000018454 001__ 18454
000018454 005__ 20170118182223.0
000018454 04107 $$aeng
000018454 046__ $$k2017-01-09
000018454 100__ $$aHusen, Stephan
000018454 24500 $$aEarthquake Scenarios for School Buildings in the City of Basel (Switzerland)

000018454 24630 $$n16.$$pProceedings of the 16th World Conference on Earthquake Engineering
000018454 260__ $$b
000018454 506__ $$arestricted
000018454 520__ $$2eng$$aDeveloping earthquake scenarios for cities in areas with a moderate seismicity is a challenge due to the limited amount of available seismological and engineering data, which is a source of large uncertainties. This concerns both the seismic hazard, for which only recordings for small earthquakes are available and the unknown earthquake resistance of pre-code structures that constitute the vast majority of the building stock. Within the framework of the risk mitigation project of the city of Basel, a pilot study has been performed to estimate the impact and consequences of strong earthquakes of different sizes and return periods on school buildings. The hazard analysis benefitted from the new Swiss Probabilistic Seismic Hazard Model of 2015 computed for a welldefined reference rock velocity profile. The city of Basel is located in the Rhinegraben, where sedimentary deposits of several hundred meters thickness substantially influence the ground motion. This ground motion amplification has been estimated at high spatial resolution using different methods, including recordings of small events on a dense strong motion network. This estimation benefitted from 20 years of geophysical investigations and a large number of numerical simulations of earthquake ground motion from strong events. A selection of 121 cantonal school buildings in Basel have been classified according to a specifically developed typology. Most of them are unreinforced masonry or reinforced concrete shear-wall buildings. Displacement-based analyses have been performed to calculate capacity curves representing the behavior of the different types. Based on these capacity curves, fragility and vulnerability curves were derived with new methods with a special attention paid to the uncertainties and their propagation. The fragility curves have been checked against empirical curves to ensure that the analysis method yielded realistic results and further improved. The scenarios considered in the study are based on historical events, in particular the 1356 Basel event (Mw=6.6), and on the de-aggregation of the Swiss Seismic Hazard Model for 475 years return period. The computations were run with the Openquake software, propagating all the recognized uncertainties. The scenarios allow us to quantify the number of casualties, the number of pupils that cannot go to school and financial losses that such events would cause. Moreover, a long-term retrofitting project is currently implemented for the school buildings, not only related to earthquake safety. A building type is assigned to the building before and after the retrofit, and a cost-benefit analysis is performed to determine the impact of the retrofitting on the earthquake safety. A framework for real-time assessment is also developed, and a prototype Shakemap at high spatial resolution was implemented as test version.

000018454 540__ $$aText je chráněný podle autorského zákona č. 121/2000 Sb.
000018454 653__ $$aseismic risk; seismic vulnerability; fragility curves; displacement-based assessment; Openquake

000018454 7112_ $$a16th World Conference on Earthquake Engineering$$cSantiago (CL)$$d2017-01-09 / 2017-01-13$$gWCEE16
000018454 720__ $$aHusen, Stephan$$iFäh, Donat$$iLestuzzi, Pierino$$iHannewald, Pia$$iMichel, Clotaire$$iRoth, Martin
000018454 8560_ $$ffischerc@itam.cas.cz
000018454 8564_ $$s434970$$uhttps://invenio.itam.cas.cz/record/18454/files/1491.pdf$$yOriginal version of the author's contribution as presented on USB, paper 1491.
000018454 962__ $$r16048
000018454 980__ $$aPAPER