responses of a pressurized water reactor (PWR) containment building founded on different site conditions was investigated using substructure SSI analysis procedure. The structure was analyzed for both surface and embedded foundation conditions for each site with an exception for one half-space site with shear wave velocity 5000 fps. Only the surface foundation was analyzed for this very stiff half-space site. A total of 23 analyses are presented in this paper. Responses including peak ground accelerations and response spectra at selected locations were compared. The results indicate that the local site conditions have a significant influence on SSI response particularly for the structure founded on the surface of shallow soil deposit overlying competent rock. For thick soil sites having shear wave velocity larger than 1000 fps and having soil thickness greater than 3.5 times the radius of the structure, the effect of the soil thickness is not important.

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Evaluation of Peak Ground Acceleration and Response Spectra Considering the Local Site Effects

Geotechnical Applications for Earthquake Engineering ◽

10.4018/978-1-4666-0915-0.ch001 ◽

2012 ◽

pp. 1-17

Author(s):

Sitharam T. G. ◽

Vipin K. S.

Keyword(s):

Seismic Hazard ◽

Peak Ground Acceleration ◽

Site Effects ◽

Response Spectrum ◽

Response Spectra ◽

Site Classification ◽

Ground Acceleration ◽

Local Site Effects ◽

Local Site ◽

Uniform Hazard Response Spectrum

The local site effects play an important role in the evaluation of seismic hazard. The proper evaluation of the local site effects will help in evaluating the amplification factors for different locations. This article deals with the evaluation of peak ground acceleration and response spectra based on the local site effects for the study area. The seismic hazard analysis was done based on a probabilistic logic tree approach and the peak horizontal acceleration (PHA) values at the bed rock level were evaluated. Different methods of site classification have been reviewed in the present work. The surface level peak ground acceleration (PGA) values were evaluated for the entire study area for four different site classes based on NEHRP site classification. The uniform hazard response spectrum (UHRS) has been developed for the city of Bangalore and the details are presented in this work.

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Microtremor analysis of local geological conditions

Bulletin of the Seismological Society of America ◽

10.1785/bssa0660010045 ◽

1976 ◽

Vol 66 (1) ◽

pp. 45-60 ◽

Cited By ~ 1

Author(s):

Lewis J. Katz

Keyword(s):

Transfer Functions ◽

Response Spectra ◽

Earthquake Risk ◽

Time Interval ◽

Time Intervals ◽

Local Site ◽

Power Spectral ◽

Geological Conditions ◽

Long Time ◽

Positive Correlations

abstract The application of microtremor spectra in predicting frequency-dependent amplification effects of local site geology was investigated. Long time-interval (> 45 min) microtremor data were used to estimate Power Spectral Density (PSD) plots. Peaks occurring in these PSD plots were correlated with peaks of transfer functions (Haskell, 1960 and 1962) calculated from known geological models. The resulting apparent positive correlations indicate that a procedure of estimating PSD plots from long time intervals of microtremor data would be useful in predicting response spectra for earthquake risk evaluation.

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