000011991 001__ 11991
000011991 005__ 20141205160008.0
000011991 04107 $$aeng
000011991 046__ $$k2008-10-12
000011991 100__ $$aViallet, E.
000011991 24500 $$aOn the Use of a Bayesian Updating Technique to Get Probabilistic Seismic Hazard Assessment More Rugged

000011991 24630 $$n14.$$pProceedings of the 14th World Conference on Earthquake Engineering
000011991 260__ $$b
000011991 506__ $$arestricted
000011991 520__ $$2eng$$aSince the basic work of Cornell, many studies have been conducted in order to evaluate the probabilistic seismic hazard (PSHA) of nuclear power plants. In general, results of such studies are used as inputs for seismic PSA. Such approaches are nowadays considered as well established and come more and more used worldwide, generally in addition to deterministic approaches. Nevertheless, some discrepancies have been observed recently in some PSHA, especially from studies conducted in areas with low to moderate seismicity. The lessons learnt from these results lead to conclude that, due to uncertainties inherent to such a domain, some deterministic choices have to be taken and, depending on expert judgment, may lead to strong differences in terms of seismic motion evaluation. In that context, the objective of this paper is to point out some difficulties that may appear in the development of PSHA studies and to propose an approach that may be used to address epistemic uncertainties. The key point, which corresponds to the innovating point of the process, is the use of instrumental experience feedback to update the results of a PSHA. The method used here is based on a Bayesian updating technique including real observations as conditional events, with their own probabilistic distribution. The results presented here point out that a PSHA must be conducted in a real probabilistic spirit that is totally different from a deterministic approach (the choice of “best-estimate” or “median” input data instead of “conservative“ ones is one of the key points). In addition, logic tree procedure, which seems to be the most appropriate way to account for epistemic uncertainties, does not quantify the variability on the physical parameter itself but quantify variability on expert opinion. This may lead to an important bias in a PSHA. Finally, results from PSHA may be strongly different from real seismicity, as recorded, especially depending on previous considerations. Then, the comparison to the instrumental experience data appears to be necessary to address such difficulties. In that context, the use of the Bayesian updating technique presented in this paper may become a necessary tool to address epistemic uncertainties in PSHA and its performances could allow to get PSHA more rugged and consistent with observations.

000011991 540__ $$aText je chráněný podle autorského zákona č. 121/2000 Sb.
000011991 653__ $$aPSHA, Bayesian approaches, Instrumental experience feedback, Updating technique

000011991 7112_ $$a14th World Conference on Earthquake Engineering$$cBejing (CN)$$d2008-10-12 / 2008-10-17$$gWCEE15
000011991 720__ $$aViallet, E.$$iHumbert, N.$$iMartin, C.$$iSecanell, R.
000011991 8560_ $$ffischerc@itam.cas.cz
000011991 8564_ $$s651855$$uhttps://invenio.itam.cas.cz/record/11991/files/07-0116.pdf$$yOriginal version of the author's contribution as presented on CD, Paper ID: 07-0116.
000011991 962__ $$r9324
000011991 980__ $$aPAPER