Deterministic seismic Site Response Analysis (SRA) is commonly performed in conjunction with a Probabilistic Seismic Hazard Analysis (PSHA) to estimate amplification or deamplification of soil motion due to earthquake ground shaking. Despite its wide acceptance, this approach neglects the uncertainty in the site response, with the result that the final occurrence rate (return period) of surface spectra is unknown. Several methods are available in literature to combine PSHA and SRA results, ranging from simplified approaches to fully probabilistic methods. One fully probabilistic approach is to incorporate soil amplification in the hazard calculation to obtain site-specific GMPEs. SRA results are used to adjust GMPEs median and standard deviation predictions for expected soil conditions. The PSHA is then repeated using the site-specific GMPEs to estimate the surface spectra for a given exceedance probability. This paper illustrates a methodology for fully probabilistic approach to SRA and its application to a representative case study. Attention is given to possible fields of application, as well as the required computational effort.
Daniela Tonoli, Francesca Ioele, Pamela Poggi, Daniele Bertalot, Omar Zanoli, Eric J. Parker and Emilia Fiorini
Keywords: Probabilistic Site Response, PSHA, Site Effects
Publisher: DFI