Characterization of Site Conditions for Selected Seismic Stations in Eastern Part of Romania

• Autorzy: Grecu B. , Zaharia B. , Diaconescu M. , Bala A. , Nastase E. , Constantinescu E. , Tataru D.

Identyfikatory

DOI

10.1007/s11600-018-0117-2

• Języki publikacji: EN

Abstrakty

EN

Strong motion data are essential for seismic hazard assessment. To correctly understand and use this kind of data is necessary to have a good knowledge of local site conditions. Romania has one of the largest strong motion networks in Europe with 134 real-time stations. In this work, we aim to do a comprehensive site characterization for eight of these stations located in the eastern part of Romania. We make use of a various seismological dataset and we perform ambient noise and earthquake-based investigations to estimate the background noise level, the resonance frequencies and amplification of each site. We also derive the Vs30 parameter from the surface shear-wave velocity profiles obtained through the inversion of the Rayleigh waves recorded in active seismic measurements. Our analyses indicate similar results for seven stations: high noise levels for frequencies larger than 1 Hz, well defined fundamental resonance at low frequencies (0.15-0.29 Hz), moderate amplification levels (up to 4 units) for frequencies between 0.15 and 5-7 Hz and same soil class (type C) according to the estimated Vs30 and Eurocode 8. In contrast, the eighth station for which the soil class is evaluated of type B exhibits a very good noise level for a wide range of frequencies (0.0120 Hz), a broader fundamental resonance at high frequencies (~ 8 Hz) and a flat amplification curve between 0.1 and 3-4 Hz.

Słowa kluczowe

EN

resonance frequency; Rayleigh waves; VS30; soil amplification; ambient seismic noise

PL

częstotliwość rezonansowa; fale Rayleigha; VS30

• Wydawca: Instytut Geofizyki PAN ; Springer
• Czasopismo: Acta Geophysica
• Rocznik: 2018
• Tom: Vol. 66, no. 2
• Strony: 153--165
• Opis fizyczny: Bibliogr. 30 poz.

Twórcy

autor

Grecu B.

• National Institute for Earth Physics, Măgurele, Romania

autor

Zaharia B.

• National Institute for Earth Physics, Măgurele, Romania

autor

Diaconescu M.

• National Institute for Earth Physics, Măgurele, Romania

autor

Bala A.

• National Institute for Earth Physics, Măgurele, Romania

autor

Nastase E.

• National Institute for Earth Physics, Măgurele, Romania

autor

Constantinescu E.

• National Institute for Earth Physics, Măgurele, Romania

autor

Tataru D.

• National Institute for Earth Physics, Măgurele, Romania

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Uwagi

Opracowanie rekordu w ramach umowy 509/P-DUN/2018 ze środków MNiSW przeznaczonych na działalność upowszechniającą naukę (2018)