Probabilistic seismic hazard map for Romania as a basis for a new building code

Abstract

Abstract.A seismic hazard map proposed as part of a new building code for Romania is presented here on basis of the recommendations in EUROCODE 8.Seismic source zones within an area of about 200 km around Romania were constructed considering seismicity, neotectonics and geological development. The probabilistic seismic hazard assessment in terms of intensities is performed following Cornell (1968) with the program EQRISK (see Mc Guire, 1976), modified by us for use of intensities.To cope with the irregular isoseismals of the Vrancea intermediate depth earthquakes a factor is introduced to the attenuation law (Kövesligethy, 1907). Using detailed macroseismic maps of three earthquakes is calculated by fitting the attenuation law to observed intensities, i.e. to local ground conditions. Strong local variation of is avoided by a gridding of 0.5 • in longitude and 0.25 • in latitude. The contribution of the Vrancea intermediate depth zone to the seismic hazard at each grid point is computed with the corresponding representative . A seismogenic depth of 120 km is assumed.The final seismic hazard is the combination of both contributions, of zones with crustal earthquakes and of the Vrancea intermediate depth earthquakes zone. Calculations are done for a recurrence period of 95, 475 and 10 000 years. All maps show the dominating effects of the intermediate depth earthquakes in the Vrancea zone, also for the capital Bucharest.

Probabilistic seismic hazard map for Bulgaria as a basis for a new building code

“…The seismic source zones for the territory of Bulgaria are based on Bonchev et al (1982) and close to those defined by Sokerova et al (1992) and Dachev et al (1995). The boundaries of the seismic source zones outside Bulgaria were chosen to reflect the seismicity adequately with respect to the tectonic units and lithosphere structure; in the northern part of the study area they follow the zonation given by Ardeleanu et al (2005). All earthquakes outside the designed sources are assigned to the "background seismicity".…”

“…Using detailed macroseismic maps of three strong Vrancea intermediate depth earthquakes (see Ardeleanu et al, 2005) is calculated for each observation point. 22˚E 22˚E 23˚E 23˚E 24˚E 24˚E 25˚E 25˚E 26˚E 26˚E 27˚E 27˚E 28˚E 28˚E 29˚E 29˚E 30˚E 30˚E 41˚N 42˚N 43˚N 44˚N 45˚N 22˚E 22˚E 23˚E 23˚E 24˚E 24˚E 25˚E 25˚E 26˚E 26˚E 27˚E 27˚E 28˚E 28˚E 29˚E 29˚E 30˚E 30˚E 41˚N 42˚N 43˚N 44˚N …”

“…To cope with the irregular isoseismals of the Vrancea intermediate depth earthquakes a special attenuation factor is introduced (Ardeleanu et al, 2005), using detailed macroseismic maps of three major earthquakes.…”

Selection of the Appropriate Methodology for Earthquake Safety Assessment of Dam Structures

“…Characterization of seismic activity and temporal distribution of earthquake recurrence. (Kramer, 1996) DSHA and PSHA have been performed by different researchers in specific sites according to their project goals and importance (Chandler et al 2001;Fat-Helbary and Tealb 2002;AlHomoud, 2003;Ardeleanu et al 2005;Simeonova et al 2006;Orhan et al 2007;Nakajima et al 2007;Tosun and Seyrek, 2006;Tosun et al 2007;Seyrek and Tosun, 2011).…”

A probabilistic approach for earthquake hazard assessment of the Province of Eskişehir, Turkey

“…One method may have priority over the other, depending on the seismic environment and the scope of the project (McGuire, 2001). DSHA and PSHA have been performed by different researchers in specific sites according to their project scopes and importance (Nakajima et al, 2007;Tosun et al, 2007;Simeonova et al, 2006;Ardeleanu et al, 2005;Kayabalı, 2002;Chandler et al, 2001).…”