Common Best Practice Procedures for Site and Seismic Station Characterization: An European Initiative

Date: 4/26/2019

Time: 08:30 AM

Room: Pine

Site characterization is a key input in seismic hazard, risk assessment and seismic design. Although the number of strong-motion stations in free-field and engineered structures has largely increased in the last twenty years, only a limited number of instrumented sites includes site condition indicators: mostly geology and EC8 soil class, more rarely measured Vs30 and Vs profiles, without any quality assessment in most cases. This lack of information is a critical issue, e.g. for deriving reference-rock or soil velocity profiles for region-specific GMPEs, site-specific hazard assessment, Vs-kappa adjustments, seismic response of engineering infrastructures, risk modeling at urban or regional scale. Within the framework of the SERA “Seismology and Earthquake Engineering Research Infrastructure Alliance for Europe” Horizon 2020 Project, a networking activity has been set up to propose a comprehensive European strategy and standards fostering site characterization of seismic stations in Europe.

We will present the main outcomes regarding common best practice procedures for site and seismic station characterization. In order to evaluate the most relevant site characterization scalar, depth- and frequency-dependant indicators for site response purposes (e.g. Vs30, resonance period, velocity profiles, kappa, etc.), we sent an international questionnaire to the broad seismological and engineering community. Aside prioritizing the most critical set of indicators to be measured at a given site, it also allowed estimating the level of difficulty and the related cost for estimating each single indicator. We defined an overall quantitative quality metric scheme for site characterization that combines quality of single indicator, combination and overall compatibility of various indicators. We finally propose recommendation guidelines for the necessary information to allow a reliable description of the seismic characterization of single site and associated quality index. The outcome has been shared within a broad scientific community in Europe and worldwide.

Presenting Author: Cecile Cornou

Authors