Site-Dependent Spectra Derived from Ground Motion Records in Turkey

2004 ◽  
Vol 20 (4) ◽  
pp. 1111-1138 ◽  
Author(s):  
Erol Kalkan ◽  
Polat Gülkan
Keyword(s):  
Ground Motion ◽  
Seismic Region ◽  
Data Set ◽  
Design Spectra ◽  
Attenuation Relationships ◽  
Scenario Earthquakes ◽  
Geological Conditions ◽  
Ground Motion Records ◽  
Strong Ground ◽  
Spectral Shapes

The current spectral shapes in the Turkish Seismic Code ( TSC) are based on broadly described geological conditions, ignoring fault distance or magnitude dependencies on spectral ordinates. To address this deficiency, a data set created from a suite of 112 strong ground motion records from 57 earthquakes that occurred between 1976 and 2003 has been used to develop horizontal attenuation relationships for Turkey. This way it is possible to construct hazard-consistent design spectra for any national seismic region. The results are compared with the site-dependent spectral shapes of the Uniform Building Code ( UBC) and the current TSC. It is shown that corner periods are consistent with those of UBC. TSC yields wider constant spectral acceleration plateau. Design spectra in both of these documents are conservative if the ground motion library that we used in deriving the spectral shapes is taken as representative. The results of this study enable site-distance–magnitude-specific design spectra suitable as a tool both for deterministic (scenario earthquakes) and probabilistic seismic hazard assessments.

Empirical Attenuation Equations for Vertical Ground Motion in Turkey

2004 ◽  
Vol 20 (3) ◽  
pp. 853-882 ◽  
Author(s):  
Erol Kalkan ◽  
Polat Gülkan
Keyword(s):  
Ground Motion ◽  
Strong Ground Motion ◽  
Strong Dependence ◽  
Strong Motion ◽  
Vertical Acceleration ◽  
Data Set ◽  
Attenuation Relationships ◽  
Geological Conditions ◽  
Ground Motion Records ◽  
Strong Ground

In the aftermath of two destructive urban earthquakes in 1999 in Turkey, empirical models of strong motion attenuation relationships that have been previously developed for North American and European earthquakes have been utilized in a number of national seismic hazard studies. However, comparison of empirical evidence and estimates present significant differences. For that reason, a data set created from a suite of 100 vertical strong ground motion records from 47 national earthquakes that occurred between 1976 and 2002 has been used to develop attenuation relationships for strong ground motion in Turkey. A consistent set of empirical attenuation relationships was derived for predicting vertical peak and pseudo-absolute vertical acceleration spectral ordinates in terms of magnitude, source-to-site distance, and local geological conditions. The study manifests the strong dependence of vertical to horizontal (V/H) acceleration ratio on spectral periods and relatively weaker dependence on site geology, magnitude, and distance. The V/H ratio is found to be particularly significant at the higher frequency end of the spectrum, reaching values as high as 0.9 at short distances on soil sites. The largest long-period spectral ratios are observed to occur on rock sites where they can reach values in excess of 0.5. These results raise misgivings concerning the practice of assigning the V/H ratio a standard value of two-thirds. Hence, nonconservatism of this value at short periods and its conservatism at long periods underline the need for its revision, at least for practice in Turkey.

Seismology Based Ground Motion Attenuation Relationship for Sendai Area

2011 ◽  
Vol 382 ◽  
pp. 7-11
Author(s):  
Zheng Ru Tao ◽  
Xia Xin Tao ◽  
Xi Wei Wang
Keyword(s):  
Ground Motion ◽  
Strong Ground Motion ◽  
Stochastic Method ◽  
Empirical Relationships ◽  
Attenuation Relationships ◽  
Ground Motion Attenuation ◽  
Micro Genetic Algorithm ◽  
Fourier Spectra ◽  
Ground Motion Records ◽  
Strong Ground

For regions without adequate strong ground motion records, a method is developed to establish strong ground motion attenuation relationships, based on the stochastic method. Sendai area of Japan is selected as the target, since there are enough data from seismographic observation for calculation, and those from strong ground motion observation and some empirical relationships for result testing. Three parameters related to regional source and crustal medium are inversed by the micro-Genetic Algorithm. Total of 240 records from 77 small events, recorded by F-net, are adopted for the inversion. Fourier spectra are adopted as the objective function. These parameters are then taken into the stochastic method to estimate PGA. The regional ground motion attenuation relationships are compared with some strong ground motion records from K-NET and some empirical relationships to illustrate the reliability of this method.

Site-dependent spectra for earthquake-resistant design

1976 ◽  
Vol 66 (1) ◽  
pp. 221-243 ◽  
Author(s):  
H. Bolton Seed ◽  
Celso Ugas ◽  
John Lysmer
Keyword(s):  
United States ◽  
Statistical Analysis ◽  
Ground Motion ◽  
The United States ◽  
Design Criteria ◽  
Earthquake Resistant Design ◽  
Geological Conditions ◽  
Earthquake Resistant ◽  
Ground Motion Records ◽  
Spectral Shapes

abstract The paper presents the results of a statistical analysis of the spectral shapes of 104 ground-motion records obtained from 23 earthquakes, mostly in the western part of the United States. The analysis shows clear differences in spectral shapes for different soil and geological conditions, indicating the need for consideration of these effects in selecting earthquake-resistant design criteria.

Spatial Correlations in CyberShake Physics‐Based Ground‐Motion Simulations

2019 ◽  
Vol 109 (6) ◽  
pp. 2447-2458 ◽  
Author(s):  
Yilin Chen ◽  
Jack W. Baker
Keyword(s):  
Ground Motion ◽  
Prediction Models ◽  
Spatial Correlations ◽  
Ground Motion Simulation ◽  
Source Effects ◽  
Simulation Validation ◽  
Geological Conditions ◽  
Simulated Ground Motions ◽  
Strong Ground

Abstract When studying the performance of distributed infrastructure in earthquakes, spatial variations in strong ground motion have a significant impact. Currently, prediction models for spatial ground‐motion variations in future earthquakes are calibrated using ground‐motion observations from densely recorded earthquakes. Although useful, that calibration process requires strong assumptions about stationarity and isotropy of correlations. This article reports results from conducting analogous spatial variation estimation using physics‐based simulations from the CyberShake platform. This platform contains simulated ground motions from hundreds of thousands of rupture realizations, at locations throughout southern California, providing a synthetic ground‐motion catalog that is much richer than we could ever hope to achieve from recordings. That richness allows significant relaxation of stationarity and isotropy assumptions, and provides new insights regarding the role of source and path heterogeneity on the spatial correlation of ground‐motion amplitudes. The results suggest that geological conditions, source effects, and path effects have significant impacts on spatial correlations. In addition, this work serves as a new dimension of ground‐motion simulation validation, because the estimated correlations can be compared to results from past earthquakes.

scholarly journals Probabilistic sensitivity analysis of two suspension bridges in Istanbul, Turkey to near- and far-fault ground motion

2012 ◽  
Vol 12 (2) ◽  
pp. 459-473 ◽  
Author(s):  
Ö. Çavdar
Keyword(s):  
Ground Motion ◽  
Dynamic Responses ◽  
Suspension Bridges ◽  
Near Fault ◽  
Internal Forces ◽  
Ground Motion Records ◽  
Far Fault ◽  
Sensitivity Method ◽  
Mcs Method ◽  
Strong Ground

Abstract. The aim of this paper is to compare the near-fault and far-fault ground motion effects on the probabilistic sensitivity dynamic responses of two suspension bridges in Istanbul. Two different types of suspension bridges are selected to investigate the near-fault (NF) and far-fault (FF) ground motion effects on the bridge sensitivity responses. NF and FF strong ground motion records, which have approximately identical peak ground accelerations, of the Kocaeli (1999) earthquake are selected for the analyses. Displacements and internal forces are determined using the probabilistic sensitivity method (PSM), which is one type of stochastic finite element method. The efficiency and accuracy of the proposed algorithm are validated by comparison with results of the Monte Carlo Simulation (MCS) method. The displacements and internal forces obtained from the analyses of suspension bridges subjected to each fault effect are compared with each other. It is clearly seen that there is more seismic demand on displacements and internal forces when suspension bridges are subjected to NF and FF ground motion.

FUZZY PATTERN CLASSIFICATION OF STRONG GROUND MOTION RECORDS

2005 ◽  
Vol 9 (3) ◽  
pp. 307-332 ◽  
Author(s):  
ARZHANG ALIMORADI ◽  
SHAHRAM PEZESHK ◽  
FARZAD NAEIM ◽  
HICHEM FRIGUI
Keyword(s):  
Ground Motion ◽  
Pattern Classification ◽  
Strong Ground Motion ◽  
Fuzzy Pattern ◽  
Ground Motion Records ◽  
Strong Ground
Sign in / Sign up

Export Citation Format

Share Document