AN INVESTIGATION ON THE EXACT AND APPROXIMATE DISTRIBUTION OF CONDITIONAL SPECTRUM USING SEISMIC HAZARD DISAGGREGATION

Selection of recorded ground motions is an important consideration in nonlinear dynamic analysis of structures. Owing to the deficiencies of previous implementations, the idea of Conditional Mean Spectrum (CMS) was introduced and different aspects and applications of this site-specific spectrum have been investigated previously. However, the objectives following here are mainly focused on (1) providing deep insight into the conditioning status of probabilistic seismic hazard disaggregation for constructing exact distribution of Conditional Spectrum (CS) (i.e. occurrence and/or exceedance of target spectral acceleration), (2) improving existing approximate approach for construction of CMS and its associated variance especially for sites being affected by drastically different events and defining the conditions for which the approximate methods lead to questionable results and finally (3) elucidating some vagueness about applications of CMS for specific situations through a real case study offshore site located at South Pars Gas Field in Persian Gulf region. In the case, when the hazard of the site is influenced by different seismic sources, which may have dissimilar event characteristics, alternative for current approximate CMS is investigated which secures the minimum deviation from the exact solution.

کلیدواژه ها:

Ground Motions ، Nonlinear Dynamic Analysis ، Conditional Mean Spectrum (Cms) ، Probabilistic Seismic Hazard Disaggregation