000013077 001__ 13077
000013077 005__ 20161114160326.0
000013077 04107 $$aeng
000013077 046__ $$k2009-06-22
000013077 100__ $$aBelsham C., S.
000013077 24500 $$aExploring uncertainties in probabilistic seismic hazard analysis through a stochastic source-to-site seismic model

000013077 24630 $$n2.$$pComputational Methods in Structural Dynamics and Earhquake Engineering
000013077 260__ $$bNational Technical University of Athens, 2009
000013077 506__ $$arestricted
000013077 520__ $$2eng$$aEnvironmental loading is often a significant design consideration for civil engineering undertakings and it is often the case that those loading conditions dominate in terms of the uncertainties that need to be taken into account. This is particularly so when the inertial forces due to earthquakes need to be considered. This paper presents a way of quantifying uncertainties due to earthquakes by means of a stochastic source-to-site model (SSTSM) and compares the findings with those of existing empirically based methodologies. The approach described incorporates features from Random Vibration Theory (RVT) that provide for varying probabilities of exceedence and hence incorporates uncertainties into the SSTSM. The concept of model matching between the SSTSM and a mean Empirical Strong Ground Motion Prediction Equation (ESGMPE) enables the generalised uncertainty in all the significant variables to be calibrated. The significance of the distinction between epistemic and aleatory uncertainty is considered in the context of SSTSM. An example is given where this has been applied to a rock site in Western North America. The matched SSTSM provides a vehicle with which to investigate several issues that are currently of interest in the application of ESGMPEs to seismic hazard studies. One is whether it is appropriate to truncate the assumed lognormal distribution representing the uncertainty in the ESGMPE which has implications for selecting the fractile against which the design is to be delivered. The uncertainties that arise from the geotechnical effect of the local site response are explored using an approach based on transfer matrices and by examining probabilistically the properties of the spectral response. The study suggests that, within the limitations of the examples, large excursions of spectral accelerations are unlikely to occur and if they do, it is probable that it would be a single occurrence. The study also reveals some anomalies which are identified for future study. The analysis has been performed entirely in the Mathcad software environment.

000013077 540__ $$aText je chráněný podle autorského zákona č. 121/2000 Sb.
000013077 653__ $$aProbabilistic Seismic Hazard Analysis, Uncertainty, Source to Site model, Random Vibration Theory, Model matching, Empirical Strong Ground Motion Prediction Equations. Abstract. Environmental loading is often a significant design consideration for civil engineering undertakings and it is often the case that those loading conditions dominate in terms of the uncertainties that need to be taken into account. This is particularly so when the inertial forces due to earthquakes need to be considered. This paper presents a way of quantifying uncertainties due to earthquakes by means of a stochastic source-to-site model (SSTSM) and compares the findings with those of existing empirically based methodologies. The approach described incorporates features from Random Vibration Theory (RVT) that provide for varying probabilities of exceedence and hence incorporates uncertainties into the SSTSM. The concept of model matching between the SSTSM and a mean Empirical Strong Ground Motion Prediction Equation (ESGMPE) enables the generalised uncertainty in all the significant variables to be calibrated. The significance of the distinction between epistemic and aleatory uncertainty is considered in the context of SSTSM. An example is given where this has been applied to a rock site in Western North America. The matched SSTSM provides a vehicle with which to investigate several issues that are currently of interest in the application of ESGMPEs to seismic hazard studies. One is whether it is appropriate to truncate the assumed lognormal distribution representing the uncertainty in the ESGMPE which has implications for selecting the fractile against which the design is to be delivered. The uncertainties that arise from the geotechnical effect of the local site response are explored using an approach based on transfer matrices and by examining probabilistically the properties of the spectral response. The study suggests that, within the limitations of the examples, large excursions of spectral accelerations are unlikely to occur and if they do, it is probable that it would be a single occurrence. The study also reveals some anomalies which are identified for future study. The analysis has been performed entirely in the Mathcad software environment.

000013077 7112_ $$aCOMPDYN 2009 - 2nd International Thematic Conference$$cIsland of Rhodes (GR)$$d2009-06-22 / 2009-06-24$$gCOMPDYN2009
000013077 720__ $$aBelsham C., S.
000013077 8560_ $$ffischerc@itam.cas.cz
000013077 8564_ $$s471961$$uhttps://invenio.itam.cas.cz/record/13077/files/CD103.pdf$$yOriginal version of the author's contribution as presented on CD, section: Statistical and probabilistic methods in computational mechanics to treat aleatory and epistemic uncertainties in structural and/or geotechnical systems and their loading environment - iii (MS).
000013077 962__ $$r13074
000013077 980__ $$aPAPER