000015756 001__ 15756
000015756 005__ 20161115135328.0
000015756 04107 $$aeng
000015756 046__ $$k2013-06-12
000015756 100__ $$aElhowary, H.
000015756 24500 $$aEffect of Spatially Variable Ground Motions on the Seismic Fragility of Box Girder Continuous Bridges

000015756 24630 $$n34.$$pComputational Methods in Structural Dynamics and Earhquake Engineering
000015756 260__ $$bNational Technical University of Athens, 2013
000015756 506__ $$arestricted
000015756 520__ $$2eng$$aSeismic design of bridges is usually performed assuming that all bridge supports experience the same ground motion (i.e. uniform input). However, strong-motion recorders of special seismograph arrays already demonstrated that significant spatial variation do exist in seismic ground motions [1]. The spatial variation of seismic ground motions is due to various sources including the loss of coherency, which results from random reflections and refractions as the waves travel through the soil, and the wave-passage effect. The present paper illustrates the impact of ground motion spatial variability on the seismic performance of continuous box girder bridges in both bridge orthogonal directions (longitudinal and transverse). For illustration purposes, a nine-span bridge with a total length of 430m is adopted. Non-linear time history analyses are carried out using OPENSEES software [2]. The wave passage effects are examined individually using a set of real records originally extracted from the PEER (Pacific Earthquake Engineering Center) Strong Motion Database using different apparent wave propagation velocities. Then, the loss of coherency effect is investigated using a set of artificially simulated seismic ground motions using the SIM software developed by Ramadan and Novak [3& 4] considering different degrees of loss in coherency and various ground motion frequency contents. Results of the non-linear time history analyses performed in an incremental dynamic analysis context are hence manipulated through a probabilistic analysis framework to generate fragility curves associated with various performance levels for the case study bridge. Fragility curves giving the conditional probability of exceeding various performance levels are then integrated with generated hazard curves defining the expected seismic hazard in Egypt. The outcome of this integration process results in values of mean annual frequency of exceeding pre-defined performance levels. 1

000015756 540__ $$aText je chráněný podle autorského zákona č. 121/2000 Sb.
000015756 653__ $$aSpatially variable ground motions, Seismic Fragility, Box Girder Continuous bridges

000015756 7112_ $$aCOMPDYN 2013 - 4th International Thematic Conference$$cIsland of Kos (GR)$$d2013-06-12 / 2013-06-14$$gCOMPDYN2013
000015756 720__ $$aElhowary, H.$$iRamadan, O.$$iMehanny, S.
000015756 8560_ $$ffischerc@itam.cas.cz
000015756 8564_ $$s442859$$uhttps://invenio.itam.cas.cz/record/15756/files/1402.pdf$$yOriginal version of the author's contribution as presented on CD, section: CD-RS 21 SEISMIC DESIGN AND ASSESSMENT OF BRIDGES
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000015756 962__ $$r15525
000015756 980__ $$aPAPER