000021786 001__ 21786
000021786 005__ 20170622131304.0
000021786 04107 $$aeng
000021786 046__ $$k2017-06-15
000021786 100__ $$aKaratzia, Xenia
000021786 24500 $$aGEOTECHNICAL SEISMIC ISOLATION USING EPS GEOFOAM AROUND PILES

000021786 24630 $$n6.$$pComputational Methods in Structural Dynamics and Earhquake Engineering
000021786 260__ $$bNational Technical University of Athens, 2017
000021786 506__ $$arestricted
000021786 520__ $$2eng$$aThe feasibility of a new geotechnical seismic isolation system for pile-supported structures, such as bridge piers on monopiles, is investigated. The isolation system utilizes a soft annular zone of viscoelastic material, such as EPS geofoam, around the upper part of the pile. The presence of the EPS elongates the fundamental natural period of the structure and also modifies its damping. For simplicity and as a proof of concept, the superstructure is considered a simple oscillator. Based on a dynamic Winkler model for pile-soil interaction, the problem is treated analytically leading to a simple design-oriented analysis method. Closedform solutions are obtained for: (a) the lateral stiffness of the structure-foundation system, (b) the corresponding fundamental period, and (c) the overall damping. Numerical analyses in the frequency domain by means of the computer code SPIAB verify the above analytical predictions. Analyses in the time domain are also carried out to examine the effect of geofoam on the dynamic response. Results in terms of base shear, maximum pile bending moment, and displacement at deck level are presented in dimensionless form, allowing for quantification of the effect of geofoam on seismic performance. It is shown that the presence of geofoam around the pile can reduce the seismic demand, rendering the proposed method a promising, inexpensive alternative to structural protective systems.

000021786 540__ $$aText je chráněný podle autorského zákona č. 121/2000 Sb.
000021786 653__ $$aGeotechnical Isolation, Pile Foundations, Bridge Pier, EPS Geofoam, Period Elongation.

000021786 7112_ $$aCOMPDYN 2017 - 6th International Thematic Conference$$cRhodes Island (GR)$$d2017-06-15 / 2017-06-17$$gCOMPDYN2017
000021786 720__ $$aKaratzia, Xenia$$iMylonakis, George
000021786 8560_ $$ffischerc@itam.cas.cz
000021786 8564_ $$s703379$$uhttps://invenio.itam.cas.cz/record/21786/files/17924.pdf$$yOriginal version of the author's contribution as presented on CD, section: [MS11] Recent advances and challenges in geotechnical earthquake engineering
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000021786 962__ $$r21500
000021786 980__ $$aPAPER