Seismic upgrading of bridges isolated with SF-ED devices: Large-scale model testing on shaking table

Abstract

Results of original experimental research, obtained during shaking table tests on a large-scale bridge model equipped with an advanced seismic protection system type USI-SF, are presented in the paper. The installed basic seismic isolation system is created by applying novel double spherical rolling seismic bearing (DSRSB) devices, while qualitative upgrading of seismic performances is made using the installed advanced multi-directional space flange energy dissipation (SF-ED) devices. Research results show that significant qualitative improvement of seismic performances of isolated road bridges can be achieved using DSRSB and SF-ED devices.Seizmičko poboljšanje izoliranih mostova pomoću uređaja SF-ED: Ispitivanje modela u velikom mjerilu na potresnom stolu U radu su prikazani rezultati originalnog eksperimentalnog istraživanja na potresnom stolu modela mosta u velikom mjerilu koji je opremljen naprednim sustavom seizmičke zaštite tipa USI-SF. Instalirani osnovni sustav seizmičke izolacije izveden je primjenom novih dvojnih kružnih kotrljajućih seizmičkih ležajeva (DSRSB), a kvalitativno poboljšanje seizmičkih karakteristika provedeno je pomoću instaliranih naprednih višesmjernih prostornih pojasnih uređaja za rasap energije (SF-ED). Rezultati istraživanja pokazuju da se primjenom uređaja DSRSB i SF-ED mogu postići značajna kvalitativna poboljšanja seizmičkih karakteristika izoliranih cestovnih mostova. Seismische Verbesserung der mit dem Gerät SF-ED isolierten Brücken: Untersuchung des Modells in großem Maßstab auf dem ErdbebentischIn der Abhandlung werden die Ergebnisse der ursprünglichen experimentellen Untersuchung des Brückenmodells in großem Maßstab auf dem Erdbebentisch dargelegt, das mit einem fortschrittlichen System des seismischen Schutzes des Typs USI-SF ausgestattet ist. Das installierte seismische Basisisoliersystem wurde durch Verwendung neuer doppelter kreisrunder rollender seismischer Lager ausgeführt (DSRSB), und die qualitative Verbesserung der seismischen Eigenschaften wurde mithilfe der installierten fortschrittlichen multidirektionalen räumlichen Energieverteilungsvorrichtung (SF-ED) durchgeführt. Die Ergebnisse der Untersuchungen zeigen, dass man durch die Verwendung der Geräte DSRSB und SF-ED eine Verbesserung der seismischen Eigenschaften der isolierten Straßenbrücken erreichen kann. Schlüsselwörter:Brücke, seismische Isolierung, Duktilität, Energieverteilung, seismische Sicherheit 1 Assist.Prof. Jelena Ristić, PhD. CE

Seismic upgrading of isolated bridges with SF-ED devices: Analytical study validated by shaking table testing

“…The second part of the study is based on the results of a previous extensive original experimental investigation, including the results of the nonlinear quasi-static tests of the new SF-ED devices and results of the successfully completed unique seismic shaking table tests of the constructed novel USI-SF bridge prototype model. The integral results were systematically presented, described, analysed and published, [23]. The study of results, and specific observations derived from the previously conducted experimental part of the study, enabled successful realization of the highly-significant extended complementary investigation, presented in this paper.…”

“…The seismic energy dissipation system installed in the tested USI-SF bridge prototype model was composed of the newly developed basic type of SF energy dissipation device [23]. The main development steps for the new basic SF-ED-L1R device type, including design, production, testing as well as the final observations from the experimental hysteretic behaviour tests, were presented in the mentioned paper.…”

“…A refined 3D analytical model formulated by using ANSYS computer software [24] was implemented for numerical simulation of the hysteretic response of the new types of SF-ED devices. The advanced, experimentally verified refined nonlinear 3D modelling concept described in [23], has been consistently and successfully implemented for realization of the present extended study.…”

“…It includes original experimental validation of actual seismic performances of the USI-SF system under the effects of very strong earthquake excitations. To meet the stated objectives, a large-scale physical model of a typical three-span prototype bridge was constructed and used for shaking table tests [23],…”